ide-{floppy,tape}: PC_FLAG_DMA_RECOMMENDED -> PC_FLAG_DMA_OK
[deliverable/linux.git] / drivers / ide / ide-tape.c
1 /*
2 * IDE ATAPI streaming tape driver.
3 *
4 * Copyright (C) 1995-1999 Gadi Oxman <gadio@netvision.net.il>
5 * Copyright (C) 2003-2005 Bartlomiej Zolnierkiewicz
6 *
7 * This driver was constructed as a student project in the software laboratory
8 * of the faculty of electrical engineering in the Technion - Israel's
9 * Institute Of Technology, with the guide of Avner Lottem and Dr. Ilana David.
10 *
11 * It is hereby placed under the terms of the GNU general public license.
12 * (See linux/COPYING).
13 *
14 * For a historical changelog see
15 * Documentation/ide/ChangeLog.ide-tape.1995-2002
16 */
17
18 #define IDETAPE_VERSION "1.20"
19
20 #include <linux/module.h>
21 #include <linux/types.h>
22 #include <linux/string.h>
23 #include <linux/kernel.h>
24 #include <linux/delay.h>
25 #include <linux/timer.h>
26 #include <linux/mm.h>
27 #include <linux/interrupt.h>
28 #include <linux/jiffies.h>
29 #include <linux/major.h>
30 #include <linux/errno.h>
31 #include <linux/genhd.h>
32 #include <linux/slab.h>
33 #include <linux/pci.h>
34 #include <linux/ide.h>
35 #include <linux/smp_lock.h>
36 #include <linux/completion.h>
37 #include <linux/bitops.h>
38 #include <linux/mutex.h>
39 #include <scsi/scsi.h>
40
41 #include <asm/byteorder.h>
42 #include <linux/irq.h>
43 #include <linux/uaccess.h>
44 #include <linux/io.h>
45 #include <asm/unaligned.h>
46 #include <linux/mtio.h>
47
48 enum {
49 /* output errors only */
50 DBG_ERR = (1 << 0),
51 /* output all sense key/asc */
52 DBG_SENSE = (1 << 1),
53 /* info regarding all chrdev-related procedures */
54 DBG_CHRDEV = (1 << 2),
55 /* all remaining procedures */
56 DBG_PROCS = (1 << 3),
57 /* buffer alloc info (pc_stack & rq_stack) */
58 DBG_PCRQ_STACK = (1 << 4),
59 };
60
61 /* define to see debug info */
62 #define IDETAPE_DEBUG_LOG 0
63
64 #if IDETAPE_DEBUG_LOG
65 #define debug_log(lvl, fmt, args...) \
66 { \
67 if (tape->debug_mask & lvl) \
68 printk(KERN_INFO "ide-tape: " fmt, ## args); \
69 }
70 #else
71 #define debug_log(lvl, fmt, args...) do {} while (0)
72 #endif
73
74 /**************************** Tunable parameters *****************************/
75 /*
76 * After each failed packet command we issue a request sense command and retry
77 * the packet command IDETAPE_MAX_PC_RETRIES times.
78 *
79 * Setting IDETAPE_MAX_PC_RETRIES to 0 will disable retries.
80 */
81 #define IDETAPE_MAX_PC_RETRIES 3
82
83 /*
84 * With each packet command, we allocate a buffer of IDETAPE_PC_BUFFER_SIZE
85 * bytes. This is used for several packet commands (Not for READ/WRITE commands)
86 */
87 #define IDETAPE_PC_BUFFER_SIZE 256
88
89 /*
90 * In various places in the driver, we need to allocate storage
91 * for packet commands and requests, which will remain valid while
92 * we leave the driver to wait for an interrupt or a timeout event.
93 */
94 #define IDETAPE_PC_STACK (10 + IDETAPE_MAX_PC_RETRIES)
95
96 /*
97 * Some drives (for example, Seagate STT3401A Travan) require a very long
98 * timeout, because they don't return an interrupt or clear their busy bit
99 * until after the command completes (even retension commands).
100 */
101 #define IDETAPE_WAIT_CMD (900*HZ)
102
103 /*
104 * The following parameter is used to select the point in the internal tape fifo
105 * in which we will start to refill the buffer. Decreasing the following
106 * parameter will improve the system's latency and interactive response, while
107 * using a high value might improve system throughput.
108 */
109 #define IDETAPE_FIFO_THRESHOLD 2
110
111 /*
112 * DSC polling parameters.
113 *
114 * Polling for DSC (a single bit in the status register) is a very important
115 * function in ide-tape. There are two cases in which we poll for DSC:
116 *
117 * 1. Before a read/write packet command, to ensure that we can transfer data
118 * from/to the tape's data buffers, without causing an actual media access.
119 * In case the tape is not ready yet, we take out our request from the device
120 * request queue, so that ide.c could service requests from the other device
121 * on the same interface in the meantime.
122 *
123 * 2. After the successful initialization of a "media access packet command",
124 * which is a command that can take a long time to complete (the interval can
125 * range from several seconds to even an hour). Again, we postpone our request
126 * in the middle to free the bus for the other device. The polling frequency
127 * here should be lower than the read/write frequency since those media access
128 * commands are slow. We start from a "fast" frequency - IDETAPE_DSC_MA_FAST
129 * (1 second), and if we don't receive DSC after IDETAPE_DSC_MA_THRESHOLD
130 * (5 min), we switch it to a lower frequency - IDETAPE_DSC_MA_SLOW (1 min).
131 *
132 * We also set a timeout for the timer, in case something goes wrong. The
133 * timeout should be longer then the maximum execution time of a tape operation.
134 */
135
136 /* DSC timings. */
137 #define IDETAPE_DSC_RW_MIN 5*HZ/100 /* 50 msec */
138 #define IDETAPE_DSC_RW_MAX 40*HZ/100 /* 400 msec */
139 #define IDETAPE_DSC_RW_TIMEOUT 2*60*HZ /* 2 minutes */
140 #define IDETAPE_DSC_MA_FAST 2*HZ /* 2 seconds */
141 #define IDETAPE_DSC_MA_THRESHOLD 5*60*HZ /* 5 minutes */
142 #define IDETAPE_DSC_MA_SLOW 30*HZ /* 30 seconds */
143 #define IDETAPE_DSC_MA_TIMEOUT 2*60*60*HZ /* 2 hours */
144
145 /*************************** End of tunable parameters ***********************/
146
147 /* tape directions */
148 enum {
149 IDETAPE_DIR_NONE = (1 << 0),
150 IDETAPE_DIR_READ = (1 << 1),
151 IDETAPE_DIR_WRITE = (1 << 2),
152 };
153
154 struct idetape_bh {
155 u32 b_size;
156 atomic_t b_count;
157 struct idetape_bh *b_reqnext;
158 char *b_data;
159 };
160
161 /* Tape door status */
162 #define DOOR_UNLOCKED 0
163 #define DOOR_LOCKED 1
164 #define DOOR_EXPLICITLY_LOCKED 2
165
166 /* Some defines for the SPACE command */
167 #define IDETAPE_SPACE_OVER_FILEMARK 1
168 #define IDETAPE_SPACE_TO_EOD 3
169
170 /* Some defines for the LOAD UNLOAD command */
171 #define IDETAPE_LU_LOAD_MASK 1
172 #define IDETAPE_LU_RETENSION_MASK 2
173 #define IDETAPE_LU_EOT_MASK 4
174
175 /*
176 * Special requests for our block device strategy routine.
177 *
178 * In order to service a character device command, we add special requests to
179 * the tail of our block device request queue and wait for their completion.
180 */
181
182 enum {
183 REQ_IDETAPE_PC1 = (1 << 0), /* packet command (first stage) */
184 REQ_IDETAPE_PC2 = (1 << 1), /* packet command (second stage) */
185 REQ_IDETAPE_READ = (1 << 2),
186 REQ_IDETAPE_WRITE = (1 << 3),
187 };
188
189 /* Error codes returned in rq->errors to the higher part of the driver. */
190 #define IDETAPE_ERROR_GENERAL 101
191 #define IDETAPE_ERROR_FILEMARK 102
192 #define IDETAPE_ERROR_EOD 103
193
194 /* Structures related to the SELECT SENSE / MODE SENSE packet commands. */
195 #define IDETAPE_BLOCK_DESCRIPTOR 0
196 #define IDETAPE_CAPABILITIES_PAGE 0x2a
197
198 /* Tape flag bits values. */
199 enum {
200 IDETAPE_FLAG_IGNORE_DSC = (1 << 0),
201 /* 0 When the tape position is unknown */
202 IDETAPE_FLAG_ADDRESS_VALID = (1 << 1),
203 /* Device already opened */
204 IDETAPE_FLAG_BUSY = (1 << 2),
205 /* Attempt to auto-detect the current user block size */
206 IDETAPE_FLAG_DETECT_BS = (1 << 3),
207 /* Currently on a filemark */
208 IDETAPE_FLAG_FILEMARK = (1 << 4),
209 /* DRQ interrupt device */
210 IDETAPE_FLAG_DRQ_INTERRUPT = (1 << 5),
211 /* 0 = no tape is loaded, so we don't rewind after ejecting */
212 IDETAPE_FLAG_MEDIUM_PRESENT = (1 << 6),
213 };
214
215 /*
216 * Most of our global data which we need to save even as we leave the driver due
217 * to an interrupt or a timer event is stored in the struct defined below.
218 */
219 typedef struct ide_tape_obj {
220 ide_drive_t *drive;
221 ide_driver_t *driver;
222 struct gendisk *disk;
223 struct kref kref;
224
225 /*
226 * Since a typical character device operation requires more
227 * than one packet command, we provide here enough memory
228 * for the maximum of interconnected packet commands.
229 * The packet commands are stored in the circular array pc_stack.
230 * pc_stack_index points to the last used entry, and warps around
231 * to the start when we get to the last array entry.
232 *
233 * pc points to the current processed packet command.
234 *
235 * failed_pc points to the last failed packet command, or contains
236 * NULL if we do not need to retry any packet command. This is
237 * required since an additional packet command is needed before the
238 * retry, to get detailed information on what went wrong.
239 */
240 /* Current packet command */
241 struct ide_atapi_pc *pc;
242 /* Last failed packet command */
243 struct ide_atapi_pc *failed_pc;
244 /* Packet command stack */
245 struct ide_atapi_pc pc_stack[IDETAPE_PC_STACK];
246 /* Next free packet command storage space */
247 int pc_stack_index;
248 struct request rq_stack[IDETAPE_PC_STACK];
249 /* We implement a circular array */
250 int rq_stack_index;
251
252 /*
253 * DSC polling variables.
254 *
255 * While polling for DSC we use postponed_rq to postpone the current
256 * request so that ide.c will be able to service pending requests on the
257 * other device. Note that at most we will have only one DSC (usually
258 * data transfer) request in the device request queue.
259 */
260 struct request *postponed_rq;
261 /* The time in which we started polling for DSC */
262 unsigned long dsc_polling_start;
263 /* Timer used to poll for dsc */
264 struct timer_list dsc_timer;
265 /* Read/Write dsc polling frequency */
266 unsigned long best_dsc_rw_freq;
267 unsigned long dsc_poll_freq;
268 unsigned long dsc_timeout;
269
270 /* Read position information */
271 u8 partition;
272 /* Current block */
273 unsigned int first_frame;
274
275 /* Last error information */
276 u8 sense_key, asc, ascq;
277
278 /* Character device operation */
279 unsigned int minor;
280 /* device name */
281 char name[4];
282 /* Current character device data transfer direction */
283 u8 chrdev_dir;
284
285 /* tape block size, usually 512 or 1024 bytes */
286 unsigned short blk_size;
287 int user_bs_factor;
288
289 /* Copy of the tape's Capabilities and Mechanical Page */
290 u8 caps[20];
291
292 /*
293 * Active data transfer request parameters.
294 *
295 * At most, there is only one ide-tape originated data transfer request
296 * in the device request queue. This allows ide.c to easily service
297 * requests from the other device when we postpone our active request.
298 */
299
300 /* Data buffer size chosen based on the tape's recommendation */
301 int buffer_size;
302 /* merge buffer */
303 struct idetape_bh *merge_bh;
304 /* size of the merge buffer */
305 int merge_bh_size;
306 /* pointer to current buffer head within the merge buffer */
307 struct idetape_bh *bh;
308 char *b_data;
309 int b_count;
310
311 int pages_per_buffer;
312 /* Wasted space in each stage */
313 int excess_bh_size;
314
315 /* Status/Action flags: long for set_bit */
316 unsigned long flags;
317 /* protects the ide-tape queue */
318 spinlock_t lock;
319
320 /* Measures average tape speed */
321 unsigned long avg_time;
322 int avg_size;
323 int avg_speed;
324
325 /* the door is currently locked */
326 int door_locked;
327 /* the tape hardware is write protected */
328 char drv_write_prot;
329 /* the tape is write protected (hardware or opened as read-only) */
330 char write_prot;
331
332 u32 debug_mask;
333 } idetape_tape_t;
334
335 static DEFINE_MUTEX(idetape_ref_mutex);
336
337 static struct class *idetape_sysfs_class;
338
339 #define to_ide_tape(obj) container_of(obj, struct ide_tape_obj, kref)
340
341 #define ide_tape_g(disk) \
342 container_of((disk)->private_data, struct ide_tape_obj, driver)
343
344 static struct ide_tape_obj *ide_tape_get(struct gendisk *disk)
345 {
346 struct ide_tape_obj *tape = NULL;
347
348 mutex_lock(&idetape_ref_mutex);
349 tape = ide_tape_g(disk);
350 if (tape)
351 kref_get(&tape->kref);
352 mutex_unlock(&idetape_ref_mutex);
353 return tape;
354 }
355
356 static void ide_tape_release(struct kref *);
357
358 static void ide_tape_put(struct ide_tape_obj *tape)
359 {
360 mutex_lock(&idetape_ref_mutex);
361 kref_put(&tape->kref, ide_tape_release);
362 mutex_unlock(&idetape_ref_mutex);
363 }
364
365 /*
366 * The variables below are used for the character device interface. Additional
367 * state variables are defined in our ide_drive_t structure.
368 */
369 static struct ide_tape_obj *idetape_devs[MAX_HWIFS * MAX_DRIVES];
370
371 #define ide_tape_f(file) ((file)->private_data)
372
373 static struct ide_tape_obj *ide_tape_chrdev_get(unsigned int i)
374 {
375 struct ide_tape_obj *tape = NULL;
376
377 mutex_lock(&idetape_ref_mutex);
378 tape = idetape_devs[i];
379 if (tape)
380 kref_get(&tape->kref);
381 mutex_unlock(&idetape_ref_mutex);
382 return tape;
383 }
384
385 static void idetape_input_buffers(ide_drive_t *drive, struct ide_atapi_pc *pc,
386 unsigned int bcount)
387 {
388 struct idetape_bh *bh = pc->bh;
389 int count;
390
391 while (bcount) {
392 if (bh == NULL) {
393 printk(KERN_ERR "ide-tape: bh == NULL in "
394 "idetape_input_buffers\n");
395 ide_pad_transfer(drive, 0, bcount);
396 return;
397 }
398 count = min(
399 (unsigned int)(bh->b_size - atomic_read(&bh->b_count)),
400 bcount);
401 drive->hwif->input_data(drive, NULL, bh->b_data +
402 atomic_read(&bh->b_count), count);
403 bcount -= count;
404 atomic_add(count, &bh->b_count);
405 if (atomic_read(&bh->b_count) == bh->b_size) {
406 bh = bh->b_reqnext;
407 if (bh)
408 atomic_set(&bh->b_count, 0);
409 }
410 }
411 pc->bh = bh;
412 }
413
414 static void idetape_output_buffers(ide_drive_t *drive, struct ide_atapi_pc *pc,
415 unsigned int bcount)
416 {
417 struct idetape_bh *bh = pc->bh;
418 int count;
419
420 while (bcount) {
421 if (bh == NULL) {
422 printk(KERN_ERR "ide-tape: bh == NULL in %s\n",
423 __func__);
424 return;
425 }
426 count = min((unsigned int)pc->b_count, (unsigned int)bcount);
427 drive->hwif->output_data(drive, NULL, pc->b_data, count);
428 bcount -= count;
429 pc->b_data += count;
430 pc->b_count -= count;
431 if (!pc->b_count) {
432 bh = bh->b_reqnext;
433 pc->bh = bh;
434 if (bh) {
435 pc->b_data = bh->b_data;
436 pc->b_count = atomic_read(&bh->b_count);
437 }
438 }
439 }
440 }
441
442 static void idetape_update_buffers(struct ide_atapi_pc *pc)
443 {
444 struct idetape_bh *bh = pc->bh;
445 int count;
446 unsigned int bcount = pc->xferred;
447
448 if (pc->flags & PC_FLAG_WRITING)
449 return;
450 while (bcount) {
451 if (bh == NULL) {
452 printk(KERN_ERR "ide-tape: bh == NULL in %s\n",
453 __func__);
454 return;
455 }
456 count = min((unsigned int)bh->b_size, (unsigned int)bcount);
457 atomic_set(&bh->b_count, count);
458 if (atomic_read(&bh->b_count) == bh->b_size)
459 bh = bh->b_reqnext;
460 bcount -= count;
461 }
462 pc->bh = bh;
463 }
464
465 /*
466 * idetape_next_pc_storage returns a pointer to a place in which we can
467 * safely store a packet command, even though we intend to leave the
468 * driver. A storage space for a maximum of IDETAPE_PC_STACK packet
469 * commands is allocated at initialization time.
470 */
471 static struct ide_atapi_pc *idetape_next_pc_storage(ide_drive_t *drive)
472 {
473 idetape_tape_t *tape = drive->driver_data;
474
475 debug_log(DBG_PCRQ_STACK, "pc_stack_index=%d\n", tape->pc_stack_index);
476
477 if (tape->pc_stack_index == IDETAPE_PC_STACK)
478 tape->pc_stack_index = 0;
479 return (&tape->pc_stack[tape->pc_stack_index++]);
480 }
481
482 /*
483 * idetape_next_rq_storage is used along with idetape_next_pc_storage.
484 * Since we queue packet commands in the request queue, we need to
485 * allocate a request, along with the allocation of a packet command.
486 */
487
488 /**************************************************************
489 * *
490 * This should get fixed to use kmalloc(.., GFP_ATOMIC) *
491 * followed later on by kfree(). -ml *
492 * *
493 **************************************************************/
494
495 static struct request *idetape_next_rq_storage(ide_drive_t *drive)
496 {
497 idetape_tape_t *tape = drive->driver_data;
498
499 debug_log(DBG_PCRQ_STACK, "rq_stack_index=%d\n", tape->rq_stack_index);
500
501 if (tape->rq_stack_index == IDETAPE_PC_STACK)
502 tape->rq_stack_index = 0;
503 return (&tape->rq_stack[tape->rq_stack_index++]);
504 }
505
506 /*
507 * called on each failed packet command retry to analyze the request sense. We
508 * currently do not utilize this information.
509 */
510 static void idetape_analyze_error(ide_drive_t *drive, u8 *sense)
511 {
512 idetape_tape_t *tape = drive->driver_data;
513 struct ide_atapi_pc *pc = tape->failed_pc;
514
515 tape->sense_key = sense[2] & 0xF;
516 tape->asc = sense[12];
517 tape->ascq = sense[13];
518
519 debug_log(DBG_ERR, "pc = %x, sense key = %x, asc = %x, ascq = %x\n",
520 pc->c[0], tape->sense_key, tape->asc, tape->ascq);
521
522 /* Correct pc->xferred by asking the tape. */
523 if (pc->flags & PC_FLAG_DMA_ERROR) {
524 pc->xferred = pc->req_xfer -
525 tape->blk_size *
526 get_unaligned_be32(&sense[3]);
527 idetape_update_buffers(pc);
528 }
529
530 /*
531 * If error was the result of a zero-length read or write command,
532 * with sense key=5, asc=0x22, ascq=0, let it slide. Some drives
533 * (i.e. Seagate STT3401A Travan) don't support 0-length read/writes.
534 */
535 if ((pc->c[0] == READ_6 || pc->c[0] == WRITE_6)
536 /* length == 0 */
537 && pc->c[4] == 0 && pc->c[3] == 0 && pc->c[2] == 0) {
538 if (tape->sense_key == 5) {
539 /* don't report an error, everything's ok */
540 pc->error = 0;
541 /* don't retry read/write */
542 pc->flags |= PC_FLAG_ABORT;
543 }
544 }
545 if (pc->c[0] == READ_6 && (sense[2] & 0x80)) {
546 pc->error = IDETAPE_ERROR_FILEMARK;
547 pc->flags |= PC_FLAG_ABORT;
548 }
549 if (pc->c[0] == WRITE_6) {
550 if ((sense[2] & 0x40) || (tape->sense_key == 0xd
551 && tape->asc == 0x0 && tape->ascq == 0x2)) {
552 pc->error = IDETAPE_ERROR_EOD;
553 pc->flags |= PC_FLAG_ABORT;
554 }
555 }
556 if (pc->c[0] == READ_6 || pc->c[0] == WRITE_6) {
557 if (tape->sense_key == 8) {
558 pc->error = IDETAPE_ERROR_EOD;
559 pc->flags |= PC_FLAG_ABORT;
560 }
561 if (!(pc->flags & PC_FLAG_ABORT) &&
562 pc->xferred)
563 pc->retries = IDETAPE_MAX_PC_RETRIES + 1;
564 }
565 }
566
567 /* Free data buffers completely. */
568 static void ide_tape_kfree_buffer(idetape_tape_t *tape)
569 {
570 struct idetape_bh *prev_bh, *bh = tape->merge_bh;
571
572 while (bh) {
573 u32 size = bh->b_size;
574
575 while (size) {
576 unsigned int order = fls(size >> PAGE_SHIFT)-1;
577
578 if (bh->b_data)
579 free_pages((unsigned long)bh->b_data, order);
580
581 size &= (order-1);
582 bh->b_data += (1 << order) * PAGE_SIZE;
583 }
584 prev_bh = bh;
585 bh = bh->b_reqnext;
586 kfree(prev_bh);
587 }
588 kfree(tape->merge_bh);
589 }
590
591 static int idetape_end_request(ide_drive_t *drive, int uptodate, int nr_sects)
592 {
593 struct request *rq = HWGROUP(drive)->rq;
594 idetape_tape_t *tape = drive->driver_data;
595 unsigned long flags;
596 int error;
597
598 debug_log(DBG_PROCS, "Enter %s\n", __func__);
599
600 switch (uptodate) {
601 case 0: error = IDETAPE_ERROR_GENERAL; break;
602 case 1: error = 0; break;
603 default: error = uptodate;
604 }
605 rq->errors = error;
606 if (error)
607 tape->failed_pc = NULL;
608
609 if (!blk_special_request(rq)) {
610 ide_end_request(drive, uptodate, nr_sects);
611 return 0;
612 }
613
614 spin_lock_irqsave(&tape->lock, flags);
615
616 ide_end_drive_cmd(drive, 0, 0);
617
618 spin_unlock_irqrestore(&tape->lock, flags);
619 return 0;
620 }
621
622 static void ide_tape_callback(ide_drive_t *drive)
623 {
624 idetape_tape_t *tape = drive->driver_data;
625 struct ide_atapi_pc *pc = tape->pc;
626 int uptodate = pc->error ? 0 : 1;
627
628 debug_log(DBG_PROCS, "Enter %s\n", __func__);
629
630 if (pc->c[0] == REQUEST_SENSE) {
631 if (uptodate)
632 idetape_analyze_error(drive, pc->buf);
633 else
634 printk(KERN_ERR "ide-tape: Error in REQUEST SENSE "
635 "itself - Aborting request!\n");
636 } else if (pc->c[0] == READ_6 || pc->c[0] == WRITE_6) {
637 struct request *rq = drive->hwif->hwgroup->rq;
638 int blocks = pc->xferred / tape->blk_size;
639
640 tape->avg_size += blocks * tape->blk_size;
641
642 if (time_after_eq(jiffies, tape->avg_time + HZ)) {
643 tape->avg_speed = tape->avg_size * HZ /
644 (jiffies - tape->avg_time) / 1024;
645 tape->avg_size = 0;
646 tape->avg_time = jiffies;
647 }
648
649 tape->first_frame += blocks;
650 rq->current_nr_sectors -= blocks;
651
652 if (pc->error)
653 uptodate = pc->error;
654 } else if (pc->c[0] == READ_POSITION && uptodate) {
655 u8 *readpos = tape->pc->buf;
656
657 debug_log(DBG_SENSE, "BOP - %s\n",
658 (readpos[0] & 0x80) ? "Yes" : "No");
659 debug_log(DBG_SENSE, "EOP - %s\n",
660 (readpos[0] & 0x40) ? "Yes" : "No");
661
662 if (readpos[0] & 0x4) {
663 printk(KERN_INFO "ide-tape: Block location is unknown"
664 "to the tape\n");
665 clear_bit(IDETAPE_FLAG_ADDRESS_VALID, &tape->flags);
666 uptodate = 0;
667 } else {
668 debug_log(DBG_SENSE, "Block Location - %u\n",
669 be32_to_cpu(*(u32 *)&readpos[4]));
670
671 tape->partition = readpos[1];
672 tape->first_frame = be32_to_cpu(*(u32 *)&readpos[4]);
673 set_bit(IDETAPE_FLAG_ADDRESS_VALID, &tape->flags);
674 }
675 }
676
677 idetape_end_request(drive, uptodate, 0);
678 }
679
680 static void idetape_init_pc(struct ide_atapi_pc *pc)
681 {
682 memset(pc->c, 0, 12);
683 pc->retries = 0;
684 pc->flags = 0;
685 pc->req_xfer = 0;
686 pc->buf = pc->pc_buf;
687 pc->buf_size = IDETAPE_PC_BUFFER_SIZE;
688 pc->bh = NULL;
689 pc->b_data = NULL;
690 pc->callback = ide_tape_callback;
691 }
692
693 static void idetape_create_request_sense_cmd(struct ide_atapi_pc *pc)
694 {
695 idetape_init_pc(pc);
696 pc->c[0] = REQUEST_SENSE;
697 pc->c[4] = 20;
698 pc->req_xfer = 20;
699 }
700
701 static void idetape_init_rq(struct request *rq, u8 cmd)
702 {
703 blk_rq_init(NULL, rq);
704 rq->cmd_type = REQ_TYPE_SPECIAL;
705 rq->cmd[0] = cmd;
706 }
707
708 /*
709 * Generate a new packet command request in front of the request queue, before
710 * the current request, so that it will be processed immediately, on the next
711 * pass through the driver. The function below is called from the request
712 * handling part of the driver (the "bottom" part). Safe storage for the request
713 * should be allocated with ide_tape_next_{pc,rq}_storage() prior to that.
714 *
715 * Memory for those requests is pre-allocated at initialization time, and is
716 * limited to IDETAPE_PC_STACK requests. We assume that we have enough space for
717 * the maximum possible number of inter-dependent packet commands.
718 *
719 * The higher level of the driver - The ioctl handler and the character device
720 * handling functions should queue request to the lower level part and wait for
721 * their completion using idetape_queue_pc_tail or idetape_queue_rw_tail.
722 */
723 static void idetape_queue_pc_head(ide_drive_t *drive, struct ide_atapi_pc *pc,
724 struct request *rq)
725 {
726 struct ide_tape_obj *tape = drive->driver_data;
727
728 idetape_init_rq(rq, REQ_IDETAPE_PC1);
729 rq->cmd_flags |= REQ_PREEMPT;
730 rq->buffer = (char *) pc;
731 rq->rq_disk = tape->disk;
732 ide_do_drive_cmd(drive, rq);
733 }
734
735 /*
736 * idetape_retry_pc is called when an error was detected during the
737 * last packet command. We queue a request sense packet command in
738 * the head of the request list.
739 */
740 static void idetape_retry_pc(ide_drive_t *drive)
741 {
742 idetape_tape_t *tape = drive->driver_data;
743 struct ide_atapi_pc *pc;
744 struct request *rq;
745
746 (void)ide_read_error(drive);
747 pc = idetape_next_pc_storage(drive);
748 rq = idetape_next_rq_storage(drive);
749 idetape_create_request_sense_cmd(pc);
750 set_bit(IDETAPE_FLAG_IGNORE_DSC, &tape->flags);
751 idetape_queue_pc_head(drive, pc, rq);
752 }
753
754 /*
755 * Postpone the current request so that ide.c will be able to service requests
756 * from another device on the same hwgroup while we are polling for DSC.
757 */
758 static void idetape_postpone_request(ide_drive_t *drive)
759 {
760 idetape_tape_t *tape = drive->driver_data;
761
762 debug_log(DBG_PROCS, "Enter %s\n", __func__);
763
764 tape->postponed_rq = HWGROUP(drive)->rq;
765 ide_stall_queue(drive, tape->dsc_poll_freq);
766 }
767
768 typedef void idetape_io_buf(ide_drive_t *, struct ide_atapi_pc *, unsigned int);
769
770 /*
771 * This is the usual interrupt handler which will be called during a packet
772 * command. We will transfer some of the data (as requested by the drive) and
773 * will re-point interrupt handler to us. When data transfer is finished, we
774 * will act according to the algorithm described before
775 * idetape_issue_pc.
776 */
777 static ide_startstop_t idetape_pc_intr(ide_drive_t *drive)
778 {
779 ide_hwif_t *hwif = drive->hwif;
780 idetape_tape_t *tape = drive->driver_data;
781 struct ide_atapi_pc *pc = tape->pc;
782 xfer_func_t *xferfunc;
783 idetape_io_buf *iobuf;
784 unsigned int temp;
785 u16 bcount;
786 u8 stat, ireason;
787
788 debug_log(DBG_PROCS, "Enter %s - interrupt handler\n", __func__);
789
790 /* Clear the interrupt */
791 stat = ide_read_status(drive);
792
793 if (pc->flags & PC_FLAG_DMA_IN_PROGRESS) {
794 if (hwif->dma_ops->dma_end(drive) || (stat & ERR_STAT)) {
795 pc->flags |= PC_FLAG_DMA_ERROR;
796 } else {
797 pc->xferred = pc->req_xfer;
798 idetape_update_buffers(pc);
799 }
800 debug_log(DBG_PROCS, "DMA finished\n");
801
802 }
803
804 /* No more interrupts */
805 if ((stat & DRQ_STAT) == 0) {
806 debug_log(DBG_SENSE, "Packet command completed, %d bytes"
807 " transferred\n", pc->xferred);
808
809 pc->flags &= ~PC_FLAG_DMA_IN_PROGRESS;
810 local_irq_enable_in_hardirq();
811
812 if ((stat & ERR_STAT) && pc->c[0] == REQUEST_SENSE)
813 stat &= ~ERR_STAT;
814 if ((stat & ERR_STAT) || (pc->flags & PC_FLAG_DMA_ERROR)) {
815 /* Error detected */
816 debug_log(DBG_ERR, "%s: I/O error\n", tape->name);
817
818 if (pc->c[0] == REQUEST_SENSE) {
819 printk(KERN_ERR "%s: I/O error in request sense"
820 " command\n", drive->name);
821 return ide_do_reset(drive);
822 }
823 debug_log(DBG_ERR, "[cmd %x]: check condition\n",
824 pc->c[0]);
825
826 /* Retry operation */
827 idetape_retry_pc(drive);
828 return ide_stopped;
829 }
830 pc->error = 0;
831 if ((pc->flags & PC_FLAG_WAIT_FOR_DSC) &&
832 (stat & SEEK_STAT) == 0) {
833 /* Media access command */
834 tape->dsc_polling_start = jiffies;
835 tape->dsc_poll_freq = IDETAPE_DSC_MA_FAST;
836 tape->dsc_timeout = jiffies + IDETAPE_DSC_MA_TIMEOUT;
837 /* Allow ide.c to handle other requests */
838 idetape_postpone_request(drive);
839 return ide_stopped;
840 }
841 if (tape->failed_pc == pc)
842 tape->failed_pc = NULL;
843 /* Command finished - Call the callback function */
844 pc->callback(drive);
845 return ide_stopped;
846 }
847
848 if (pc->flags & PC_FLAG_DMA_IN_PROGRESS) {
849 pc->flags &= ~PC_FLAG_DMA_IN_PROGRESS;
850 printk(KERN_ERR "%s: The device wants to issue more interrupts "
851 "in DMA mode\n", drive->name);
852 ide_dma_off(drive);
853 return ide_do_reset(drive);
854 }
855 /* Get the number of bytes to transfer on this interrupt. */
856 bcount = (hwif->INB(hwif->io_ports.lbah_addr) << 8) |
857 hwif->INB(hwif->io_ports.lbam_addr);
858
859 ireason = hwif->INB(hwif->io_ports.nsect_addr);
860
861 if (ireason & CD) {
862 printk(KERN_ERR "%s: CoD != 0 in %s\n", drive->name, __func__);
863 return ide_do_reset(drive);
864 }
865 if (((ireason & IO) == IO) == !!(pc->flags & PC_FLAG_WRITING)) {
866 /* Hopefully, we will never get here */
867 printk(KERN_ERR "%s: We wanted to %s, but the device wants us "
868 "to %s!\n", drive->name,
869 (ireason & IO) ? "Write" : "Read",
870 (ireason & IO) ? "Read" : "Write");
871 return ide_do_reset(drive);
872 }
873 if (!(pc->flags & PC_FLAG_WRITING)) {
874 /* Reading - Check that we have enough space */
875 temp = pc->xferred + bcount;
876 if (temp > pc->req_xfer) {
877 if (temp > pc->buf_size) {
878 printk(KERN_ERR "%s: The device wants to send "
879 "us more data than expected - "
880 "discarding data\n",
881 drive->name);
882 ide_pad_transfer(drive, 0, bcount);
883 ide_set_handler(drive, &idetape_pc_intr,
884 IDETAPE_WAIT_CMD, NULL);
885 return ide_started;
886 }
887 debug_log(DBG_SENSE, "The device wants to send us more "
888 "data than expected - allowing transfer\n");
889 }
890 iobuf = &idetape_input_buffers;
891 xferfunc = hwif->input_data;
892 } else {
893 iobuf = &idetape_output_buffers;
894 xferfunc = hwif->output_data;
895 }
896
897 if (pc->bh)
898 iobuf(drive, pc, bcount);
899 else
900 xferfunc(drive, NULL, pc->cur_pos, bcount);
901
902 /* Update the current position */
903 pc->xferred += bcount;
904 pc->cur_pos += bcount;
905
906 debug_log(DBG_SENSE, "[cmd %x] transferred %d bytes on that intr.\n",
907 pc->c[0], bcount);
908
909 /* And set the interrupt handler again */
910 ide_set_handler(drive, &idetape_pc_intr, IDETAPE_WAIT_CMD, NULL);
911 return ide_started;
912 }
913
914 /*
915 * Packet Command Interface
916 *
917 * The current Packet Command is available in tape->pc, and will not change
918 * until we finish handling it. Each packet command is associated with a
919 * callback function that will be called when the command is finished.
920 *
921 * The handling will be done in three stages:
922 *
923 * 1. idetape_issue_pc will send the packet command to the drive, and will set
924 * the interrupt handler to idetape_pc_intr.
925 *
926 * 2. On each interrupt, idetape_pc_intr will be called. This step will be
927 * repeated until the device signals us that no more interrupts will be issued.
928 *
929 * 3. ATAPI Tape media access commands have immediate status with a delayed
930 * process. In case of a successful initiation of a media access packet command,
931 * the DSC bit will be set when the actual execution of the command is finished.
932 * Since the tape drive will not issue an interrupt, we have to poll for this
933 * event. In this case, we define the request as "low priority request" by
934 * setting rq_status to IDETAPE_RQ_POSTPONED, set a timer to poll for DSC and
935 * exit the driver.
936 *
937 * ide.c will then give higher priority to requests which originate from the
938 * other device, until will change rq_status to RQ_ACTIVE.
939 *
940 * 4. When the packet command is finished, it will be checked for errors.
941 *
942 * 5. In case an error was found, we queue a request sense packet command in
943 * front of the request queue and retry the operation up to
944 * IDETAPE_MAX_PC_RETRIES times.
945 *
946 * 6. In case no error was found, or we decided to give up and not to retry
947 * again, the callback function will be called and then we will handle the next
948 * request.
949 */
950 static ide_startstop_t idetape_transfer_pc(ide_drive_t *drive)
951 {
952 ide_hwif_t *hwif = drive->hwif;
953 idetape_tape_t *tape = drive->driver_data;
954 struct ide_atapi_pc *pc = tape->pc;
955 int retries = 100;
956 ide_startstop_t startstop;
957 u8 ireason;
958
959 if (ide_wait_stat(&startstop, drive, DRQ_STAT, BUSY_STAT, WAIT_READY)) {
960 printk(KERN_ERR "%s: Strange, packet command initiated yet "
961 "DRQ isn't asserted\n", drive->name);
962 return startstop;
963 }
964 ireason = hwif->INB(hwif->io_ports.nsect_addr);
965 while (retries-- && ((ireason & CD) == 0 || (ireason & IO))) {
966 printk(KERN_ERR "%s: (IO,CoD != (0,1) while issuing "
967 "a packet command, retrying\n", drive->name);
968 udelay(100);
969 ireason = hwif->INB(hwif->io_ports.nsect_addr);
970 if (retries == 0) {
971 printk(KERN_ERR "%s: (IO,CoD != (0,1) while issuing "
972 "a packet command, ignoring\n",
973 drive->name);
974 ireason |= CD;
975 ireason &= ~IO;
976 }
977 }
978 if ((ireason & CD) == 0 || (ireason & IO)) {
979 printk(KERN_ERR "%s: (IO,CoD) != (0,1) while issuing "
980 "a packet command\n", drive->name);
981 return ide_do_reset(drive);
982 }
983 /* Set the interrupt routine */
984 ide_set_handler(drive, &idetape_pc_intr, IDETAPE_WAIT_CMD, NULL);
985
986 /* Begin DMA, if necessary */
987 if (pc->flags & PC_FLAG_DMA_IN_PROGRESS)
988 hwif->dma_ops->dma_start(drive);
989
990 /* Send the actual packet */
991 hwif->output_data(drive, NULL, pc->c, 12);
992
993 return ide_started;
994 }
995
996 static ide_startstop_t idetape_issue_pc(ide_drive_t *drive,
997 struct ide_atapi_pc *pc)
998 {
999 ide_hwif_t *hwif = drive->hwif;
1000 idetape_tape_t *tape = drive->driver_data;
1001 int dma_ok = 0;
1002 u16 bcount;
1003
1004 if (tape->pc->c[0] == REQUEST_SENSE &&
1005 pc->c[0] == REQUEST_SENSE) {
1006 printk(KERN_ERR "ide-tape: possible ide-tape.c bug - "
1007 "Two request sense in serial were issued\n");
1008 }
1009
1010 if (tape->failed_pc == NULL && pc->c[0] != REQUEST_SENSE)
1011 tape->failed_pc = pc;
1012 /* Set the current packet command */
1013 tape->pc = pc;
1014
1015 if (pc->retries > IDETAPE_MAX_PC_RETRIES ||
1016 (pc->flags & PC_FLAG_ABORT)) {
1017 /*
1018 * We will "abort" retrying a packet command in case legitimate
1019 * error code was received (crossing a filemark, or end of the
1020 * media, for example).
1021 */
1022 if (!(pc->flags & PC_FLAG_ABORT)) {
1023 if (!(pc->c[0] == TEST_UNIT_READY &&
1024 tape->sense_key == 2 && tape->asc == 4 &&
1025 (tape->ascq == 1 || tape->ascq == 8))) {
1026 printk(KERN_ERR "ide-tape: %s: I/O error, "
1027 "pc = %2x, key = %2x, "
1028 "asc = %2x, ascq = %2x\n",
1029 tape->name, pc->c[0],
1030 tape->sense_key, tape->asc,
1031 tape->ascq);
1032 }
1033 /* Giving up */
1034 pc->error = IDETAPE_ERROR_GENERAL;
1035 }
1036 tape->failed_pc = NULL;
1037 pc->callback(drive);
1038 return ide_stopped;
1039 }
1040 debug_log(DBG_SENSE, "Retry #%d, cmd = %02X\n", pc->retries, pc->c[0]);
1041
1042 pc->retries++;
1043 /* We haven't transferred any data yet */
1044 pc->xferred = 0;
1045 pc->cur_pos = pc->buf;
1046 /* Request to transfer the entire buffer at once */
1047 bcount = pc->req_xfer;
1048
1049 if (pc->flags & PC_FLAG_DMA_ERROR) {
1050 pc->flags &= ~PC_FLAG_DMA_ERROR;
1051 ide_dma_off(drive);
1052 }
1053 if ((pc->flags & PC_FLAG_DMA_OK) && drive->using_dma)
1054 dma_ok = !hwif->dma_ops->dma_setup(drive);
1055
1056 ide_pktcmd_tf_load(drive, IDE_TFLAG_OUT_DEVICE, bcount, dma_ok);
1057
1058 if (dma_ok)
1059 /* Will begin DMA later */
1060 pc->flags |= PC_FLAG_DMA_IN_PROGRESS;
1061 if (test_bit(IDETAPE_FLAG_DRQ_INTERRUPT, &tape->flags)) {
1062 ide_execute_command(drive, WIN_PACKETCMD, &idetape_transfer_pc,
1063 IDETAPE_WAIT_CMD, NULL);
1064 return ide_started;
1065 } else {
1066 ide_execute_pkt_cmd(drive);
1067 return idetape_transfer_pc(drive);
1068 }
1069 }
1070
1071 /* A mode sense command is used to "sense" tape parameters. */
1072 static void idetape_create_mode_sense_cmd(struct ide_atapi_pc *pc, u8 page_code)
1073 {
1074 idetape_init_pc(pc);
1075 pc->c[0] = MODE_SENSE;
1076 if (page_code != IDETAPE_BLOCK_DESCRIPTOR)
1077 /* DBD = 1 - Don't return block descriptors */
1078 pc->c[1] = 8;
1079 pc->c[2] = page_code;
1080 /*
1081 * Changed pc->c[3] to 0 (255 will at best return unused info).
1082 *
1083 * For SCSI this byte is defined as subpage instead of high byte
1084 * of length and some IDE drives seem to interpret it this way
1085 * and return an error when 255 is used.
1086 */
1087 pc->c[3] = 0;
1088 /* We will just discard data in that case */
1089 pc->c[4] = 255;
1090 if (page_code == IDETAPE_BLOCK_DESCRIPTOR)
1091 pc->req_xfer = 12;
1092 else if (page_code == IDETAPE_CAPABILITIES_PAGE)
1093 pc->req_xfer = 24;
1094 else
1095 pc->req_xfer = 50;
1096 }
1097
1098 static ide_startstop_t idetape_media_access_finished(ide_drive_t *drive)
1099 {
1100 idetape_tape_t *tape = drive->driver_data;
1101 struct ide_atapi_pc *pc = tape->pc;
1102 u8 stat;
1103
1104 stat = ide_read_status(drive);
1105
1106 if (stat & SEEK_STAT) {
1107 if (stat & ERR_STAT) {
1108 /* Error detected */
1109 if (pc->c[0] != TEST_UNIT_READY)
1110 printk(KERN_ERR "ide-tape: %s: I/O error, ",
1111 tape->name);
1112 /* Retry operation */
1113 idetape_retry_pc(drive);
1114 return ide_stopped;
1115 }
1116 pc->error = 0;
1117 if (tape->failed_pc == pc)
1118 tape->failed_pc = NULL;
1119 } else {
1120 pc->error = IDETAPE_ERROR_GENERAL;
1121 tape->failed_pc = NULL;
1122 }
1123 pc->callback(drive);
1124 return ide_stopped;
1125 }
1126
1127 static void idetape_create_read_cmd(idetape_tape_t *tape,
1128 struct ide_atapi_pc *pc,
1129 unsigned int length, struct idetape_bh *bh)
1130 {
1131 idetape_init_pc(pc);
1132 pc->c[0] = READ_6;
1133 put_unaligned(cpu_to_be32(length), (unsigned int *) &pc->c[1]);
1134 pc->c[1] = 1;
1135 pc->bh = bh;
1136 atomic_set(&bh->b_count, 0);
1137 pc->buf = NULL;
1138 pc->buf_size = length * tape->blk_size;
1139 pc->req_xfer = pc->buf_size;
1140 if (pc->req_xfer == tape->buffer_size)
1141 pc->flags |= PC_FLAG_DMA_OK;
1142 }
1143
1144 static void idetape_create_write_cmd(idetape_tape_t *tape,
1145 struct ide_atapi_pc *pc,
1146 unsigned int length, struct idetape_bh *bh)
1147 {
1148 idetape_init_pc(pc);
1149 pc->c[0] = WRITE_6;
1150 put_unaligned(cpu_to_be32(length), (unsigned int *) &pc->c[1]);
1151 pc->c[1] = 1;
1152 pc->flags |= PC_FLAG_WRITING;
1153 pc->bh = bh;
1154 pc->b_data = bh->b_data;
1155 pc->b_count = atomic_read(&bh->b_count);
1156 pc->buf = NULL;
1157 pc->buf_size = length * tape->blk_size;
1158 pc->req_xfer = pc->buf_size;
1159 if (pc->req_xfer == tape->buffer_size)
1160 pc->flags |= PC_FLAG_DMA_OK;
1161 }
1162
1163 static ide_startstop_t idetape_do_request(ide_drive_t *drive,
1164 struct request *rq, sector_t block)
1165 {
1166 idetape_tape_t *tape = drive->driver_data;
1167 struct ide_atapi_pc *pc = NULL;
1168 struct request *postponed_rq = tape->postponed_rq;
1169 u8 stat;
1170
1171 debug_log(DBG_SENSE, "sector: %ld, nr_sectors: %ld,"
1172 " current_nr_sectors: %d\n",
1173 rq->sector, rq->nr_sectors, rq->current_nr_sectors);
1174
1175 if (!blk_special_request(rq)) {
1176 /* We do not support buffer cache originated requests. */
1177 printk(KERN_NOTICE "ide-tape: %s: Unsupported request in "
1178 "request queue (%d)\n", drive->name, rq->cmd_type);
1179 ide_end_request(drive, 0, 0);
1180 return ide_stopped;
1181 }
1182
1183 /* Retry a failed packet command */
1184 if (tape->failed_pc && tape->pc->c[0] == REQUEST_SENSE)
1185 return idetape_issue_pc(drive, tape->failed_pc);
1186
1187 if (postponed_rq != NULL)
1188 if (rq != postponed_rq) {
1189 printk(KERN_ERR "ide-tape: ide-tape.c bug - "
1190 "Two DSC requests were queued\n");
1191 idetape_end_request(drive, 0, 0);
1192 return ide_stopped;
1193 }
1194
1195 tape->postponed_rq = NULL;
1196
1197 /*
1198 * If the tape is still busy, postpone our request and service
1199 * the other device meanwhile.
1200 */
1201 stat = ide_read_status(drive);
1202
1203 if (!drive->dsc_overlap && !(rq->cmd[0] & REQ_IDETAPE_PC2))
1204 set_bit(IDETAPE_FLAG_IGNORE_DSC, &tape->flags);
1205
1206 if (drive->post_reset == 1) {
1207 set_bit(IDETAPE_FLAG_IGNORE_DSC, &tape->flags);
1208 drive->post_reset = 0;
1209 }
1210
1211 if (!test_and_clear_bit(IDETAPE_FLAG_IGNORE_DSC, &tape->flags) &&
1212 (stat & SEEK_STAT) == 0) {
1213 if (postponed_rq == NULL) {
1214 tape->dsc_polling_start = jiffies;
1215 tape->dsc_poll_freq = tape->best_dsc_rw_freq;
1216 tape->dsc_timeout = jiffies + IDETAPE_DSC_RW_TIMEOUT;
1217 } else if (time_after(jiffies, tape->dsc_timeout)) {
1218 printk(KERN_ERR "ide-tape: %s: DSC timeout\n",
1219 tape->name);
1220 if (rq->cmd[0] & REQ_IDETAPE_PC2) {
1221 idetape_media_access_finished(drive);
1222 return ide_stopped;
1223 } else {
1224 return ide_do_reset(drive);
1225 }
1226 } else if (time_after(jiffies,
1227 tape->dsc_polling_start +
1228 IDETAPE_DSC_MA_THRESHOLD))
1229 tape->dsc_poll_freq = IDETAPE_DSC_MA_SLOW;
1230 idetape_postpone_request(drive);
1231 return ide_stopped;
1232 }
1233 if (rq->cmd[0] & REQ_IDETAPE_READ) {
1234 pc = idetape_next_pc_storage(drive);
1235 idetape_create_read_cmd(tape, pc, rq->current_nr_sectors,
1236 (struct idetape_bh *)rq->special);
1237 goto out;
1238 }
1239 if (rq->cmd[0] & REQ_IDETAPE_WRITE) {
1240 pc = idetape_next_pc_storage(drive);
1241 idetape_create_write_cmd(tape, pc, rq->current_nr_sectors,
1242 (struct idetape_bh *)rq->special);
1243 goto out;
1244 }
1245 if (rq->cmd[0] & REQ_IDETAPE_PC1) {
1246 pc = (struct ide_atapi_pc *) rq->buffer;
1247 rq->cmd[0] &= ~(REQ_IDETAPE_PC1);
1248 rq->cmd[0] |= REQ_IDETAPE_PC2;
1249 goto out;
1250 }
1251 if (rq->cmd[0] & REQ_IDETAPE_PC2) {
1252 idetape_media_access_finished(drive);
1253 return ide_stopped;
1254 }
1255 BUG();
1256 out:
1257 return idetape_issue_pc(drive, pc);
1258 }
1259
1260 /*
1261 * The function below uses __get_free_pages to allocate a data buffer of size
1262 * tape->buffer_size (or a bit more). We attempt to combine sequential pages as
1263 * much as possible.
1264 *
1265 * It returns a pointer to the newly allocated buffer, or NULL in case of
1266 * failure.
1267 */
1268 static struct idetape_bh *ide_tape_kmalloc_buffer(idetape_tape_t *tape,
1269 int full, int clear)
1270 {
1271 struct idetape_bh *prev_bh, *bh, *merge_bh;
1272 int pages = tape->pages_per_buffer;
1273 unsigned int order, b_allocd;
1274 char *b_data = NULL;
1275
1276 merge_bh = kmalloc(sizeof(struct idetape_bh), GFP_KERNEL);
1277 bh = merge_bh;
1278 if (bh == NULL)
1279 goto abort;
1280
1281 order = fls(pages) - 1;
1282 bh->b_data = (char *) __get_free_pages(GFP_KERNEL, order);
1283 if (!bh->b_data)
1284 goto abort;
1285 b_allocd = (1 << order) * PAGE_SIZE;
1286 pages &= (order-1);
1287
1288 if (clear)
1289 memset(bh->b_data, 0, b_allocd);
1290 bh->b_reqnext = NULL;
1291 bh->b_size = b_allocd;
1292 atomic_set(&bh->b_count, full ? bh->b_size : 0);
1293
1294 while (pages) {
1295 order = fls(pages) - 1;
1296 b_data = (char *) __get_free_pages(GFP_KERNEL, order);
1297 if (!b_data)
1298 goto abort;
1299 b_allocd = (1 << order) * PAGE_SIZE;
1300
1301 if (clear)
1302 memset(b_data, 0, b_allocd);
1303
1304 /* newly allocated page frames below buffer header or ...*/
1305 if (bh->b_data == b_data + b_allocd) {
1306 bh->b_size += b_allocd;
1307 bh->b_data -= b_allocd;
1308 if (full)
1309 atomic_add(b_allocd, &bh->b_count);
1310 continue;
1311 }
1312 /* they are above the header */
1313 if (b_data == bh->b_data + bh->b_size) {
1314 bh->b_size += b_allocd;
1315 if (full)
1316 atomic_add(b_allocd, &bh->b_count);
1317 continue;
1318 }
1319 prev_bh = bh;
1320 bh = kmalloc(sizeof(struct idetape_bh), GFP_KERNEL);
1321 if (!bh) {
1322 free_pages((unsigned long) b_data, order);
1323 goto abort;
1324 }
1325 bh->b_reqnext = NULL;
1326 bh->b_data = b_data;
1327 bh->b_size = b_allocd;
1328 atomic_set(&bh->b_count, full ? bh->b_size : 0);
1329 prev_bh->b_reqnext = bh;
1330
1331 pages &= (order-1);
1332 }
1333
1334 bh->b_size -= tape->excess_bh_size;
1335 if (full)
1336 atomic_sub(tape->excess_bh_size, &bh->b_count);
1337 return merge_bh;
1338 abort:
1339 ide_tape_kfree_buffer(tape);
1340 return NULL;
1341 }
1342
1343 static int idetape_copy_stage_from_user(idetape_tape_t *tape,
1344 const char __user *buf, int n)
1345 {
1346 struct idetape_bh *bh = tape->bh;
1347 int count;
1348 int ret = 0;
1349
1350 while (n) {
1351 if (bh == NULL) {
1352 printk(KERN_ERR "ide-tape: bh == NULL in %s\n",
1353 __func__);
1354 return 1;
1355 }
1356 count = min((unsigned int)
1357 (bh->b_size - atomic_read(&bh->b_count)),
1358 (unsigned int)n);
1359 if (copy_from_user(bh->b_data + atomic_read(&bh->b_count), buf,
1360 count))
1361 ret = 1;
1362 n -= count;
1363 atomic_add(count, &bh->b_count);
1364 buf += count;
1365 if (atomic_read(&bh->b_count) == bh->b_size) {
1366 bh = bh->b_reqnext;
1367 if (bh)
1368 atomic_set(&bh->b_count, 0);
1369 }
1370 }
1371 tape->bh = bh;
1372 return ret;
1373 }
1374
1375 static int idetape_copy_stage_to_user(idetape_tape_t *tape, char __user *buf,
1376 int n)
1377 {
1378 struct idetape_bh *bh = tape->bh;
1379 int count;
1380 int ret = 0;
1381
1382 while (n) {
1383 if (bh == NULL) {
1384 printk(KERN_ERR "ide-tape: bh == NULL in %s\n",
1385 __func__);
1386 return 1;
1387 }
1388 count = min(tape->b_count, n);
1389 if (copy_to_user(buf, tape->b_data, count))
1390 ret = 1;
1391 n -= count;
1392 tape->b_data += count;
1393 tape->b_count -= count;
1394 buf += count;
1395 if (!tape->b_count) {
1396 bh = bh->b_reqnext;
1397 tape->bh = bh;
1398 if (bh) {
1399 tape->b_data = bh->b_data;
1400 tape->b_count = atomic_read(&bh->b_count);
1401 }
1402 }
1403 }
1404 return ret;
1405 }
1406
1407 static void idetape_init_merge_buffer(idetape_tape_t *tape)
1408 {
1409 struct idetape_bh *bh = tape->merge_bh;
1410 tape->bh = tape->merge_bh;
1411
1412 if (tape->chrdev_dir == IDETAPE_DIR_WRITE)
1413 atomic_set(&bh->b_count, 0);
1414 else {
1415 tape->b_data = bh->b_data;
1416 tape->b_count = atomic_read(&bh->b_count);
1417 }
1418 }
1419
1420 /*
1421 * Write a filemark if write_filemark=1. Flush the device buffers without
1422 * writing a filemark otherwise.
1423 */
1424 static void idetape_create_write_filemark_cmd(ide_drive_t *drive,
1425 struct ide_atapi_pc *pc, int write_filemark)
1426 {
1427 idetape_init_pc(pc);
1428 pc->c[0] = WRITE_FILEMARKS;
1429 pc->c[4] = write_filemark;
1430 pc->flags |= PC_FLAG_WAIT_FOR_DSC;
1431 }
1432
1433 static void idetape_create_test_unit_ready_cmd(struct ide_atapi_pc *pc)
1434 {
1435 idetape_init_pc(pc);
1436 pc->c[0] = TEST_UNIT_READY;
1437 }
1438
1439 /*
1440 * We add a special packet command request to the tail of the request queue, and
1441 * wait for it to be serviced. This is not to be called from within the request
1442 * handling part of the driver! We allocate here data on the stack and it is
1443 * valid until the request is finished. This is not the case for the bottom part
1444 * of the driver, where we are always leaving the functions to wait for an
1445 * interrupt or a timer event.
1446 *
1447 * From the bottom part of the driver, we should allocate safe memory using
1448 * idetape_next_pc_storage() and ide_tape_next_rq_storage(), and add the request
1449 * to the request list without waiting for it to be serviced! In that case, we
1450 * usually use idetape_queue_pc_head().
1451 */
1452 static int idetape_queue_pc_tail(ide_drive_t *drive, struct ide_atapi_pc *pc)
1453 {
1454 struct ide_tape_obj *tape = drive->driver_data;
1455 struct request *rq;
1456 int error;
1457
1458 rq = blk_get_request(drive->queue, READ, __GFP_WAIT);
1459 rq->cmd_type = REQ_TYPE_SPECIAL;
1460 rq->cmd[0] = REQ_IDETAPE_PC1;
1461 rq->buffer = (char *)pc;
1462 error = blk_execute_rq(drive->queue, tape->disk, rq, 0);
1463 blk_put_request(rq);
1464 return error;
1465 }
1466
1467 static void idetape_create_load_unload_cmd(ide_drive_t *drive,
1468 struct ide_atapi_pc *pc, int cmd)
1469 {
1470 idetape_init_pc(pc);
1471 pc->c[0] = START_STOP;
1472 pc->c[4] = cmd;
1473 pc->flags |= PC_FLAG_WAIT_FOR_DSC;
1474 }
1475
1476 static int idetape_wait_ready(ide_drive_t *drive, unsigned long timeout)
1477 {
1478 idetape_tape_t *tape = drive->driver_data;
1479 struct ide_atapi_pc pc;
1480 int load_attempted = 0;
1481
1482 /* Wait for the tape to become ready */
1483 set_bit(IDETAPE_FLAG_MEDIUM_PRESENT, &tape->flags);
1484 timeout += jiffies;
1485 while (time_before(jiffies, timeout)) {
1486 idetape_create_test_unit_ready_cmd(&pc);
1487 if (!idetape_queue_pc_tail(drive, &pc))
1488 return 0;
1489 if ((tape->sense_key == 2 && tape->asc == 4 && tape->ascq == 2)
1490 || (tape->asc == 0x3A)) {
1491 /* no media */
1492 if (load_attempted)
1493 return -ENOMEDIUM;
1494 idetape_create_load_unload_cmd(drive, &pc,
1495 IDETAPE_LU_LOAD_MASK);
1496 idetape_queue_pc_tail(drive, &pc);
1497 load_attempted = 1;
1498 /* not about to be ready */
1499 } else if (!(tape->sense_key == 2 && tape->asc == 4 &&
1500 (tape->ascq == 1 || tape->ascq == 8)))
1501 return -EIO;
1502 msleep(100);
1503 }
1504 return -EIO;
1505 }
1506
1507 static int idetape_flush_tape_buffers(ide_drive_t *drive)
1508 {
1509 struct ide_atapi_pc pc;
1510 int rc;
1511
1512 idetape_create_write_filemark_cmd(drive, &pc, 0);
1513 rc = idetape_queue_pc_tail(drive, &pc);
1514 if (rc)
1515 return rc;
1516 idetape_wait_ready(drive, 60 * 5 * HZ);
1517 return 0;
1518 }
1519
1520 static void idetape_create_read_position_cmd(struct ide_atapi_pc *pc)
1521 {
1522 idetape_init_pc(pc);
1523 pc->c[0] = READ_POSITION;
1524 pc->req_xfer = 20;
1525 }
1526
1527 static int idetape_read_position(ide_drive_t *drive)
1528 {
1529 idetape_tape_t *tape = drive->driver_data;
1530 struct ide_atapi_pc pc;
1531 int position;
1532
1533 debug_log(DBG_PROCS, "Enter %s\n", __func__);
1534
1535 idetape_create_read_position_cmd(&pc);
1536 if (idetape_queue_pc_tail(drive, &pc))
1537 return -1;
1538 position = tape->first_frame;
1539 return position;
1540 }
1541
1542 static void idetape_create_locate_cmd(ide_drive_t *drive,
1543 struct ide_atapi_pc *pc,
1544 unsigned int block, u8 partition, int skip)
1545 {
1546 idetape_init_pc(pc);
1547 pc->c[0] = POSITION_TO_ELEMENT;
1548 pc->c[1] = 2;
1549 put_unaligned(cpu_to_be32(block), (unsigned int *) &pc->c[3]);
1550 pc->c[8] = partition;
1551 pc->flags |= PC_FLAG_WAIT_FOR_DSC;
1552 }
1553
1554 static int idetape_create_prevent_cmd(ide_drive_t *drive,
1555 struct ide_atapi_pc *pc, int prevent)
1556 {
1557 idetape_tape_t *tape = drive->driver_data;
1558
1559 /* device supports locking according to capabilities page */
1560 if (!(tape->caps[6] & 0x01))
1561 return 0;
1562
1563 idetape_init_pc(pc);
1564 pc->c[0] = ALLOW_MEDIUM_REMOVAL;
1565 pc->c[4] = prevent;
1566 return 1;
1567 }
1568
1569 static void __ide_tape_discard_merge_buffer(ide_drive_t *drive)
1570 {
1571 idetape_tape_t *tape = drive->driver_data;
1572
1573 if (tape->chrdev_dir != IDETAPE_DIR_READ)
1574 return;
1575
1576 clear_bit(IDETAPE_FLAG_FILEMARK, &tape->flags);
1577 tape->merge_bh_size = 0;
1578 if (tape->merge_bh != NULL) {
1579 ide_tape_kfree_buffer(tape);
1580 tape->merge_bh = NULL;
1581 }
1582
1583 tape->chrdev_dir = IDETAPE_DIR_NONE;
1584 }
1585
1586 /*
1587 * Position the tape to the requested block using the LOCATE packet command.
1588 * A READ POSITION command is then issued to check where we are positioned. Like
1589 * all higher level operations, we queue the commands at the tail of the request
1590 * queue and wait for their completion.
1591 */
1592 static int idetape_position_tape(ide_drive_t *drive, unsigned int block,
1593 u8 partition, int skip)
1594 {
1595 idetape_tape_t *tape = drive->driver_data;
1596 int retval;
1597 struct ide_atapi_pc pc;
1598
1599 if (tape->chrdev_dir == IDETAPE_DIR_READ)
1600 __ide_tape_discard_merge_buffer(drive);
1601 idetape_wait_ready(drive, 60 * 5 * HZ);
1602 idetape_create_locate_cmd(drive, &pc, block, partition, skip);
1603 retval = idetape_queue_pc_tail(drive, &pc);
1604 if (retval)
1605 return (retval);
1606
1607 idetape_create_read_position_cmd(&pc);
1608 return (idetape_queue_pc_tail(drive, &pc));
1609 }
1610
1611 static void ide_tape_discard_merge_buffer(ide_drive_t *drive,
1612 int restore_position)
1613 {
1614 idetape_tape_t *tape = drive->driver_data;
1615 int seek, position;
1616
1617 __ide_tape_discard_merge_buffer(drive);
1618 if (restore_position) {
1619 position = idetape_read_position(drive);
1620 seek = position > 0 ? position : 0;
1621 if (idetape_position_tape(drive, seek, 0, 0)) {
1622 printk(KERN_INFO "ide-tape: %s: position_tape failed in"
1623 " %s\n", tape->name, __func__);
1624 return;
1625 }
1626 }
1627 }
1628
1629 /*
1630 * Generate a read/write request for the block device interface and wait for it
1631 * to be serviced.
1632 */
1633 static int idetape_queue_rw_tail(ide_drive_t *drive, int cmd, int blocks,
1634 struct idetape_bh *bh)
1635 {
1636 idetape_tape_t *tape = drive->driver_data;
1637 struct request *rq;
1638 int ret, errors;
1639
1640 debug_log(DBG_SENSE, "%s: cmd=%d\n", __func__, cmd);
1641
1642 rq = blk_get_request(drive->queue, READ, __GFP_WAIT);
1643 rq->cmd_type = REQ_TYPE_SPECIAL;
1644 rq->cmd[0] = cmd;
1645 rq->rq_disk = tape->disk;
1646 rq->special = (void *)bh;
1647 rq->sector = tape->first_frame;
1648 rq->nr_sectors = blocks;
1649 rq->current_nr_sectors = blocks;
1650 blk_execute_rq(drive->queue, tape->disk, rq, 0);
1651
1652 errors = rq->errors;
1653 ret = tape->blk_size * (blocks - rq->current_nr_sectors);
1654 blk_put_request(rq);
1655
1656 if ((cmd & (REQ_IDETAPE_READ | REQ_IDETAPE_WRITE)) == 0)
1657 return 0;
1658
1659 if (tape->merge_bh)
1660 idetape_init_merge_buffer(tape);
1661 if (errors == IDETAPE_ERROR_GENERAL)
1662 return -EIO;
1663 return ret;
1664 }
1665
1666 static void idetape_create_inquiry_cmd(struct ide_atapi_pc *pc)
1667 {
1668 idetape_init_pc(pc);
1669 pc->c[0] = INQUIRY;
1670 pc->c[4] = 254;
1671 pc->req_xfer = 254;
1672 }
1673
1674 static void idetape_create_rewind_cmd(ide_drive_t *drive,
1675 struct ide_atapi_pc *pc)
1676 {
1677 idetape_init_pc(pc);
1678 pc->c[0] = REZERO_UNIT;
1679 pc->flags |= PC_FLAG_WAIT_FOR_DSC;
1680 }
1681
1682 static void idetape_create_erase_cmd(struct ide_atapi_pc *pc)
1683 {
1684 idetape_init_pc(pc);
1685 pc->c[0] = ERASE;
1686 pc->c[1] = 1;
1687 pc->flags |= PC_FLAG_WAIT_FOR_DSC;
1688 }
1689
1690 static void idetape_create_space_cmd(struct ide_atapi_pc *pc, int count, u8 cmd)
1691 {
1692 idetape_init_pc(pc);
1693 pc->c[0] = SPACE;
1694 put_unaligned(cpu_to_be32(count), (unsigned int *) &pc->c[1]);
1695 pc->c[1] = cmd;
1696 pc->flags |= PC_FLAG_WAIT_FOR_DSC;
1697 }
1698
1699 /* Queue up a character device originated write request. */
1700 static int idetape_add_chrdev_write_request(ide_drive_t *drive, int blocks)
1701 {
1702 idetape_tape_t *tape = drive->driver_data;
1703
1704 debug_log(DBG_CHRDEV, "Enter %s\n", __func__);
1705
1706 return idetape_queue_rw_tail(drive, REQ_IDETAPE_WRITE,
1707 blocks, tape->merge_bh);
1708 }
1709
1710 static void ide_tape_flush_merge_buffer(ide_drive_t *drive)
1711 {
1712 idetape_tape_t *tape = drive->driver_data;
1713 int blocks, min;
1714 struct idetape_bh *bh;
1715
1716 if (tape->chrdev_dir != IDETAPE_DIR_WRITE) {
1717 printk(KERN_ERR "ide-tape: bug: Trying to empty merge buffer"
1718 " but we are not writing.\n");
1719 return;
1720 }
1721 if (tape->merge_bh_size > tape->buffer_size) {
1722 printk(KERN_ERR "ide-tape: bug: merge_buffer too big\n");
1723 tape->merge_bh_size = tape->buffer_size;
1724 }
1725 if (tape->merge_bh_size) {
1726 blocks = tape->merge_bh_size / tape->blk_size;
1727 if (tape->merge_bh_size % tape->blk_size) {
1728 unsigned int i;
1729
1730 blocks++;
1731 i = tape->blk_size - tape->merge_bh_size %
1732 tape->blk_size;
1733 bh = tape->bh->b_reqnext;
1734 while (bh) {
1735 atomic_set(&bh->b_count, 0);
1736 bh = bh->b_reqnext;
1737 }
1738 bh = tape->bh;
1739 while (i) {
1740 if (bh == NULL) {
1741 printk(KERN_INFO "ide-tape: bug,"
1742 " bh NULL\n");
1743 break;
1744 }
1745 min = min(i, (unsigned int)(bh->b_size -
1746 atomic_read(&bh->b_count)));
1747 memset(bh->b_data + atomic_read(&bh->b_count),
1748 0, min);
1749 atomic_add(min, &bh->b_count);
1750 i -= min;
1751 bh = bh->b_reqnext;
1752 }
1753 }
1754 (void) idetape_add_chrdev_write_request(drive, blocks);
1755 tape->merge_bh_size = 0;
1756 }
1757 if (tape->merge_bh != NULL) {
1758 ide_tape_kfree_buffer(tape);
1759 tape->merge_bh = NULL;
1760 }
1761 tape->chrdev_dir = IDETAPE_DIR_NONE;
1762 }
1763
1764 static int idetape_init_read(ide_drive_t *drive)
1765 {
1766 idetape_tape_t *tape = drive->driver_data;
1767 int bytes_read;
1768
1769 /* Initialize read operation */
1770 if (tape->chrdev_dir != IDETAPE_DIR_READ) {
1771 if (tape->chrdev_dir == IDETAPE_DIR_WRITE) {
1772 ide_tape_flush_merge_buffer(drive);
1773 idetape_flush_tape_buffers(drive);
1774 }
1775 if (tape->merge_bh || tape->merge_bh_size) {
1776 printk(KERN_ERR "ide-tape: merge_bh_size should be"
1777 " 0 now\n");
1778 tape->merge_bh_size = 0;
1779 }
1780 tape->merge_bh = ide_tape_kmalloc_buffer(tape, 0, 0);
1781 if (!tape->merge_bh)
1782 return -ENOMEM;
1783 tape->chrdev_dir = IDETAPE_DIR_READ;
1784
1785 /*
1786 * Issue a read 0 command to ensure that DSC handshake is
1787 * switched from completion mode to buffer available mode.
1788 * No point in issuing this if DSC overlap isn't supported, some
1789 * drives (Seagate STT3401A) will return an error.
1790 */
1791 if (drive->dsc_overlap) {
1792 bytes_read = idetape_queue_rw_tail(drive,
1793 REQ_IDETAPE_READ, 0,
1794 tape->merge_bh);
1795 if (bytes_read < 0) {
1796 ide_tape_kfree_buffer(tape);
1797 tape->merge_bh = NULL;
1798 tape->chrdev_dir = IDETAPE_DIR_NONE;
1799 return bytes_read;
1800 }
1801 }
1802 }
1803
1804 return 0;
1805 }
1806
1807 /* called from idetape_chrdev_read() to service a chrdev read request. */
1808 static int idetape_add_chrdev_read_request(ide_drive_t *drive, int blocks)
1809 {
1810 idetape_tape_t *tape = drive->driver_data;
1811
1812 debug_log(DBG_PROCS, "Enter %s, %d blocks\n", __func__, blocks);
1813
1814 /* If we are at a filemark, return a read length of 0 */
1815 if (test_bit(IDETAPE_FLAG_FILEMARK, &tape->flags))
1816 return 0;
1817
1818 idetape_init_read(drive);
1819
1820 return idetape_queue_rw_tail(drive, REQ_IDETAPE_READ, blocks,
1821 tape->merge_bh);
1822 }
1823
1824 static void idetape_pad_zeros(ide_drive_t *drive, int bcount)
1825 {
1826 idetape_tape_t *tape = drive->driver_data;
1827 struct idetape_bh *bh;
1828 int blocks;
1829
1830 while (bcount) {
1831 unsigned int count;
1832
1833 bh = tape->merge_bh;
1834 count = min(tape->buffer_size, bcount);
1835 bcount -= count;
1836 blocks = count / tape->blk_size;
1837 while (count) {
1838 atomic_set(&bh->b_count,
1839 min(count, (unsigned int)bh->b_size));
1840 memset(bh->b_data, 0, atomic_read(&bh->b_count));
1841 count -= atomic_read(&bh->b_count);
1842 bh = bh->b_reqnext;
1843 }
1844 idetape_queue_rw_tail(drive, REQ_IDETAPE_WRITE, blocks,
1845 tape->merge_bh);
1846 }
1847 }
1848
1849 /*
1850 * Rewinds the tape to the Beginning Of the current Partition (BOP). We
1851 * currently support only one partition.
1852 */
1853 static int idetape_rewind_tape(ide_drive_t *drive)
1854 {
1855 int retval;
1856 struct ide_atapi_pc pc;
1857 idetape_tape_t *tape;
1858 tape = drive->driver_data;
1859
1860 debug_log(DBG_SENSE, "Enter %s\n", __func__);
1861
1862 idetape_create_rewind_cmd(drive, &pc);
1863 retval = idetape_queue_pc_tail(drive, &pc);
1864 if (retval)
1865 return retval;
1866
1867 idetape_create_read_position_cmd(&pc);
1868 retval = idetape_queue_pc_tail(drive, &pc);
1869 if (retval)
1870 return retval;
1871 return 0;
1872 }
1873
1874 /* mtio.h compatible commands should be issued to the chrdev interface. */
1875 static int idetape_blkdev_ioctl(ide_drive_t *drive, unsigned int cmd,
1876 unsigned long arg)
1877 {
1878 idetape_tape_t *tape = drive->driver_data;
1879 void __user *argp = (void __user *)arg;
1880
1881 struct idetape_config {
1882 int dsc_rw_frequency;
1883 int dsc_media_access_frequency;
1884 int nr_stages;
1885 } config;
1886
1887 debug_log(DBG_PROCS, "Enter %s\n", __func__);
1888
1889 switch (cmd) {
1890 case 0x0340:
1891 if (copy_from_user(&config, argp, sizeof(config)))
1892 return -EFAULT;
1893 tape->best_dsc_rw_freq = config.dsc_rw_frequency;
1894 break;
1895 case 0x0350:
1896 config.dsc_rw_frequency = (int) tape->best_dsc_rw_freq;
1897 config.nr_stages = 1;
1898 if (copy_to_user(argp, &config, sizeof(config)))
1899 return -EFAULT;
1900 break;
1901 default:
1902 return -EIO;
1903 }
1904 return 0;
1905 }
1906
1907 static int idetape_space_over_filemarks(ide_drive_t *drive, short mt_op,
1908 int mt_count)
1909 {
1910 idetape_tape_t *tape = drive->driver_data;
1911 struct ide_atapi_pc pc;
1912 int retval, count = 0;
1913 int sprev = !!(tape->caps[4] & 0x20);
1914
1915 if (mt_count == 0)
1916 return 0;
1917 if (MTBSF == mt_op || MTBSFM == mt_op) {
1918 if (!sprev)
1919 return -EIO;
1920 mt_count = -mt_count;
1921 }
1922
1923 if (tape->chrdev_dir == IDETAPE_DIR_READ) {
1924 tape->merge_bh_size = 0;
1925 if (test_and_clear_bit(IDETAPE_FLAG_FILEMARK, &tape->flags))
1926 ++count;
1927 ide_tape_discard_merge_buffer(drive, 0);
1928 }
1929
1930 switch (mt_op) {
1931 case MTFSF:
1932 case MTBSF:
1933 idetape_create_space_cmd(&pc, mt_count - count,
1934 IDETAPE_SPACE_OVER_FILEMARK);
1935 return idetape_queue_pc_tail(drive, &pc);
1936 case MTFSFM:
1937 case MTBSFM:
1938 if (!sprev)
1939 return -EIO;
1940 retval = idetape_space_over_filemarks(drive, MTFSF,
1941 mt_count - count);
1942 if (retval)
1943 return retval;
1944 count = (MTBSFM == mt_op ? 1 : -1);
1945 return idetape_space_over_filemarks(drive, MTFSF, count);
1946 default:
1947 printk(KERN_ERR "ide-tape: MTIO operation %d not supported\n",
1948 mt_op);
1949 return -EIO;
1950 }
1951 }
1952
1953 /*
1954 * Our character device read / write functions.
1955 *
1956 * The tape is optimized to maximize throughput when it is transferring an
1957 * integral number of the "continuous transfer limit", which is a parameter of
1958 * the specific tape (26kB on my particular tape, 32kB for Onstream).
1959 *
1960 * As of version 1.3 of the driver, the character device provides an abstract
1961 * continuous view of the media - any mix of block sizes (even 1 byte) on the
1962 * same backup/restore procedure is supported. The driver will internally
1963 * convert the requests to the recommended transfer unit, so that an unmatch
1964 * between the user's block size to the recommended size will only result in a
1965 * (slightly) increased driver overhead, but will no longer hit performance.
1966 * This is not applicable to Onstream.
1967 */
1968 static ssize_t idetape_chrdev_read(struct file *file, char __user *buf,
1969 size_t count, loff_t *ppos)
1970 {
1971 struct ide_tape_obj *tape = ide_tape_f(file);
1972 ide_drive_t *drive = tape->drive;
1973 ssize_t bytes_read, temp, actually_read = 0, rc;
1974 ssize_t ret = 0;
1975 u16 ctl = *(u16 *)&tape->caps[12];
1976
1977 debug_log(DBG_CHRDEV, "Enter %s, count %Zd\n", __func__, count);
1978
1979 if (tape->chrdev_dir != IDETAPE_DIR_READ) {
1980 if (test_bit(IDETAPE_FLAG_DETECT_BS, &tape->flags))
1981 if (count > tape->blk_size &&
1982 (count % tape->blk_size) == 0)
1983 tape->user_bs_factor = count / tape->blk_size;
1984 }
1985 rc = idetape_init_read(drive);
1986 if (rc < 0)
1987 return rc;
1988 if (count == 0)
1989 return (0);
1990 if (tape->merge_bh_size) {
1991 actually_read = min((unsigned int)(tape->merge_bh_size),
1992 (unsigned int)count);
1993 if (idetape_copy_stage_to_user(tape, buf, actually_read))
1994 ret = -EFAULT;
1995 buf += actually_read;
1996 tape->merge_bh_size -= actually_read;
1997 count -= actually_read;
1998 }
1999 while (count >= tape->buffer_size) {
2000 bytes_read = idetape_add_chrdev_read_request(drive, ctl);
2001 if (bytes_read <= 0)
2002 goto finish;
2003 if (idetape_copy_stage_to_user(tape, buf, bytes_read))
2004 ret = -EFAULT;
2005 buf += bytes_read;
2006 count -= bytes_read;
2007 actually_read += bytes_read;
2008 }
2009 if (count) {
2010 bytes_read = idetape_add_chrdev_read_request(drive, ctl);
2011 if (bytes_read <= 0)
2012 goto finish;
2013 temp = min((unsigned long)count, (unsigned long)bytes_read);
2014 if (idetape_copy_stage_to_user(tape, buf, temp))
2015 ret = -EFAULT;
2016 actually_read += temp;
2017 tape->merge_bh_size = bytes_read-temp;
2018 }
2019 finish:
2020 if (!actually_read && test_bit(IDETAPE_FLAG_FILEMARK, &tape->flags)) {
2021 debug_log(DBG_SENSE, "%s: spacing over filemark\n", tape->name);
2022
2023 idetape_space_over_filemarks(drive, MTFSF, 1);
2024 return 0;
2025 }
2026
2027 return ret ? ret : actually_read;
2028 }
2029
2030 static ssize_t idetape_chrdev_write(struct file *file, const char __user *buf,
2031 size_t count, loff_t *ppos)
2032 {
2033 struct ide_tape_obj *tape = ide_tape_f(file);
2034 ide_drive_t *drive = tape->drive;
2035 ssize_t actually_written = 0;
2036 ssize_t ret = 0;
2037 u16 ctl = *(u16 *)&tape->caps[12];
2038
2039 /* The drive is write protected. */
2040 if (tape->write_prot)
2041 return -EACCES;
2042
2043 debug_log(DBG_CHRDEV, "Enter %s, count %Zd\n", __func__, count);
2044
2045 /* Initialize write operation */
2046 if (tape->chrdev_dir != IDETAPE_DIR_WRITE) {
2047 if (tape->chrdev_dir == IDETAPE_DIR_READ)
2048 ide_tape_discard_merge_buffer(drive, 1);
2049 if (tape->merge_bh || tape->merge_bh_size) {
2050 printk(KERN_ERR "ide-tape: merge_bh_size "
2051 "should be 0 now\n");
2052 tape->merge_bh_size = 0;
2053 }
2054 tape->merge_bh = ide_tape_kmalloc_buffer(tape, 0, 0);
2055 if (!tape->merge_bh)
2056 return -ENOMEM;
2057 tape->chrdev_dir = IDETAPE_DIR_WRITE;
2058 idetape_init_merge_buffer(tape);
2059
2060 /*
2061 * Issue a write 0 command to ensure that DSC handshake is
2062 * switched from completion mode to buffer available mode. No
2063 * point in issuing this if DSC overlap isn't supported, some
2064 * drives (Seagate STT3401A) will return an error.
2065 */
2066 if (drive->dsc_overlap) {
2067 ssize_t retval = idetape_queue_rw_tail(drive,
2068 REQ_IDETAPE_WRITE, 0,
2069 tape->merge_bh);
2070 if (retval < 0) {
2071 ide_tape_kfree_buffer(tape);
2072 tape->merge_bh = NULL;
2073 tape->chrdev_dir = IDETAPE_DIR_NONE;
2074 return retval;
2075 }
2076 }
2077 }
2078 if (count == 0)
2079 return (0);
2080 if (tape->merge_bh_size) {
2081 if (tape->merge_bh_size >= tape->buffer_size) {
2082 printk(KERN_ERR "ide-tape: bug: merge buf too big\n");
2083 tape->merge_bh_size = 0;
2084 }
2085 actually_written = min((unsigned int)
2086 (tape->buffer_size - tape->merge_bh_size),
2087 (unsigned int)count);
2088 if (idetape_copy_stage_from_user(tape, buf, actually_written))
2089 ret = -EFAULT;
2090 buf += actually_written;
2091 tape->merge_bh_size += actually_written;
2092 count -= actually_written;
2093
2094 if (tape->merge_bh_size == tape->buffer_size) {
2095 ssize_t retval;
2096 tape->merge_bh_size = 0;
2097 retval = idetape_add_chrdev_write_request(drive, ctl);
2098 if (retval <= 0)
2099 return (retval);
2100 }
2101 }
2102 while (count >= tape->buffer_size) {
2103 ssize_t retval;
2104 if (idetape_copy_stage_from_user(tape, buf, tape->buffer_size))
2105 ret = -EFAULT;
2106 buf += tape->buffer_size;
2107 count -= tape->buffer_size;
2108 retval = idetape_add_chrdev_write_request(drive, ctl);
2109 actually_written += tape->buffer_size;
2110 if (retval <= 0)
2111 return (retval);
2112 }
2113 if (count) {
2114 actually_written += count;
2115 if (idetape_copy_stage_from_user(tape, buf, count))
2116 ret = -EFAULT;
2117 tape->merge_bh_size += count;
2118 }
2119 return ret ? ret : actually_written;
2120 }
2121
2122 static int idetape_write_filemark(ide_drive_t *drive)
2123 {
2124 struct ide_atapi_pc pc;
2125
2126 /* Write a filemark */
2127 idetape_create_write_filemark_cmd(drive, &pc, 1);
2128 if (idetape_queue_pc_tail(drive, &pc)) {
2129 printk(KERN_ERR "ide-tape: Couldn't write a filemark\n");
2130 return -EIO;
2131 }
2132 return 0;
2133 }
2134
2135 /*
2136 * Called from idetape_chrdev_ioctl when the general mtio MTIOCTOP ioctl is
2137 * requested.
2138 *
2139 * Note: MTBSF and MTBSFM are not supported when the tape doesn't support
2140 * spacing over filemarks in the reverse direction. In this case, MTFSFM is also
2141 * usually not supported.
2142 *
2143 * The following commands are currently not supported:
2144 *
2145 * MTFSS, MTBSS, MTWSM, MTSETDENSITY, MTSETDRVBUFFER, MT_ST_BOOLEANS,
2146 * MT_ST_WRITE_THRESHOLD.
2147 */
2148 static int idetape_mtioctop(ide_drive_t *drive, short mt_op, int mt_count)
2149 {
2150 idetape_tape_t *tape = drive->driver_data;
2151 struct ide_atapi_pc pc;
2152 int i, retval;
2153
2154 debug_log(DBG_ERR, "Handling MTIOCTOP ioctl: mt_op=%d, mt_count=%d\n",
2155 mt_op, mt_count);
2156
2157 switch (mt_op) {
2158 case MTFSF:
2159 case MTFSFM:
2160 case MTBSF:
2161 case MTBSFM:
2162 if (!mt_count)
2163 return 0;
2164 return idetape_space_over_filemarks(drive, mt_op, mt_count);
2165 default:
2166 break;
2167 }
2168
2169 switch (mt_op) {
2170 case MTWEOF:
2171 if (tape->write_prot)
2172 return -EACCES;
2173 ide_tape_discard_merge_buffer(drive, 1);
2174 for (i = 0; i < mt_count; i++) {
2175 retval = idetape_write_filemark(drive);
2176 if (retval)
2177 return retval;
2178 }
2179 return 0;
2180 case MTREW:
2181 ide_tape_discard_merge_buffer(drive, 0);
2182 if (idetape_rewind_tape(drive))
2183 return -EIO;
2184 return 0;
2185 case MTLOAD:
2186 ide_tape_discard_merge_buffer(drive, 0);
2187 idetape_create_load_unload_cmd(drive, &pc,
2188 IDETAPE_LU_LOAD_MASK);
2189 return idetape_queue_pc_tail(drive, &pc);
2190 case MTUNLOAD:
2191 case MTOFFL:
2192 /*
2193 * If door is locked, attempt to unlock before
2194 * attempting to eject.
2195 */
2196 if (tape->door_locked) {
2197 if (idetape_create_prevent_cmd(drive, &pc, 0))
2198 if (!idetape_queue_pc_tail(drive, &pc))
2199 tape->door_locked = DOOR_UNLOCKED;
2200 }
2201 ide_tape_discard_merge_buffer(drive, 0);
2202 idetape_create_load_unload_cmd(drive, &pc,
2203 !IDETAPE_LU_LOAD_MASK);
2204 retval = idetape_queue_pc_tail(drive, &pc);
2205 if (!retval)
2206 clear_bit(IDETAPE_FLAG_MEDIUM_PRESENT, &tape->flags);
2207 return retval;
2208 case MTNOP:
2209 ide_tape_discard_merge_buffer(drive, 0);
2210 return idetape_flush_tape_buffers(drive);
2211 case MTRETEN:
2212 ide_tape_discard_merge_buffer(drive, 0);
2213 idetape_create_load_unload_cmd(drive, &pc,
2214 IDETAPE_LU_RETENSION_MASK | IDETAPE_LU_LOAD_MASK);
2215 return idetape_queue_pc_tail(drive, &pc);
2216 case MTEOM:
2217 idetape_create_space_cmd(&pc, 0, IDETAPE_SPACE_TO_EOD);
2218 return idetape_queue_pc_tail(drive, &pc);
2219 case MTERASE:
2220 (void)idetape_rewind_tape(drive);
2221 idetape_create_erase_cmd(&pc);
2222 return idetape_queue_pc_tail(drive, &pc);
2223 case MTSETBLK:
2224 if (mt_count) {
2225 if (mt_count < tape->blk_size ||
2226 mt_count % tape->blk_size)
2227 return -EIO;
2228 tape->user_bs_factor = mt_count / tape->blk_size;
2229 clear_bit(IDETAPE_FLAG_DETECT_BS, &tape->flags);
2230 } else
2231 set_bit(IDETAPE_FLAG_DETECT_BS, &tape->flags);
2232 return 0;
2233 case MTSEEK:
2234 ide_tape_discard_merge_buffer(drive, 0);
2235 return idetape_position_tape(drive,
2236 mt_count * tape->user_bs_factor, tape->partition, 0);
2237 case MTSETPART:
2238 ide_tape_discard_merge_buffer(drive, 0);
2239 return idetape_position_tape(drive, 0, mt_count, 0);
2240 case MTFSR:
2241 case MTBSR:
2242 case MTLOCK:
2243 if (!idetape_create_prevent_cmd(drive, &pc, 1))
2244 return 0;
2245 retval = idetape_queue_pc_tail(drive, &pc);
2246 if (retval)
2247 return retval;
2248 tape->door_locked = DOOR_EXPLICITLY_LOCKED;
2249 return 0;
2250 case MTUNLOCK:
2251 if (!idetape_create_prevent_cmd(drive, &pc, 0))
2252 return 0;
2253 retval = idetape_queue_pc_tail(drive, &pc);
2254 if (retval)
2255 return retval;
2256 tape->door_locked = DOOR_UNLOCKED;
2257 return 0;
2258 default:
2259 printk(KERN_ERR "ide-tape: MTIO operation %d not supported\n",
2260 mt_op);
2261 return -EIO;
2262 }
2263 }
2264
2265 /*
2266 * Our character device ioctls. General mtio.h magnetic io commands are
2267 * supported here, and not in the corresponding block interface. Our own
2268 * ide-tape ioctls are supported on both interfaces.
2269 */
2270 static int idetape_chrdev_ioctl(struct inode *inode, struct file *file,
2271 unsigned int cmd, unsigned long arg)
2272 {
2273 struct ide_tape_obj *tape = ide_tape_f(file);
2274 ide_drive_t *drive = tape->drive;
2275 struct mtop mtop;
2276 struct mtget mtget;
2277 struct mtpos mtpos;
2278 int block_offset = 0, position = tape->first_frame;
2279 void __user *argp = (void __user *)arg;
2280
2281 debug_log(DBG_CHRDEV, "Enter %s, cmd=%u\n", __func__, cmd);
2282
2283 if (tape->chrdev_dir == IDETAPE_DIR_WRITE) {
2284 ide_tape_flush_merge_buffer(drive);
2285 idetape_flush_tape_buffers(drive);
2286 }
2287 if (cmd == MTIOCGET || cmd == MTIOCPOS) {
2288 block_offset = tape->merge_bh_size /
2289 (tape->blk_size * tape->user_bs_factor);
2290 position = idetape_read_position(drive);
2291 if (position < 0)
2292 return -EIO;
2293 }
2294 switch (cmd) {
2295 case MTIOCTOP:
2296 if (copy_from_user(&mtop, argp, sizeof(struct mtop)))
2297 return -EFAULT;
2298 return idetape_mtioctop(drive, mtop.mt_op, mtop.mt_count);
2299 case MTIOCGET:
2300 memset(&mtget, 0, sizeof(struct mtget));
2301 mtget.mt_type = MT_ISSCSI2;
2302 mtget.mt_blkno = position / tape->user_bs_factor - block_offset;
2303 mtget.mt_dsreg =
2304 ((tape->blk_size * tape->user_bs_factor)
2305 << MT_ST_BLKSIZE_SHIFT) & MT_ST_BLKSIZE_MASK;
2306
2307 if (tape->drv_write_prot)
2308 mtget.mt_gstat |= GMT_WR_PROT(0xffffffff);
2309
2310 if (copy_to_user(argp, &mtget, sizeof(struct mtget)))
2311 return -EFAULT;
2312 return 0;
2313 case MTIOCPOS:
2314 mtpos.mt_blkno = position / tape->user_bs_factor - block_offset;
2315 if (copy_to_user(argp, &mtpos, sizeof(struct mtpos)))
2316 return -EFAULT;
2317 return 0;
2318 default:
2319 if (tape->chrdev_dir == IDETAPE_DIR_READ)
2320 ide_tape_discard_merge_buffer(drive, 1);
2321 return idetape_blkdev_ioctl(drive, cmd, arg);
2322 }
2323 }
2324
2325 /*
2326 * Do a mode sense page 0 with block descriptor and if it succeeds set the tape
2327 * block size with the reported value.
2328 */
2329 static void ide_tape_get_bsize_from_bdesc(ide_drive_t *drive)
2330 {
2331 idetape_tape_t *tape = drive->driver_data;
2332 struct ide_atapi_pc pc;
2333
2334 idetape_create_mode_sense_cmd(&pc, IDETAPE_BLOCK_DESCRIPTOR);
2335 if (idetape_queue_pc_tail(drive, &pc)) {
2336 printk(KERN_ERR "ide-tape: Can't get block descriptor\n");
2337 if (tape->blk_size == 0) {
2338 printk(KERN_WARNING "ide-tape: Cannot deal with zero "
2339 "block size, assuming 32k\n");
2340 tape->blk_size = 32768;
2341 }
2342 return;
2343 }
2344 tape->blk_size = (pc.buf[4 + 5] << 16) +
2345 (pc.buf[4 + 6] << 8) +
2346 pc.buf[4 + 7];
2347 tape->drv_write_prot = (pc.buf[2] & 0x80) >> 7;
2348 }
2349
2350 static int idetape_chrdev_open(struct inode *inode, struct file *filp)
2351 {
2352 unsigned int minor = iminor(inode), i = minor & ~0xc0;
2353 ide_drive_t *drive;
2354 idetape_tape_t *tape;
2355 struct ide_atapi_pc pc;
2356 int retval;
2357
2358 if (i >= MAX_HWIFS * MAX_DRIVES)
2359 return -ENXIO;
2360
2361 tape = ide_tape_chrdev_get(i);
2362 if (!tape)
2363 return -ENXIO;
2364
2365 debug_log(DBG_CHRDEV, "Enter %s\n", __func__);
2366
2367 /*
2368 * We really want to do nonseekable_open(inode, filp); here, but some
2369 * versions of tar incorrectly call lseek on tapes and bail out if that
2370 * fails. So we disallow pread() and pwrite(), but permit lseeks.
2371 */
2372 filp->f_mode &= ~(FMODE_PREAD | FMODE_PWRITE);
2373
2374 drive = tape->drive;
2375
2376 filp->private_data = tape;
2377
2378 if (test_and_set_bit(IDETAPE_FLAG_BUSY, &tape->flags)) {
2379 retval = -EBUSY;
2380 goto out_put_tape;
2381 }
2382
2383 retval = idetape_wait_ready(drive, 60 * HZ);
2384 if (retval) {
2385 clear_bit(IDETAPE_FLAG_BUSY, &tape->flags);
2386 printk(KERN_ERR "ide-tape: %s: drive not ready\n", tape->name);
2387 goto out_put_tape;
2388 }
2389
2390 idetape_read_position(drive);
2391 if (!test_bit(IDETAPE_FLAG_ADDRESS_VALID, &tape->flags))
2392 (void)idetape_rewind_tape(drive);
2393
2394 /* Read block size and write protect status from drive. */
2395 ide_tape_get_bsize_from_bdesc(drive);
2396
2397 /* Set write protect flag if device is opened as read-only. */
2398 if ((filp->f_flags & O_ACCMODE) == O_RDONLY)
2399 tape->write_prot = 1;
2400 else
2401 tape->write_prot = tape->drv_write_prot;
2402
2403 /* Make sure drive isn't write protected if user wants to write. */
2404 if (tape->write_prot) {
2405 if ((filp->f_flags & O_ACCMODE) == O_WRONLY ||
2406 (filp->f_flags & O_ACCMODE) == O_RDWR) {
2407 clear_bit(IDETAPE_FLAG_BUSY, &tape->flags);
2408 retval = -EROFS;
2409 goto out_put_tape;
2410 }
2411 }
2412
2413 /* Lock the tape drive door so user can't eject. */
2414 if (tape->chrdev_dir == IDETAPE_DIR_NONE) {
2415 if (idetape_create_prevent_cmd(drive, &pc, 1)) {
2416 if (!idetape_queue_pc_tail(drive, &pc)) {
2417 if (tape->door_locked != DOOR_EXPLICITLY_LOCKED)
2418 tape->door_locked = DOOR_LOCKED;
2419 }
2420 }
2421 }
2422 return 0;
2423
2424 out_put_tape:
2425 ide_tape_put(tape);
2426 return retval;
2427 }
2428
2429 static void idetape_write_release(ide_drive_t *drive, unsigned int minor)
2430 {
2431 idetape_tape_t *tape = drive->driver_data;
2432
2433 ide_tape_flush_merge_buffer(drive);
2434 tape->merge_bh = ide_tape_kmalloc_buffer(tape, 1, 0);
2435 if (tape->merge_bh != NULL) {
2436 idetape_pad_zeros(drive, tape->blk_size *
2437 (tape->user_bs_factor - 1));
2438 ide_tape_kfree_buffer(tape);
2439 tape->merge_bh = NULL;
2440 }
2441 idetape_write_filemark(drive);
2442 idetape_flush_tape_buffers(drive);
2443 idetape_flush_tape_buffers(drive);
2444 }
2445
2446 static int idetape_chrdev_release(struct inode *inode, struct file *filp)
2447 {
2448 struct ide_tape_obj *tape = ide_tape_f(filp);
2449 ide_drive_t *drive = tape->drive;
2450 struct ide_atapi_pc pc;
2451 unsigned int minor = iminor(inode);
2452
2453 lock_kernel();
2454 tape = drive->driver_data;
2455
2456 debug_log(DBG_CHRDEV, "Enter %s\n", __func__);
2457
2458 if (tape->chrdev_dir == IDETAPE_DIR_WRITE)
2459 idetape_write_release(drive, minor);
2460 if (tape->chrdev_dir == IDETAPE_DIR_READ) {
2461 if (minor < 128)
2462 ide_tape_discard_merge_buffer(drive, 1);
2463 }
2464
2465 if (minor < 128 && test_bit(IDETAPE_FLAG_MEDIUM_PRESENT, &tape->flags))
2466 (void) idetape_rewind_tape(drive);
2467 if (tape->chrdev_dir == IDETAPE_DIR_NONE) {
2468 if (tape->door_locked == DOOR_LOCKED) {
2469 if (idetape_create_prevent_cmd(drive, &pc, 0)) {
2470 if (!idetape_queue_pc_tail(drive, &pc))
2471 tape->door_locked = DOOR_UNLOCKED;
2472 }
2473 }
2474 }
2475 clear_bit(IDETAPE_FLAG_BUSY, &tape->flags);
2476 ide_tape_put(tape);
2477 unlock_kernel();
2478 return 0;
2479 }
2480
2481 /*
2482 * check the contents of the ATAPI IDENTIFY command results. We return:
2483 *
2484 * 1 - If the tape can be supported by us, based on the information we have so
2485 * far.
2486 *
2487 * 0 - If this tape driver is not currently supported by us.
2488 */
2489 static int idetape_identify_device(ide_drive_t *drive)
2490 {
2491 u8 gcw[2], protocol, device_type, removable, packet_size;
2492
2493 if (drive->id_read == 0)
2494 return 1;
2495
2496 *((unsigned short *) &gcw) = drive->id->config;
2497
2498 protocol = (gcw[1] & 0xC0) >> 6;
2499 device_type = gcw[1] & 0x1F;
2500 removable = !!(gcw[0] & 0x80);
2501 packet_size = gcw[0] & 0x3;
2502
2503 /* Check that we can support this device */
2504 if (protocol != 2)
2505 printk(KERN_ERR "ide-tape: Protocol (0x%02x) is not ATAPI\n",
2506 protocol);
2507 else if (device_type != 1)
2508 printk(KERN_ERR "ide-tape: Device type (0x%02x) is not set "
2509 "to tape\n", device_type);
2510 else if (!removable)
2511 printk(KERN_ERR "ide-tape: The removable flag is not set\n");
2512 else if (packet_size != 0) {
2513 printk(KERN_ERR "ide-tape: Packet size (0x%02x) is not 12"
2514 " bytes\n", packet_size);
2515 } else
2516 return 1;
2517 return 0;
2518 }
2519
2520 static void idetape_get_inquiry_results(ide_drive_t *drive)
2521 {
2522 idetape_tape_t *tape = drive->driver_data;
2523 struct ide_atapi_pc pc;
2524 char fw_rev[6], vendor_id[10], product_id[18];
2525
2526 idetape_create_inquiry_cmd(&pc);
2527 if (idetape_queue_pc_tail(drive, &pc)) {
2528 printk(KERN_ERR "ide-tape: %s: can't get INQUIRY results\n",
2529 tape->name);
2530 return;
2531 }
2532 memcpy(vendor_id, &pc.buf[8], 8);
2533 memcpy(product_id, &pc.buf[16], 16);
2534 memcpy(fw_rev, &pc.buf[32], 4);
2535
2536 ide_fixstring(vendor_id, 10, 0);
2537 ide_fixstring(product_id, 18, 0);
2538 ide_fixstring(fw_rev, 6, 0);
2539
2540 printk(KERN_INFO "ide-tape: %s <-> %s: %s %s rev %s\n",
2541 drive->name, tape->name, vendor_id, product_id, fw_rev);
2542 }
2543
2544 /*
2545 * Ask the tape about its various parameters. In particular, we will adjust our
2546 * data transfer buffer size to the recommended value as returned by the tape.
2547 */
2548 static void idetape_get_mode_sense_results(ide_drive_t *drive)
2549 {
2550 idetape_tape_t *tape = drive->driver_data;
2551 struct ide_atapi_pc pc;
2552 u8 *caps;
2553 u8 speed, max_speed;
2554
2555 idetape_create_mode_sense_cmd(&pc, IDETAPE_CAPABILITIES_PAGE);
2556 if (idetape_queue_pc_tail(drive, &pc)) {
2557 printk(KERN_ERR "ide-tape: Can't get tape parameters - assuming"
2558 " some default values\n");
2559 tape->blk_size = 512;
2560 put_unaligned(52, (u16 *)&tape->caps[12]);
2561 put_unaligned(540, (u16 *)&tape->caps[14]);
2562 put_unaligned(6*52, (u16 *)&tape->caps[16]);
2563 return;
2564 }
2565 caps = pc.buf + 4 + pc.buf[3];
2566
2567 /* convert to host order and save for later use */
2568 speed = be16_to_cpu(*(u16 *)&caps[14]);
2569 max_speed = be16_to_cpu(*(u16 *)&caps[8]);
2570
2571 put_unaligned(max_speed, (u16 *)&caps[8]);
2572 put_unaligned(be16_to_cpu(*(u16 *)&caps[12]), (u16 *)&caps[12]);
2573 put_unaligned(speed, (u16 *)&caps[14]);
2574 put_unaligned(be16_to_cpu(*(u16 *)&caps[16]), (u16 *)&caps[16]);
2575
2576 if (!speed) {
2577 printk(KERN_INFO "ide-tape: %s: invalid tape speed "
2578 "(assuming 650KB/sec)\n", drive->name);
2579 put_unaligned(650, (u16 *)&caps[14]);
2580 }
2581 if (!max_speed) {
2582 printk(KERN_INFO "ide-tape: %s: invalid max_speed "
2583 "(assuming 650KB/sec)\n", drive->name);
2584 put_unaligned(650, (u16 *)&caps[8]);
2585 }
2586
2587 memcpy(&tape->caps, caps, 20);
2588 if (caps[7] & 0x02)
2589 tape->blk_size = 512;
2590 else if (caps[7] & 0x04)
2591 tape->blk_size = 1024;
2592 }
2593
2594 #ifdef CONFIG_IDE_PROC_FS
2595 static void idetape_add_settings(ide_drive_t *drive)
2596 {
2597 idetape_tape_t *tape = drive->driver_data;
2598
2599 ide_add_setting(drive, "buffer", SETTING_READ, TYPE_SHORT, 0, 0xffff,
2600 1, 2, (u16 *)&tape->caps[16], NULL);
2601 ide_add_setting(drive, "speed", SETTING_READ, TYPE_SHORT, 0, 0xffff,
2602 1, 1, (u16 *)&tape->caps[14], NULL);
2603 ide_add_setting(drive, "buffer_size", SETTING_READ, TYPE_INT, 0, 0xffff,
2604 1, 1024, &tape->buffer_size, NULL);
2605 ide_add_setting(drive, "tdsc", SETTING_RW, TYPE_INT, IDETAPE_DSC_RW_MIN,
2606 IDETAPE_DSC_RW_MAX, 1000, HZ, &tape->best_dsc_rw_freq,
2607 NULL);
2608 ide_add_setting(drive, "dsc_overlap", SETTING_RW, TYPE_BYTE, 0, 1, 1,
2609 1, &drive->dsc_overlap, NULL);
2610 ide_add_setting(drive, "avg_speed", SETTING_READ, TYPE_INT, 0, 0xffff,
2611 1, 1, &tape->avg_speed, NULL);
2612 ide_add_setting(drive, "debug_mask", SETTING_RW, TYPE_INT, 0, 0xffff, 1,
2613 1, &tape->debug_mask, NULL);
2614 }
2615 #else
2616 static inline void idetape_add_settings(ide_drive_t *drive) { ; }
2617 #endif
2618
2619 /*
2620 * The function below is called to:
2621 *
2622 * 1. Initialize our various state variables.
2623 * 2. Ask the tape for its capabilities.
2624 * 3. Allocate a buffer which will be used for data transfer. The buffer size
2625 * is chosen based on the recommendation which we received in step 2.
2626 *
2627 * Note that at this point ide.c already assigned us an irq, so that we can
2628 * queue requests here and wait for their completion.
2629 */
2630 static void idetape_setup(ide_drive_t *drive, idetape_tape_t *tape, int minor)
2631 {
2632 unsigned long t;
2633 int speed;
2634 int buffer_size;
2635 u8 gcw[2];
2636 u16 *ctl = (u16 *)&tape->caps[12];
2637
2638 spin_lock_init(&tape->lock);
2639 drive->dsc_overlap = 1;
2640 if (drive->hwif->host_flags & IDE_HFLAG_NO_DSC) {
2641 printk(KERN_INFO "ide-tape: %s: disabling DSC overlap\n",
2642 tape->name);
2643 drive->dsc_overlap = 0;
2644 }
2645 /* Seagate Travan drives do not support DSC overlap. */
2646 if (strstr(drive->id->model, "Seagate STT3401"))
2647 drive->dsc_overlap = 0;
2648 tape->minor = minor;
2649 tape->name[0] = 'h';
2650 tape->name[1] = 't';
2651 tape->name[2] = '0' + minor;
2652 tape->chrdev_dir = IDETAPE_DIR_NONE;
2653 tape->pc = tape->pc_stack;
2654 *((unsigned short *) &gcw) = drive->id->config;
2655
2656 /* Command packet DRQ type */
2657 if (((gcw[0] & 0x60) >> 5) == 1)
2658 set_bit(IDETAPE_FLAG_DRQ_INTERRUPT, &tape->flags);
2659
2660 idetape_get_inquiry_results(drive);
2661 idetape_get_mode_sense_results(drive);
2662 ide_tape_get_bsize_from_bdesc(drive);
2663 tape->user_bs_factor = 1;
2664 tape->buffer_size = *ctl * tape->blk_size;
2665 while (tape->buffer_size > 0xffff) {
2666 printk(KERN_NOTICE "ide-tape: decreasing stage size\n");
2667 *ctl /= 2;
2668 tape->buffer_size = *ctl * tape->blk_size;
2669 }
2670 buffer_size = tape->buffer_size;
2671 tape->pages_per_buffer = buffer_size / PAGE_SIZE;
2672 if (buffer_size % PAGE_SIZE) {
2673 tape->pages_per_buffer++;
2674 tape->excess_bh_size = PAGE_SIZE - buffer_size % PAGE_SIZE;
2675 }
2676
2677 /* select the "best" DSC read/write polling freq */
2678 speed = max(*(u16 *)&tape->caps[14], *(u16 *)&tape->caps[8]);
2679
2680 t = (IDETAPE_FIFO_THRESHOLD * tape->buffer_size * HZ) / (speed * 1000);
2681
2682 /*
2683 * Ensure that the number we got makes sense; limit it within
2684 * IDETAPE_DSC_RW_MIN and IDETAPE_DSC_RW_MAX.
2685 */
2686 tape->best_dsc_rw_freq = clamp_t(unsigned long, t, IDETAPE_DSC_RW_MIN,
2687 IDETAPE_DSC_RW_MAX);
2688 printk(KERN_INFO "ide-tape: %s <-> %s: %dKBps, %d*%dkB buffer, "
2689 "%lums tDSC%s\n",
2690 drive->name, tape->name, *(u16 *)&tape->caps[14],
2691 (*(u16 *)&tape->caps[16] * 512) / tape->buffer_size,
2692 tape->buffer_size / 1024,
2693 tape->best_dsc_rw_freq * 1000 / HZ,
2694 drive->using_dma ? ", DMA":"");
2695
2696 idetape_add_settings(drive);
2697 }
2698
2699 static void ide_tape_remove(ide_drive_t *drive)
2700 {
2701 idetape_tape_t *tape = drive->driver_data;
2702
2703 ide_proc_unregister_driver(drive, tape->driver);
2704
2705 ide_unregister_region(tape->disk);
2706
2707 ide_tape_put(tape);
2708 }
2709
2710 static void ide_tape_release(struct kref *kref)
2711 {
2712 struct ide_tape_obj *tape = to_ide_tape(kref);
2713 ide_drive_t *drive = tape->drive;
2714 struct gendisk *g = tape->disk;
2715
2716 BUG_ON(tape->merge_bh_size);
2717
2718 drive->dsc_overlap = 0;
2719 drive->driver_data = NULL;
2720 device_destroy(idetape_sysfs_class, MKDEV(IDETAPE_MAJOR, tape->minor));
2721 device_destroy(idetape_sysfs_class,
2722 MKDEV(IDETAPE_MAJOR, tape->minor + 128));
2723 idetape_devs[tape->minor] = NULL;
2724 g->private_data = NULL;
2725 put_disk(g);
2726 kfree(tape);
2727 }
2728
2729 #ifdef CONFIG_IDE_PROC_FS
2730 static int proc_idetape_read_name
2731 (char *page, char **start, off_t off, int count, int *eof, void *data)
2732 {
2733 ide_drive_t *drive = (ide_drive_t *) data;
2734 idetape_tape_t *tape = drive->driver_data;
2735 char *out = page;
2736 int len;
2737
2738 len = sprintf(out, "%s\n", tape->name);
2739 PROC_IDE_READ_RETURN(page, start, off, count, eof, len);
2740 }
2741
2742 static ide_proc_entry_t idetape_proc[] = {
2743 { "capacity", S_IFREG|S_IRUGO, proc_ide_read_capacity, NULL },
2744 { "name", S_IFREG|S_IRUGO, proc_idetape_read_name, NULL },
2745 { NULL, 0, NULL, NULL }
2746 };
2747 #endif
2748
2749 static int ide_tape_probe(ide_drive_t *);
2750
2751 static ide_driver_t idetape_driver = {
2752 .gen_driver = {
2753 .owner = THIS_MODULE,
2754 .name = "ide-tape",
2755 .bus = &ide_bus_type,
2756 },
2757 .probe = ide_tape_probe,
2758 .remove = ide_tape_remove,
2759 .version = IDETAPE_VERSION,
2760 .media = ide_tape,
2761 .supports_dsc_overlap = 1,
2762 .do_request = idetape_do_request,
2763 .end_request = idetape_end_request,
2764 .error = __ide_error,
2765 .abort = __ide_abort,
2766 #ifdef CONFIG_IDE_PROC_FS
2767 .proc = idetape_proc,
2768 #endif
2769 };
2770
2771 /* Our character device supporting functions, passed to register_chrdev. */
2772 static const struct file_operations idetape_fops = {
2773 .owner = THIS_MODULE,
2774 .read = idetape_chrdev_read,
2775 .write = idetape_chrdev_write,
2776 .ioctl = idetape_chrdev_ioctl,
2777 .open = idetape_chrdev_open,
2778 .release = idetape_chrdev_release,
2779 };
2780
2781 static int idetape_open(struct inode *inode, struct file *filp)
2782 {
2783 struct gendisk *disk = inode->i_bdev->bd_disk;
2784 struct ide_tape_obj *tape;
2785
2786 tape = ide_tape_get(disk);
2787 if (!tape)
2788 return -ENXIO;
2789
2790 return 0;
2791 }
2792
2793 static int idetape_release(struct inode *inode, struct file *filp)
2794 {
2795 struct gendisk *disk = inode->i_bdev->bd_disk;
2796 struct ide_tape_obj *tape = ide_tape_g(disk);
2797
2798 ide_tape_put(tape);
2799
2800 return 0;
2801 }
2802
2803 static int idetape_ioctl(struct inode *inode, struct file *file,
2804 unsigned int cmd, unsigned long arg)
2805 {
2806 struct block_device *bdev = inode->i_bdev;
2807 struct ide_tape_obj *tape = ide_tape_g(bdev->bd_disk);
2808 ide_drive_t *drive = tape->drive;
2809 int err = generic_ide_ioctl(drive, file, bdev, cmd, arg);
2810 if (err == -EINVAL)
2811 err = idetape_blkdev_ioctl(drive, cmd, arg);
2812 return err;
2813 }
2814
2815 static struct block_device_operations idetape_block_ops = {
2816 .owner = THIS_MODULE,
2817 .open = idetape_open,
2818 .release = idetape_release,
2819 .ioctl = idetape_ioctl,
2820 };
2821
2822 static int ide_tape_probe(ide_drive_t *drive)
2823 {
2824 idetape_tape_t *tape;
2825 struct gendisk *g;
2826 int minor;
2827
2828 if (!strstr("ide-tape", drive->driver_req))
2829 goto failed;
2830 if (!drive->present)
2831 goto failed;
2832 if (drive->media != ide_tape)
2833 goto failed;
2834 if (!idetape_identify_device(drive)) {
2835 printk(KERN_ERR "ide-tape: %s: not supported by this version of"
2836 " the driver\n", drive->name);
2837 goto failed;
2838 }
2839 if (drive->scsi) {
2840 printk(KERN_INFO "ide-tape: passing drive %s to ide-scsi"
2841 " emulation.\n", drive->name);
2842 goto failed;
2843 }
2844 tape = kzalloc(sizeof(idetape_tape_t), GFP_KERNEL);
2845 if (tape == NULL) {
2846 printk(KERN_ERR "ide-tape: %s: Can't allocate a tape struct\n",
2847 drive->name);
2848 goto failed;
2849 }
2850
2851 g = alloc_disk(1 << PARTN_BITS);
2852 if (!g)
2853 goto out_free_tape;
2854
2855 ide_init_disk(g, drive);
2856
2857 ide_proc_register_driver(drive, &idetape_driver);
2858
2859 kref_init(&tape->kref);
2860
2861 tape->drive = drive;
2862 tape->driver = &idetape_driver;
2863 tape->disk = g;
2864
2865 g->private_data = &tape->driver;
2866
2867 drive->driver_data = tape;
2868
2869 mutex_lock(&idetape_ref_mutex);
2870 for (minor = 0; idetape_devs[minor]; minor++)
2871 ;
2872 idetape_devs[minor] = tape;
2873 mutex_unlock(&idetape_ref_mutex);
2874
2875 idetape_setup(drive, tape, minor);
2876
2877 device_create(idetape_sysfs_class, &drive->gendev,
2878 MKDEV(IDETAPE_MAJOR, minor), "%s", tape->name);
2879 device_create(idetape_sysfs_class, &drive->gendev,
2880 MKDEV(IDETAPE_MAJOR, minor + 128), "n%s", tape->name);
2881
2882 g->fops = &idetape_block_ops;
2883 ide_register_region(g);
2884
2885 return 0;
2886
2887 out_free_tape:
2888 kfree(tape);
2889 failed:
2890 return -ENODEV;
2891 }
2892
2893 static void __exit idetape_exit(void)
2894 {
2895 driver_unregister(&idetape_driver.gen_driver);
2896 class_destroy(idetape_sysfs_class);
2897 unregister_chrdev(IDETAPE_MAJOR, "ht");
2898 }
2899
2900 static int __init idetape_init(void)
2901 {
2902 int error = 1;
2903 idetape_sysfs_class = class_create(THIS_MODULE, "ide_tape");
2904 if (IS_ERR(idetape_sysfs_class)) {
2905 idetape_sysfs_class = NULL;
2906 printk(KERN_ERR "Unable to create sysfs class for ide tapes\n");
2907 error = -EBUSY;
2908 goto out;
2909 }
2910
2911 if (register_chrdev(IDETAPE_MAJOR, "ht", &idetape_fops)) {
2912 printk(KERN_ERR "ide-tape: Failed to register chrdev"
2913 " interface\n");
2914 error = -EBUSY;
2915 goto out_free_class;
2916 }
2917
2918 error = driver_register(&idetape_driver.gen_driver);
2919 if (error)
2920 goto out_free_driver;
2921
2922 return 0;
2923
2924 out_free_driver:
2925 driver_unregister(&idetape_driver.gen_driver);
2926 out_free_class:
2927 class_destroy(idetape_sysfs_class);
2928 out:
2929 return error;
2930 }
2931
2932 MODULE_ALIAS("ide:*m-tape*");
2933 module_init(idetape_init);
2934 module_exit(idetape_exit);
2935 MODULE_ALIAS_CHARDEV_MAJOR(IDETAPE_MAJOR);
2936 MODULE_DESCRIPTION("ATAPI Streaming TAPE Driver");
2937 MODULE_LICENSE("GPL");
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