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ide: add ide_issue_pc() helper
[linux-2.6-block.git] / drivers / ide / ide-tape.c
CommitLineData
1da177e4 1/*
5ce78af4
BP		 2 * IDE ATAPI streaming tape driver.
3 *
59bca8cc
BZ		 4 * Copyright (C) 1995-1999 Gadi Oxman <gadio@netvision.net.il>
5 * Copyright (C) 2003-2005 Bartlomiej Zolnierkiewicz
1da177e4 6 *
1da177e4
LT		 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).
1da177e4 13 *
5ce78af4
BP		 14 * For a historical changelog see
15 * Documentation/ide/ChangeLog.ide-tape.1995-2002
1da177e4
LT		 16 */
17
dfe79936 18#define IDETAPE_VERSION "1.20"
1da177e4 19
1da177e4
LT		 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>
9bae1ff3 28#include <linux/jiffies.h>
1da177e4 29#include <linux/major.h>
1da177e4
LT		 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>
cf8b8975 38#include <linux/mutex.h>
90699ce2 39#include <scsi/scsi.h>
1da177e4
LT		 40
41#include <asm/byteorder.h>
c837cfa5
BP		 42#include <linux/irq.h>
43#include <linux/uaccess.h>
44#include <linux/io.h>
1da177e4 45#include <asm/unaligned.h>
1da177e4
LT		 46#include <linux/mtio.h>
47
8004a8c9
BP		 48enum {
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
1da177e4 74/**************************** Tunable parameters *****************************/
1da177e4 75/*
3c98bf34
BP		 76 * After each failed packet command we issue a request sense command and retry
77 * the packet command IDETAPE_MAX_PC_RETRIES times.
1da177e4 78 *
3c98bf34 79 * Setting IDETAPE_MAX_PC_RETRIES to 0 will disable retries.
1da177e4
LT		 80 */
81#define IDETAPE_MAX_PC_RETRIES 3
82
83/*
3c98bf34
BP		 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)
1da177e4
LT		 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/*
3c98bf34
BP		 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.
1da177e4 108 */
3c98bf34 109#define IDETAPE_FIFO_THRESHOLD 2
1da177e4
LT		 110
111/*
3c98bf34 112 * DSC polling parameters.
1da177e4 113 *
3c98bf34
BP		 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:
1da177e4 116 *
3c98bf34
BP		 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.
1da177e4 122 *
3c98bf34
BP		 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).
1da177e4 131 *
3c98bf34
BP		 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.
1da177e4 134 */
3c98bf34
BP		 135
136/* DSC timings. */
1da177e4
LT		 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
54abf37e
BP		 147/* tape directions */
148enum {
149 IDETAPE_DIR_NONE = (1 << 0),
150 IDETAPE_DIR_READ = (1 << 1),
151 IDETAPE_DIR_WRITE = (1 << 2),
152};
1da177e4
LT		 153
154struct idetape_bh {
ab057968 155 u32 b_size;
1da177e4
LT		 156 atomic_t b_count;
157 struct idetape_bh *b_reqnext;
158 char *b_data;
159};
160
03056b90
BP		 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
182enum {
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
346331f8
BP		 198/* Tape flag bits values. */
199enum {
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 */
42d54689 204 IDETAPE_FLAG_BUSY = (1 << 2),
346331f8 205 /* Attempt to auto-detect the current user block size */
42d54689 206 IDETAPE_FLAG_DETECT_BS = (1 << 3),
346331f8 207 /* Currently on a filemark */
42d54689 208 IDETAPE_FLAG_FILEMARK = (1 << 4),
346331f8 209 /* DRQ interrupt device */
42d54689 210 IDETAPE_FLAG_DRQ_INTERRUPT = (1 << 5),
346331f8 211 /* 0 = no tape is loaded, so we don't rewind after ejecting */
42d54689 212 IDETAPE_FLAG_MEDIUM_PRESENT = (1 << 6),
346331f8
BP		 213};
214
1da177e4 215/*
3c98bf34
BP		 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.
1da177e4
LT		 218 */
219typedef 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 */
d236d74c 241 struct ide_atapi_pc *pc;
1da177e4 242 /* Last failed packet command */
d236d74c 243 struct ide_atapi_pc *failed_pc;
1da177e4 244 /* Packet command stack */
d236d74c 245 struct ide_atapi_pc pc_stack[IDETAPE_PC_STACK];
1da177e4
LT		 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 /*
3c98bf34 253 * DSC polling variables.
1da177e4 254 *
3c98bf34
BP		 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
5bd50dc6 258 * data transfer) request in the device request queue.
1da177e4
LT		 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 */
54bb2074
BP		 266 unsigned long best_dsc_rw_freq;
267 unsigned long dsc_poll_freq;
1da177e4
LT		 268 unsigned long dsc_timeout;
269
3c98bf34 270 /* Read position information */
1da177e4
LT		 271 u8 partition;
272 /* Current block */
54bb2074 273 unsigned int first_frame;
1da177e4 274
3c98bf34 275 /* Last error information */
1da177e4
LT		 276 u8 sense_key, asc, ascq;
277
3c98bf34 278 /* Character device operation */
1da177e4
LT		 279 unsigned int minor;
280 /* device name */
281 char name[4];
282 /* Current character device data transfer direction */
54abf37e 283 u8 chrdev_dir;
1da177e4 284
54bb2074
BP		 285 /* tape block size, usually 512 or 1024 bytes */
286 unsigned short blk_size;
1da177e4 287 int user_bs_factor;
b6422013 288
1da177e4 289 /* Copy of the tape's Capabilities and Mechanical Page */
b6422013 290 u8 caps[20];
1da177e4
LT		 291
292 /*
3c98bf34 293 * Active data transfer request parameters.
1da177e4 294 *
3c98bf34
BP		 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.
1da177e4 298 */
83042b24 299
3c98bf34 300 /* Data buffer size chosen based on the tape's recommendation */
f73850a3 301 int buffer_size;
077e3bdb
BP		 302 /* merge buffer */
303 struct idetape_bh *merge_bh;
01a63aeb
BP		 304 /* size of the merge buffer */
305 int merge_bh_size;
077e3bdb 306 /* pointer to current buffer head within the merge buffer */
1da177e4
LT		 307 struct idetape_bh *bh;
308 char *b_data;
309 int b_count;
3c98bf34 310
a997a435 311 int pages_per_buffer;
1da177e4
LT		 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 */
54bb2074 318 spinlock_t lock;
1da177e4 319
3c98bf34 320 /* Measures average tape speed */
1da177e4
LT		 321 unsigned long avg_time;
322 int avg_size;
323 int avg_speed;
324
1da177e4
LT		 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
8004a8c9 332 u32 debug_mask;
1da177e4
LT		 333} idetape_tape_t;
334
cf8b8975 335static DEFINE_MUTEX(idetape_ref_mutex);
1da177e4 336
d5dee80a
WD		 337static struct class *idetape_sysfs_class;
338
1da177e4
LT		 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
344static struct ide_tape_obj *ide_tape_get(struct gendisk *disk)
345{
346 struct ide_tape_obj *tape = NULL;
347
cf8b8975 348 mutex_lock(&idetape_ref_mutex);
1da177e4
LT		 349 tape = ide_tape_g(disk);
350 if (tape)
351 kref_get(&tape->kref);
cf8b8975 352 mutex_unlock(&idetape_ref_mutex);
1da177e4
LT		 353 return tape;
354}
355
356static void ide_tape_release(struct kref *);
357
358static void ide_tape_put(struct ide_tape_obj *tape)
359{
cf8b8975 360 mutex_lock(&idetape_ref_mutex);
1da177e4 361 kref_put(&tape->kref, ide_tape_release);
cf8b8975 362 mutex_unlock(&idetape_ref_mutex);
1da177e4
LT		 363}
364
1da177e4 365/*
3c98bf34
BP		 366 * The variables below are used for the character device interface. Additional
367 * state variables are defined in our ide_drive_t structure.
1da177e4 368 */
5a04cfa9 369static struct ide_tape_obj *idetape_devs[MAX_HWIFS * MAX_DRIVES];
1da177e4
LT		 370
371#define ide_tape_f(file) ((file)->private_data)
372
373static struct ide_tape_obj *ide_tape_chrdev_get(unsigned int i)
374{
375 struct ide_tape_obj *tape = NULL;
376
cf8b8975 377 mutex_lock(&idetape_ref_mutex);
1da177e4
LT		 378 tape = idetape_devs[i];
379 if (tape)
380 kref_get(&tape->kref);
cf8b8975 381 mutex_unlock(&idetape_ref_mutex);
1da177e4
LT		 382 return tape;
383}
384
d236d74c 385static void idetape_input_buffers(ide_drive_t *drive, struct ide_atapi_pc *pc,
5a04cfa9 386 unsigned int bcount)
1da177e4
LT		 387{
388 struct idetape_bh *bh = pc->bh;
389 int count;
390
391 while (bcount) {
1da177e4
LT		 392 if (bh == NULL) {
393 printk(KERN_ERR "ide-tape: bh == NULL in "
394 "idetape_input_buffers\n");
9f87abe8 395 ide_pad_transfer(drive, 0, bcount);
1da177e4
LT		 396 return;
397 }
5a04cfa9
BP		 398 count = min(
399 (unsigned int)(bh->b_size - atomic_read(&bh->b_count)),
400 bcount);
9567b349 401 drive->hwif->input_data(drive, NULL, bh->b_data +
5a04cfa9 402 atomic_read(&bh->b_count), count);
1da177e4
LT		 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
d236d74c 414static void idetape_output_buffers(ide_drive_t *drive, struct ide_atapi_pc *pc,
5a04cfa9 415 unsigned int bcount)
1da177e4
LT		 416{
417 struct idetape_bh *bh = pc->bh;
418 int count;
419
420 while (bcount) {
1da177e4 421 if (bh == NULL) {
5a04cfa9
BP		 422 printk(KERN_ERR "ide-tape: bh == NULL in %s\n",
423 __func__);
1da177e4
LT		 424 return;
425 }
1da177e4 426 count = min((unsigned int)pc->b_count, (unsigned int)bcount);
9567b349 427 drive->hwif->output_data(drive, NULL, pc->b_data, count);
1da177e4
LT		 428 bcount -= count;
429 pc->b_data += count;
430 pc->b_count -= count;
431 if (!pc->b_count) {
5a04cfa9
BP		 432 bh = bh->b_reqnext;
433 pc->bh = bh;
1da177e4
LT		 434 if (bh) {
435 pc->b_data = bh->b_data;
436 pc->b_count = atomic_read(&bh->b_count);
437 }
438 }
439 }
440}
441
d236d74c 442static void idetape_update_buffers(struct ide_atapi_pc *pc)
1da177e4
LT		 443{
444 struct idetape_bh *bh = pc->bh;
445 int count;
d236d74c 446 unsigned int bcount = pc->xferred;
1da177e4 447
346331f8 448 if (pc->flags & PC_FLAG_WRITING)
1da177e4
LT		 449 return;
450 while (bcount) {
1da177e4 451 if (bh == NULL) {
5a04cfa9
BP		 452 printk(KERN_ERR "ide-tape: bh == NULL in %s\n",
453 __func__);
1da177e4
LT		 454 return;
455 }
1da177e4
LT		 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 */
d236d74c 471static struct ide_atapi_pc *idetape_next_pc_storage(ide_drive_t *drive)
1da177e4
LT		 472{
473 idetape_tape_t *tape = drive->driver_data;
474
8004a8c9
BP		 475 debug_log(DBG_PCRQ_STACK, "pc_stack_index=%d\n", tape->pc_stack_index);
476
1da177e4 477 if (tape->pc_stack_index == IDETAPE_PC_STACK)
5a04cfa9 478 tape->pc_stack_index = 0;
1da177e4
LT		 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 */
5a04cfa9 487
1da177e4
LT		 488/**************************************************************
489 * *
490 * This should get fixed to use kmalloc(.., GFP_ATOMIC) *
491 * followed later on by kfree(). -ml *
492 * *
493 **************************************************************/
5a04cfa9
BP		 494
495static struct request *idetape_next_rq_storage(ide_drive_t *drive)
1da177e4
LT		 496{
497 idetape_tape_t *tape = drive->driver_data;
498
8004a8c9
BP		 499 debug_log(DBG_PCRQ_STACK, "rq_stack_index=%d\n", tape->rq_stack_index);
500
1da177e4 501 if (tape->rq_stack_index == IDETAPE_PC_STACK)
5a04cfa9 502 tape->rq_stack_index = 0;
1da177e4
LT		 503 return (&tape->rq_stack[tape->rq_stack_index++]);
504}
505
1da177e4 506/*
1b5db434
BP		 507 * called on each failed packet command retry to analyze the request sense. We
508 * currently do not utilize this information.
1da177e4 509 */
1b5db434 510static void idetape_analyze_error(ide_drive_t *drive, u8 *sense)
1da177e4
LT		 511{
512 idetape_tape_t *tape = drive->driver_data;
d236d74c 513 struct ide_atapi_pc *pc = tape->failed_pc;
1da177e4 514
1b5db434
BP		 515 tape->sense_key = sense[2] & 0xF;
516 tape->asc = sense[12];
517 tape->ascq = sense[13];
8004a8c9
BP		 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);
1da177e4 521
d236d74c 522 /* Correct pc->xferred by asking the tape. */
346331f8 523 if (pc->flags & PC_FLAG_DMA_ERROR) {
d236d74c 524 pc->xferred = pc->req_xfer -
54bb2074 525 tape->blk_size *
5d0cc8ae 526 get_unaligned_be32(&sense[3]);
1da177e4
LT		 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 */
90699ce2 535 if ((pc->c[0] == READ_6 || pc->c[0] == WRITE_6)
1b5db434
BP		 536 /* length == 0 */
537 && pc->c[4] == 0 && pc->c[3] == 0 && pc->c[2] == 0) {
538 if (tape->sense_key == 5) {
1da177e4
LT		 539 /* don't report an error, everything's ok */
540 pc->error = 0;
541 /* don't retry read/write */
346331f8 542 pc->flags |= PC_FLAG_ABORT;
1da177e4
LT		 543 }
544 }
90699ce2 545 if (pc->c[0] == READ_6 && (sense[2] & 0x80)) {
1da177e4 546 pc->error = IDETAPE_ERROR_FILEMARK;
346331f8 547 pc->flags |= PC_FLAG_ABORT;
1da177e4 548 }
90699ce2 549 if (pc->c[0] == WRITE_6) {
1b5db434
BP		 550 if ((sense[2] & 0x40) || (tape->sense_key == 0xd
551 && tape->asc == 0x0 && tape->ascq == 0x2)) {
1da177e4 552 pc->error = IDETAPE_ERROR_EOD;
346331f8 553 pc->flags |= PC_FLAG_ABORT;
1da177e4
LT		 554 }
555 }
90699ce2 556 if (pc->c[0] == READ_6 || pc->c[0] == WRITE_6) {
1b5db434 557 if (tape->sense_key == 8) {
1da177e4 558 pc->error = IDETAPE_ERROR_EOD;
346331f8 559 pc->flags |= PC_FLAG_ABORT;
1da177e4 560 }
346331f8 561 if (!(pc->flags & PC_FLAG_ABORT) &&
d236d74c 562 pc->xferred)
1da177e4
LT		 563 pc->retries = IDETAPE_MAX_PC_RETRIES + 1;
564 }
565}
566
d01dbc3b 567/* Free data buffers completely. */
077e3bdb 568static void ide_tape_kfree_buffer(idetape_tape_t *tape)
1da177e4 569{
077e3bdb 570 struct idetape_bh *prev_bh, *bh = tape->merge_bh;
d01dbc3b
BP		 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;
1da177e4
LT		 583 }
584 prev_bh = bh;
585 bh = bh->b_reqnext;
586 kfree(prev_bh);
587 }
077e3bdb 588 kfree(tape->merge_bh);
1da177e4
LT		 589}
590
1da177e4
LT		 591static 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;
1da177e4 597
8004a8c9 598 debug_log(DBG_PROCS, "Enter %s\n", __func__);
1da177e4
LT		 599
600 switch (uptodate) {
5a04cfa9
BP		 601 case 0: error = IDETAPE_ERROR_GENERAL; break;
602 case 1: error = 0; break;
603 default: error = uptodate;
1da177e4
LT		 604 }
605 rq->errors = error;
606 if (error)
607 tape->failed_pc = NULL;
608
3687221f
BZ		 609 if (!blk_special_request(rq)) {
610 ide_end_request(drive, uptodate, nr_sects);
611 return 0;
612 }
613
54bb2074 614 spin_lock_irqsave(&tape->lock, flags);
1da177e4 615
1da177e4 616 ide_end_drive_cmd(drive, 0, 0);
1da177e4 617
54bb2074 618 spin_unlock_irqrestore(&tape->lock, flags);
1da177e4
LT		 619 return 0;
620}
621
92f5daff 622static void ide_tape_callback(ide_drive_t *drive)
1da177e4
LT		 623{
624 idetape_tape_t *tape = drive->driver_data;
5985e6ab
BZ		 625 struct ide_atapi_pc *pc = tape->pc;
626 int uptodate = pc->error ? 0 : 1;
1da177e4 627
8004a8c9
BP		 628 debug_log(DBG_PROCS, "Enter %s\n", __func__);
629
5985e6ab
BZ		 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 }
1da177e4 675 }
5985e6ab
BZ		 676
677 idetape_end_request(drive, uptodate, 0);
1da177e4
LT		 678}
679
5985e6ab
BZ		 680static 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;
1b06e92a 690 pc->callback = ide_tape_callback;
5985e6ab
BZ		 691}
692
d236d74c 693static void idetape_create_request_sense_cmd(struct ide_atapi_pc *pc)
1da177e4 694{
5a04cfa9 695 idetape_init_pc(pc);
90699ce2 696 pc->c[0] = REQUEST_SENSE;
1da177e4 697 pc->c[4] = 20;
d236d74c 698 pc->req_xfer = 20;
1da177e4
LT		 699}
700
701static void idetape_init_rq(struct request *rq, u8 cmd)
702{
e7b241a7 703 blk_rq_init(NULL, rq);
4aff5e23 704 rq->cmd_type = REQ_TYPE_SPECIAL;
1da177e4
LT		 705 rq->cmd[0] = cmd;
706}
707
708/*
3c98bf34
BP		 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.
1da177e4 714 *
3c98bf34
BP		 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.
1da177e4 718 *
3c98bf34
BP		 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.
1da177e4 722 */
d236d74c 723static void idetape_queue_pc_head(ide_drive_t *drive, struct ide_atapi_pc *pc,
5a04cfa9 724 struct request *rq)
1da177e4
LT		 725{
726 struct ide_tape_obj *tape = drive->driver_data;
727
728 idetape_init_rq(rq, REQ_IDETAPE_PC1);
e8a96aa7 729 rq->cmd_flags |= REQ_PREEMPT;
1da177e4
LT		 730 rq->buffer = (char *) pc;
731 rq->rq_disk = tape->disk;
63f5abb0 732 ide_do_drive_cmd(drive, rq);
1da177e4
LT		 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 */
258ec411 740static void idetape_retry_pc(ide_drive_t *drive)
1da177e4
LT		 741{
742 idetape_tape_t *tape = drive->driver_data;
d236d74c 743 struct ide_atapi_pc *pc;
1da177e4 744 struct request *rq;
1da177e4 745
64a57fe4 746 (void)ide_read_error(drive);
1da177e4
LT		 747 pc = idetape_next_pc_storage(drive);
748 rq = idetape_next_rq_storage(drive);
749 idetape_create_request_sense_cmd(pc);
346331f8 750 set_bit(IDETAPE_FLAG_IGNORE_DSC, &tape->flags);
1da177e4 751 idetape_queue_pc_head(drive, pc, rq);
1da177e4
LT		 752}
753
754/*
3c98bf34
BP		 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.
1da177e4 757 */
5a04cfa9 758static void idetape_postpone_request(ide_drive_t *drive)
1da177e4
LT		 759{
760 idetape_tape_t *tape = drive->driver_data;
761
8004a8c9
BP		 762 debug_log(DBG_PROCS, "Enter %s\n", __func__);
763
1da177e4 764 tape->postponed_rq = HWGROUP(drive)->rq;
54bb2074 765 ide_stall_queue(drive, tape->dsc_poll_freq);
1da177e4
LT		 766}
767
d236d74c 768typedef void idetape_io_buf(ide_drive_t *, struct ide_atapi_pc *, unsigned int);
a1efc85f 769
1da177e4 770/*
a1efc85f
BP		 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
8d06bfad 775 * idetape_issue_pc.
1da177e4 776 */
a1efc85f 777static ide_startstop_t idetape_pc_intr(ide_drive_t *drive)
1da177e4
LT		 778{
779 ide_hwif_t *hwif = drive->hwif;
780 idetape_tape_t *tape = drive->driver_data;
d236d74c 781 struct ide_atapi_pc *pc = tape->pc;
a1efc85f
BP		 782 xfer_func_t *xferfunc;
783 idetape_io_buf *iobuf;
1da177e4 784 unsigned int temp;
790d1239 785 u16 bcount;
8e7657ae 786 u8 stat, ireason;
1da177e4 787
8004a8c9 788 debug_log(DBG_PROCS, "Enter %s - interrupt handler\n", __func__);
1da177e4
LT		 789
790 /* Clear the interrupt */
c47137a9 791 stat = ide_read_status(drive);
1da177e4 792
346331f8 793 if (pc->flags & PC_FLAG_DMA_IN_PROGRESS) {
5e37bdc0 794 if (hwif->dma_ops->dma_end(drive) || (stat & ERR_STAT)) {
346331f8 795 pc->flags |= PC_FLAG_DMA_ERROR;
1da177e4 796 } else {
d236d74c 797 pc->xferred = pc->req_xfer;
1da177e4
LT		 798 idetape_update_buffers(pc);
799 }
8004a8c9
BP		 800 debug_log(DBG_PROCS, "DMA finished\n");
801
1da177e4
LT		 802 }
803
804 /* No more interrupts */
22c525b9 805 if ((stat & DRQ_STAT) == 0) {
8004a8c9 806 debug_log(DBG_SENSE, "Packet command completed, %d bytes"
d236d74c 807 " transferred\n", pc->xferred);
1da177e4 808
346331f8 809 pc->flags &= ~PC_FLAG_DMA_IN_PROGRESS;
87429bdc 810 local_irq_enable_in_hardirq();
1da177e4 811
90699ce2 812 if ((stat & ERR_STAT) && pc->c[0] == REQUEST_SENSE)
22c525b9 813 stat &= ~ERR_STAT;
346331f8 814 if ((stat & ERR_STAT) || (pc->flags & PC_FLAG_DMA_ERROR)) {
22c525b9 815 /* Error detected */
8004a8c9
BP		 816 debug_log(DBG_ERR, "%s: I/O error\n", tape->name);
817
90699ce2 818 if (pc->c[0] == REQUEST_SENSE) {
568ca927
BZ		 819 printk(KERN_ERR "%s: I/O error in request sense"
820 " command\n", drive->name);
1da177e4
LT		 821 return ide_do_reset(drive);
822 }
8004a8c9
BP		 823 debug_log(DBG_ERR, "[cmd %x]: check condition\n",
824 pc->c[0]);
825
1da177e4 826 /* Retry operation */
258ec411
BZ		 827 idetape_retry_pc(drive);
828 return ide_stopped;
1da177e4
LT		 829 }
830 pc->error = 0;
346331f8 831 if ((pc->flags & PC_FLAG_WAIT_FOR_DSC) &&
22c525b9 832 (stat & SEEK_STAT) == 0) {
1da177e4
LT		 833 /* Media access command */
834 tape->dsc_polling_start = jiffies;
54bb2074 835 tape->dsc_poll_freq = IDETAPE_DSC_MA_FAST;
1da177e4
LT		 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 */
1b06e92a 844 pc->callback(drive);
92f5daff 845 return ide_stopped;
1da177e4 846 }
346331f8
BP		 847
848 if (pc->flags & PC_FLAG_DMA_IN_PROGRESS) {
849 pc->flags &= ~PC_FLAG_DMA_IN_PROGRESS;
568ca927
BZ		 850 printk(KERN_ERR "%s: The device wants to issue more interrupts "
851 "in DMA mode\n", drive->name);
7469aaf6 852 ide_dma_off(drive);
1da177e4
LT		 853 return ide_do_reset(drive);
854 }
855 /* Get the number of bytes to transfer on this interrupt. */
4c3032d8
BZ		 856 bcount = (hwif->INB(hwif->io_ports.lbah_addr) << 8) |
857 hwif->INB(hwif->io_ports.lbam_addr);
1da177e4 858
4c3032d8 859 ireason = hwif->INB(hwif->io_ports.nsect_addr);
1da177e4 860
8e7657ae 861 if (ireason & CD) {
568ca927 862 printk(KERN_ERR "%s: CoD != 0 in %s\n", drive->name, __func__);
1da177e4
LT		 863 return ide_do_reset(drive);
864 }
346331f8 865 if (((ireason & IO) == IO) == !!(pc->flags & PC_FLAG_WRITING)) {
1da177e4 866 /* Hopefully, we will never get here */
568ca927
BZ		 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",
8e7657ae 870 (ireason & IO) ? "Read" : "Write");
1da177e4
LT		 871 return ide_do_reset(drive);
872 }
346331f8 873 if (!(pc->flags & PC_FLAG_WRITING)) {
1da177e4 874 /* Reading - Check that we have enough space */
d236d74c
BP		 875 temp = pc->xferred + bcount;
876 if (temp > pc->req_xfer) {
877 if (temp > pc->buf_size) {
568ca927
BZ		 878 printk(KERN_ERR "%s: The device wants to send "
879 "us more data than expected - "
880 "discarding data\n",
881 drive->name);
9f87abe8 882 ide_pad_transfer(drive, 0, bcount);
a1efc85f
BP		 883 ide_set_handler(drive, &idetape_pc_intr,
884 IDETAPE_WAIT_CMD, NULL);
1da177e4
LT		 885 return ide_started;
886 }
568ca927 887 debug_log(DBG_SENSE, "The device wants to send us more "
8004a8c9 888 "data than expected - allowing transfer\n");
1da177e4 889 }
a1efc85f 890 iobuf = &idetape_input_buffers;
9567b349 891 xferfunc = hwif->input_data;
1da177e4 892 } else {
a1efc85f 893 iobuf = &idetape_output_buffers;
9567b349 894 xferfunc = hwif->output_data;
1da177e4 895 }
a1efc85f
BP		 896
897 if (pc->bh)
898 iobuf(drive, pc, bcount);
899 else
9567b349 900 xferfunc(drive, NULL, pc->cur_pos, bcount);
a1efc85f 901
1da177e4 902 /* Update the current position */
d236d74c
BP		 903 pc->xferred += bcount;
904 pc->cur_pos += bcount;
8004a8c9
BP		 905
906 debug_log(DBG_SENSE, "[cmd %x] transferred %d bytes on that intr.\n",
907 pc->c[0], bcount);
908
1da177e4
LT		 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/*
3c98bf34 915 * Packet Command Interface
1da177e4 916 *
3c98bf34
BP		 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.
1da177e4 920 *
3c98bf34 921 * The handling will be done in three stages:
1da177e4 922 *
3c98bf34
BP		 923 * 1. idetape_issue_pc will send the packet command to the drive, and will set
924 * the interrupt handler to idetape_pc_intr.
1da177e4 925 *
3c98bf34
BP		 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.
1da177e4 928 *
3c98bf34
BP		 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.
1da177e4 936 *
3c98bf34
BP		 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.
1da177e4 939 *
3c98bf34 940 * 4. When the packet command is finished, it will be checked for errors.
1da177e4 941 *
3c98bf34
BP		 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.
1da177e4 945 *
3c98bf34
BP		 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.
1da177e4 949 */
5a7b75ab
BZ		 950static ide_startstop_t idetape_transfer_pc(ide_drive_t *drive)
951{
5a7b75ab 952 idetape_tape_t *tape = drive->driver_data;
5a7b75ab 953
594c16d8
BZ		 954 return ide_transfer_pc(drive, tape->pc, idetape_pc_intr,
955 IDETAPE_WAIT_CMD, NULL);
1da177e4
LT		 956}
957
d236d74c
BP		 958static ide_startstop_t idetape_issue_pc(ide_drive_t *drive,
959 struct ide_atapi_pc *pc)
1da177e4 960{
1da177e4 961 idetape_tape_t *tape = drive->driver_data;
1da177e4 962
90699ce2
BP		 963 if (tape->pc->c[0] == REQUEST_SENSE &&
964 pc->c[0] == REQUEST_SENSE) {
1da177e4
LT		 965 printk(KERN_ERR "ide-tape: possible ide-tape.c bug - "
966 "Two request sense in serial were issued\n");
967 }
1da177e4 968
90699ce2 969 if (tape->failed_pc == NULL && pc->c[0] != REQUEST_SENSE)
1da177e4
LT		 970 tape->failed_pc = pc;
971 /* Set the current packet command */
972 tape->pc = pc;
973
974 if (pc->retries > IDETAPE_MAX_PC_RETRIES ||
346331f8 975 (pc->flags & PC_FLAG_ABORT)) {
1da177e4 976 /*
3c98bf34
BP		 977 * We will "abort" retrying a packet command in case legitimate
978 * error code was received (crossing a filemark, or end of the
979 * media, for example).
1da177e4 980 */
346331f8 981 if (!(pc->flags & PC_FLAG_ABORT)) {
90699ce2 982 if (!(pc->c[0] == TEST_UNIT_READY &&
1da177e4
LT		 983 tape->sense_key == 2 && tape->asc == 4 &&
984 (tape->ascq == 1 || tape->ascq == 8))) {
985 printk(KERN_ERR "ide-tape: %s: I/O error, "
986 "pc = %2x, key = %2x, "
987 "asc = %2x, ascq = %2x\n",
988 tape->name, pc->c[0],
989 tape->sense_key, tape->asc,
990 tape->ascq);
991 }
992 /* Giving up */
993 pc->error = IDETAPE_ERROR_GENERAL;
994 }
995 tape->failed_pc = NULL;
1b06e92a 996 pc->callback(drive);
92f5daff 997 return ide_stopped;
1da177e4 998 }
8004a8c9 999 debug_log(DBG_SENSE, "Retry #%d, cmd = %02X\n", pc->retries, pc->c[0]);
1da177e4
LT		 1000
1001 pc->retries++;
2fc57388 1002
6bf1641c
BZ		 1003 return ide_issue_pc(drive, pc, idetape_transfer_pc,
1004 IDETAPE_WAIT_CMD, NULL);
1da177e4
LT		 1005}
1006
3c98bf34 1007/* A mode sense command is used to "sense" tape parameters. */
d236d74c 1008static void idetape_create_mode_sense_cmd(struct ide_atapi_pc *pc, u8 page_code)
1da177e4
LT		 1009{
1010 idetape_init_pc(pc);
90699ce2 1011 pc->c[0] = MODE_SENSE;
1da177e4 1012 if (page_code != IDETAPE_BLOCK_DESCRIPTOR)
3c98bf34
BP		 1013 /* DBD = 1 - Don't return block descriptors */
1014 pc->c[1] = 8;
1da177e4
LT		 1015 pc->c[2] = page_code;
1016 /*
1017 * Changed pc->c[3] to 0 (255 will at best return unused info).
1018 *
1019 * For SCSI this byte is defined as subpage instead of high byte
1020 * of length and some IDE drives seem to interpret it this way
1021 * and return an error when 255 is used.
1022 */
1023 pc->c[3] = 0;
3c98bf34
BP		 1024 /* We will just discard data in that case */
1025 pc->c[4] = 255;
1da177e4 1026 if (page_code == IDETAPE_BLOCK_DESCRIPTOR)
d236d74c 1027 pc->req_xfer = 12;
1da177e4 1028 else if (page_code == IDETAPE_CAPABILITIES_PAGE)
d236d74c 1029 pc->req_xfer = 24;
1da177e4 1030 else
d236d74c 1031 pc->req_xfer = 50;
1da177e4
LT		 1032}
1033
5a04cfa9 1034static ide_startstop_t idetape_media_access_finished(ide_drive_t *drive)
1da177e4
LT		 1035{
1036 idetape_tape_t *tape = drive->driver_data;
d236d74c 1037 struct ide_atapi_pc *pc = tape->pc;
22c525b9 1038 u8 stat;
1da177e4 1039
c47137a9
BZ		 1040 stat = ide_read_status(drive);
1041
22c525b9
BZ		 1042 if (stat & SEEK_STAT) {
1043 if (stat & ERR_STAT) {
1da177e4 1044 /* Error detected */
90699ce2 1045 if (pc->c[0] != TEST_UNIT_READY)
1da177e4
LT		 1046 printk(KERN_ERR "ide-tape: %s: I/O error, ",
1047 tape->name);
1048 /* Retry operation */
258ec411
BZ		 1049 idetape_retry_pc(drive);
1050 return ide_stopped;
1da177e4
LT		 1051 }
1052 pc->error = 0;
1053 if (tape->failed_pc == pc)
1054 tape->failed_pc = NULL;
1055 } else {
1056 pc->error = IDETAPE_ERROR_GENERAL;
1057 tape->failed_pc = NULL;
1058 }
1b06e92a 1059 pc->callback(drive);
92f5daff 1060 return ide_stopped;
1da177e4
LT		 1061}
1062
d236d74c
BP		 1063static void idetape_create_read_cmd(idetape_tape_t *tape,
1064 struct ide_atapi_pc *pc,
5a04cfa9 1065 unsigned int length, struct idetape_bh *bh)
1da177e4
LT		 1066{
1067 idetape_init_pc(pc);
90699ce2 1068 pc->c[0] = READ_6;
860ff5ec 1069 put_unaligned(cpu_to_be32(length), (unsigned int *) &pc->c[1]);
1da177e4 1070 pc->c[1] = 1;
1da177e4
LT		 1071 pc->bh = bh;
1072 atomic_set(&bh->b_count, 0);
d236d74c
BP		 1073 pc->buf = NULL;
1074 pc->buf_size = length * tape->blk_size;
1075 pc->req_xfer = pc->buf_size;
f73850a3 1076 if (pc->req_xfer == tape->buffer_size)
5e331095 1077 pc->flags |= PC_FLAG_DMA_OK;
1da177e4
LT		 1078}
1079
d236d74c
BP		 1080static void idetape_create_write_cmd(idetape_tape_t *tape,
1081 struct ide_atapi_pc *pc,
5a04cfa9 1082 unsigned int length, struct idetape_bh *bh)
1da177e4
LT		 1083{
1084 idetape_init_pc(pc);
90699ce2 1085 pc->c[0] = WRITE_6;
860ff5ec 1086 put_unaligned(cpu_to_be32(length), (unsigned int *) &pc->c[1]);
1da177e4 1087 pc->c[1] = 1;
346331f8 1088 pc->flags |= PC_FLAG_WRITING;
1da177e4
LT		 1089 pc->bh = bh;
1090 pc->b_data = bh->b_data;
1091 pc->b_count = atomic_read(&bh->b_count);
d236d74c
BP		 1092 pc->buf = NULL;
1093 pc->buf_size = length * tape->blk_size;
1094 pc->req_xfer = pc->buf_size;
f73850a3 1095 if (pc->req_xfer == tape->buffer_size)
5e331095 1096 pc->flags |= PC_FLAG_DMA_OK;
1da177e4
LT		 1097}
1098
1da177e4
LT		 1099static ide_startstop_t idetape_do_request(ide_drive_t *drive,
1100 struct request *rq, sector_t block)
1101{
1102 idetape_tape_t *tape = drive->driver_data;
d236d74c 1103 struct ide_atapi_pc *pc = NULL;
1da177e4 1104 struct request *postponed_rq = tape->postponed_rq;
22c525b9 1105 u8 stat;
1da177e4 1106
8004a8c9
BP		 1107 debug_log(DBG_SENSE, "sector: %ld, nr_sectors: %ld,"
1108 " current_nr_sectors: %d\n",
1da177e4 1109 rq->sector, rq->nr_sectors, rq->current_nr_sectors);
1da177e4 1110
4aff5e23 1111 if (!blk_special_request(rq)) {
3c98bf34 1112 /* We do not support buffer cache originated requests. */
1da177e4 1113 printk(KERN_NOTICE "ide-tape: %s: Unsupported request in "
4aff5e23 1114 "request queue (%d)\n", drive->name, rq->cmd_type);
1da177e4
LT		 1115 ide_end_request(drive, 0, 0);
1116 return ide_stopped;
1117 }
1118
3c98bf34 1119 /* Retry a failed packet command */
28c7214b
BZ		 1120 if (tape->failed_pc && tape->pc->c[0] == REQUEST_SENSE) {
1121 pc = tape->failed_pc;
1122 goto out;
1123 }
5a04cfa9 1124
1da177e4
LT		 1125 if (postponed_rq != NULL)
1126 if (rq != postponed_rq) {
1127 printk(KERN_ERR "ide-tape: ide-tape.c bug - "
1128 "Two DSC requests were queued\n");
1129 idetape_end_request(drive, 0, 0);
1130 return ide_stopped;
1131 }
1da177e4
LT		 1132
1133 tape->postponed_rq = NULL;
1134
1135 /*
1136 * If the tape is still busy, postpone our request and service
1137 * the other device meanwhile.
1138 */
c47137a9 1139 stat = ide_read_status(drive);
1da177e4
LT		 1140
1141 if (!drive->dsc_overlap && !(rq->cmd[0] & REQ_IDETAPE_PC2))
346331f8 1142 set_bit(IDETAPE_FLAG_IGNORE_DSC, &tape->flags);
1da177e4
LT		 1143
1144 if (drive->post_reset == 1) {
346331f8 1145 set_bit(IDETAPE_FLAG_IGNORE_DSC, &tape->flags);
1da177e4
LT		 1146 drive->post_reset = 0;
1147 }
1148
346331f8 1149 if (!test_and_clear_bit(IDETAPE_FLAG_IGNORE_DSC, &tape->flags) &&
22c525b9 1150 (stat & SEEK_STAT) == 0) {
1da177e4
LT		 1151 if (postponed_rq == NULL) {
1152 tape->dsc_polling_start = jiffies;
54bb2074 1153 tape->dsc_poll_freq = tape->best_dsc_rw_freq;
1da177e4
LT		 1154 tape->dsc_timeout = jiffies + IDETAPE_DSC_RW_TIMEOUT;
1155 } else if (time_after(jiffies, tape->dsc_timeout)) {
1156 printk(KERN_ERR "ide-tape: %s: DSC timeout\n",
1157 tape->name);
1158 if (rq->cmd[0] & REQ_IDETAPE_PC2) {
1159 idetape_media_access_finished(drive);
1160 return ide_stopped;
1161 } else {
1162 return ide_do_reset(drive);
1163 }
5a04cfa9
BP		 1164 } else if (time_after(jiffies,
1165 tape->dsc_polling_start +
1166 IDETAPE_DSC_MA_THRESHOLD))
54bb2074 1167 tape->dsc_poll_freq = IDETAPE_DSC_MA_SLOW;
1da177e4
LT		 1168 idetape_postpone_request(drive);
1169 return ide_stopped;
1170 }
1171 if (rq->cmd[0] & REQ_IDETAPE_READ) {
1da177e4 1172 pc = idetape_next_pc_storage(drive);
5a04cfa9
BP		 1173 idetape_create_read_cmd(tape, pc, rq->current_nr_sectors,
1174 (struct idetape_bh *)rq->special);
1da177e4
LT		 1175 goto out;
1176 }
1177 if (rq->cmd[0] & REQ_IDETAPE_WRITE) {
1da177e4 1178 pc = idetape_next_pc_storage(drive);
5a04cfa9
BP		 1179 idetape_create_write_cmd(tape, pc, rq->current_nr_sectors,
1180 (struct idetape_bh *)rq->special);
1da177e4
LT		 1181 goto out;
1182 }
1da177e4 1183 if (rq->cmd[0] & REQ_IDETAPE_PC1) {
d236d74c 1184 pc = (struct ide_atapi_pc *) rq->buffer;
1da177e4
LT		 1185 rq->cmd[0] &= ~(REQ_IDETAPE_PC1);
1186 rq->cmd[0] |= REQ_IDETAPE_PC2;
1187 goto out;
1188 }
1189 if (rq->cmd[0] & REQ_IDETAPE_PC2) {
1190 idetape_media_access_finished(drive);
1191 return ide_stopped;
1192 }
1193 BUG();
1194out:
28c7214b
BZ		 1195 if (test_bit(IDETAPE_FLAG_DRQ_INTERRUPT, &tape->flags))
1196 pc->flags |= PC_FLAG_DRQ_INTERRUPT;
1197
8d06bfad 1198 return idetape_issue_pc(drive, pc);
1da177e4
LT		 1199}
1200
1da177e4 1201/*
41aa1706 1202 * The function below uses __get_free_pages to allocate a data buffer of size
f73850a3 1203 * tape->buffer_size (or a bit more). We attempt to combine sequential pages as
3c98bf34 1204 * much as possible.
1da177e4 1205 *
41aa1706
BP		 1206 * It returns a pointer to the newly allocated buffer, or NULL in case of
1207 * failure.
1da177e4 1208 */
077e3bdb
BP		 1209static struct idetape_bh *ide_tape_kmalloc_buffer(idetape_tape_t *tape,
1210 int full, int clear)
1da177e4 1211{
077e3bdb 1212 struct idetape_bh *prev_bh, *bh, *merge_bh;
a997a435 1213 int pages = tape->pages_per_buffer;
41aa1706 1214 unsigned int order, b_allocd;
1da177e4
LT		 1215 char *b_data = NULL;
1216
077e3bdb
BP		 1217 merge_bh = kmalloc(sizeof(struct idetape_bh), GFP_KERNEL);
1218 bh = merge_bh;
1da177e4
LT		 1219 if (bh == NULL)
1220 goto abort;
41aa1706
BP		 1221
1222 order = fls(pages) - 1;
1223 bh->b_data = (char *) __get_free_pages(GFP_KERNEL, order);
5a04cfa9 1224 if (!bh->b_data)
1da177e4 1225 goto abort;
41aa1706
BP		 1226 b_allocd = (1 << order) * PAGE_SIZE;
1227 pages &= (order-1);
1228
1da177e4 1229 if (clear)
41aa1706
BP		 1230 memset(bh->b_data, 0, b_allocd);
1231 bh->b_reqnext = NULL;
1232 bh->b_size = b_allocd;
1da177e4
LT		 1233 atomic_set(&bh->b_count, full ? bh->b_size : 0);
1234
41aa1706
BP		 1235 while (pages) {
1236 order = fls(pages) - 1;
1237 b_data = (char *) __get_free_pages(GFP_KERNEL, order);
5a04cfa9 1238 if (!b_data)
1da177e4 1239 goto abort;
41aa1706
BP		 1240 b_allocd = (1 << order) * PAGE_SIZE;
1241
1da177e4 1242 if (clear)
41aa1706
BP		 1243 memset(b_data, 0, b_allocd);
1244
1245 /* newly allocated page frames below buffer header or ...*/
1246 if (bh->b_data == b_data + b_allocd) {
1247 bh->b_size += b_allocd;
1248 bh->b_data -= b_allocd;
1da177e4 1249 if (full)
41aa1706 1250 atomic_add(b_allocd, &bh->b_count);
1da177e4
LT		 1251 continue;
1252 }
41aa1706 1253 /* they are above the header */
1da177e4 1254 if (b_data == bh->b_data + bh->b_size) {
41aa1706 1255 bh->b_size += b_allocd;
1da177e4 1256 if (full)
41aa1706 1257 atomic_add(b_allocd, &bh->b_count);
1da177e4
LT		 1258 continue;
1259 }
1260 prev_bh = bh;
5a04cfa9
BP		 1261 bh = kmalloc(sizeof(struct idetape_bh), GFP_KERNEL);
1262 if (!bh) {
41aa1706 1263 free_pages((unsigned long) b_data, order);
1da177e4
LT		 1264 goto abort;
1265 }
1266 bh->b_reqnext = NULL;
1267 bh->b_data = b_data;
41aa1706 1268 bh->b_size = b_allocd;
1da177e4
LT		 1269 atomic_set(&bh->b_count, full ? bh->b_size : 0);
1270 prev_bh->b_reqnext = bh;
41aa1706
BP		 1271
1272 pages &= (order-1);
1da177e4 1273 }
41aa1706 1274
1da177e4
LT		 1275 bh->b_size -= tape->excess_bh_size;
1276 if (full)
1277 atomic_sub(tape->excess_bh_size, &bh->b_count);
077e3bdb 1278 return merge_bh;
1da177e4 1279abort:
077e3bdb 1280 ide_tape_kfree_buffer(tape);
1da177e4
LT		 1281 return NULL;
1282}
1283
5a04cfa9 1284static int idetape_copy_stage_from_user(idetape_tape_t *tape,
8646c88f 1285 const char __user *buf, int n)
1da177e4
LT		 1286{
1287 struct idetape_bh *bh = tape->bh;
1288 int count;
dcd96379 1289 int ret = 0;
1da177e4
LT		 1290
1291 while (n) {
1da177e4 1292 if (bh == NULL) {
5a04cfa9
BP		 1293 printk(KERN_ERR "ide-tape: bh == NULL in %s\n",
1294 __func__);
dcd96379 1295 return 1;
1da177e4 1296 }
5a04cfa9
BP		 1297 count = min((unsigned int)
1298 (bh->b_size - atomic_read(&bh->b_count)),
1299 (unsigned int)n);
1300 if (copy_from_user(bh->b_data + atomic_read(&bh->b_count), buf,
1301 count))
dcd96379 1302 ret = 1;
1da177e4
LT		 1303 n -= count;
1304 atomic_add(count, &bh->b_count);
1305 buf += count;
1306 if (atomic_read(&bh->b_count) == bh->b_size) {
1307 bh = bh->b_reqnext;
1308 if (bh)
1309 atomic_set(&bh->b_count, 0);
1310 }
1311 }
1312 tape->bh = bh;
dcd96379 1313 return ret;
1da177e4
LT		 1314}
1315
5a04cfa9 1316static int idetape_copy_stage_to_user(idetape_tape_t *tape, char __user *buf,
99d74e61 1317 int n)
1da177e4
LT		 1318{
1319 struct idetape_bh *bh = tape->bh;
1320 int count;
dcd96379 1321 int ret = 0;
1da177e4
LT		 1322
1323 while (n) {
1da177e4 1324 if (bh == NULL) {
5a04cfa9
BP		 1325 printk(KERN_ERR "ide-tape: bh == NULL in %s\n",
1326 __func__);
dcd96379 1327 return 1;
1da177e4 1328 }
1da177e4 1329 count = min(tape->b_count, n);
dcd96379
DW		 1330 if (copy_to_user(buf, tape->b_data, count))
1331 ret = 1;
1da177e4
LT		 1332 n -= count;
1333 tape->b_data += count;
1334 tape->b_count -= count;
1335 buf += count;
1336 if (!tape->b_count) {
5a04cfa9
BP		 1337 bh = bh->b_reqnext;
1338 tape->bh = bh;
1da177e4
LT		 1339 if (bh) {
1340 tape->b_data = bh->b_data;
1341 tape->b_count = atomic_read(&bh->b_count);
1342 }
1343 }
1344 }
dcd96379 1345 return ret;
1da177e4
LT		 1346}
1347
077e3bdb 1348static void idetape_init_merge_buffer(idetape_tape_t *tape)
1da177e4 1349{
077e3bdb
BP		 1350 struct idetape_bh *bh = tape->merge_bh;
1351 tape->bh = tape->merge_bh;
5a04cfa9 1352
54abf37e 1353 if (tape->chrdev_dir == IDETAPE_DIR_WRITE)
1da177e4
LT		 1354 atomic_set(&bh->b_count, 0);
1355 else {
1356 tape->b_data = bh->b_data;
1357 tape->b_count = atomic_read(&bh->b_count);
1358 }
1359}
1360
1da177e4 1361/*
3c98bf34
BP		 1362 * Write a filemark if write_filemark=1. Flush the device buffers without
1363 * writing a filemark otherwise.
1da177e4 1364 */
5a04cfa9 1365static void idetape_create_write_filemark_cmd(ide_drive_t *drive,
d236d74c 1366 struct ide_atapi_pc *pc, int write_filemark)
1da177e4
LT		 1367{
1368 idetape_init_pc(pc);
90699ce2 1369 pc->c[0] = WRITE_FILEMARKS;
1da177e4 1370 pc->c[4] = write_filemark;
346331f8 1371 pc->flags |= PC_FLAG_WAIT_FOR_DSC;
1da177e4
LT		 1372}
1373
d236d74c 1374static void idetape_create_test_unit_ready_cmd(struct ide_atapi_pc *pc)
1da177e4
LT		 1375{
1376 idetape_init_pc(pc);
90699ce2 1377 pc->c[0] = TEST_UNIT_READY;
1da177e4
LT		 1378}
1379
1380/*
3c98bf34
BP		 1381 * We add a special packet command request to the tail of the request queue, and
1382 * wait for it to be serviced. This is not to be called from within the request
1383 * handling part of the driver! We allocate here data on the stack and it is
1384 * valid until the request is finished. This is not the case for the bottom part
1385 * of the driver, where we are always leaving the functions to wait for an
1386 * interrupt or a timer event.
1da177e4 1387 *
3c98bf34
BP		 1388 * From the bottom part of the driver, we should allocate safe memory using
1389 * idetape_next_pc_storage() and ide_tape_next_rq_storage(), and add the request
1390 * to the request list without waiting for it to be serviced! In that case, we
1391 * usually use idetape_queue_pc_head().
1da177e4 1392 */
ea1ab3d3 1393static int idetape_queue_pc_tail(ide_drive_t *drive, struct ide_atapi_pc *pc)
1da177e4
LT		 1394{
1395 struct ide_tape_obj *tape = drive->driver_data;
64ea1b4a
FT		 1396 struct request *rq;
1397 int error;
1da177e4 1398
64ea1b4a
FT		 1399 rq = blk_get_request(drive->queue, READ, __GFP_WAIT);
1400 rq->cmd_type = REQ_TYPE_SPECIAL;
1401 rq->cmd[0] = REQ_IDETAPE_PC1;
1402 rq->buffer = (char *)pc;
1403 error = blk_execute_rq(drive->queue, tape->disk, rq, 0);
1404 blk_put_request(rq);
1405 return error;
1da177e4
LT		 1406}
1407
d236d74c
BP		 1408static void idetape_create_load_unload_cmd(ide_drive_t *drive,
1409 struct ide_atapi_pc *pc, int cmd)
1da177e4
LT		 1410{
1411 idetape_init_pc(pc);
90699ce2 1412 pc->c[0] = START_STOP;
1da177e4 1413 pc->c[4] = cmd;
346331f8 1414 pc->flags |= PC_FLAG_WAIT_FOR_DSC;
1da177e4
LT		 1415}
1416
1417static int idetape_wait_ready(ide_drive_t *drive, unsigned long timeout)
1418{
1419 idetape_tape_t *tape = drive->driver_data;
d236d74c 1420 struct ide_atapi_pc pc;
1da177e4
LT		 1421 int load_attempted = 0;
1422
3c98bf34 1423 /* Wait for the tape to become ready */
346331f8 1424 set_bit(IDETAPE_FLAG_MEDIUM_PRESENT, &tape->flags);
1da177e4
LT		 1425 timeout += jiffies;
1426 while (time_before(jiffies, timeout)) {
1427 idetape_create_test_unit_ready_cmd(&pc);
ea1ab3d3 1428 if (!idetape_queue_pc_tail(drive, &pc))
1da177e4
LT		 1429 return 0;
1430 if ((tape->sense_key == 2 && tape->asc == 4 && tape->ascq == 2)
3c98bf34
BP		 1431 || (tape->asc == 0x3A)) {
1432 /* no media */
1da177e4
LT		 1433 if (load_attempted)
1434 return -ENOMEDIUM;
5a04cfa9
BP		 1435 idetape_create_load_unload_cmd(drive, &pc,
1436 IDETAPE_LU_LOAD_MASK);
ea1ab3d3 1437 idetape_queue_pc_tail(drive, &pc);
1da177e4
LT		 1438 load_attempted = 1;
1439 /* not about to be ready */
1440 } else if (!(tape->sense_key == 2 && tape->asc == 4 &&
1441 (tape->ascq == 1 || tape->ascq == 8)))
1442 return -EIO;
80ce45fd 1443 msleep(100);
1da177e4
LT		 1444 }
1445 return -EIO;
1446}
1447
5a04cfa9 1448static int idetape_flush_tape_buffers(ide_drive_t *drive)
1da177e4 1449{
d236d74c 1450 struct ide_atapi_pc pc;
1da177e4
LT		 1451 int rc;
1452
1453 idetape_create_write_filemark_cmd(drive, &pc, 0);
5a04cfa9
BP		 1454 rc = idetape_queue_pc_tail(drive, &pc);
1455 if (rc)
1da177e4
LT		 1456 return rc;
1457 idetape_wait_ready(drive, 60 * 5 * HZ);
1458 return 0;
1459}
1460
d236d74c 1461static void idetape_create_read_position_cmd(struct ide_atapi_pc *pc)
1da177e4
LT		 1462{
1463 idetape_init_pc(pc);
90699ce2 1464 pc->c[0] = READ_POSITION;
d236d74c 1465 pc->req_xfer = 20;
1da177e4
LT		 1466}
1467
5a04cfa9 1468static int idetape_read_position(ide_drive_t *drive)
1da177e4
LT		 1469{
1470 idetape_tape_t *tape = drive->driver_data;
d236d74c 1471 struct ide_atapi_pc pc;
1da177e4
LT		 1472 int position;
1473
8004a8c9 1474 debug_log(DBG_PROCS, "Enter %s\n", __func__);
1da177e4
LT		 1475
1476 idetape_create_read_position_cmd(&pc);
1477 if (idetape_queue_pc_tail(drive, &pc))
1478 return -1;
54bb2074 1479 position = tape->first_frame;
1da177e4
LT		 1480 return position;
1481}
1482
d236d74c
BP		 1483static void idetape_create_locate_cmd(ide_drive_t *drive,
1484 struct ide_atapi_pc *pc,
5a04cfa9 1485 unsigned int block, u8 partition, int skip)
1da177e4
LT		 1486{
1487 idetape_init_pc(pc);
90699ce2 1488 pc->c[0] = POSITION_TO_ELEMENT;
1da177e4 1489 pc->c[1] = 2;
860ff5ec 1490 put_unaligned(cpu_to_be32(block), (unsigned int *) &pc->c[3]);
1da177e4 1491 pc->c[8] = partition;
346331f8 1492 pc->flags |= PC_FLAG_WAIT_FOR_DSC;
1da177e4
LT		 1493}
1494
d236d74c
BP		 1495static int idetape_create_prevent_cmd(ide_drive_t *drive,
1496 struct ide_atapi_pc *pc, int prevent)
1da177e4
LT		 1497{
1498 idetape_tape_t *tape = drive->driver_data;
1499
b6422013
BP		 1500 /* device supports locking according to capabilities page */
1501 if (!(tape->caps[6] & 0x01))
1da177e4
LT		 1502 return 0;
1503
1504 idetape_init_pc(pc);
90699ce2 1505 pc->c[0] = ALLOW_MEDIUM_REMOVAL;
1da177e4 1506 pc->c[4] = prevent;
1da177e4
LT		 1507 return 1;
1508}
1509
ec0fdb01 1510static void __ide_tape_discard_merge_buffer(ide_drive_t *drive)
1da177e4
LT		 1511{
1512 idetape_tape_t *tape = drive->driver_data;
1da177e4 1513
54abf37e 1514 if (tape->chrdev_dir != IDETAPE_DIR_READ)
9798630a 1515 return;
1da177e4 1516
83042b24 1517 clear_bit(IDETAPE_FLAG_FILEMARK, &tape->flags);
01a63aeb 1518 tape->merge_bh_size = 0;
077e3bdb
BP		 1519 if (tape->merge_bh != NULL) {
1520 ide_tape_kfree_buffer(tape);
1521 tape->merge_bh = NULL;
1da177e4
LT		 1522 }
1523
54abf37e 1524 tape->chrdev_dir = IDETAPE_DIR_NONE;
1da177e4
LT		 1525}
1526
1527/*
3c98bf34
BP		 1528 * Position the tape to the requested block using the LOCATE packet command.
1529 * A READ POSITION command is then issued to check where we are positioned. Like
1530 * all higher level operations, we queue the commands at the tail of the request
1531 * queue and wait for their completion.
1da177e4 1532 */
5a04cfa9
BP		 1533static int idetape_position_tape(ide_drive_t *drive, unsigned int block,
1534 u8 partition, int skip)
1da177e4
LT		 1535{
1536 idetape_tape_t *tape = drive->driver_data;
1537 int retval;
d236d74c 1538 struct ide_atapi_pc pc;
1da177e4 1539
54abf37e 1540 if (tape->chrdev_dir == IDETAPE_DIR_READ)
ec0fdb01 1541 __ide_tape_discard_merge_buffer(drive);
1da177e4
LT		 1542 idetape_wait_ready(drive, 60 * 5 * HZ);
1543 idetape_create_locate_cmd(drive, &pc, block, partition, skip);
1544 retval = idetape_queue_pc_tail(drive, &pc);
1545 if (retval)
1546 return (retval);
1547
1548 idetape_create_read_position_cmd(&pc);
1549 return (idetape_queue_pc_tail(drive, &pc));
1550}
1551
ec0fdb01 1552static void ide_tape_discard_merge_buffer(ide_drive_t *drive,
5a04cfa9 1553 int restore_position)
1da177e4
LT		 1554{
1555 idetape_tape_t *tape = drive->driver_data;
1da177e4
LT		 1556 int seek, position;
1557
ec0fdb01 1558 __ide_tape_discard_merge_buffer(drive);
1da177e4
LT		 1559 if (restore_position) {
1560 position = idetape_read_position(drive);
9798630a 1561 seek = position > 0 ? position : 0;
1da177e4 1562 if (idetape_position_tape(drive, seek, 0, 0)) {
5a04cfa9 1563 printk(KERN_INFO "ide-tape: %s: position_tape failed in"
ec0fdb01 1564 " %s\n", tape->name, __func__);
1da177e4
LT		 1565 return;
1566 }
1567 }
1568}
1569
1570/*
3c98bf34
BP		 1571 * Generate a read/write request for the block device interface and wait for it
1572 * to be serviced.
1da177e4 1573 */
5a04cfa9
BP		 1574static int idetape_queue_rw_tail(ide_drive_t *drive, int cmd, int blocks,
1575 struct idetape_bh *bh)
1da177e4
LT		 1576{
1577 idetape_tape_t *tape = drive->driver_data;
64ea1b4a
FT		 1578 struct request *rq;
1579 int ret, errors;
1da177e4 1580
8004a8c9
BP		 1581 debug_log(DBG_SENSE, "%s: cmd=%d\n", __func__, cmd);
1582
64ea1b4a
FT		 1583 rq = blk_get_request(drive->queue, READ, __GFP_WAIT);
1584 rq->cmd_type = REQ_TYPE_SPECIAL;
1585 rq->cmd[0] = cmd;
1586 rq->rq_disk = tape->disk;
1587 rq->special = (void *)bh;
1588 rq->sector = tape->first_frame;
1589 rq->nr_sectors = blocks;
1590 rq->current_nr_sectors = blocks;
1591 blk_execute_rq(drive->queue, tape->disk, rq, 0);
1592
1593 errors = rq->errors;
1594 ret = tape->blk_size * (blocks - rq->current_nr_sectors);
1595 blk_put_request(rq);
1da177e4
LT		 1596
1597 if ((cmd & (REQ_IDETAPE_READ | REQ_IDETAPE_WRITE)) == 0)
1598 return 0;
1599
077e3bdb
BP		 1600 if (tape->merge_bh)
1601 idetape_init_merge_buffer(tape);
64ea1b4a 1602 if (errors == IDETAPE_ERROR_GENERAL)
1da177e4 1603 return -EIO;
64ea1b4a 1604 return ret;
1da177e4
LT		 1605}
1606
d236d74c 1607static void idetape_create_inquiry_cmd(struct ide_atapi_pc *pc)
1da177e4
LT		 1608{
1609 idetape_init_pc(pc);
90699ce2 1610 pc->c[0] = INQUIRY;
5a04cfa9 1611 pc->c[4] = 254;
d236d74c 1612 pc->req_xfer = 254;
1da177e4
LT		 1613}
1614
d236d74c
BP		 1615static void idetape_create_rewind_cmd(ide_drive_t *drive,
1616 struct ide_atapi_pc *pc)
1da177e4
LT		 1617{
1618 idetape_init_pc(pc);
90699ce2 1619 pc->c[0] = REZERO_UNIT;
346331f8 1620 pc->flags |= PC_FLAG_WAIT_FOR_DSC;
1da177e4
LT		 1621}
1622
d236d74c 1623static void idetape_create_erase_cmd(struct ide_atapi_pc *pc)
1da177e4
LT		 1624{
1625 idetape_init_pc(pc);
90699ce2 1626 pc->c[0] = ERASE;
1da177e4 1627 pc->c[1] = 1;
346331f8 1628 pc->flags |= PC_FLAG_WAIT_FOR_DSC;
1da177e4
LT		 1629}
1630
d236d74c 1631static void idetape_create_space_cmd(struct ide_atapi_pc *pc, int count, u8 cmd)
1da177e4
LT		 1632{
1633 idetape_init_pc(pc);
90699ce2 1634 pc->c[0] = SPACE;
860ff5ec 1635 put_unaligned(cpu_to_be32(count), (unsigned int *) &pc->c[1]);
1da177e4 1636 pc->c[1] = cmd;
346331f8 1637 pc->flags |= PC_FLAG_WAIT_FOR_DSC;
1da177e4
LT		 1638}
1639
97c566ce 1640/* Queue up a character device originated write request. */
5a04cfa9 1641static int idetape_add_chrdev_write_request(ide_drive_t *drive, int blocks)
1da177e4
LT		 1642{
1643 idetape_tape_t *tape = drive->driver_data;
1da177e4 1644
8004a8c9 1645 debug_log(DBG_CHRDEV, "Enter %s\n", __func__);
1da177e4 1646
0aa4b01e 1647 return idetape_queue_rw_tail(drive, REQ_IDETAPE_WRITE,
077e3bdb 1648 blocks, tape->merge_bh);
1da177e4
LT		 1649}
1650
d9df937a 1651static void ide_tape_flush_merge_buffer(ide_drive_t *drive)
1da177e4
LT		 1652{
1653 idetape_tape_t *tape = drive->driver_data;
1654 int blocks, min;
1655 struct idetape_bh *bh;
55a5d291 1656
54abf37e 1657 if (tape->chrdev_dir != IDETAPE_DIR_WRITE) {
077e3bdb 1658 printk(KERN_ERR "ide-tape: bug: Trying to empty merge buffer"
5a04cfa9 1659 " but we are not writing.\n");
1da177e4
LT		 1660 return;
1661 }
01a63aeb 1662 if (tape->merge_bh_size > tape->buffer_size) {
1da177e4 1663 printk(KERN_ERR "ide-tape: bug: merge_buffer too big\n");
01a63aeb 1664 tape->merge_bh_size = tape->buffer_size;
1da177e4 1665 }
01a63aeb
BP		 1666 if (tape->merge_bh_size) {
1667 blocks = tape->merge_bh_size / tape->blk_size;
1668 if (tape->merge_bh_size % tape->blk_size) {
1da177e4
LT		 1669 unsigned int i;
1670
1671 blocks++;
01a63aeb 1672 i = tape->blk_size - tape->merge_bh_size %
54bb2074 1673 tape->blk_size;
1da177e4
LT		 1674 bh = tape->bh->b_reqnext;
1675 while (bh) {
1676 atomic_set(&bh->b_count, 0);
1677 bh = bh->b_reqnext;
1678 }
1679 bh = tape->bh;
1680 while (i) {
1681 if (bh == NULL) {
5a04cfa9
BP		 1682 printk(KERN_INFO "ide-tape: bug,"
1683 " bh NULL\n");
1da177e4
LT		 1684 break;
1685 }
5a04cfa9
BP		 1686 min = min(i, (unsigned int)(bh->b_size -
1687 atomic_read(&bh->b_count)));
1688 memset(bh->b_data + atomic_read(&bh->b_count),
1689 0, min);
1da177e4
LT		 1690 atomic_add(min, &bh->b_count);
1691 i -= min;
1692 bh = bh->b_reqnext;
1693 }
1694 }
1695 (void) idetape_add_chrdev_write_request(drive, blocks);
01a63aeb 1696 tape->merge_bh_size = 0;
1da177e4 1697 }
077e3bdb
BP		 1698 if (tape->merge_bh != NULL) {
1699 ide_tape_kfree_buffer(tape);
1700 tape->merge_bh = NULL;
1da177e4 1701 }
54abf37e 1702 tape->chrdev_dir = IDETAPE_DIR_NONE;
1da177e4
LT		 1703}
1704
83042b24 1705static int idetape_init_read(ide_drive_t *drive)
1da177e4
LT		 1706{
1707 idetape_tape_t *tape = drive->driver_data;
1da177e4 1708 int bytes_read;
1da177e4
LT		 1709
1710 /* Initialize read operation */
54abf37e
BP		 1711 if (tape->chrdev_dir != IDETAPE_DIR_READ) {
1712 if (tape->chrdev_dir == IDETAPE_DIR_WRITE) {
d9df937a 1713 ide_tape_flush_merge_buffer(drive);
1da177e4
LT		 1714 idetape_flush_tape_buffers(drive);
1715 }
077e3bdb 1716 if (tape->merge_bh || tape->merge_bh_size) {
01a63aeb 1717 printk(KERN_ERR "ide-tape: merge_bh_size should be"
5a04cfa9 1718 " 0 now\n");
01a63aeb 1719 tape->merge_bh_size = 0;
1da177e4 1720 }
077e3bdb
BP		 1721 tape->merge_bh = ide_tape_kmalloc_buffer(tape, 0, 0);
1722 if (!tape->merge_bh)
1da177e4 1723 return -ENOMEM;
54abf37e 1724 tape->chrdev_dir = IDETAPE_DIR_READ;
1da177e4
LT		 1725
1726 /*
3c98bf34
BP		 1727 * Issue a read 0 command to ensure that DSC handshake is
1728 * switched from completion mode to buffer available mode.
1729 * No point in issuing this if DSC overlap isn't supported, some
1730 * drives (Seagate STT3401A) will return an error.
1da177e4
LT		 1731 */
1732 if (drive->dsc_overlap) {
5a04cfa9
BP		 1733 bytes_read = idetape_queue_rw_tail(drive,
1734 REQ_IDETAPE_READ, 0,
077e3bdb 1735 tape->merge_bh);
1da177e4 1736 if (bytes_read < 0) {
077e3bdb
BP		 1737 ide_tape_kfree_buffer(tape);
1738 tape->merge_bh = NULL;
54abf37e 1739 tape->chrdev_dir = IDETAPE_DIR_NONE;
1da177e4
LT		 1740 return bytes_read;
1741 }
1742 }
1743 }
5e69bd95 1744
1da177e4
LT		 1745 return 0;
1746}
1747
5bd50dc6 1748/* called from idetape_chrdev_read() to service a chrdev read request. */
5a04cfa9 1749static int idetape_add_chrdev_read_request(ide_drive_t *drive, int blocks)
1da177e4
LT		 1750{
1751 idetape_tape_t *tape = drive->driver_data;
1da177e4 1752
8004a8c9 1753 debug_log(DBG_PROCS, "Enter %s, %d blocks\n", __func__, blocks);
1da177e4 1754
3c98bf34 1755 /* If we are at a filemark, return a read length of 0 */
346331f8 1756 if (test_bit(IDETAPE_FLAG_FILEMARK, &tape->flags))
1da177e4
LT		 1757 return 0;
1758
83042b24 1759 idetape_init_read(drive);
5e69bd95 1760
5e69bd95 1761 return idetape_queue_rw_tail(drive, REQ_IDETAPE_READ, blocks,
077e3bdb 1762 tape->merge_bh);
1da177e4
LT		 1763}
1764
5a04cfa9 1765static void idetape_pad_zeros(ide_drive_t *drive, int bcount)
1da177e4
LT		 1766{
1767 idetape_tape_t *tape = drive->driver_data;
1768 struct idetape_bh *bh;
1769 int blocks;
3c98bf34 1770
1da177e4
LT		 1771 while (bcount) {
1772 unsigned int count;
1773
077e3bdb 1774 bh = tape->merge_bh;
f73850a3 1775 count = min(tape->buffer_size, bcount);
1da177e4 1776 bcount -= count;
54bb2074 1777 blocks = count / tape->blk_size;
1da177e4 1778 while (count) {
5a04cfa9
BP		 1779 atomic_set(&bh->b_count,
1780 min(count, (unsigned int)bh->b_size));
1da177e4
LT		 1781 memset(bh->b_data, 0, atomic_read(&bh->b_count));
1782 count -= atomic_read(&bh->b_count);
1783 bh = bh->b_reqnext;
1784 }
5a04cfa9 1785 idetape_queue_rw_tail(drive, REQ_IDETAPE_WRITE, blocks,
077e3bdb 1786 tape->merge_bh);
1da177e4
LT		 1787 }
1788}
1789
1da177e4 1790/*
3c98bf34
BP		 1791 * Rewinds the tape to the Beginning Of the current Partition (BOP). We
1792 * currently support only one partition.
1793 */
5a04cfa9 1794static int idetape_rewind_tape(ide_drive_t *drive)
1da177e4
LT		 1795{
1796 int retval;
d236d74c 1797 struct ide_atapi_pc pc;
8004a8c9
BP		 1798 idetape_tape_t *tape;
1799 tape = drive->driver_data;
1800
1801 debug_log(DBG_SENSE, "Enter %s\n", __func__);
1802
1da177e4
LT		 1803 idetape_create_rewind_cmd(drive, &pc);
1804 retval = idetape_queue_pc_tail(drive, &pc);
1805 if (retval)
1806 return retval;
1807
1808 idetape_create_read_position_cmd(&pc);
1809 retval = idetape_queue_pc_tail(drive, &pc);
1810 if (retval)
1811 return retval;
1812 return 0;
1813}
1814
3c98bf34 1815/* mtio.h compatible commands should be issued to the chrdev interface. */
5a04cfa9
BP		 1816static int idetape_blkdev_ioctl(ide_drive_t *drive, unsigned int cmd,
1817 unsigned long arg)
1da177e4
LT		 1818{
1819 idetape_tape_t *tape = drive->driver_data;
1da177e4
LT		 1820 void __user *argp = (void __user *)arg;
1821
d59823fa
BP		 1822 struct idetape_config {
1823 int dsc_rw_frequency;
1824 int dsc_media_access_frequency;
1825 int nr_stages;
1826 } config;
1827
8004a8c9
BP		 1828 debug_log(DBG_PROCS, "Enter %s\n", __func__);
1829
1da177e4 1830 switch (cmd) {
5a04cfa9
BP		 1831 case 0x0340:
1832 if (copy_from_user(&config, argp, sizeof(config)))
1833 return -EFAULT;
1834 tape->best_dsc_rw_freq = config.dsc_rw_frequency;
5a04cfa9
BP		 1835 break;
1836 case 0x0350:
1837 config.dsc_rw_frequency = (int) tape->best_dsc_rw_freq;
83042b24 1838 config.nr_stages = 1;
5a04cfa9
BP		 1839 if (copy_to_user(argp, &config, sizeof(config)))
1840 return -EFAULT;
1841 break;
1842 default:
1843 return -EIO;
1da177e4
LT		 1844 }
1845 return 0;
1846}
1847
5a04cfa9
BP		 1848static int idetape_space_over_filemarks(ide_drive_t *drive, short mt_op,
1849 int mt_count)
1da177e4
LT		 1850{
1851 idetape_tape_t *tape = drive->driver_data;
d236d74c 1852 struct ide_atapi_pc pc;
5a04cfa9 1853 int retval, count = 0;
b6422013 1854 int sprev = !!(tape->caps[4] & 0x20);
1da177e4
LT		 1855
1856 if (mt_count == 0)
1857 return 0;
1858 if (MTBSF == mt_op || MTBSFM == mt_op) {
b6422013 1859 if (!sprev)
1da177e4 1860 return -EIO;
5a04cfa9 1861 mt_count = -mt_count;
1da177e4
LT		 1862 }
1863
54abf37e 1864 if (tape->chrdev_dir == IDETAPE_DIR_READ) {
01a63aeb 1865 tape->merge_bh_size = 0;
346331f8 1866 if (test_and_clear_bit(IDETAPE_FLAG_FILEMARK, &tape->flags))
1da177e4 1867 ++count;
ec0fdb01 1868 ide_tape_discard_merge_buffer(drive, 0);
1da177e4
LT		 1869 }
1870
1da177e4 1871 switch (mt_op) {
5a04cfa9
BP		 1872 case MTFSF:
1873 case MTBSF:
1874 idetape_create_space_cmd(&pc, mt_count - count,
1875 IDETAPE_SPACE_OVER_FILEMARK);
1876 return idetape_queue_pc_tail(drive, &pc);
1877 case MTFSFM:
1878 case MTBSFM:
1879 if (!sprev)
1880 return -EIO;
1881 retval = idetape_space_over_filemarks(drive, MTFSF,
1882 mt_count - count);
1883 if (retval)
1884 return retval;
1885 count = (MTBSFM == mt_op ? 1 : -1);
1886 return idetape_space_over_filemarks(drive, MTFSF, count);
1887 default:
1888 printk(KERN_ERR "ide-tape: MTIO operation %d not supported\n",
1889 mt_op);
1890 return -EIO;
1da177e4
LT		 1891 }
1892}
1893
1da177e4 1894/*
3c98bf34 1895 * Our character device read / write functions.
1da177e4 1896 *
3c98bf34
BP		 1897 * The tape is optimized to maximize throughput when it is transferring an
1898 * integral number of the "continuous transfer limit", which is a parameter of
1899 * the specific tape (26kB on my particular tape, 32kB for Onstream).
1da177e4 1900 *
3c98bf34
BP		 1901 * As of version 1.3 of the driver, the character device provides an abstract
1902 * continuous view of the media - any mix of block sizes (even 1 byte) on the
1903 * same backup/restore procedure is supported. The driver will internally
1904 * convert the requests to the recommended transfer unit, so that an unmatch
1905 * between the user's block size to the recommended size will only result in a
1906 * (slightly) increased driver overhead, but will no longer hit performance.
1907 * This is not applicable to Onstream.
1da177e4 1908 */
5a04cfa9
BP		 1909static ssize_t idetape_chrdev_read(struct file *file, char __user *buf,
1910 size_t count, loff_t *ppos)
1da177e4
LT		 1911{
1912 struct ide_tape_obj *tape = ide_tape_f(file);
1913 ide_drive_t *drive = tape->drive;
5a04cfa9 1914 ssize_t bytes_read, temp, actually_read = 0, rc;
dcd96379 1915 ssize_t ret = 0;
b6422013 1916 u16 ctl = *(u16 *)&tape->caps[12];
1da177e4 1917
8004a8c9 1918 debug_log(DBG_CHRDEV, "Enter %s, count %Zd\n", __func__, count);
1da177e4 1919
54abf37e 1920 if (tape->chrdev_dir != IDETAPE_DIR_READ) {
346331f8 1921 if (test_bit(IDETAPE_FLAG_DETECT_BS, &tape->flags))
54bb2074
BP		 1922 if (count > tape->blk_size &&
1923 (count % tape->blk_size) == 0)
1924 tape->user_bs_factor = count / tape->blk_size;
1da177e4 1925 }
83042b24 1926 rc = idetape_init_read(drive);
8d06bfad 1927 if (rc < 0)
1da177e4
LT		 1928 return rc;
1929 if (count == 0)
1930 return (0);
01a63aeb
BP		 1931 if (tape->merge_bh_size) {
1932 actually_read = min((unsigned int)(tape->merge_bh_size),
5a04cfa9 1933 (unsigned int)count);
99d74e61 1934 if (idetape_copy_stage_to_user(tape, buf, actually_read))
dcd96379 1935 ret = -EFAULT;
1da177e4 1936 buf += actually_read;
01a63aeb 1937 tape->merge_bh_size -= actually_read;
1da177e4
LT		 1938 count -= actually_read;
1939 }
f73850a3 1940 while (count >= tape->buffer_size) {
b6422013 1941 bytes_read = idetape_add_chrdev_read_request(drive, ctl);
1da177e4
LT		 1942 if (bytes_read <= 0)
1943 goto finish;
99d74e61 1944 if (idetape_copy_stage_to_user(tape, buf, bytes_read))
dcd96379 1945 ret = -EFAULT;
1da177e4
LT		 1946 buf += bytes_read;
1947 count -= bytes_read;
1948 actually_read += bytes_read;
1949 }
1950 if (count) {
b6422013 1951 bytes_read = idetape_add_chrdev_read_request(drive, ctl);
1da177e4
LT		 1952 if (bytes_read <= 0)
1953 goto finish;
1954 temp = min((unsigned long)count, (unsigned long)bytes_read);
99d74e61 1955 if (idetape_copy_stage_to_user(tape, buf, temp))
dcd96379 1956 ret = -EFAULT;
1da177e4 1957 actually_read += temp;
01a63aeb 1958 tape->merge_bh_size = bytes_read-temp;
1da177e4
LT		 1959 }
1960finish:
346331f8 1961 if (!actually_read && test_bit(IDETAPE_FLAG_FILEMARK, &tape->flags)) {
8004a8c9
BP		 1962 debug_log(DBG_SENSE, "%s: spacing over filemark\n", tape->name);
1963
1da177e4
LT		 1964 idetape_space_over_filemarks(drive, MTFSF, 1);
1965 return 0;
1966 }
dcd96379 1967
5a04cfa9 1968 return ret ? ret : actually_read;
1da177e4
LT		 1969}
1970
5a04cfa9 1971static ssize_t idetape_chrdev_write(struct file *file, const char __user *buf,
1da177e4
LT		 1972 size_t count, loff_t *ppos)
1973{
1974 struct ide_tape_obj *tape = ide_tape_f(file);
1975 ide_drive_t *drive = tape->drive;
dcd96379
DW		 1976 ssize_t actually_written = 0;
1977 ssize_t ret = 0;
b6422013 1978 u16 ctl = *(u16 *)&tape->caps[12];
1da177e4
LT		 1979
1980 /* The drive is write protected. */
1981 if (tape->write_prot)
1982 return -EACCES;
1983
8004a8c9 1984 debug_log(DBG_CHRDEV, "Enter %s, count %Zd\n", __func__, count);
1da177e4
LT		 1985
1986 /* Initialize write operation */
54abf37e
BP		 1987 if (tape->chrdev_dir != IDETAPE_DIR_WRITE) {
1988 if (tape->chrdev_dir == IDETAPE_DIR_READ)
ec0fdb01 1989 ide_tape_discard_merge_buffer(drive, 1);
077e3bdb 1990 if (tape->merge_bh || tape->merge_bh_size) {
01a63aeb 1991 printk(KERN_ERR "ide-tape: merge_bh_size "
1da177e4 1992 "should be 0 now\n");
01a63aeb 1993 tape->merge_bh_size = 0;
1da177e4 1994 }
077e3bdb
BP		 1995 tape->merge_bh = ide_tape_kmalloc_buffer(tape, 0, 0);
1996 if (!tape->merge_bh)
1da177e4 1997 return -ENOMEM;
54abf37e 1998 tape->chrdev_dir = IDETAPE_DIR_WRITE;
077e3bdb 1999 idetape_init_merge_buffer(tape);
1da177e4
LT		 2000
2001 /*
3c98bf34
BP		 2002 * Issue a write 0 command to ensure that DSC handshake is
2003 * switched from completion mode to buffer available mode. No
2004 * point in issuing this if DSC overlap isn't supported, some
2005 * drives (Seagate STT3401A) will return an error.
1da177e4
LT		 2006 */
2007 if (drive->dsc_overlap) {
5a04cfa9
BP		 2008 ssize_t retval = idetape_queue_rw_tail(drive,
2009 REQ_IDETAPE_WRITE, 0,
077e3bdb 2010 tape->merge_bh);
1da177e4 2011 if (retval < 0) {
077e3bdb
BP		 2012 ide_tape_kfree_buffer(tape);
2013 tape->merge_bh = NULL;
54abf37e 2014 tape->chrdev_dir = IDETAPE_DIR_NONE;
1da177e4
LT		 2015 return retval;
2016 }
2017 }
2018 }
2019 if (count == 0)
2020 return (0);
01a63aeb
BP		 2021 if (tape->merge_bh_size) {
2022 if (tape->merge_bh_size >= tape->buffer_size) {
5a04cfa9 2023 printk(KERN_ERR "ide-tape: bug: merge buf too big\n");
01a63aeb 2024 tape->merge_bh_size = 0;
1da177e4 2025 }
5a04cfa9 2026 actually_written = min((unsigned int)
01a63aeb 2027 (tape->buffer_size - tape->merge_bh_size),
5a04cfa9 2028 (unsigned int)count);
8646c88f 2029 if (idetape_copy_stage_from_user(tape, buf, actually_written))
dcd96379 2030 ret = -EFAULT;
1da177e4 2031 buf += actually_written;
01a63aeb 2032 tape->merge_bh_size += actually_written;
1da177e4
LT		 2033 count -= actually_written;
2034
01a63aeb 2035 if (tape->merge_bh_size == tape->buffer_size) {
dcd96379 2036 ssize_t retval;
01a63aeb 2037 tape->merge_bh_size = 0;
b6422013 2038 retval = idetape_add_chrdev_write_request(drive, ctl);
1da177e4
LT		 2039 if (retval <= 0)
2040 return (retval);
2041 }
2042 }
f73850a3 2043 while (count >= tape->buffer_size) {
dcd96379 2044 ssize_t retval;
f73850a3 2045 if (idetape_copy_stage_from_user(tape, buf, tape->buffer_size))
dcd96379 2046 ret = -EFAULT;
f73850a3
BP		 2047 buf += tape->buffer_size;
2048 count -= tape->buffer_size;
b6422013 2049 retval = idetape_add_chrdev_write_request(drive, ctl);
f73850a3 2050 actually_written += tape->buffer_size;
1da177e4
LT		 2051 if (retval <= 0)
2052 return (retval);
2053 }
2054 if (count) {
2055 actually_written += count;
8646c88f 2056 if (idetape_copy_stage_from_user(tape, buf, count))
dcd96379 2057 ret = -EFAULT;
01a63aeb 2058 tape->merge_bh_size += count;
1da177e4 2059 }
5a04cfa9 2060 return ret ? ret : actually_written;
1da177e4
LT		 2061}
2062
5a04cfa9 2063static int idetape_write_filemark(ide_drive_t *drive)
1da177e4 2064{
d236d74c 2065 struct ide_atapi_pc pc;
1da177e4
LT		 2066
2067 /* Write a filemark */
2068 idetape_create_write_filemark_cmd(drive, &pc, 1);
2069 if (idetape_queue_pc_tail(drive, &pc)) {
2070 printk(KERN_ERR "ide-tape: Couldn't write a filemark\n");
2071 return -EIO;
2072 }
2073 return 0;
2074}
2075
2076/*
d99c9da2
BP		 2077 * Called from idetape_chrdev_ioctl when the general mtio MTIOCTOP ioctl is
2078 * requested.
1da177e4 2079 *
d99c9da2
BP		 2080 * Note: MTBSF and MTBSFM are not supported when the tape doesn't support
2081 * spacing over filemarks in the reverse direction. In this case, MTFSFM is also
5bd50dc6 2082 * usually not supported.
1da177e4 2083 *
d99c9da2 2084 * The following commands are currently not supported:
1da177e4 2085 *
d99c9da2
BP		 2086 * MTFSS, MTBSS, MTWSM, MTSETDENSITY, MTSETDRVBUFFER, MT_ST_BOOLEANS,
2087 * MT_ST_WRITE_THRESHOLD.
1da177e4 2088 */
d99c9da2 2089static int idetape_mtioctop(ide_drive_t *drive, short mt_op, int mt_count)
1da177e4
LT		 2090{
2091 idetape_tape_t *tape = drive->driver_data;
d236d74c 2092 struct ide_atapi_pc pc;
5a04cfa9 2093 int i, retval;
1da177e4 2094
8004a8c9
BP		 2095 debug_log(DBG_ERR, "Handling MTIOCTOP ioctl: mt_op=%d, mt_count=%d\n",
2096 mt_op, mt_count);
5a04cfa9 2097
1da177e4 2098 switch (mt_op) {
5a04cfa9
BP		 2099 case MTFSF:
2100 case MTFSFM:
2101 case MTBSF:
2102 case MTBSFM:
2103 if (!mt_count)
2104 return 0;
2105 return idetape_space_over_filemarks(drive, mt_op, mt_count);
2106 default:
2107 break;
1da177e4 2108 }
5a04cfa9 2109
1da177e4 2110 switch (mt_op) {
5a04cfa9
BP		 2111 case MTWEOF:
2112 if (tape->write_prot)
2113 return -EACCES;
ec0fdb01 2114 ide_tape_discard_merge_buffer(drive, 1);
5a04cfa9
BP		 2115 for (i = 0; i < mt_count; i++) {
2116 retval = idetape_write_filemark(drive);
2117 if (retval)
2118 return retval;
2119 }
2120 return 0;
2121 case MTREW:
ec0fdb01 2122 ide_tape_discard_merge_buffer(drive, 0);
5a04cfa9
BP		 2123 if (idetape_rewind_tape(drive))
2124 return -EIO;
2125 return 0;
2126 case MTLOAD:
ec0fdb01 2127 ide_tape_discard_merge_buffer(drive, 0);
5a04cfa9
BP		 2128 idetape_create_load_unload_cmd(drive, &pc,
2129 IDETAPE_LU_LOAD_MASK);
2130 return idetape_queue_pc_tail(drive, &pc);
2131 case MTUNLOAD:
2132 case MTOFFL:
2133 /*
2134 * If door is locked, attempt to unlock before
2135 * attempting to eject.
2136 */
2137 if (tape->door_locked) {
2138 if (idetape_create_prevent_cmd(drive, &pc, 0))
2139 if (!idetape_queue_pc_tail(drive, &pc))
2140 tape->door_locked = DOOR_UNLOCKED;
2141 }
ec0fdb01 2142 ide_tape_discard_merge_buffer(drive, 0);
5a04cfa9
BP		 2143 idetape_create_load_unload_cmd(drive, &pc,
2144 !IDETAPE_LU_LOAD_MASK);
2145 retval = idetape_queue_pc_tail(drive, &pc);
2146 if (!retval)
346331f8 2147 clear_bit(IDETAPE_FLAG_MEDIUM_PRESENT, &tape->flags);
5a04cfa9
BP		 2148 return retval;
2149 case MTNOP:
ec0fdb01 2150 ide_tape_discard_merge_buffer(drive, 0);
5a04cfa9
BP		 2151 return idetape_flush_tape_buffers(drive);
2152 case MTRETEN:
ec0fdb01 2153 ide_tape_discard_merge_buffer(drive, 0);
5a04cfa9
BP		 2154 idetape_create_load_unload_cmd(drive, &pc,
2155 IDETAPE_LU_RETENSION_MASK | IDETAPE_LU_LOAD_MASK);
2156 return idetape_queue_pc_tail(drive, &pc);
2157 case MTEOM:
2158 idetape_create_space_cmd(&pc, 0, IDETAPE_SPACE_TO_EOD);
2159 return idetape_queue_pc_tail(drive, &pc);
2160 case MTERASE:
2161 (void)idetape_rewind_tape(drive);
2162 idetape_create_erase_cmd(&pc);
2163 return idetape_queue_pc_tail(drive, &pc);
2164 case MTSETBLK:
2165 if (mt_count) {
2166 if (mt_count < tape->blk_size ||
2167 mt_count % tape->blk_size)
1da177e4 2168 return -EIO;
5a04cfa9 2169 tape->user_bs_factor = mt_count / tape->blk_size;
346331f8 2170 clear_bit(IDETAPE_FLAG_DETECT_BS, &tape->flags);
5a04cfa9 2171 } else
346331f8 2172 set_bit(IDETAPE_FLAG_DETECT_BS, &tape->flags);
5a04cfa9
BP		 2173 return 0;
2174 case MTSEEK:
ec0fdb01 2175 ide_tape_discard_merge_buffer(drive, 0);
5a04cfa9
BP		 2176 return idetape_position_tape(drive,
2177 mt_count * tape->user_bs_factor, tape->partition, 0);
2178 case MTSETPART:
ec0fdb01 2179 ide_tape_discard_merge_buffer(drive, 0);
5a04cfa9
BP		 2180 return idetape_position_tape(drive, 0, mt_count, 0);
2181 case MTFSR:
2182 case MTBSR:
2183 case MTLOCK:
2184 if (!idetape_create_prevent_cmd(drive, &pc, 1))
1da177e4 2185 return 0;
5a04cfa9
BP		 2186 retval = idetape_queue_pc_tail(drive, &pc);
2187 if (retval)
1da177e4 2188 return retval;
5a04cfa9
BP		 2189 tape->door_locked = DOOR_EXPLICITLY_LOCKED;
2190 return 0;
2191 case MTUNLOCK:
2192 if (!idetape_create_prevent_cmd(drive, &pc, 0))
1da177e4 2193 return 0;
5a04cfa9
BP		 2194 retval = idetape_queue_pc_tail(drive, &pc);
2195 if (retval)
2196 return retval;
2197 tape->door_locked = DOOR_UNLOCKED;
2198 return 0;
2199 default:
2200 printk(KERN_ERR "ide-tape: MTIO operation %d not supported\n",
2201 mt_op);
2202 return -EIO;
1da177e4
LT		 2203 }
2204}
2205
2206/*
d99c9da2
BP		 2207 * Our character device ioctls. General mtio.h magnetic io commands are
2208 * supported here, and not in the corresponding block interface. Our own
2209 * ide-tape ioctls are supported on both interfaces.
1da177e4 2210 */
d99c9da2
BP		 2211static int idetape_chrdev_ioctl(struct inode *inode, struct file *file,
2212 unsigned int cmd, unsigned long arg)
1da177e4
LT		 2213{
2214 struct ide_tape_obj *tape = ide_tape_f(file);
2215 ide_drive_t *drive = tape->drive;
2216 struct mtop mtop;
2217 struct mtget mtget;
2218 struct mtpos mtpos;
54bb2074 2219 int block_offset = 0, position = tape->first_frame;
1da177e4
LT		 2220 void __user *argp = (void __user *)arg;
2221
8004a8c9 2222 debug_log(DBG_CHRDEV, "Enter %s, cmd=%u\n", __func__, cmd);
1da177e4 2223
54abf37e 2224 if (tape->chrdev_dir == IDETAPE_DIR_WRITE) {
d9df937a 2225 ide_tape_flush_merge_buffer(drive);
1da177e4
LT		 2226 idetape_flush_tape_buffers(drive);
2227 }
2228 if (cmd == MTIOCGET || cmd == MTIOCPOS) {
01a63aeb 2229 block_offset = tape->merge_bh_size /
54bb2074 2230 (tape->blk_size * tape->user_bs_factor);
5a04cfa9
BP		 2231 position = idetape_read_position(drive);
2232 if (position < 0)
1da177e4
LT		 2233 return -EIO;
2234 }
2235 switch (cmd) {
5a04cfa9
BP		 2236 case MTIOCTOP:
2237 if (copy_from_user(&mtop, argp, sizeof(struct mtop)))
2238 return -EFAULT;
2239 return idetape_mtioctop(drive, mtop.mt_op, mtop.mt_count);
2240 case MTIOCGET:
2241 memset(&mtget, 0, sizeof(struct mtget));
2242 mtget.mt_type = MT_ISSCSI2;
2243 mtget.mt_blkno = position / tape->user_bs_factor - block_offset;
2244 mtget.mt_dsreg =
2245 ((tape->blk_size * tape->user_bs_factor)
2246 << MT_ST_BLKSIZE_SHIFT) & MT_ST_BLKSIZE_MASK;
2247
2248 if (tape->drv_write_prot)
2249 mtget.mt_gstat |= GMT_WR_PROT(0xffffffff);
2250
2251 if (copy_to_user(argp, &mtget, sizeof(struct mtget)))
2252 return -EFAULT;
2253 return 0;
2254 case MTIOCPOS:
2255 mtpos.mt_blkno = position / tape->user_bs_factor - block_offset;
2256 if (copy_to_user(argp, &mtpos, sizeof(struct mtpos)))
2257 return -EFAULT;
2258 return 0;
2259 default:
2260 if (tape->chrdev_dir == IDETAPE_DIR_READ)
ec0fdb01 2261 ide_tape_discard_merge_buffer(drive, 1);
5a04cfa9 2262 return idetape_blkdev_ioctl(drive, cmd, arg);
1da177e4
LT		 2263 }
2264}
2265
3cffb9ce
BP		 2266/*
2267 * Do a mode sense page 0 with block descriptor and if it succeeds set the tape
2268 * block size with the reported value.
2269 */
2270static void ide_tape_get_bsize_from_bdesc(ide_drive_t *drive)
2271{
2272 idetape_tape_t *tape = drive->driver_data;
d236d74c 2273 struct ide_atapi_pc pc;
3cffb9ce
BP		 2274
2275 idetape_create_mode_sense_cmd(&pc, IDETAPE_BLOCK_DESCRIPTOR);
2276 if (idetape_queue_pc_tail(drive, &pc)) {
2277 printk(KERN_ERR "ide-tape: Can't get block descriptor\n");
54bb2074 2278 if (tape->blk_size == 0) {
3cffb9ce
BP		 2279 printk(KERN_WARNING "ide-tape: Cannot deal with zero "
2280 "block size, assuming 32k\n");
54bb2074 2281 tape->blk_size = 32768;
3cffb9ce
BP		 2282 }
2283 return;
2284 }
d236d74c
BP		 2285 tape->blk_size = (pc.buf[4 + 5] << 16) +
2286 (pc.buf[4 + 6] << 8) +
2287 pc.buf[4 + 7];
2288 tape->drv_write_prot = (pc.buf[2] & 0x80) >> 7;
3cffb9ce 2289}
1da177e4 2290
5a04cfa9 2291static int idetape_chrdev_open(struct inode *inode, struct file *filp)
1da177e4
LT		 2292{
2293 unsigned int minor = iminor(inode), i = minor & ~0xc0;
2294 ide_drive_t *drive;
2295 idetape_tape_t *tape;
d236d74c 2296 struct ide_atapi_pc pc;
1da177e4
LT		 2297 int retval;
2298
8004a8c9
BP		 2299 if (i >= MAX_HWIFS * MAX_DRIVES)
2300 return -ENXIO;
2301
2302 tape = ide_tape_chrdev_get(i);
2303 if (!tape)
2304 return -ENXIO;
2305
2306 debug_log(DBG_CHRDEV, "Enter %s\n", __func__);
2307
1da177e4
LT		 2308 /*
2309 * We really want to do nonseekable_open(inode, filp); here, but some
2310 * versions of tar incorrectly call lseek on tapes and bail out if that
2311 * fails. So we disallow pread() and pwrite(), but permit lseeks.
2312 */
2313 filp->f_mode &= ~(FMODE_PREAD | FMODE_PWRITE);
2314
1da177e4
LT		 2315 drive = tape->drive;
2316
2317 filp->private_data = tape;
2318
346331f8 2319 if (test_and_set_bit(IDETAPE_FLAG_BUSY, &tape->flags)) {
1da177e4
LT		 2320 retval = -EBUSY;
2321 goto out_put_tape;
2322 }
2323
2324 retval = idetape_wait_ready(drive, 60 * HZ);
2325 if (retval) {
346331f8 2326 clear_bit(IDETAPE_FLAG_BUSY, &tape->flags);
1da177e4
LT		 2327 printk(KERN_ERR "ide-tape: %s: drive not ready\n", tape->name);
2328 goto out_put_tape;
2329 }
2330
2331 idetape_read_position(drive);
346331f8 2332 if (!test_bit(IDETAPE_FLAG_ADDRESS_VALID, &tape->flags))
1da177e4
LT		 2333 (void)idetape_rewind_tape(drive);
2334
1da177e4 2335 /* Read block size and write protect status from drive. */
3cffb9ce 2336 ide_tape_get_bsize_from_bdesc(drive);
1da177e4
LT		 2337
2338 /* Set write protect flag if device is opened as read-only. */
2339 if ((filp->f_flags & O_ACCMODE) == O_RDONLY)
2340 tape->write_prot = 1;
2341 else
2342 tape->write_prot = tape->drv_write_prot;
2343
2344 /* Make sure drive isn't write protected if user wants to write. */
2345 if (tape->write_prot) {
2346 if ((filp->f_flags & O_ACCMODE) == O_WRONLY ||
2347 (filp->f_flags & O_ACCMODE) == O_RDWR) {
346331f8 2348 clear_bit(IDETAPE_FLAG_BUSY, &tape->flags);
1da177e4
LT		 2349 retval = -EROFS;
2350 goto out_put_tape;
2351 }
2352 }
2353
3c98bf34 2354 /* Lock the tape drive door so user can't eject. */
54abf37e 2355 if (tape->chrdev_dir == IDETAPE_DIR_NONE) {
1da177e4
LT		 2356 if (idetape_create_prevent_cmd(drive, &pc, 1)) {
2357 if (!idetape_queue_pc_tail(drive, &pc)) {
2358 if (tape->door_locked != DOOR_EXPLICITLY_LOCKED)
2359 tape->door_locked = DOOR_LOCKED;
2360 }
2361 }
2362 }
1da177e4
LT		 2363 return 0;
2364
2365out_put_tape:
2366 ide_tape_put(tape);
2367 return retval;
2368}
2369
5a04cfa9 2370static void idetape_write_release(ide_drive_t *drive, unsigned int minor)
1da177e4
LT		 2371{
2372 idetape_tape_t *tape = drive->driver_data;
2373
d9df937a 2374 ide_tape_flush_merge_buffer(drive);
077e3bdb
BP		 2375 tape->merge_bh = ide_tape_kmalloc_buffer(tape, 1, 0);
2376 if (tape->merge_bh != NULL) {
54bb2074
BP		 2377 idetape_pad_zeros(drive, tape->blk_size *
2378 (tape->user_bs_factor - 1));
077e3bdb
BP		 2379 ide_tape_kfree_buffer(tape);
2380 tape->merge_bh = NULL;
1da177e4
LT		 2381 }
2382 idetape_write_filemark(drive);
2383 idetape_flush_tape_buffers(drive);
2384 idetape_flush_tape_buffers(drive);
2385}
2386
5a04cfa9 2387static int idetape_chrdev_release(struct inode *inode, struct file *filp)
1da177e4
LT		 2388{
2389 struct ide_tape_obj *tape = ide_tape_f(filp);
2390 ide_drive_t *drive = tape->drive;
d236d74c 2391 struct ide_atapi_pc pc;
1da177e4
LT		 2392 unsigned int minor = iminor(inode);
2393
2394 lock_kernel();
2395 tape = drive->driver_data;
8004a8c9
BP		 2396
2397 debug_log(DBG_CHRDEV, "Enter %s\n", __func__);
1da177e4 2398
54abf37e 2399 if (tape->chrdev_dir == IDETAPE_DIR_WRITE)
1da177e4 2400 idetape_write_release(drive, minor);
54abf37e 2401 if (tape->chrdev_dir == IDETAPE_DIR_READ) {
1da177e4 2402 if (minor < 128)
ec0fdb01 2403 ide_tape_discard_merge_buffer(drive, 1);
1da177e4 2404 }
f64eee7b 2405
346331f8 2406 if (minor < 128 && test_bit(IDETAPE_FLAG_MEDIUM_PRESENT, &tape->flags))
1da177e4 2407 (void) idetape_rewind_tape(drive);
54abf37e 2408 if (tape->chrdev_dir == IDETAPE_DIR_NONE) {
1da177e4
LT		 2409 if (tape->door_locked == DOOR_LOCKED) {
2410 if (idetape_create_prevent_cmd(drive, &pc, 0)) {
2411 if (!idetape_queue_pc_tail(drive, &pc))
2412 tape->door_locked = DOOR_UNLOCKED;
2413 }
2414 }
2415 }
346331f8 2416 clear_bit(IDETAPE_FLAG_BUSY, &tape->flags);
1da177e4
LT		 2417 ide_tape_put(tape);
2418 unlock_kernel();
2419 return 0;
2420}
2421
2422/*
71071b8e 2423 * check the contents of the ATAPI IDENTIFY command results. We return:
1da177e4 2424 *
71071b8e
BP		 2425 * 1 - If the tape can be supported by us, based on the information we have so
2426 * far.
1da177e4 2427 *
71071b8e 2428 * 0 - If this tape driver is not currently supported by us.
1da177e4 2429 */
71071b8e 2430static int idetape_identify_device(ide_drive_t *drive)
1da177e4 2431{
71071b8e 2432 u8 gcw[2], protocol, device_type, removable, packet_size;
1da177e4
LT		 2433
2434 if (drive->id_read == 0)
2435 return 1;
2436
71071b8e 2437 *((unsigned short *) &gcw) = drive->id->config;
1da177e4 2438
71071b8e
BP		 2439 protocol = (gcw[1] & 0xC0) >> 6;
2440 device_type = gcw[1] & 0x1F;
2441 removable = !!(gcw[0] & 0x80);
2442 packet_size = gcw[0] & 0x3;
1da177e4 2443
71071b8e
BP		 2444 /* Check that we can support this device */
2445 if (protocol != 2)
16422de3 2446 printk(KERN_ERR "ide-tape: Protocol (0x%02x) is not ATAPI\n",
71071b8e
BP		 2447 protocol);
2448 else if (device_type != 1)
16422de3 2449 printk(KERN_ERR "ide-tape: Device type (0x%02x) is not set "
71071b8e
BP		 2450 "to tape\n", device_type);
2451 else if (!removable)
1da177e4 2452 printk(KERN_ERR "ide-tape: The removable flag is not set\n");
71071b8e 2453 else if (packet_size != 0) {
24d57f8b
BP		 2454 printk(KERN_ERR "ide-tape: Packet size (0x%02x) is not 12"
2455 " bytes\n", packet_size);
1da177e4
LT		 2456 } else
2457 return 1;
2458 return 0;
2459}
2460
6d29c8f0 2461static void idetape_get_inquiry_results(ide_drive_t *drive)
1da177e4 2462{
1da177e4 2463 idetape_tape_t *tape = drive->driver_data;
d236d74c 2464 struct ide_atapi_pc pc;
41f81d54 2465 char fw_rev[6], vendor_id[10], product_id[18];
6d29c8f0 2466
1da177e4
LT		 2467 idetape_create_inquiry_cmd(&pc);
2468 if (idetape_queue_pc_tail(drive, &pc)) {
6d29c8f0
BP		 2469 printk(KERN_ERR "ide-tape: %s: can't get INQUIRY results\n",
2470 tape->name);
1da177e4
LT		 2471 return;
2472 }
d236d74c
BP		 2473 memcpy(vendor_id, &pc.buf[8], 8);
2474 memcpy(product_id, &pc.buf[16], 16);
2475 memcpy(fw_rev, &pc.buf[32], 4);
41f81d54
BP		 2476
2477 ide_fixstring(vendor_id, 10, 0);
2478 ide_fixstring(product_id, 18, 0);
2479 ide_fixstring(fw_rev, 6, 0);
2480
6d29c8f0 2481 printk(KERN_INFO "ide-tape: %s <-> %s: %s %s rev %s\n",
41f81d54 2482 drive->name, tape->name, vendor_id, product_id, fw_rev);
1da177e4
LT		 2483}
2484
2485/*
b6422013
BP		 2486 * Ask the tape about its various parameters. In particular, we will adjust our
2487 * data transfer buffer size to the recommended value as returned by the tape.
1da177e4 2488 */
5a04cfa9 2489static void idetape_get_mode_sense_results(ide_drive_t *drive)
1da177e4
LT		 2490{
2491 idetape_tape_t *tape = drive->driver_data;
d236d74c 2492 struct ide_atapi_pc pc;
b6422013
BP		 2493 u8 *caps;
2494 u8 speed, max_speed;
47314fa4 2495
1da177e4
LT		 2496 idetape_create_mode_sense_cmd(&pc, IDETAPE_CAPABILITIES_PAGE);
2497 if (idetape_queue_pc_tail(drive, &pc)) {
b6422013
BP		 2498 printk(KERN_ERR "ide-tape: Can't get tape parameters - assuming"
2499 " some default values\n");
54bb2074 2500 tape->blk_size = 512;
b6422013
BP		 2501 put_unaligned(52, (u16 *)&tape->caps[12]);
2502 put_unaligned(540, (u16 *)&tape->caps[14]);
2503 put_unaligned(6*52, (u16 *)&tape->caps[16]);
1da177e4
LT		 2504 return;
2505 }
d236d74c 2506 caps = pc.buf + 4 + pc.buf[3];
b6422013
BP		 2507
2508 /* convert to host order and save for later use */
2509 speed = be16_to_cpu(*(u16 *)&caps[14]);
2510 max_speed = be16_to_cpu(*(u16 *)&caps[8]);
1da177e4 2511
b6422013
BP		 2512 put_unaligned(max_speed, (u16 *)&caps[8]);
2513 put_unaligned(be16_to_cpu(*(u16 *)&caps[12]), (u16 *)&caps[12]);
2514 put_unaligned(speed, (u16 *)&caps[14]);
2515 put_unaligned(be16_to_cpu(*(u16 *)&caps[16]), (u16 *)&caps[16]);
1da177e4 2516
b6422013
BP		 2517 if (!speed) {
2518 printk(KERN_INFO "ide-tape: %s: invalid tape speed "
2519 "(assuming 650KB/sec)\n", drive->name);
2520 put_unaligned(650, (u16 *)&caps[14]);
1da177e4 2521 }
b6422013
BP		 2522 if (!max_speed) {
2523 printk(KERN_INFO "ide-tape: %s: invalid max_speed "
2524 "(assuming 650KB/sec)\n", drive->name);
2525 put_unaligned(650, (u16 *)&caps[8]);
1da177e4
LT		 2526 }
2527
b6422013
BP		 2528 memcpy(&tape->caps, caps, 20);
2529 if (caps[7] & 0x02)
54bb2074 2530 tape->blk_size = 512;
b6422013 2531 else if (caps[7] & 0x04)
54bb2074 2532 tape->blk_size = 1024;
1da177e4
LT		 2533}
2534
7662d046 2535#ifdef CONFIG_IDE_PROC_FS
5a04cfa9 2536static void idetape_add_settings(ide_drive_t *drive)
1da177e4
LT		 2537{
2538 idetape_tape_t *tape = drive->driver_data;
2539
b6422013
BP		 2540 ide_add_setting(drive, "buffer", SETTING_READ, TYPE_SHORT, 0, 0xffff,
2541 1, 2, (u16 *)&tape->caps[16], NULL);
b6422013
BP		 2542 ide_add_setting(drive, "speed", SETTING_READ, TYPE_SHORT, 0, 0xffff,
2543 1, 1, (u16 *)&tape->caps[14], NULL);
f73850a3
BP		 2544 ide_add_setting(drive, "buffer_size", SETTING_READ, TYPE_INT, 0, 0xffff,
2545 1, 1024, &tape->buffer_size, NULL);
54bb2074
BP		 2546 ide_add_setting(drive, "tdsc", SETTING_RW, TYPE_INT, IDETAPE_DSC_RW_MIN,
2547 IDETAPE_DSC_RW_MAX, 1000, HZ, &tape->best_dsc_rw_freq,
2548 NULL);
5a04cfa9
BP		 2549 ide_add_setting(drive, "dsc_overlap", SETTING_RW, TYPE_BYTE, 0, 1, 1,
2550 1, &drive->dsc_overlap, NULL);
5a04cfa9
BP		 2551 ide_add_setting(drive, "avg_speed", SETTING_READ, TYPE_INT, 0, 0xffff,
2552 1, 1, &tape->avg_speed, NULL);
8004a8c9
BP		 2553 ide_add_setting(drive, "debug_mask", SETTING_RW, TYPE_INT, 0, 0xffff, 1,
2554 1, &tape->debug_mask, NULL);
1da177e4 2555}
7662d046
BZ		 2556#else
2557static inline void idetape_add_settings(ide_drive_t *drive) { ; }
2558#endif
1da177e4
LT		 2559
2560/*
3c98bf34 2561 * The function below is called to:
1da177e4 2562 *
3c98bf34
BP		 2563 * 1. Initialize our various state variables.
2564 * 2. Ask the tape for its capabilities.
2565 * 3. Allocate a buffer which will be used for data transfer. The buffer size
2566 * is chosen based on the recommendation which we received in step 2.
1da177e4 2567 *
3c98bf34
BP		 2568 * Note that at this point ide.c already assigned us an irq, so that we can
2569 * queue requests here and wait for their completion.
1da177e4 2570 */
5a04cfa9 2571static void idetape_setup(ide_drive_t *drive, idetape_tape_t *tape, int minor)
1da177e4 2572{
83042b24 2573 unsigned long t;
1da177e4 2574 int speed;
f73850a3 2575 int buffer_size;
71071b8e 2576 u8 gcw[2];
b6422013 2577 u16 *ctl = (u16 *)&tape->caps[12];
1da177e4 2578
54bb2074 2579 spin_lock_init(&tape->lock);
1da177e4 2580 drive->dsc_overlap = 1;
4166c199
BZ		 2581 if (drive->hwif->host_flags & IDE_HFLAG_NO_DSC) {
2582 printk(KERN_INFO "ide-tape: %s: disabling DSC overlap\n",
2583 tape->name);
2584 drive->dsc_overlap = 0;
1da177e4 2585 }
1da177e4
LT		 2586 /* Seagate Travan drives do not support DSC overlap. */
2587 if (strstr(drive->id->model, "Seagate STT3401"))
2588 drive->dsc_overlap = 0;
2589 tape->minor = minor;
2590 tape->name[0] = 'h';
2591 tape->name[1] = 't';
2592 tape->name[2] = '0' + minor;
54abf37e 2593 tape->chrdev_dir = IDETAPE_DIR_NONE;
1da177e4 2594 tape->pc = tape->pc_stack;
1da177e4 2595 *((unsigned short *) &gcw) = drive->id->config;
71071b8e
BP		 2596
2597 /* Command packet DRQ type */
2598 if (((gcw[0] & 0x60) >> 5) == 1)
346331f8 2599 set_bit(IDETAPE_FLAG_DRQ_INTERRUPT, &tape->flags);
1da177e4 2600
1da177e4
LT		 2601 idetape_get_inquiry_results(drive);
2602 idetape_get_mode_sense_results(drive);
3cffb9ce 2603 ide_tape_get_bsize_from_bdesc(drive);
1da177e4 2604 tape->user_bs_factor = 1;
f73850a3
BP		 2605 tape->buffer_size = *ctl * tape->blk_size;
2606 while (tape->buffer_size > 0xffff) {
1da177e4 2607 printk(KERN_NOTICE "ide-tape: decreasing stage size\n");
b6422013 2608 *ctl /= 2;
f73850a3 2609 tape->buffer_size = *ctl * tape->blk_size;
1da177e4 2610 }
f73850a3 2611 buffer_size = tape->buffer_size;
a997a435 2612 tape->pages_per_buffer = buffer_size / PAGE_SIZE;
f73850a3 2613 if (buffer_size % PAGE_SIZE) {
a997a435 2614 tape->pages_per_buffer++;
f73850a3 2615 tape->excess_bh_size = PAGE_SIZE - buffer_size % PAGE_SIZE;
1da177e4
LT		 2616 }
2617
83042b24 2618 /* select the "best" DSC read/write polling freq */
b6422013 2619 speed = max(*(u16 *)&tape->caps[14], *(u16 *)&tape->caps[8]);
1da177e4 2620
f73850a3 2621 t = (IDETAPE_FIFO_THRESHOLD * tape->buffer_size * HZ) / (speed * 1000);
1da177e4
LT		 2622
2623 /*
3c98bf34
BP		 2624 * Ensure that the number we got makes sense; limit it within
2625 * IDETAPE_DSC_RW_MIN and IDETAPE_DSC_RW_MAX.
1da177e4 2626 */
a792bd5a
HH		 2627 tape->best_dsc_rw_freq = clamp_t(unsigned long, t, IDETAPE_DSC_RW_MIN,
2628 IDETAPE_DSC_RW_MAX);
1da177e4 2629 printk(KERN_INFO "ide-tape: %s <-> %s: %dKBps, %d*%dkB buffer, "
83042b24 2630 "%lums tDSC%s\n",
b6422013 2631 drive->name, tape->name, *(u16 *)&tape->caps[14],
f73850a3
BP		 2632 (*(u16 *)&tape->caps[16] * 512) / tape->buffer_size,
2633 tape->buffer_size / 1024,
54bb2074 2634 tape->best_dsc_rw_freq * 1000 / HZ,
1da177e4
LT		 2635 drive->using_dma ? ", DMA":"");
2636
2637 idetape_add_settings(drive);
2638}
2639
4031bbe4 2640static void ide_tape_remove(ide_drive_t *drive)
1da177e4
LT		 2641{
2642 idetape_tape_t *tape = drive->driver_data;
1da177e4 2643
7662d046 2644 ide_proc_unregister_driver(drive, tape->driver);
1da177e4
LT		 2645
2646 ide_unregister_region(tape->disk);
2647
2648 ide_tape_put(tape);
1da177e4
LT		 2649}
2650
2651static void ide_tape_release(struct kref *kref)
2652{
2653 struct ide_tape_obj *tape = to_ide_tape(kref);
2654 ide_drive_t *drive = tape->drive;
2655 struct gendisk *g = tape->disk;
2656
01a63aeb 2657 BUG_ON(tape->merge_bh_size);
8604affd 2658
1da177e4
LT		 2659 drive->dsc_overlap = 0;
2660 drive->driver_data = NULL;
dbc1272e 2661 device_destroy(idetape_sysfs_class, MKDEV(IDETAPE_MAJOR, tape->minor));
5a04cfa9
BP		 2662 device_destroy(idetape_sysfs_class,
2663 MKDEV(IDETAPE_MAJOR, tape->minor + 128));
1da177e4
LT		 2664 idetape_devs[tape->minor] = NULL;
2665 g->private_data = NULL;
2666 put_disk(g);
2667 kfree(tape);
2668}
2669
ecfd80e4 2670#ifdef CONFIG_IDE_PROC_FS
1da177e4
LT		 2671static int proc_idetape_read_name
2672 (char *page, char **start, off_t off, int count, int *eof, void *data)
2673{
2674 ide_drive_t *drive = (ide_drive_t *) data;
2675 idetape_tape_t *tape = drive->driver_data;
2676 char *out = page;
2677 int len;
2678
2679 len = sprintf(out, "%s\n", tape->name);
2680 PROC_IDE_READ_RETURN(page, start, off, count, eof, len);
2681}
2682
2683static ide_proc_entry_t idetape_proc[] = {
2684 { "capacity", S_IFREG|S_IRUGO, proc_ide_read_capacity, NULL },
2685 { "name", S_IFREG|S_IRUGO, proc_idetape_read_name, NULL },
2686 { NULL, 0, NULL, NULL }
2687};
1da177e4
LT		 2688#endif
2689
4031bbe4 2690static int ide_tape_probe(ide_drive_t *);
1da177e4 2691
1da177e4 2692static ide_driver_t idetape_driver = {
8604affd 2693 .gen_driver = {
4ef3b8f4 2694 .owner = THIS_MODULE,
8604affd
BZ		 2695 .name = "ide-tape",
2696 .bus = &ide_bus_type,
8604affd 2697 },
4031bbe4
RK		 2698 .probe = ide_tape_probe,
2699 .remove = ide_tape_remove,
1da177e4
LT		 2700 .version = IDETAPE_VERSION,
2701 .media = ide_tape,
1da177e4 2702 .supports_dsc_overlap = 1,
1da177e4
LT		 2703 .do_request = idetape_do_request,
2704 .end_request = idetape_end_request,
2705 .error = __ide_error,
2706 .abort = __ide_abort,
7662d046 2707#ifdef CONFIG_IDE_PROC_FS
1da177e4 2708 .proc = idetape_proc,
7662d046 2709#endif
1da177e4
LT		 2710};
2711
3c98bf34 2712/* Our character device supporting functions, passed to register_chrdev. */
2b8693c0 2713static const struct file_operations idetape_fops = {
1da177e4
LT		 2714 .owner = THIS_MODULE,
2715 .read = idetape_chrdev_read,
2716 .write = idetape_chrdev_write,
2717 .ioctl = idetape_chrdev_ioctl,
2718 .open = idetape_chrdev_open,
2719 .release = idetape_chrdev_release,
2720};
2721
2722static int idetape_open(struct inode *inode, struct file *filp)
2723{
2724 struct gendisk *disk = inode->i_bdev->bd_disk;
2725 struct ide_tape_obj *tape;
1da177e4 2726
5a04cfa9
BP		 2727 tape = ide_tape_get(disk);
2728 if (!tape)
1da177e4
LT		 2729 return -ENXIO;
2730
1da177e4
LT		 2731 return 0;
2732}
2733
2734static int idetape_release(struct inode *inode, struct file *filp)
2735{
2736 struct gendisk *disk = inode->i_bdev->bd_disk;
2737 struct ide_tape_obj *tape = ide_tape_g(disk);
1da177e4
LT		 2738
2739 ide_tape_put(tape);
2740
2741 return 0;
2742}
2743
2744static int idetape_ioctl(struct inode *inode, struct file *file,
2745 unsigned int cmd, unsigned long arg)
2746{
2747 struct block_device *bdev = inode->i_bdev;
2748 struct ide_tape_obj *tape = ide_tape_g(bdev->bd_disk);
2749 ide_drive_t *drive = tape->drive;
2750 int err = generic_ide_ioctl(drive, file, bdev, cmd, arg);
2751 if (err == -EINVAL)
2752 err = idetape_blkdev_ioctl(drive, cmd, arg);
2753 return err;
2754}
2755
2756static struct block_device_operations idetape_block_ops = {
2757 .owner = THIS_MODULE,
2758 .open = idetape_open,
2759 .release = idetape_release,
2760 .ioctl = idetape_ioctl,
2761};
2762
4031bbe4 2763static int ide_tape_probe(ide_drive_t *drive)
1da177e4
LT		 2764{
2765 idetape_tape_t *tape;
2766 struct gendisk *g;
2767 int minor;
2768
2769 if (!strstr("ide-tape", drive->driver_req))
2770 goto failed;
2771 if (!drive->present)
2772 goto failed;
2773 if (drive->media != ide_tape)
2774 goto failed;
5a04cfa9
BP		 2775 if (!idetape_identify_device(drive)) {
2776 printk(KERN_ERR "ide-tape: %s: not supported by this version of"
2777 " the driver\n", drive->name);
1da177e4
LT		 2778 goto failed;
2779 }
5a04cfa9 2780 tape = kzalloc(sizeof(idetape_tape_t), GFP_KERNEL);
1da177e4 2781 if (tape == NULL) {
5a04cfa9
BP		 2782 printk(KERN_ERR "ide-tape: %s: Can't allocate a tape struct\n",
2783 drive->name);
1da177e4
LT		 2784 goto failed;
2785 }
2786
2787 g = alloc_disk(1 << PARTN_BITS);
2788 if (!g)
2789 goto out_free_tape;
2790
2791 ide_init_disk(g, drive);
2792
7662d046 2793 ide_proc_register_driver(drive, &idetape_driver);
1da177e4 2794
1da177e4
LT		 2795 kref_init(&tape->kref);
2796
2797 tape->drive = drive;
2798 tape->driver = &idetape_driver;
2799 tape->disk = g;
2800
2801 g->private_data = &tape->driver;
2802
2803 drive->driver_data = tape;
2804
cf8b8975 2805 mutex_lock(&idetape_ref_mutex);
1da177e4
LT		 2806 for (minor = 0; idetape_devs[minor]; minor++)
2807 ;
2808 idetape_devs[minor] = tape;
cf8b8975 2809 mutex_unlock(&idetape_ref_mutex);
1da177e4
LT		 2810
2811 idetape_setup(drive, tape, minor);
2812
dbc1272e
TJ		 2813 device_create(idetape_sysfs_class, &drive->gendev,
2814 MKDEV(IDETAPE_MAJOR, minor), "%s", tape->name);
2815 device_create(idetape_sysfs_class, &drive->gendev,
2816 MKDEV(IDETAPE_MAJOR, minor + 128), "n%s", tape->name);
d5dee80a 2817
1da177e4
LT		 2818 g->fops = &idetape_block_ops;
2819 ide_register_region(g);
2820
2821 return 0;
8604affd 2822
1da177e4
LT		 2823out_free_tape:
2824 kfree(tape);
2825failed:
8604affd 2826 return -ENODEV;
1da177e4
LT		 2827}
2828
5a04cfa9 2829static void __exit idetape_exit(void)
1da177e4 2830{
8604affd 2831 driver_unregister(&idetape_driver.gen_driver);
d5dee80a 2832 class_destroy(idetape_sysfs_class);
1da177e4
LT		 2833 unregister_chrdev(IDETAPE_MAJOR, "ht");
2834}
2835
17514e8a 2836static int __init idetape_init(void)
1da177e4 2837{
d5dee80a
WD		 2838 int error = 1;
2839 idetape_sysfs_class = class_create(THIS_MODULE, "ide_tape");
2840 if (IS_ERR(idetape_sysfs_class)) {
2841 idetape_sysfs_class = NULL;
2842 printk(KERN_ERR "Unable to create sysfs class for ide tapes\n");
2843 error = -EBUSY;
2844 goto out;
2845 }
2846
1da177e4 2847 if (register_chrdev(IDETAPE_MAJOR, "ht", &idetape_fops)) {
5a04cfa9
BP		 2848 printk(KERN_ERR "ide-tape: Failed to register chrdev"
2849 " interface\n");
d5dee80a
WD		 2850 error = -EBUSY;
2851 goto out_free_class;
1da177e4 2852 }
d5dee80a
WD		 2853
2854 error = driver_register(&idetape_driver.gen_driver);
2855 if (error)
2856 goto out_free_driver;
2857
2858 return 0;
2859
2860out_free_driver:
2861 driver_unregister(&idetape_driver.gen_driver);
2862out_free_class:
2863 class_destroy(idetape_sysfs_class);
2864out:
2865 return error;
1da177e4
LT		 2866}
2867
263756ec 2868MODULE_ALIAS("ide:*m-tape*");
1da177e4
LT		 2869module_init(idetape_init);
2870module_exit(idetape_exit);
2871MODULE_ALIAS_CHARDEV_MAJOR(IDETAPE_MAJOR);
9c145768
BP		 2872MODULE_DESCRIPTION("ATAPI Streaming TAPE Driver");
2873MODULE_LICENSE("GPL");
Linux 6.x block layer and io_uring tree(s)