ide-tape: fix handling of postponed rqs
[linux-2.6.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 DRV_NAME "ide-tape"
19
20 #define IDETAPE_VERSION "1.20"
21
22 #include <linux/module.h>
23 #include <linux/types.h>
24 #include <linux/string.h>
25 #include <linux/kernel.h>
26 #include <linux/delay.h>
27 #include <linux/timer.h>
28 #include <linux/mm.h>
29 #include <linux/interrupt.h>
30 #include <linux/jiffies.h>
31 #include <linux/major.h>
32 #include <linux/errno.h>
33 #include <linux/genhd.h>
34 #include <linux/slab.h>
35 #include <linux/pci.h>
36 #include <linux/ide.h>
37 #include <linux/smp_lock.h>
38 #include <linux/completion.h>
39 #include <linux/bitops.h>
40 #include <linux/mutex.h>
41 #include <scsi/scsi.h>
42
43 #include <asm/byteorder.h>
44 #include <linux/irq.h>
45 #include <linux/uaccess.h>
46 #include <linux/io.h>
47 #include <asm/unaligned.h>
48 #include <linux/mtio.h>
49
50 /* define to see debug info */
51 #undef IDETAPE_DEBUG_LOG
52
53 #ifdef IDETAPE_DEBUG_LOG
54 #define ide_debug_log(lvl, fmt, args...) __ide_debug_log(lvl, fmt, ## args)
55 #else
56 #define ide_debug_log(lvl, fmt, args...) do {} while (0)
57 #endif
58
59 /**************************** Tunable parameters *****************************/
60 /*
61  * After each failed packet command we issue a request sense command and retry
62  * the packet command IDETAPE_MAX_PC_RETRIES times.
63  *
64  * Setting IDETAPE_MAX_PC_RETRIES to 0 will disable retries.
65  */
66 #define IDETAPE_MAX_PC_RETRIES          3
67
68 /*
69  * The following parameter is used to select the point in the internal tape fifo
70  * in which we will start to refill the buffer. Decreasing the following
71  * parameter will improve the system's latency and interactive response, while
72  * using a high value might improve system throughput.
73  */
74 #define IDETAPE_FIFO_THRESHOLD          2
75
76 /*
77  * DSC polling parameters.
78  *
79  * Polling for DSC (a single bit in the status register) is a very important
80  * function in ide-tape. There are two cases in which we poll for DSC:
81  *
82  * 1. Before a read/write packet command, to ensure that we can transfer data
83  * from/to the tape's data buffers, without causing an actual media access.
84  * In case the tape is not ready yet, we take out our request from the device
85  * request queue, so that ide.c could service requests from the other device
86  * on the same interface in the meantime.
87  *
88  * 2. After the successful initialization of a "media access packet command",
89  * which is a command that can take a long time to complete (the interval can
90  * range from several seconds to even an hour). Again, we postpone our request
91  * in the middle to free the bus for the other device. The polling frequency
92  * here should be lower than the read/write frequency since those media access
93  * commands are slow. We start from a "fast" frequency - IDETAPE_DSC_MA_FAST
94  * (1 second), and if we don't receive DSC after IDETAPE_DSC_MA_THRESHOLD
95  * (5 min), we switch it to a lower frequency - IDETAPE_DSC_MA_SLOW (1 min).
96  *
97  * We also set a timeout for the timer, in case something goes wrong. The
98  * timeout should be longer then the maximum execution time of a tape operation.
99  */
100
101 /* DSC timings. */
102 #define IDETAPE_DSC_RW_MIN              5*HZ/100        /* 50 msec */
103 #define IDETAPE_DSC_RW_MAX              40*HZ/100       /* 400 msec */
104 #define IDETAPE_DSC_RW_TIMEOUT          2*60*HZ         /* 2 minutes */
105 #define IDETAPE_DSC_MA_FAST             2*HZ            /* 2 seconds */
106 #define IDETAPE_DSC_MA_THRESHOLD        5*60*HZ         /* 5 minutes */
107 #define IDETAPE_DSC_MA_SLOW             30*HZ           /* 30 seconds */
108 #define IDETAPE_DSC_MA_TIMEOUT          2*60*60*HZ      /* 2 hours */
109
110 /*************************** End of tunable parameters ***********************/
111
112 /* tape directions */
113 enum {
114         IDETAPE_DIR_NONE  = (1 << 0),
115         IDETAPE_DIR_READ  = (1 << 1),
116         IDETAPE_DIR_WRITE = (1 << 2),
117 };
118
119 /* Tape door status */
120 #define DOOR_UNLOCKED                   0
121 #define DOOR_LOCKED                     1
122 #define DOOR_EXPLICITLY_LOCKED          2
123
124 /* Some defines for the SPACE command */
125 #define IDETAPE_SPACE_OVER_FILEMARK     1
126 #define IDETAPE_SPACE_TO_EOD            3
127
128 /* Some defines for the LOAD UNLOAD command */
129 #define IDETAPE_LU_LOAD_MASK            1
130 #define IDETAPE_LU_RETENSION_MASK       2
131 #define IDETAPE_LU_EOT_MASK             4
132
133 /* Structures related to the SELECT SENSE / MODE SENSE packet commands. */
134 #define IDETAPE_BLOCK_DESCRIPTOR        0
135 #define IDETAPE_CAPABILITIES_PAGE       0x2a
136
137 /*
138  * Most of our global data which we need to save even as we leave the driver due
139  * to an interrupt or a timer event is stored in the struct defined below.
140  */
141 typedef struct ide_tape_obj {
142         ide_drive_t             *drive;
143         struct ide_driver       *driver;
144         struct gendisk          *disk;
145         struct device           dev;
146
147         /* used by REQ_IDETAPE_{READ,WRITE} requests */
148         struct ide_atapi_pc queued_pc;
149
150         /*
151          * DSC polling variables.
152          *
153          * While polling for DSC we use postponed_rq to postpone the current
154          * request so that ide.c will be able to service pending requests on the
155          * other device. Note that at most we will have only one DSC (usually
156          * data transfer) request in the device request queue.
157          */
158         bool postponed_rq;
159
160         /* The time in which we started polling for DSC */
161         unsigned long dsc_polling_start;
162         /* Timer used to poll for dsc */
163         struct timer_list dsc_timer;
164         /* Read/Write dsc polling frequency */
165         unsigned long best_dsc_rw_freq;
166         unsigned long dsc_poll_freq;
167         unsigned long dsc_timeout;
168
169         /* Read position information */
170         u8 partition;
171         /* Current block */
172         unsigned int first_frame;
173
174         /* Last error information */
175         u8 sense_key, asc, ascq;
176
177         /* Character device operation */
178         unsigned int minor;
179         /* device name */
180         char name[4];
181         /* Current character device data transfer direction */
182         u8 chrdev_dir;
183
184         /* tape block size, usually 512 or 1024 bytes */
185         unsigned short blk_size;
186         int user_bs_factor;
187
188         /* Copy of the tape's Capabilities and Mechanical Page */
189         u8 caps[20];
190
191         /*
192          * Active data transfer request parameters.
193          *
194          * At most, there is only one ide-tape originated data transfer request
195          * in the device request queue. This allows ide.c to easily service
196          * requests from the other device when we postpone our active request.
197          */
198
199         /* Data buffer size chosen based on the tape's recommendation */
200         int buffer_size;
201         /* Staging buffer of buffer_size bytes */
202         void *buf;
203         /* The read/write cursor */
204         void *cur;
205         /* The number of valid bytes in buf */
206         size_t valid;
207
208         /* Measures average tape speed */
209         unsigned long avg_time;
210         int avg_size;
211         int avg_speed;
212
213         /* the door is currently locked */
214         int door_locked;
215         /* the tape hardware is write protected */
216         char drv_write_prot;
217         /* the tape is write protected (hardware or opened as read-only) */
218         char write_prot;
219 } idetape_tape_t;
220
221 static DEFINE_MUTEX(idetape_ref_mutex);
222
223 static struct class *idetape_sysfs_class;
224
225 static void ide_tape_release(struct device *);
226
227 static struct ide_tape_obj *idetape_devs[MAX_HWIFS * MAX_DRIVES];
228
229 static struct ide_tape_obj *ide_tape_get(struct gendisk *disk, bool cdev,
230                                          unsigned int i)
231 {
232         struct ide_tape_obj *tape = NULL;
233
234         mutex_lock(&idetape_ref_mutex);
235
236         if (cdev)
237                 tape = idetape_devs[i];
238         else
239                 tape = ide_drv_g(disk, ide_tape_obj);
240
241         if (tape) {
242                 if (ide_device_get(tape->drive))
243                         tape = NULL;
244                 else
245                         get_device(&tape->dev);
246         }
247
248         mutex_unlock(&idetape_ref_mutex);
249         return tape;
250 }
251
252 static void ide_tape_put(struct ide_tape_obj *tape)
253 {
254         ide_drive_t *drive = tape->drive;
255
256         mutex_lock(&idetape_ref_mutex);
257         put_device(&tape->dev);
258         ide_device_put(drive);
259         mutex_unlock(&idetape_ref_mutex);
260 }
261
262 /*
263  * called on each failed packet command retry to analyze the request sense. We
264  * currently do not utilize this information.
265  */
266 static void idetape_analyze_error(ide_drive_t *drive)
267 {
268         idetape_tape_t *tape = drive->driver_data;
269         struct ide_atapi_pc *pc = drive->failed_pc;
270         struct request *rq = drive->hwif->rq;
271         u8 *sense = bio_data(rq->bio);
272
273         tape->sense_key = sense[2] & 0xF;
274         tape->asc       = sense[12];
275         tape->ascq      = sense[13];
276
277         ide_debug_log(IDE_DBG_FUNC,
278                       "cmd: 0x%x, sense key = %x, asc = %x, ascq = %x",
279                       rq->cmd[0], tape->sense_key, tape->asc, tape->ascq);
280
281         /* correct remaining bytes to transfer */
282         if (pc->flags & PC_FLAG_DMA_ERROR)
283                 rq->resid_len = tape->blk_size * get_unaligned_be32(&sense[3]);
284
285         /*
286          * If error was the result of a zero-length read or write command,
287          * with sense key=5, asc=0x22, ascq=0, let it slide.  Some drives
288          * (i.e. Seagate STT3401A Travan) don't support 0-length read/writes.
289          */
290         if ((pc->c[0] == READ_6 || pc->c[0] == WRITE_6)
291             /* length == 0 */
292             && pc->c[4] == 0 && pc->c[3] == 0 && pc->c[2] == 0) {
293                 if (tape->sense_key == 5) {
294                         /* don't report an error, everything's ok */
295                         pc->error = 0;
296                         /* don't retry read/write */
297                         pc->flags |= PC_FLAG_ABORT;
298                 }
299         }
300         if (pc->c[0] == READ_6 && (sense[2] & 0x80)) {
301                 pc->error = IDE_DRV_ERROR_FILEMARK;
302                 pc->flags |= PC_FLAG_ABORT;
303         }
304         if (pc->c[0] == WRITE_6) {
305                 if ((sense[2] & 0x40) || (tape->sense_key == 0xd
306                      && tape->asc == 0x0 && tape->ascq == 0x2)) {
307                         pc->error = IDE_DRV_ERROR_EOD;
308                         pc->flags |= PC_FLAG_ABORT;
309                 }
310         }
311         if (pc->c[0] == READ_6 || pc->c[0] == WRITE_6) {
312                 if (tape->sense_key == 8) {
313                         pc->error = IDE_DRV_ERROR_EOD;
314                         pc->flags |= PC_FLAG_ABORT;
315                 }
316                 if (!(pc->flags & PC_FLAG_ABORT) &&
317                     (blk_rq_bytes(rq) - rq->resid_len))
318                         pc->retries = IDETAPE_MAX_PC_RETRIES + 1;
319         }
320 }
321
322 static void ide_tape_handle_dsc(ide_drive_t *);
323
324 static int ide_tape_callback(ide_drive_t *drive, int dsc)
325 {
326         idetape_tape_t *tape = drive->driver_data;
327         struct ide_atapi_pc *pc = drive->pc;
328         struct request *rq = drive->hwif->rq;
329         int uptodate = pc->error ? 0 : 1;
330         int err = uptodate ? 0 : IDE_DRV_ERROR_GENERAL;
331
332         ide_debug_log(IDE_DBG_FUNC, "cmd: 0x%x, dsc: %d, err: %d", rq->cmd[0],
333                       dsc, err);
334
335         if (dsc)
336                 ide_tape_handle_dsc(drive);
337
338         if (drive->failed_pc == pc)
339                 drive->failed_pc = NULL;
340
341         if (pc->c[0] == REQUEST_SENSE) {
342                 if (uptodate)
343                         idetape_analyze_error(drive);
344                 else
345                         printk(KERN_ERR "ide-tape: Error in REQUEST SENSE "
346                                         "itself - Aborting request!\n");
347         } else if (pc->c[0] == READ_6 || pc->c[0] == WRITE_6) {
348                 unsigned int blocks =
349                         (blk_rq_bytes(rq) - rq->resid_len) / tape->blk_size;
350
351                 tape->avg_size += blocks * tape->blk_size;
352
353                 if (time_after_eq(jiffies, tape->avg_time + HZ)) {
354                         tape->avg_speed = tape->avg_size * HZ /
355                                 (jiffies - tape->avg_time) / 1024;
356                         tape->avg_size = 0;
357                         tape->avg_time = jiffies;
358                 }
359
360                 tape->first_frame += blocks;
361
362                 if (pc->error) {
363                         uptodate = 0;
364                         err = pc->error;
365                 }
366         }
367         rq->errors = err;
368
369         return uptodate;
370 }
371
372 /*
373  * Postpone the current request so that ide.c will be able to service requests
374  * from another device on the same port while we are polling for DSC.
375  */
376 static void ide_tape_stall_queue(ide_drive_t *drive)
377 {
378         idetape_tape_t *tape = drive->driver_data;
379
380         ide_debug_log(IDE_DBG_FUNC, "cmd: 0x%x, dsc_poll_freq: %lu",
381                       drive->hwif->rq->cmd[0], tape->dsc_poll_freq);
382
383         tape->postponed_rq = true;
384
385         ide_stall_queue(drive, tape->dsc_poll_freq);
386 }
387
388 static void ide_tape_handle_dsc(ide_drive_t *drive)
389 {
390         idetape_tape_t *tape = drive->driver_data;
391
392         /* Media access command */
393         tape->dsc_polling_start = jiffies;
394         tape->dsc_poll_freq = IDETAPE_DSC_MA_FAST;
395         tape->dsc_timeout = jiffies + IDETAPE_DSC_MA_TIMEOUT;
396         /* Allow ide.c to handle other requests */
397         ide_tape_stall_queue(drive);
398 }
399
400 /*
401  * Packet Command Interface
402  *
403  * The current Packet Command is available in drive->pc, and will not change
404  * until we finish handling it. Each packet command is associated with a
405  * callback function that will be called when the command is finished.
406  *
407  * The handling will be done in three stages:
408  *
409  * 1. ide_tape_issue_pc will send the packet command to the drive, and will set
410  * the interrupt handler to ide_pc_intr.
411  *
412  * 2. On each interrupt, ide_pc_intr will be called. This step will be
413  * repeated until the device signals us that no more interrupts will be issued.
414  *
415  * 3. ATAPI Tape media access commands have immediate status with a delayed
416  * process. In case of a successful initiation of a media access packet command,
417  * the DSC bit will be set when the actual execution of the command is finished.
418  * Since the tape drive will not issue an interrupt, we have to poll for this
419  * event. In this case, we define the request as "low priority request" by
420  * setting rq_status to IDETAPE_RQ_POSTPONED, set a timer to poll for DSC and
421  * exit the driver.
422  *
423  * ide.c will then give higher priority to requests which originate from the
424  * other device, until will change rq_status to RQ_ACTIVE.
425  *
426  * 4. When the packet command is finished, it will be checked for errors.
427  *
428  * 5. In case an error was found, we queue a request sense packet command in
429  * front of the request queue and retry the operation up to
430  * IDETAPE_MAX_PC_RETRIES times.
431  *
432  * 6. In case no error was found, or we decided to give up and not to retry
433  * again, the callback function will be called and then we will handle the next
434  * request.
435  */
436
437 static ide_startstop_t ide_tape_issue_pc(ide_drive_t *drive,
438                                          struct ide_cmd *cmd,
439                                          struct ide_atapi_pc *pc)
440 {
441         idetape_tape_t *tape = drive->driver_data;
442         struct request *rq = drive->hwif->rq;
443
444         if (drive->failed_pc == NULL && pc->c[0] != REQUEST_SENSE)
445                 drive->failed_pc = pc;
446
447         /* Set the current packet command */
448         drive->pc = pc;
449
450         if (pc->retries > IDETAPE_MAX_PC_RETRIES ||
451                 (pc->flags & PC_FLAG_ABORT)) {
452
453                 /*
454                  * We will "abort" retrying a packet command in case legitimate
455                  * error code was received (crossing a filemark, or end of the
456                  * media, for example).
457                  */
458                 if (!(pc->flags & PC_FLAG_ABORT)) {
459                         if (!(pc->c[0] == TEST_UNIT_READY &&
460                               tape->sense_key == 2 && tape->asc == 4 &&
461                              (tape->ascq == 1 || tape->ascq == 8))) {
462                                 printk(KERN_ERR "ide-tape: %s: I/O error, "
463                                                 "pc = %2x, key = %2x, "
464                                                 "asc = %2x, ascq = %2x\n",
465                                                 tape->name, pc->c[0],
466                                                 tape->sense_key, tape->asc,
467                                                 tape->ascq);
468                         }
469                         /* Giving up */
470                         pc->error = IDE_DRV_ERROR_GENERAL;
471                 }
472
473                 drive->failed_pc = NULL;
474                 drive->pc_callback(drive, 0);
475                 ide_complete_rq(drive, -EIO, blk_rq_bytes(rq));
476                 return ide_stopped;
477         }
478         ide_debug_log(IDE_DBG_SENSE, "retry #%d, cmd: 0x%02x", pc->retries,
479                       pc->c[0]);
480
481         pc->retries++;
482
483         return ide_issue_pc(drive, cmd);
484 }
485
486 /* A mode sense command is used to "sense" tape parameters. */
487 static void idetape_create_mode_sense_cmd(struct ide_atapi_pc *pc, u8 page_code)
488 {
489         ide_init_pc(pc);
490         pc->c[0] = MODE_SENSE;
491         if (page_code != IDETAPE_BLOCK_DESCRIPTOR)
492                 /* DBD = 1 - Don't return block descriptors */
493                 pc->c[1] = 8;
494         pc->c[2] = page_code;
495         /*
496          * Changed pc->c[3] to 0 (255 will at best return unused info).
497          *
498          * For SCSI this byte is defined as subpage instead of high byte
499          * of length and some IDE drives seem to interpret it this way
500          * and return an error when 255 is used.
501          */
502         pc->c[3] = 0;
503         /* We will just discard data in that case */
504         pc->c[4] = 255;
505         if (page_code == IDETAPE_BLOCK_DESCRIPTOR)
506                 pc->req_xfer = 12;
507         else if (page_code == IDETAPE_CAPABILITIES_PAGE)
508                 pc->req_xfer = 24;
509         else
510                 pc->req_xfer = 50;
511 }
512
513 static ide_startstop_t idetape_media_access_finished(ide_drive_t *drive)
514 {
515         ide_hwif_t *hwif = drive->hwif;
516         idetape_tape_t *tape = drive->driver_data;
517         struct ide_atapi_pc *pc = drive->pc;
518         u8 stat;
519
520         stat = hwif->tp_ops->read_status(hwif);
521
522         if (stat & ATA_DSC) {
523                 if (stat & ATA_ERR) {
524                         /* Error detected */
525                         if (pc->c[0] != TEST_UNIT_READY)
526                                 printk(KERN_ERR "ide-tape: %s: I/O error, ",
527                                                 tape->name);
528                         /* Retry operation */
529                         ide_retry_pc(drive);
530                         return ide_stopped;
531                 }
532                 pc->error = 0;
533         } else {
534                 pc->error = IDE_DRV_ERROR_GENERAL;
535                 drive->failed_pc = NULL;
536         }
537         drive->pc_callback(drive, 0);
538         return ide_stopped;
539 }
540
541 static void ide_tape_create_rw_cmd(idetape_tape_t *tape,
542                                    struct ide_atapi_pc *pc, struct request *rq,
543                                    u8 opcode)
544 {
545         unsigned int length = blk_rq_sectors(rq) / (tape->blk_size >> 9);
546
547         ide_init_pc(pc);
548         put_unaligned(cpu_to_be32(length), (unsigned int *) &pc->c[1]);
549         pc->c[1] = 1;
550
551         if (blk_rq_bytes(rq) == tape->buffer_size)
552                 pc->flags |= PC_FLAG_DMA_OK;
553
554         if (opcode == READ_6)
555                 pc->c[0] = READ_6;
556         else if (opcode == WRITE_6) {
557                 pc->c[0] = WRITE_6;
558                 pc->flags |= PC_FLAG_WRITING;
559         }
560
561         memcpy(rq->cmd, pc->c, 12);
562 }
563
564 static ide_startstop_t idetape_do_request(ide_drive_t *drive,
565                                           struct request *rq, sector_t block)
566 {
567         ide_hwif_t *hwif = drive->hwif;
568         idetape_tape_t *tape = drive->driver_data;
569         struct ide_atapi_pc *pc = NULL;
570         struct ide_cmd cmd;
571         u8 stat;
572
573         ide_debug_log(IDE_DBG_RQ, "cmd: 0x%x, sector: %llu, nr_sectors: %u",
574                       rq->cmd[0], (unsigned long long)blk_rq_pos(rq),
575                       blk_rq_sectors(rq));
576
577         BUG_ON(!(blk_special_request(rq) || blk_sense_request(rq)));
578
579         /* Retry a failed packet command */
580         if (drive->failed_pc && drive->pc->c[0] == REQUEST_SENSE) {
581                 pc = drive->failed_pc;
582                 goto out;
583         }
584
585         /*
586          * If the tape is still busy, postpone our request and service
587          * the other device meanwhile.
588          */
589         stat = hwif->tp_ops->read_status(hwif);
590
591         if ((drive->dev_flags & IDE_DFLAG_DSC_OVERLAP) == 0 &&
592             (rq->cmd[13] & REQ_IDETAPE_PC2) == 0)
593                 drive->atapi_flags |= IDE_AFLAG_IGNORE_DSC;
594
595         if (drive->dev_flags & IDE_DFLAG_POST_RESET) {
596                 drive->atapi_flags |= IDE_AFLAG_IGNORE_DSC;
597                 drive->dev_flags &= ~IDE_DFLAG_POST_RESET;
598         }
599
600         if (!(drive->atapi_flags & IDE_AFLAG_IGNORE_DSC) &&
601             !(stat & ATA_DSC)) {
602                 if (!tape->postponed_rq) {
603                         tape->dsc_polling_start = jiffies;
604                         tape->dsc_poll_freq = tape->best_dsc_rw_freq;
605                         tape->dsc_timeout = jiffies + IDETAPE_DSC_RW_TIMEOUT;
606                 } else if (time_after(jiffies, tape->dsc_timeout)) {
607                         printk(KERN_ERR "ide-tape: %s: DSC timeout\n",
608                                 tape->name);
609                         if (rq->cmd[13] & REQ_IDETAPE_PC2) {
610                                 idetape_media_access_finished(drive);
611                                 return ide_stopped;
612                         } else {
613                                 return ide_do_reset(drive);
614                         }
615                 } else if (time_after(jiffies,
616                                         tape->dsc_polling_start +
617                                         IDETAPE_DSC_MA_THRESHOLD))
618                         tape->dsc_poll_freq = IDETAPE_DSC_MA_SLOW;
619                 ide_tape_stall_queue(drive);
620                 return ide_stopped;
621         } else {
622                 drive->atapi_flags &= ~IDE_AFLAG_IGNORE_DSC;
623                 tape->postponed_rq = false;
624         }
625
626         if (rq->cmd[13] & REQ_IDETAPE_READ) {
627                 pc = &tape->queued_pc;
628                 ide_tape_create_rw_cmd(tape, pc, rq, READ_6);
629                 goto out;
630         }
631         if (rq->cmd[13] & REQ_IDETAPE_WRITE) {
632                 pc = &tape->queued_pc;
633                 ide_tape_create_rw_cmd(tape, pc, rq, WRITE_6);
634                 goto out;
635         }
636         if (rq->cmd[13] & REQ_IDETAPE_PC1) {
637                 pc = (struct ide_atapi_pc *)rq->special;
638                 rq->cmd[13] &= ~(REQ_IDETAPE_PC1);
639                 rq->cmd[13] |= REQ_IDETAPE_PC2;
640                 goto out;
641         }
642         if (rq->cmd[13] & REQ_IDETAPE_PC2) {
643                 idetape_media_access_finished(drive);
644                 return ide_stopped;
645         }
646         BUG();
647
648 out:
649         /* prepare sense request for this command */
650         ide_prep_sense(drive, rq);
651
652         memset(&cmd, 0, sizeof(cmd));
653
654         if (rq_data_dir(rq))
655                 cmd.tf_flags |= IDE_TFLAG_WRITE;
656
657         cmd.rq = rq;
658
659         ide_init_sg_cmd(&cmd, blk_rq_bytes(rq));
660         ide_map_sg(drive, &cmd);
661
662         return ide_tape_issue_pc(drive, &cmd, pc);
663 }
664
665 /*
666  * Write a filemark if write_filemark=1. Flush the device buffers without
667  * writing a filemark otherwise.
668  */
669 static void idetape_create_write_filemark_cmd(ide_drive_t *drive,
670                 struct ide_atapi_pc *pc, int write_filemark)
671 {
672         ide_init_pc(pc);
673         pc->c[0] = WRITE_FILEMARKS;
674         pc->c[4] = write_filemark;
675         pc->flags |= PC_FLAG_WAIT_FOR_DSC;
676 }
677
678 static int idetape_wait_ready(ide_drive_t *drive, unsigned long timeout)
679 {
680         idetape_tape_t *tape = drive->driver_data;
681         struct gendisk *disk = tape->disk;
682         int load_attempted = 0;
683
684         /* Wait for the tape to become ready */
685         set_bit(ilog2(IDE_AFLAG_MEDIUM_PRESENT), &drive->atapi_flags);
686         timeout += jiffies;
687         while (time_before(jiffies, timeout)) {
688                 if (ide_do_test_unit_ready(drive, disk) == 0)
689                         return 0;
690                 if ((tape->sense_key == 2 && tape->asc == 4 && tape->ascq == 2)
691                     || (tape->asc == 0x3A)) {
692                         /* no media */
693                         if (load_attempted)
694                                 return -ENOMEDIUM;
695                         ide_do_start_stop(drive, disk, IDETAPE_LU_LOAD_MASK);
696                         load_attempted = 1;
697                 /* not about to be ready */
698                 } else if (!(tape->sense_key == 2 && tape->asc == 4 &&
699                              (tape->ascq == 1 || tape->ascq == 8)))
700                         return -EIO;
701                 msleep(100);
702         }
703         return -EIO;
704 }
705
706 static int idetape_flush_tape_buffers(ide_drive_t *drive)
707 {
708         struct ide_tape_obj *tape = drive->driver_data;
709         struct ide_atapi_pc pc;
710         int rc;
711
712         idetape_create_write_filemark_cmd(drive, &pc, 0);
713         rc = ide_queue_pc_tail(drive, tape->disk, &pc, NULL, 0);
714         if (rc)
715                 return rc;
716         idetape_wait_ready(drive, 60 * 5 * HZ);
717         return 0;
718 }
719
720 static int ide_tape_read_position(ide_drive_t *drive)
721 {
722         idetape_tape_t *tape = drive->driver_data;
723         struct ide_atapi_pc pc;
724         u8 buf[20];
725
726         ide_debug_log(IDE_DBG_FUNC, "enter");
727
728         /* prep cmd */
729         ide_init_pc(&pc);
730         pc.c[0] = READ_POSITION;
731         pc.req_xfer = 20;
732
733         if (ide_queue_pc_tail(drive, tape->disk, &pc, buf, pc.req_xfer))
734                 return -1;
735
736         if (!pc.error) {
737                 ide_debug_log(IDE_DBG_FUNC, "BOP - %s",
738                                 (buf[0] & 0x80) ? "Yes" : "No");
739                 ide_debug_log(IDE_DBG_FUNC, "EOP - %s",
740                                 (buf[0] & 0x40) ? "Yes" : "No");
741
742                 if (buf[0] & 0x4) {
743                         printk(KERN_INFO "ide-tape: Block location is unknown"
744                                          "to the tape\n");
745                         clear_bit(ilog2(IDE_AFLAG_ADDRESS_VALID),
746                                   &drive->atapi_flags);
747                         return -1;
748                 } else {
749                         ide_debug_log(IDE_DBG_FUNC, "Block Location: %u",
750                                       be32_to_cpup((__be32 *)&buf[4]));
751
752                         tape->partition = buf[1];
753                         tape->first_frame = be32_to_cpup((__be32 *)&buf[4]);
754                         set_bit(ilog2(IDE_AFLAG_ADDRESS_VALID),
755                                 &drive->atapi_flags);
756                 }
757         }
758
759         return tape->first_frame;
760 }
761
762 static void idetape_create_locate_cmd(ide_drive_t *drive,
763                 struct ide_atapi_pc *pc,
764                 unsigned int block, u8 partition, int skip)
765 {
766         ide_init_pc(pc);
767         pc->c[0] = POSITION_TO_ELEMENT;
768         pc->c[1] = 2;
769         put_unaligned(cpu_to_be32(block), (unsigned int *) &pc->c[3]);
770         pc->c[8] = partition;
771         pc->flags |= PC_FLAG_WAIT_FOR_DSC;
772 }
773
774 static void __ide_tape_discard_merge_buffer(ide_drive_t *drive)
775 {
776         idetape_tape_t *tape = drive->driver_data;
777
778         if (tape->chrdev_dir != IDETAPE_DIR_READ)
779                 return;
780
781         clear_bit(ilog2(IDE_AFLAG_FILEMARK), &drive->atapi_flags);
782         tape->valid = 0;
783         if (tape->buf != NULL) {
784                 kfree(tape->buf);
785                 tape->buf = NULL;
786         }
787
788         tape->chrdev_dir = IDETAPE_DIR_NONE;
789 }
790
791 /*
792  * Position the tape to the requested block using the LOCATE packet command.
793  * A READ POSITION command is then issued to check where we are positioned. Like
794  * all higher level operations, we queue the commands at the tail of the request
795  * queue and wait for their completion.
796  */
797 static int idetape_position_tape(ide_drive_t *drive, unsigned int block,
798                 u8 partition, int skip)
799 {
800         idetape_tape_t *tape = drive->driver_data;
801         struct gendisk *disk = tape->disk;
802         int ret;
803         struct ide_atapi_pc pc;
804
805         if (tape->chrdev_dir == IDETAPE_DIR_READ)
806                 __ide_tape_discard_merge_buffer(drive);
807         idetape_wait_ready(drive, 60 * 5 * HZ);
808         idetape_create_locate_cmd(drive, &pc, block, partition, skip);
809         ret = ide_queue_pc_tail(drive, disk, &pc, NULL, 0);
810         if (ret)
811                 return ret;
812
813         ret = ide_tape_read_position(drive);
814         if (ret < 0)
815                 return ret;
816         return 0;
817 }
818
819 static void ide_tape_discard_merge_buffer(ide_drive_t *drive,
820                                           int restore_position)
821 {
822         idetape_tape_t *tape = drive->driver_data;
823         int seek, position;
824
825         __ide_tape_discard_merge_buffer(drive);
826         if (restore_position) {
827                 position = ide_tape_read_position(drive);
828                 seek = position > 0 ? position : 0;
829                 if (idetape_position_tape(drive, seek, 0, 0)) {
830                         printk(KERN_INFO "ide-tape: %s: position_tape failed in"
831                                          " %s\n", tape->name, __func__);
832                         return;
833                 }
834         }
835 }
836
837 /*
838  * Generate a read/write request for the block device interface and wait for it
839  * to be serviced.
840  */
841 static int idetape_queue_rw_tail(ide_drive_t *drive, int cmd, int size)
842 {
843         idetape_tape_t *tape = drive->driver_data;
844         struct request *rq;
845         int ret;
846
847         ide_debug_log(IDE_DBG_FUNC, "cmd: 0x%x, size: %d", cmd, size);
848
849         BUG_ON(cmd != REQ_IDETAPE_READ && cmd != REQ_IDETAPE_WRITE);
850         BUG_ON(size < 0 || size % tape->blk_size);
851
852         rq = blk_get_request(drive->queue, READ, __GFP_WAIT);
853         rq->cmd_type = REQ_TYPE_SPECIAL;
854         rq->cmd[13] = cmd;
855         rq->rq_disk = tape->disk;
856         rq->__sector = tape->first_frame;
857
858         if (size) {
859                 ret = blk_rq_map_kern(drive->queue, rq, tape->buf, size,
860                                       __GFP_WAIT);
861                 if (ret)
862                         goto out_put;
863         }
864
865         blk_execute_rq(drive->queue, tape->disk, rq, 0);
866
867         /* calculate the number of transferred bytes and update buffer state */
868         size -= rq->resid_len;
869         tape->cur = tape->buf;
870         if (cmd == REQ_IDETAPE_READ)
871                 tape->valid = size;
872         else
873                 tape->valid = 0;
874
875         ret = size;
876         if (rq->errors == IDE_DRV_ERROR_GENERAL)
877                 ret = -EIO;
878 out_put:
879         blk_put_request(rq);
880         return ret;
881 }
882
883 static void idetape_create_inquiry_cmd(struct ide_atapi_pc *pc)
884 {
885         ide_init_pc(pc);
886         pc->c[0] = INQUIRY;
887         pc->c[4] = 254;
888         pc->req_xfer = 254;
889 }
890
891 static void idetape_create_rewind_cmd(ide_drive_t *drive,
892                 struct ide_atapi_pc *pc)
893 {
894         ide_init_pc(pc);
895         pc->c[0] = REZERO_UNIT;
896         pc->flags |= PC_FLAG_WAIT_FOR_DSC;
897 }
898
899 static void idetape_create_erase_cmd(struct ide_atapi_pc *pc)
900 {
901         ide_init_pc(pc);
902         pc->c[0] = ERASE;
903         pc->c[1] = 1;
904         pc->flags |= PC_FLAG_WAIT_FOR_DSC;
905 }
906
907 static void idetape_create_space_cmd(struct ide_atapi_pc *pc, int count, u8 cmd)
908 {
909         ide_init_pc(pc);
910         pc->c[0] = SPACE;
911         put_unaligned(cpu_to_be32(count), (unsigned int *) &pc->c[1]);
912         pc->c[1] = cmd;
913         pc->flags |= PC_FLAG_WAIT_FOR_DSC;
914 }
915
916 static void ide_tape_flush_merge_buffer(ide_drive_t *drive)
917 {
918         idetape_tape_t *tape = drive->driver_data;
919
920         if (tape->chrdev_dir != IDETAPE_DIR_WRITE) {
921                 printk(KERN_ERR "ide-tape: bug: Trying to empty merge buffer"
922                                 " but we are not writing.\n");
923                 return;
924         }
925         if (tape->buf) {
926                 size_t aligned = roundup(tape->valid, tape->blk_size);
927
928                 memset(tape->cur, 0, aligned - tape->valid);
929                 idetape_queue_rw_tail(drive, REQ_IDETAPE_WRITE, aligned);
930                 kfree(tape->buf);
931                 tape->buf = NULL;
932         }
933         tape->chrdev_dir = IDETAPE_DIR_NONE;
934 }
935
936 static int idetape_init_rw(ide_drive_t *drive, int dir)
937 {
938         idetape_tape_t *tape = drive->driver_data;
939         int rc;
940
941         BUG_ON(dir != IDETAPE_DIR_READ && dir != IDETAPE_DIR_WRITE);
942
943         if (tape->chrdev_dir == dir)
944                 return 0;
945
946         if (tape->chrdev_dir == IDETAPE_DIR_READ)
947                 ide_tape_discard_merge_buffer(drive, 1);
948         else if (tape->chrdev_dir == IDETAPE_DIR_WRITE) {
949                 ide_tape_flush_merge_buffer(drive);
950                 idetape_flush_tape_buffers(drive);
951         }
952
953         if (tape->buf || tape->valid) {
954                 printk(KERN_ERR "ide-tape: valid should be 0 now\n");
955                 tape->valid = 0;
956         }
957
958         tape->buf = kmalloc(tape->buffer_size, GFP_KERNEL);
959         if (!tape->buf)
960                 return -ENOMEM;
961         tape->chrdev_dir = dir;
962         tape->cur = tape->buf;
963
964         /*
965          * Issue a 0 rw command to ensure that DSC handshake is
966          * switched from completion mode to buffer available mode.  No
967          * point in issuing this if DSC overlap isn't supported, some
968          * drives (Seagate STT3401A) will return an error.
969          */
970         if (drive->dev_flags & IDE_DFLAG_DSC_OVERLAP) {
971                 int cmd = dir == IDETAPE_DIR_READ ? REQ_IDETAPE_READ
972                                                   : REQ_IDETAPE_WRITE;
973
974                 rc = idetape_queue_rw_tail(drive, cmd, 0);
975                 if (rc < 0) {
976                         kfree(tape->buf);
977                         tape->buf = NULL;
978                         tape->chrdev_dir = IDETAPE_DIR_NONE;
979                         return rc;
980                 }
981         }
982
983         return 0;
984 }
985
986 static void idetape_pad_zeros(ide_drive_t *drive, int bcount)
987 {
988         idetape_tape_t *tape = drive->driver_data;
989
990         memset(tape->buf, 0, tape->buffer_size);
991
992         while (bcount) {
993                 unsigned int count = min(tape->buffer_size, bcount);
994
995                 idetape_queue_rw_tail(drive, REQ_IDETAPE_WRITE, count);
996                 bcount -= count;
997         }
998 }
999
1000 /*
1001  * Rewinds the tape to the Beginning Of the current Partition (BOP). We
1002  * currently support only one partition.
1003  */
1004 static int idetape_rewind_tape(ide_drive_t *drive)
1005 {
1006         struct ide_tape_obj *tape = drive->driver_data;
1007         struct gendisk *disk = tape->disk;
1008         struct ide_atapi_pc pc;
1009         int ret;
1010
1011         ide_debug_log(IDE_DBG_FUNC, "enter");
1012
1013         idetape_create_rewind_cmd(drive, &pc);
1014         ret = ide_queue_pc_tail(drive, disk, &pc, NULL, 0);
1015         if (ret)
1016                 return ret;
1017
1018         ret = ide_tape_read_position(drive);
1019         if (ret < 0)
1020                 return ret;
1021         return 0;
1022 }
1023
1024 /* mtio.h compatible commands should be issued to the chrdev interface. */
1025 static int idetape_blkdev_ioctl(ide_drive_t *drive, unsigned int cmd,
1026                                 unsigned long arg)
1027 {
1028         idetape_tape_t *tape = drive->driver_data;
1029         void __user *argp = (void __user *)arg;
1030
1031         struct idetape_config {
1032                 int dsc_rw_frequency;
1033                 int dsc_media_access_frequency;
1034                 int nr_stages;
1035         } config;
1036
1037         ide_debug_log(IDE_DBG_FUNC, "cmd: 0x%04x", cmd);
1038
1039         switch (cmd) {
1040         case 0x0340:
1041                 if (copy_from_user(&config, argp, sizeof(config)))
1042                         return -EFAULT;
1043                 tape->best_dsc_rw_freq = config.dsc_rw_frequency;
1044                 break;
1045         case 0x0350:
1046                 memset(&config, 0, sizeof(config));
1047                 config.dsc_rw_frequency = (int) tape->best_dsc_rw_freq;
1048                 config.nr_stages = 1;
1049                 if (copy_to_user(argp, &config, sizeof(config)))
1050                         return -EFAULT;
1051                 break;
1052         default:
1053                 return -EIO;
1054         }
1055         return 0;
1056 }
1057
1058 static int idetape_space_over_filemarks(ide_drive_t *drive, short mt_op,
1059                                         int mt_count)
1060 {
1061         idetape_tape_t *tape = drive->driver_data;
1062         struct gendisk *disk = tape->disk;
1063         struct ide_atapi_pc pc;
1064         int retval, count = 0;
1065         int sprev = !!(tape->caps[4] & 0x20);
1066
1067
1068         ide_debug_log(IDE_DBG_FUNC, "mt_op: %d, mt_count: %d", mt_op, mt_count);
1069
1070         if (mt_count == 0)
1071                 return 0;
1072         if (MTBSF == mt_op || MTBSFM == mt_op) {
1073                 if (!sprev)
1074                         return -EIO;
1075                 mt_count = -mt_count;
1076         }
1077
1078         if (tape->chrdev_dir == IDETAPE_DIR_READ) {
1079                 tape->valid = 0;
1080                 if (test_and_clear_bit(ilog2(IDE_AFLAG_FILEMARK),
1081                                        &drive->atapi_flags))
1082                         ++count;
1083                 ide_tape_discard_merge_buffer(drive, 0);
1084         }
1085
1086         switch (mt_op) {
1087         case MTFSF:
1088         case MTBSF:
1089                 idetape_create_space_cmd(&pc, mt_count - count,
1090                                          IDETAPE_SPACE_OVER_FILEMARK);
1091                 return ide_queue_pc_tail(drive, disk, &pc, NULL, 0);
1092         case MTFSFM:
1093         case MTBSFM:
1094                 if (!sprev)
1095                         return -EIO;
1096                 retval = idetape_space_over_filemarks(drive, MTFSF,
1097                                                       mt_count - count);
1098                 if (retval)
1099                         return retval;
1100                 count = (MTBSFM == mt_op ? 1 : -1);
1101                 return idetape_space_over_filemarks(drive, MTFSF, count);
1102         default:
1103                 printk(KERN_ERR "ide-tape: MTIO operation %d not supported\n",
1104                                 mt_op);
1105                 return -EIO;
1106         }
1107 }
1108
1109 /*
1110  * Our character device read / write functions.
1111  *
1112  * The tape is optimized to maximize throughput when it is transferring an
1113  * integral number of the "continuous transfer limit", which is a parameter of
1114  * the specific tape (26kB on my particular tape, 32kB for Onstream).
1115  *
1116  * As of version 1.3 of the driver, the character device provides an abstract
1117  * continuous view of the media - any mix of block sizes (even 1 byte) on the
1118  * same backup/restore procedure is supported. The driver will internally
1119  * convert the requests to the recommended transfer unit, so that an unmatch
1120  * between the user's block size to the recommended size will only result in a
1121  * (slightly) increased driver overhead, but will no longer hit performance.
1122  * This is not applicable to Onstream.
1123  */
1124 static ssize_t idetape_chrdev_read(struct file *file, char __user *buf,
1125                                    size_t count, loff_t *ppos)
1126 {
1127         struct ide_tape_obj *tape = file->private_data;
1128         ide_drive_t *drive = tape->drive;
1129         size_t done = 0;
1130         ssize_t ret = 0;
1131         int rc;
1132
1133         ide_debug_log(IDE_DBG_FUNC, "count %Zd", count);
1134
1135         if (tape->chrdev_dir != IDETAPE_DIR_READ) {
1136                 if (test_bit(ilog2(IDE_AFLAG_DETECT_BS), &drive->atapi_flags))
1137                         if (count > tape->blk_size &&
1138                             (count % tape->blk_size) == 0)
1139                                 tape->user_bs_factor = count / tape->blk_size;
1140         }
1141
1142         rc = idetape_init_rw(drive, IDETAPE_DIR_READ);
1143         if (rc < 0)
1144                 return rc;
1145
1146         while (done < count) {
1147                 size_t todo;
1148
1149                 /* refill if staging buffer is empty */
1150                 if (!tape->valid) {
1151                         /* If we are at a filemark, nothing more to read */
1152                         if (test_bit(ilog2(IDE_AFLAG_FILEMARK),
1153                                      &drive->atapi_flags))
1154                                 break;
1155                         /* read */
1156                         if (idetape_queue_rw_tail(drive, REQ_IDETAPE_READ,
1157                                                   tape->buffer_size) <= 0)
1158                                 break;
1159                 }
1160
1161                 /* copy out */
1162                 todo = min_t(size_t, count - done, tape->valid);
1163                 if (copy_to_user(buf + done, tape->cur, todo))
1164                         ret = -EFAULT;
1165
1166                 tape->cur += todo;
1167                 tape->valid -= todo;
1168                 done += todo;
1169         }
1170
1171         if (!done && test_bit(ilog2(IDE_AFLAG_FILEMARK), &drive->atapi_flags)) {
1172                 idetape_space_over_filemarks(drive, MTFSF, 1);
1173                 return 0;
1174         }
1175
1176         return ret ? ret : done;
1177 }
1178
1179 static ssize_t idetape_chrdev_write(struct file *file, const char __user *buf,
1180                                      size_t count, loff_t *ppos)
1181 {
1182         struct ide_tape_obj *tape = file->private_data;
1183         ide_drive_t *drive = tape->drive;
1184         size_t done = 0;
1185         ssize_t ret = 0;
1186         int rc;
1187
1188         /* The drive is write protected. */
1189         if (tape->write_prot)
1190                 return -EACCES;
1191
1192         ide_debug_log(IDE_DBG_FUNC, "count %Zd", count);
1193
1194         /* Initialize write operation */
1195         rc = idetape_init_rw(drive, IDETAPE_DIR_WRITE);
1196         if (rc < 0)
1197                 return rc;
1198
1199         while (done < count) {
1200                 size_t todo;
1201
1202                 /* flush if staging buffer is full */
1203                 if (tape->valid == tape->buffer_size &&
1204                     idetape_queue_rw_tail(drive, REQ_IDETAPE_WRITE,
1205                                           tape->buffer_size) <= 0)
1206                         return rc;
1207
1208                 /* copy in */
1209                 todo = min_t(size_t, count - done,
1210                              tape->buffer_size - tape->valid);
1211                 if (copy_from_user(tape->cur, buf + done, todo))
1212                         ret = -EFAULT;
1213
1214                 tape->cur += todo;
1215                 tape->valid += todo;
1216                 done += todo;
1217         }
1218
1219         return ret ? ret : done;
1220 }
1221
1222 static int idetape_write_filemark(ide_drive_t *drive)
1223 {
1224         struct ide_tape_obj *tape = drive->driver_data;
1225         struct ide_atapi_pc pc;
1226
1227         /* Write a filemark */
1228         idetape_create_write_filemark_cmd(drive, &pc, 1);
1229         if (ide_queue_pc_tail(drive, tape->disk, &pc, NULL, 0)) {
1230                 printk(KERN_ERR "ide-tape: Couldn't write a filemark\n");
1231                 return -EIO;
1232         }
1233         return 0;
1234 }
1235
1236 /*
1237  * Called from idetape_chrdev_ioctl when the general mtio MTIOCTOP ioctl is
1238  * requested.
1239  *
1240  * Note: MTBSF and MTBSFM are not supported when the tape doesn't support
1241  * spacing over filemarks in the reverse direction. In this case, MTFSFM is also
1242  * usually not supported.
1243  *
1244  * The following commands are currently not supported:
1245  *
1246  * MTFSS, MTBSS, MTWSM, MTSETDENSITY, MTSETDRVBUFFER, MT_ST_BOOLEANS,
1247  * MT_ST_WRITE_THRESHOLD.
1248  */
1249 static int idetape_mtioctop(ide_drive_t *drive, short mt_op, int mt_count)
1250 {
1251         idetape_tape_t *tape = drive->driver_data;
1252         struct gendisk *disk = tape->disk;
1253         struct ide_atapi_pc pc;
1254         int i, retval;
1255
1256         ide_debug_log(IDE_DBG_FUNC, "MTIOCTOP ioctl: mt_op: %d, mt_count: %d",
1257                       mt_op, mt_count);
1258
1259         switch (mt_op) {
1260         case MTFSF:
1261         case MTFSFM:
1262         case MTBSF:
1263         case MTBSFM:
1264                 if (!mt_count)
1265                         return 0;
1266                 return idetape_space_over_filemarks(drive, mt_op, mt_count);
1267         default:
1268                 break;
1269         }
1270
1271         switch (mt_op) {
1272         case MTWEOF:
1273                 if (tape->write_prot)
1274                         return -EACCES;
1275                 ide_tape_discard_merge_buffer(drive, 1);
1276                 for (i = 0; i < mt_count; i++) {
1277                         retval = idetape_write_filemark(drive);
1278                         if (retval)
1279                                 return retval;
1280                 }
1281                 return 0;
1282         case MTREW:
1283                 ide_tape_discard_merge_buffer(drive, 0);
1284                 if (idetape_rewind_tape(drive))
1285                         return -EIO;
1286                 return 0;
1287         case MTLOAD:
1288                 ide_tape_discard_merge_buffer(drive, 0);
1289                 return ide_do_start_stop(drive, disk, IDETAPE_LU_LOAD_MASK);
1290         case MTUNLOAD:
1291         case MTOFFL:
1292                 /*
1293                  * If door is locked, attempt to unlock before
1294                  * attempting to eject.
1295                  */
1296                 if (tape->door_locked) {
1297                         if (!ide_set_media_lock(drive, disk, 0))
1298                                 tape->door_locked = DOOR_UNLOCKED;
1299                 }
1300                 ide_tape_discard_merge_buffer(drive, 0);
1301                 retval = ide_do_start_stop(drive, disk, !IDETAPE_LU_LOAD_MASK);
1302                 if (!retval)
1303                         clear_bit(ilog2(IDE_AFLAG_MEDIUM_PRESENT),
1304                                   &drive->atapi_flags);
1305                 return retval;
1306         case MTNOP:
1307                 ide_tape_discard_merge_buffer(drive, 0);
1308                 return idetape_flush_tape_buffers(drive);
1309         case MTRETEN:
1310                 ide_tape_discard_merge_buffer(drive, 0);
1311                 return ide_do_start_stop(drive, disk,
1312                         IDETAPE_LU_RETENSION_MASK | IDETAPE_LU_LOAD_MASK);
1313         case MTEOM:
1314                 idetape_create_space_cmd(&pc, 0, IDETAPE_SPACE_TO_EOD);
1315                 return ide_queue_pc_tail(drive, disk, &pc, NULL, 0);
1316         case MTERASE:
1317                 (void)idetape_rewind_tape(drive);
1318                 idetape_create_erase_cmd(&pc);
1319                 return ide_queue_pc_tail(drive, disk, &pc, NULL, 0);
1320         case MTSETBLK:
1321                 if (mt_count) {
1322                         if (mt_count < tape->blk_size ||
1323                             mt_count % tape->blk_size)
1324                                 return -EIO;
1325                         tape->user_bs_factor = mt_count / tape->blk_size;
1326                         clear_bit(ilog2(IDE_AFLAG_DETECT_BS),
1327                                   &drive->atapi_flags);
1328                 } else
1329                         set_bit(ilog2(IDE_AFLAG_DETECT_BS),
1330                                 &drive->atapi_flags);
1331                 return 0;
1332         case MTSEEK:
1333                 ide_tape_discard_merge_buffer(drive, 0);
1334                 return idetape_position_tape(drive,
1335                         mt_count * tape->user_bs_factor, tape->partition, 0);
1336         case MTSETPART:
1337                 ide_tape_discard_merge_buffer(drive, 0);
1338                 return idetape_position_tape(drive, 0, mt_count, 0);
1339         case MTFSR:
1340         case MTBSR:
1341         case MTLOCK:
1342                 retval = ide_set_media_lock(drive, disk, 1);
1343                 if (retval)
1344                         return retval;
1345                 tape->door_locked = DOOR_EXPLICITLY_LOCKED;
1346                 return 0;
1347         case MTUNLOCK:
1348                 retval = ide_set_media_lock(drive, disk, 0);
1349                 if (retval)
1350                         return retval;
1351                 tape->door_locked = DOOR_UNLOCKED;
1352                 return 0;
1353         default:
1354                 printk(KERN_ERR "ide-tape: MTIO operation %d not supported\n",
1355                                 mt_op);
1356                 return -EIO;
1357         }
1358 }
1359
1360 /*
1361  * Our character device ioctls. General mtio.h magnetic io commands are
1362  * supported here, and not in the corresponding block interface. Our own
1363  * ide-tape ioctls are supported on both interfaces.
1364  */
1365 static int idetape_chrdev_ioctl(struct inode *inode, struct file *file,
1366                                 unsigned int cmd, unsigned long arg)
1367 {
1368         struct ide_tape_obj *tape = file->private_data;
1369         ide_drive_t *drive = tape->drive;
1370         struct mtop mtop;
1371         struct mtget mtget;
1372         struct mtpos mtpos;
1373         int block_offset = 0, position = tape->first_frame;
1374         void __user *argp = (void __user *)arg;
1375
1376         ide_debug_log(IDE_DBG_FUNC, "cmd: 0x%x", cmd);
1377
1378         if (tape->chrdev_dir == IDETAPE_DIR_WRITE) {
1379                 ide_tape_flush_merge_buffer(drive);
1380                 idetape_flush_tape_buffers(drive);
1381         }
1382         if (cmd == MTIOCGET || cmd == MTIOCPOS) {
1383                 block_offset = tape->valid /
1384                         (tape->blk_size * tape->user_bs_factor);
1385                 position = ide_tape_read_position(drive);
1386                 if (position < 0)
1387                         return -EIO;
1388         }
1389         switch (cmd) {
1390         case MTIOCTOP:
1391                 if (copy_from_user(&mtop, argp, sizeof(struct mtop)))
1392                         return -EFAULT;
1393                 return idetape_mtioctop(drive, mtop.mt_op, mtop.mt_count);
1394         case MTIOCGET:
1395                 memset(&mtget, 0, sizeof(struct mtget));
1396                 mtget.mt_type = MT_ISSCSI2;
1397                 mtget.mt_blkno = position / tape->user_bs_factor - block_offset;
1398                 mtget.mt_dsreg =
1399                         ((tape->blk_size * tape->user_bs_factor)
1400                          << MT_ST_BLKSIZE_SHIFT) & MT_ST_BLKSIZE_MASK;
1401
1402                 if (tape->drv_write_prot)
1403                         mtget.mt_gstat |= GMT_WR_PROT(0xffffffff);
1404
1405                 if (copy_to_user(argp, &mtget, sizeof(struct mtget)))
1406                         return -EFAULT;
1407                 return 0;
1408         case MTIOCPOS:
1409                 mtpos.mt_blkno = position / tape->user_bs_factor - block_offset;
1410                 if (copy_to_user(argp, &mtpos, sizeof(struct mtpos)))
1411                         return -EFAULT;
1412                 return 0;
1413         default:
1414                 if (tape->chrdev_dir == IDETAPE_DIR_READ)
1415                         ide_tape_discard_merge_buffer(drive, 1);
1416                 return idetape_blkdev_ioctl(drive, cmd, arg);
1417         }
1418 }
1419
1420 /*
1421  * Do a mode sense page 0 with block descriptor and if it succeeds set the tape
1422  * block size with the reported value.
1423  */
1424 static void ide_tape_get_bsize_from_bdesc(ide_drive_t *drive)
1425 {
1426         idetape_tape_t *tape = drive->driver_data;
1427         struct ide_atapi_pc pc;
1428         u8 buf[12];
1429
1430         idetape_create_mode_sense_cmd(&pc, IDETAPE_BLOCK_DESCRIPTOR);
1431         if (ide_queue_pc_tail(drive, tape->disk, &pc, buf, pc.req_xfer)) {
1432                 printk(KERN_ERR "ide-tape: Can't get block descriptor\n");
1433                 if (tape->blk_size == 0) {
1434                         printk(KERN_WARNING "ide-tape: Cannot deal with zero "
1435                                             "block size, assuming 32k\n");
1436                         tape->blk_size = 32768;
1437                 }
1438                 return;
1439         }
1440         tape->blk_size = (buf[4 + 5] << 16) +
1441                                 (buf[4 + 6] << 8)  +
1442                                  buf[4 + 7];
1443         tape->drv_write_prot = (buf[2] & 0x80) >> 7;
1444
1445         ide_debug_log(IDE_DBG_FUNC, "blk_size: %d, write_prot: %d",
1446                       tape->blk_size, tape->drv_write_prot);
1447 }
1448
1449 static int idetape_chrdev_open(struct inode *inode, struct file *filp)
1450 {
1451         unsigned int minor = iminor(inode), i = minor & ~0xc0;
1452         ide_drive_t *drive;
1453         idetape_tape_t *tape;
1454         int retval;
1455
1456         if (i >= MAX_HWIFS * MAX_DRIVES)
1457                 return -ENXIO;
1458
1459         lock_kernel();
1460         tape = ide_tape_get(NULL, true, i);
1461         if (!tape) {
1462                 unlock_kernel();
1463                 return -ENXIO;
1464         }
1465
1466         drive = tape->drive;
1467         filp->private_data = tape;
1468
1469         ide_debug_log(IDE_DBG_FUNC, "enter");
1470
1471         /*
1472          * We really want to do nonseekable_open(inode, filp); here, but some
1473          * versions of tar incorrectly call lseek on tapes and bail out if that
1474          * fails.  So we disallow pread() and pwrite(), but permit lseeks.
1475          */
1476         filp->f_mode &= ~(FMODE_PREAD | FMODE_PWRITE);
1477
1478
1479         if (test_and_set_bit(ilog2(IDE_AFLAG_BUSY), &drive->atapi_flags)) {
1480                 retval = -EBUSY;
1481                 goto out_put_tape;
1482         }
1483
1484         retval = idetape_wait_ready(drive, 60 * HZ);
1485         if (retval) {
1486                 clear_bit(ilog2(IDE_AFLAG_BUSY), &drive->atapi_flags);
1487                 printk(KERN_ERR "ide-tape: %s: drive not ready\n", tape->name);
1488                 goto out_put_tape;
1489         }
1490
1491         ide_tape_read_position(drive);
1492         if (!test_bit(ilog2(IDE_AFLAG_ADDRESS_VALID), &drive->atapi_flags))
1493                 (void)idetape_rewind_tape(drive);
1494
1495         /* Read block size and write protect status from drive. */
1496         ide_tape_get_bsize_from_bdesc(drive);
1497
1498         /* Set write protect flag if device is opened as read-only. */
1499         if ((filp->f_flags & O_ACCMODE) == O_RDONLY)
1500                 tape->write_prot = 1;
1501         else
1502                 tape->write_prot = tape->drv_write_prot;
1503
1504         /* Make sure drive isn't write protected if user wants to write. */
1505         if (tape->write_prot) {
1506                 if ((filp->f_flags & O_ACCMODE) == O_WRONLY ||
1507                     (filp->f_flags & O_ACCMODE) == O_RDWR) {
1508                         clear_bit(ilog2(IDE_AFLAG_BUSY), &drive->atapi_flags);
1509                         retval = -EROFS;
1510                         goto out_put_tape;
1511                 }
1512         }
1513
1514         /* Lock the tape drive door so user can't eject. */
1515         if (tape->chrdev_dir == IDETAPE_DIR_NONE) {
1516                 if (!ide_set_media_lock(drive, tape->disk, 1)) {
1517                         if (tape->door_locked != DOOR_EXPLICITLY_LOCKED)
1518                                 tape->door_locked = DOOR_LOCKED;
1519                 }
1520         }
1521         unlock_kernel();
1522         return 0;
1523
1524 out_put_tape:
1525         ide_tape_put(tape);
1526         unlock_kernel();
1527         return retval;
1528 }
1529
1530 static void idetape_write_release(ide_drive_t *drive, unsigned int minor)
1531 {
1532         idetape_tape_t *tape = drive->driver_data;
1533
1534         ide_tape_flush_merge_buffer(drive);
1535         tape->buf = kmalloc(tape->buffer_size, GFP_KERNEL);
1536         if (tape->buf != NULL) {
1537                 idetape_pad_zeros(drive, tape->blk_size *
1538                                 (tape->user_bs_factor - 1));
1539                 kfree(tape->buf);
1540                 tape->buf = NULL;
1541         }
1542         idetape_write_filemark(drive);
1543         idetape_flush_tape_buffers(drive);
1544         idetape_flush_tape_buffers(drive);
1545 }
1546
1547 static int idetape_chrdev_release(struct inode *inode, struct file *filp)
1548 {
1549         struct ide_tape_obj *tape = filp->private_data;
1550         ide_drive_t *drive = tape->drive;
1551         unsigned int minor = iminor(inode);
1552
1553         lock_kernel();
1554         tape = drive->driver_data;
1555
1556         ide_debug_log(IDE_DBG_FUNC, "enter");
1557
1558         if (tape->chrdev_dir == IDETAPE_DIR_WRITE)
1559                 idetape_write_release(drive, minor);
1560         if (tape->chrdev_dir == IDETAPE_DIR_READ) {
1561                 if (minor < 128)
1562                         ide_tape_discard_merge_buffer(drive, 1);
1563         }
1564
1565         if (minor < 128 && test_bit(ilog2(IDE_AFLAG_MEDIUM_PRESENT),
1566                                     &drive->atapi_flags))
1567                 (void) idetape_rewind_tape(drive);
1568
1569         if (tape->chrdev_dir == IDETAPE_DIR_NONE) {
1570                 if (tape->door_locked == DOOR_LOCKED) {
1571                         if (!ide_set_media_lock(drive, tape->disk, 0))
1572                                 tape->door_locked = DOOR_UNLOCKED;
1573                 }
1574         }
1575         clear_bit(ilog2(IDE_AFLAG_BUSY), &drive->atapi_flags);
1576         ide_tape_put(tape);
1577         unlock_kernel();
1578         return 0;
1579 }
1580
1581 static void idetape_get_inquiry_results(ide_drive_t *drive)
1582 {
1583         idetape_tape_t *tape = drive->driver_data;
1584         struct ide_atapi_pc pc;
1585         u8 pc_buf[256];
1586         char fw_rev[4], vendor_id[8], product_id[16];
1587
1588         idetape_create_inquiry_cmd(&pc);
1589         if (ide_queue_pc_tail(drive, tape->disk, &pc, pc_buf, pc.req_xfer)) {
1590                 printk(KERN_ERR "ide-tape: %s: can't get INQUIRY results\n",
1591                                 tape->name);
1592                 return;
1593         }
1594         memcpy(vendor_id, &pc_buf[8], 8);
1595         memcpy(product_id, &pc_buf[16], 16);
1596         memcpy(fw_rev, &pc_buf[32], 4);
1597
1598         ide_fixstring(vendor_id, 8, 0);
1599         ide_fixstring(product_id, 16, 0);
1600         ide_fixstring(fw_rev, 4, 0);
1601
1602         printk(KERN_INFO "ide-tape: %s <-> %s: %.8s %.16s rev %.4s\n",
1603                         drive->name, tape->name, vendor_id, product_id, fw_rev);
1604 }
1605
1606 /*
1607  * Ask the tape about its various parameters. In particular, we will adjust our
1608  * data transfer buffer size to the recommended value as returned by the tape.
1609  */
1610 static void idetape_get_mode_sense_results(ide_drive_t *drive)
1611 {
1612         idetape_tape_t *tape = drive->driver_data;
1613         struct ide_atapi_pc pc;
1614         u8 buf[24], *caps;
1615         u8 speed, max_speed;
1616
1617         idetape_create_mode_sense_cmd(&pc, IDETAPE_CAPABILITIES_PAGE);
1618         if (ide_queue_pc_tail(drive, tape->disk, &pc, buf, pc.req_xfer)) {
1619                 printk(KERN_ERR "ide-tape: Can't get tape parameters - assuming"
1620                                 " some default values\n");
1621                 tape->blk_size = 512;
1622                 put_unaligned(52,   (u16 *)&tape->caps[12]);
1623                 put_unaligned(540,  (u16 *)&tape->caps[14]);
1624                 put_unaligned(6*52, (u16 *)&tape->caps[16]);
1625                 return;
1626         }
1627         caps = buf + 4 + buf[3];
1628
1629         /* convert to host order and save for later use */
1630         speed = be16_to_cpup((__be16 *)&caps[14]);
1631         max_speed = be16_to_cpup((__be16 *)&caps[8]);
1632
1633         *(u16 *)&caps[8] = max_speed;
1634         *(u16 *)&caps[12] = be16_to_cpup((__be16 *)&caps[12]);
1635         *(u16 *)&caps[14] = speed;
1636         *(u16 *)&caps[16] = be16_to_cpup((__be16 *)&caps[16]);
1637
1638         if (!speed) {
1639                 printk(KERN_INFO "ide-tape: %s: invalid tape speed "
1640                                 "(assuming 650KB/sec)\n", drive->name);
1641                 *(u16 *)&caps[14] = 650;
1642         }
1643         if (!max_speed) {
1644                 printk(KERN_INFO "ide-tape: %s: invalid max_speed "
1645                                 "(assuming 650KB/sec)\n", drive->name);
1646                 *(u16 *)&caps[8] = 650;
1647         }
1648
1649         memcpy(&tape->caps, caps, 20);
1650
1651         /* device lacks locking support according to capabilities page */
1652         if ((caps[6] & 1) == 0)
1653                 drive->dev_flags &= ~IDE_DFLAG_DOORLOCKING;
1654
1655         if (caps[7] & 0x02)
1656                 tape->blk_size = 512;
1657         else if (caps[7] & 0x04)
1658                 tape->blk_size = 1024;
1659 }
1660
1661 #ifdef CONFIG_IDE_PROC_FS
1662 #define ide_tape_devset_get(name, field) \
1663 static int get_##name(ide_drive_t *drive) \
1664 { \
1665         idetape_tape_t *tape = drive->driver_data; \
1666         return tape->field; \
1667 }
1668
1669 #define ide_tape_devset_set(name, field) \
1670 static int set_##name(ide_drive_t *drive, int arg) \
1671 { \
1672         idetape_tape_t *tape = drive->driver_data; \
1673         tape->field = arg; \
1674         return 0; \
1675 }
1676
1677 #define ide_tape_devset_rw_field(_name, _field) \
1678 ide_tape_devset_get(_name, _field) \
1679 ide_tape_devset_set(_name, _field) \
1680 IDE_DEVSET(_name, DS_SYNC, get_##_name, set_##_name)
1681
1682 #define ide_tape_devset_r_field(_name, _field) \
1683 ide_tape_devset_get(_name, _field) \
1684 IDE_DEVSET(_name, 0, get_##_name, NULL)
1685
1686 static int mulf_tdsc(ide_drive_t *drive)        { return 1000; }
1687 static int divf_tdsc(ide_drive_t *drive)        { return   HZ; }
1688 static int divf_buffer(ide_drive_t *drive)      { return    2; }
1689 static int divf_buffer_size(ide_drive_t *drive) { return 1024; }
1690
1691 ide_devset_rw_flag(dsc_overlap, IDE_DFLAG_DSC_OVERLAP);
1692
1693 ide_tape_devset_rw_field(tdsc, best_dsc_rw_freq);
1694
1695 ide_tape_devset_r_field(avg_speed, avg_speed);
1696 ide_tape_devset_r_field(speed, caps[14]);
1697 ide_tape_devset_r_field(buffer, caps[16]);
1698 ide_tape_devset_r_field(buffer_size, buffer_size);
1699
1700 static const struct ide_proc_devset idetape_settings[] = {
1701         __IDE_PROC_DEVSET(avg_speed,    0, 0xffff, NULL, NULL),
1702         __IDE_PROC_DEVSET(buffer,       0, 0xffff, NULL, divf_buffer),
1703         __IDE_PROC_DEVSET(buffer_size,  0, 0xffff, NULL, divf_buffer_size),
1704         __IDE_PROC_DEVSET(dsc_overlap,  0,      1, NULL, NULL),
1705         __IDE_PROC_DEVSET(speed,        0, 0xffff, NULL, NULL),
1706         __IDE_PROC_DEVSET(tdsc,         IDETAPE_DSC_RW_MIN, IDETAPE_DSC_RW_MAX,
1707                                         mulf_tdsc, divf_tdsc),
1708         { NULL },
1709 };
1710 #endif
1711
1712 /*
1713  * The function below is called to:
1714  *
1715  * 1. Initialize our various state variables.
1716  * 2. Ask the tape for its capabilities.
1717  * 3. Allocate a buffer which will be used for data transfer. The buffer size
1718  * is chosen based on the recommendation which we received in step 2.
1719  *
1720  * Note that at this point ide.c already assigned us an irq, so that we can
1721  * queue requests here and wait for their completion.
1722  */
1723 static void idetape_setup(ide_drive_t *drive, idetape_tape_t *tape, int minor)
1724 {
1725         unsigned long t;
1726         int speed;
1727         int buffer_size;
1728         u16 *ctl = (u16 *)&tape->caps[12];
1729
1730         ide_debug_log(IDE_DBG_FUNC, "minor: %d", minor);
1731
1732         drive->pc_callback = ide_tape_callback;
1733
1734         drive->dev_flags |= IDE_DFLAG_DSC_OVERLAP;
1735
1736         if (drive->hwif->host_flags & IDE_HFLAG_NO_DSC) {
1737                 printk(KERN_INFO "ide-tape: %s: disabling DSC overlap\n",
1738                                  tape->name);
1739                 drive->dev_flags &= ~IDE_DFLAG_DSC_OVERLAP;
1740         }
1741
1742         /* Seagate Travan drives do not support DSC overlap. */
1743         if (strstr((char *)&drive->id[ATA_ID_PROD], "Seagate STT3401"))
1744                 drive->dev_flags &= ~IDE_DFLAG_DSC_OVERLAP;
1745
1746         tape->minor = minor;
1747         tape->name[0] = 'h';
1748         tape->name[1] = 't';
1749         tape->name[2] = '0' + minor;
1750         tape->chrdev_dir = IDETAPE_DIR_NONE;
1751
1752         idetape_get_inquiry_results(drive);
1753         idetape_get_mode_sense_results(drive);
1754         ide_tape_get_bsize_from_bdesc(drive);
1755         tape->user_bs_factor = 1;
1756         tape->buffer_size = *ctl * tape->blk_size;
1757         while (tape->buffer_size > 0xffff) {
1758                 printk(KERN_NOTICE "ide-tape: decreasing stage size\n");
1759                 *ctl /= 2;
1760                 tape->buffer_size = *ctl * tape->blk_size;
1761         }
1762         buffer_size = tape->buffer_size;
1763
1764         /* select the "best" DSC read/write polling freq */
1765         speed = max(*(u16 *)&tape->caps[14], *(u16 *)&tape->caps[8]);
1766
1767         t = (IDETAPE_FIFO_THRESHOLD * tape->buffer_size * HZ) / (speed * 1000);
1768
1769         /*
1770          * Ensure that the number we got makes sense; limit it within
1771          * IDETAPE_DSC_RW_MIN and IDETAPE_DSC_RW_MAX.
1772          */
1773         tape->best_dsc_rw_freq = clamp_t(unsigned long, t, IDETAPE_DSC_RW_MIN,
1774                                          IDETAPE_DSC_RW_MAX);
1775         printk(KERN_INFO "ide-tape: %s <-> %s: %dKBps, %d*%dkB buffer, "
1776                 "%lums tDSC%s\n",
1777                 drive->name, tape->name, *(u16 *)&tape->caps[14],
1778                 (*(u16 *)&tape->caps[16] * 512) / tape->buffer_size,
1779                 tape->buffer_size / 1024,
1780                 tape->best_dsc_rw_freq * 1000 / HZ,
1781                 (drive->dev_flags & IDE_DFLAG_USING_DMA) ? ", DMA" : "");
1782
1783         ide_proc_register_driver(drive, tape->driver);
1784 }
1785
1786 static void ide_tape_remove(ide_drive_t *drive)
1787 {
1788         idetape_tape_t *tape = drive->driver_data;
1789
1790         ide_proc_unregister_driver(drive, tape->driver);
1791         device_del(&tape->dev);
1792         ide_unregister_region(tape->disk);
1793
1794         mutex_lock(&idetape_ref_mutex);
1795         put_device(&tape->dev);
1796         mutex_unlock(&idetape_ref_mutex);
1797 }
1798
1799 static void ide_tape_release(struct device *dev)
1800 {
1801         struct ide_tape_obj *tape = to_ide_drv(dev, ide_tape_obj);
1802         ide_drive_t *drive = tape->drive;
1803         struct gendisk *g = tape->disk;
1804
1805         BUG_ON(tape->valid);
1806
1807         drive->dev_flags &= ~IDE_DFLAG_DSC_OVERLAP;
1808         drive->driver_data = NULL;
1809         device_destroy(idetape_sysfs_class, MKDEV(IDETAPE_MAJOR, tape->minor));
1810         device_destroy(idetape_sysfs_class,
1811                         MKDEV(IDETAPE_MAJOR, tape->minor + 128));
1812         idetape_devs[tape->minor] = NULL;
1813         g->private_data = NULL;
1814         put_disk(g);
1815         kfree(tape);
1816 }
1817
1818 #ifdef CONFIG_IDE_PROC_FS
1819 static int proc_idetape_read_name
1820         (char *page, char **start, off_t off, int count, int *eof, void *data)
1821 {
1822         ide_drive_t     *drive = (ide_drive_t *) data;
1823         idetape_tape_t  *tape = drive->driver_data;
1824         char            *out = page;
1825         int             len;
1826
1827         len = sprintf(out, "%s\n", tape->name);
1828         PROC_IDE_READ_RETURN(page, start, off, count, eof, len);
1829 }
1830
1831 static ide_proc_entry_t idetape_proc[] = {
1832         { "capacity",   S_IFREG|S_IRUGO,        proc_ide_read_capacity, NULL },
1833         { "name",       S_IFREG|S_IRUGO,        proc_idetape_read_name, NULL },
1834         { NULL, 0, NULL, NULL }
1835 };
1836
1837 static ide_proc_entry_t *ide_tape_proc_entries(ide_drive_t *drive)
1838 {
1839         return idetape_proc;
1840 }
1841
1842 static const struct ide_proc_devset *ide_tape_proc_devsets(ide_drive_t *drive)
1843 {
1844         return idetape_settings;
1845 }
1846 #endif
1847
1848 static int ide_tape_probe(ide_drive_t *);
1849
1850 static struct ide_driver idetape_driver = {
1851         .gen_driver = {
1852                 .owner          = THIS_MODULE,
1853                 .name           = "ide-tape",
1854                 .bus            = &ide_bus_type,
1855         },
1856         .probe                  = ide_tape_probe,
1857         .remove                 = ide_tape_remove,
1858         .version                = IDETAPE_VERSION,
1859         .do_request             = idetape_do_request,
1860 #ifdef CONFIG_IDE_PROC_FS
1861         .proc_entries           = ide_tape_proc_entries,
1862         .proc_devsets           = ide_tape_proc_devsets,
1863 #endif
1864 };
1865
1866 /* Our character device supporting functions, passed to register_chrdev. */
1867 static const struct file_operations idetape_fops = {
1868         .owner          = THIS_MODULE,
1869         .read           = idetape_chrdev_read,
1870         .write          = idetape_chrdev_write,
1871         .ioctl          = idetape_chrdev_ioctl,
1872         .open           = idetape_chrdev_open,
1873         .release        = idetape_chrdev_release,
1874 };
1875
1876 static int idetape_open(struct block_device *bdev, fmode_t mode)
1877 {
1878         struct ide_tape_obj *tape = ide_tape_get(bdev->bd_disk, false, 0);
1879
1880         if (!tape)
1881                 return -ENXIO;
1882
1883         return 0;
1884 }
1885
1886 static int idetape_release(struct gendisk *disk, fmode_t mode)
1887 {
1888         struct ide_tape_obj *tape = ide_drv_g(disk, ide_tape_obj);
1889
1890         ide_tape_put(tape);
1891         return 0;
1892 }
1893
1894 static int idetape_ioctl(struct block_device *bdev, fmode_t mode,
1895                         unsigned int cmd, unsigned long arg)
1896 {
1897         struct ide_tape_obj *tape = ide_drv_g(bdev->bd_disk, ide_tape_obj);
1898         ide_drive_t *drive = tape->drive;
1899         int err = generic_ide_ioctl(drive, bdev, cmd, arg);
1900         if (err == -EINVAL)
1901                 err = idetape_blkdev_ioctl(drive, cmd, arg);
1902         return err;
1903 }
1904
1905 static struct block_device_operations idetape_block_ops = {
1906         .owner          = THIS_MODULE,
1907         .open           = idetape_open,
1908         .release        = idetape_release,
1909         .locked_ioctl   = idetape_ioctl,
1910 };
1911
1912 static int ide_tape_probe(ide_drive_t *drive)
1913 {
1914         idetape_tape_t *tape;
1915         struct gendisk *g;
1916         int minor;
1917
1918         ide_debug_log(IDE_DBG_FUNC, "enter");
1919
1920         if (!strstr(DRV_NAME, drive->driver_req))
1921                 goto failed;
1922
1923         if (drive->media != ide_tape)
1924                 goto failed;
1925
1926         if ((drive->dev_flags & IDE_DFLAG_ID_READ) &&
1927             ide_check_atapi_device(drive, DRV_NAME) == 0) {
1928                 printk(KERN_ERR "ide-tape: %s: not supported by this version of"
1929                                 " the driver\n", drive->name);
1930                 goto failed;
1931         }
1932         tape = kzalloc(sizeof(idetape_tape_t), GFP_KERNEL);
1933         if (tape == NULL) {
1934                 printk(KERN_ERR "ide-tape: %s: Can't allocate a tape struct\n",
1935                                 drive->name);
1936                 goto failed;
1937         }
1938
1939         g = alloc_disk(1 << PARTN_BITS);
1940         if (!g)
1941                 goto out_free_tape;
1942
1943         ide_init_disk(g, drive);
1944
1945         tape->dev.parent = &drive->gendev;
1946         tape->dev.release = ide_tape_release;
1947         dev_set_name(&tape->dev, dev_name(&drive->gendev));
1948
1949         if (device_register(&tape->dev))
1950                 goto out_free_disk;
1951
1952         tape->drive = drive;
1953         tape->driver = &idetape_driver;
1954         tape->disk = g;
1955
1956         g->private_data = &tape->driver;
1957
1958         drive->driver_data = tape;
1959
1960         mutex_lock(&idetape_ref_mutex);
1961         for (minor = 0; idetape_devs[minor]; minor++)
1962                 ;
1963         idetape_devs[minor] = tape;
1964         mutex_unlock(&idetape_ref_mutex);
1965
1966         idetape_setup(drive, tape, minor);
1967
1968         device_create(idetape_sysfs_class, &drive->gendev,
1969                       MKDEV(IDETAPE_MAJOR, minor), NULL, "%s", tape->name);
1970         device_create(idetape_sysfs_class, &drive->gendev,
1971                       MKDEV(IDETAPE_MAJOR, minor + 128), NULL,
1972                       "n%s", tape->name);
1973
1974         g->fops = &idetape_block_ops;
1975         ide_register_region(g);
1976
1977         return 0;
1978
1979 out_free_disk:
1980         put_disk(g);
1981 out_free_tape:
1982         kfree(tape);
1983 failed:
1984         return -ENODEV;
1985 }
1986
1987 static void __exit idetape_exit(void)
1988 {
1989         driver_unregister(&idetape_driver.gen_driver);
1990         class_destroy(idetape_sysfs_class);
1991         unregister_chrdev(IDETAPE_MAJOR, "ht");
1992 }
1993
1994 static int __init idetape_init(void)
1995 {
1996         int error = 1;
1997         idetape_sysfs_class = class_create(THIS_MODULE, "ide_tape");
1998         if (IS_ERR(idetape_sysfs_class)) {
1999                 idetape_sysfs_class = NULL;
2000                 printk(KERN_ERR "Unable to create sysfs class for ide tapes\n");
2001                 error = -EBUSY;
2002                 goto out;
2003         }
2004
2005         if (register_chrdev(IDETAPE_MAJOR, "ht", &idetape_fops)) {
2006                 printk(KERN_ERR "ide-tape: Failed to register chrdev"
2007                                 " interface\n");
2008                 error = -EBUSY;
2009                 goto out_free_class;
2010         }
2011
2012         error = driver_register(&idetape_driver.gen_driver);
2013         if (error)
2014                 goto out_free_driver;
2015
2016         return 0;
2017
2018 out_free_driver:
2019         driver_unregister(&idetape_driver.gen_driver);
2020 out_free_class:
2021         class_destroy(idetape_sysfs_class);
2022 out:
2023         return error;
2024 }
2025
2026 MODULE_ALIAS("ide:*m-tape*");
2027 module_init(idetape_init);
2028 module_exit(idetape_exit);
2029 MODULE_ALIAS_CHARDEV_MAJOR(IDETAPE_MAJOR);
2030 MODULE_DESCRIPTION("ATAPI Streaming TAPE Driver");
2031 MODULE_LICENSE("GPL");