This source file includes following definitions.
- dev_is_idecd
- ide_check_atapi_device
- ide_init_pc
- ide_queue_pc_tail
- ide_do_test_unit_ready
- ide_do_start_stop
- ide_set_media_lock
- ide_create_request_sense_cmd
- ide_prep_sense
- ide_queue_sense_rq
- ide_retry_pc
- ide_cd_expiry
- ide_cd_get_xferlen
- ide_read_bcount_and_ireason
- ide_check_ireason
- ide_pc_intr
- ide_init_packet_cmd
- ide_read_ireason
- ide_wait_ireason
- ide_delayed_transfer_pc
- ide_transfer_pc
- ide_issue_pc
1
2
3
4
5
6 #include <linux/kernel.h>
7 #include <linux/cdrom.h>
8 #include <linux/delay.h>
9 #include <linux/export.h>
10 #include <linux/ide.h>
11 #include <linux/scatterlist.h>
12 #include <linux/gfp.h>
13
14 #include <scsi/scsi.h>
15
16 #define DRV_NAME "ide-atapi"
17 #define PFX DRV_NAME ": "
18
19 #ifdef DEBUG
20 #define debug_log(fmt, args...) \
21 printk(KERN_INFO "ide: " fmt, ## args)
22 #else
23 #define debug_log(fmt, args...) do {} while (0)
24 #endif
25
26 #define ATAPI_MIN_CDB_BYTES 12
27
28 static inline int dev_is_idecd(ide_drive_t *drive)
29 {
30 return drive->media == ide_cdrom || drive->media == ide_optical;
31 }
32
33
34
35
36
37 int ide_check_atapi_device(ide_drive_t *drive, const char *s)
38 {
39 u16 *id = drive->id;
40 u8 gcw[2], protocol, device_type, removable, drq_type, packet_size;
41
42 *((u16 *)&gcw) = id[ATA_ID_CONFIG];
43
44 protocol = (gcw[1] & 0xC0) >> 6;
45 device_type = gcw[1] & 0x1F;
46 removable = (gcw[0] & 0x80) >> 7;
47 drq_type = (gcw[0] & 0x60) >> 5;
48 packet_size = gcw[0] & 0x03;
49
50 #ifdef CONFIG_PPC
51
52 if (drive->media == ide_floppy && device_type == 5 &&
53 !strstr((char *)&id[ATA_ID_PROD], "CD-ROM") &&
54 strstr((char *)&id[ATA_ID_PROD], "ZIP"))
55 device_type = 0;
56 #endif
57
58 if (protocol != 2)
59 printk(KERN_ERR "%s: %s: protocol (0x%02x) is not ATAPI\n",
60 s, drive->name, protocol);
61 else if ((drive->media == ide_floppy && device_type != 0) ||
62 (drive->media == ide_tape && device_type != 1))
63 printk(KERN_ERR "%s: %s: invalid device type (0x%02x)\n",
64 s, drive->name, device_type);
65 else if (removable == 0)
66 printk(KERN_ERR "%s: %s: the removable flag is not set\n",
67 s, drive->name);
68 else if (drive->media == ide_floppy && drq_type == 3)
69 printk(KERN_ERR "%s: %s: sorry, DRQ type (0x%02x) not "
70 "supported\n", s, drive->name, drq_type);
71 else if (packet_size != 0)
72 printk(KERN_ERR "%s: %s: packet size (0x%02x) is not 12 "
73 "bytes\n", s, drive->name, packet_size);
74 else
75 return 1;
76 return 0;
77 }
78 EXPORT_SYMBOL_GPL(ide_check_atapi_device);
79
80 void ide_init_pc(struct ide_atapi_pc *pc)
81 {
82 memset(pc, 0, sizeof(*pc));
83 }
84 EXPORT_SYMBOL_GPL(ide_init_pc);
85
86
87
88
89
90 int ide_queue_pc_tail(ide_drive_t *drive, struct gendisk *disk,
91 struct ide_atapi_pc *pc, void *buf, unsigned int bufflen)
92 {
93 struct request *rq;
94 int error;
95
96 rq = blk_get_request(drive->queue, REQ_OP_DRV_IN, 0);
97 ide_req(rq)->type = ATA_PRIV_MISC;
98 ide_req(rq)->special = pc;
99
100 if (buf && bufflen) {
101 error = blk_rq_map_kern(drive->queue, rq, buf, bufflen,
102 GFP_NOIO);
103 if (error)
104 goto put_req;
105 }
106
107 memcpy(scsi_req(rq)->cmd, pc->c, 12);
108 if (drive->media == ide_tape)
109 scsi_req(rq)->cmd[13] = REQ_IDETAPE_PC1;
110 blk_execute_rq(drive->queue, disk, rq, 0);
111 error = scsi_req(rq)->result ? -EIO : 0;
112 put_req:
113 blk_put_request(rq);
114 return error;
115 }
116 EXPORT_SYMBOL_GPL(ide_queue_pc_tail);
117
118 int ide_do_test_unit_ready(ide_drive_t *drive, struct gendisk *disk)
119 {
120 struct ide_atapi_pc pc;
121
122 ide_init_pc(&pc);
123 pc.c[0] = TEST_UNIT_READY;
124
125 return ide_queue_pc_tail(drive, disk, &pc, NULL, 0);
126 }
127 EXPORT_SYMBOL_GPL(ide_do_test_unit_ready);
128
129 int ide_do_start_stop(ide_drive_t *drive, struct gendisk *disk, int start)
130 {
131 struct ide_atapi_pc pc;
132
133 ide_init_pc(&pc);
134 pc.c[0] = START_STOP;
135 pc.c[4] = start;
136
137 if (drive->media == ide_tape)
138 pc.flags |= PC_FLAG_WAIT_FOR_DSC;
139
140 return ide_queue_pc_tail(drive, disk, &pc, NULL, 0);
141 }
142 EXPORT_SYMBOL_GPL(ide_do_start_stop);
143
144 int ide_set_media_lock(ide_drive_t *drive, struct gendisk *disk, int on)
145 {
146 struct ide_atapi_pc pc;
147
148 if ((drive->dev_flags & IDE_DFLAG_DOORLOCKING) == 0)
149 return 0;
150
151 ide_init_pc(&pc);
152 pc.c[0] = ALLOW_MEDIUM_REMOVAL;
153 pc.c[4] = on;
154
155 return ide_queue_pc_tail(drive, disk, &pc, NULL, 0);
156 }
157 EXPORT_SYMBOL_GPL(ide_set_media_lock);
158
159 void ide_create_request_sense_cmd(ide_drive_t *drive, struct ide_atapi_pc *pc)
160 {
161 ide_init_pc(pc);
162 pc->c[0] = REQUEST_SENSE;
163 if (drive->media == ide_floppy) {
164 pc->c[4] = 255;
165 pc->req_xfer = 18;
166 } else {
167 pc->c[4] = 20;
168 pc->req_xfer = 20;
169 }
170 }
171 EXPORT_SYMBOL_GPL(ide_create_request_sense_cmd);
172
173 void ide_prep_sense(ide_drive_t *drive, struct request *rq)
174 {
175 struct request_sense *sense = &drive->sense_data;
176 struct request *sense_rq;
177 struct scsi_request *req;
178 unsigned int cmd_len, sense_len;
179 int err;
180
181 switch (drive->media) {
182 case ide_floppy:
183 cmd_len = 255;
184 sense_len = 18;
185 break;
186 case ide_tape:
187 cmd_len = 20;
188 sense_len = 20;
189 break;
190 default:
191 cmd_len = 18;
192 sense_len = 18;
193 }
194
195 BUG_ON(sense_len > sizeof(*sense));
196
197 if (ata_sense_request(rq) || drive->sense_rq_armed)
198 return;
199
200 sense_rq = drive->sense_rq;
201 if (!sense_rq) {
202 sense_rq = blk_mq_alloc_request(drive->queue, REQ_OP_DRV_IN,
203 BLK_MQ_REQ_RESERVED | BLK_MQ_REQ_NOWAIT);
204 drive->sense_rq = sense_rq;
205 }
206 req = scsi_req(sense_rq);
207
208 memset(sense, 0, sizeof(*sense));
209
210 scsi_req_init(req);
211
212 err = blk_rq_map_kern(drive->queue, sense_rq, sense, sense_len,
213 GFP_NOIO);
214 if (unlikely(err)) {
215 if (printk_ratelimit())
216 printk(KERN_WARNING PFX "%s: failed to map sense "
217 "buffer\n", drive->name);
218 blk_mq_free_request(sense_rq);
219 drive->sense_rq = NULL;
220 return;
221 }
222
223 sense_rq->rq_disk = rq->rq_disk;
224 sense_rq->cmd_flags = REQ_OP_DRV_IN;
225 ide_req(sense_rq)->type = ATA_PRIV_SENSE;
226 sense_rq->rq_flags |= RQF_PREEMPT;
227
228 req->cmd[0] = GPCMD_REQUEST_SENSE;
229 req->cmd[4] = cmd_len;
230 if (drive->media == ide_tape)
231 req->cmd[13] = REQ_IDETAPE_PC1;
232
233 drive->sense_rq_armed = true;
234 }
235 EXPORT_SYMBOL_GPL(ide_prep_sense);
236
237 int ide_queue_sense_rq(ide_drive_t *drive, void *special)
238 {
239 ide_hwif_t *hwif = drive->hwif;
240 struct request *sense_rq;
241 unsigned long flags;
242
243 spin_lock_irqsave(&hwif->lock, flags);
244
245
246 if (!drive->sense_rq_armed) {
247 printk(KERN_WARNING PFX "%s: error queuing a sense request\n",
248 drive->name);
249 spin_unlock_irqrestore(&hwif->lock, flags);
250 return -ENOMEM;
251 }
252
253 sense_rq = drive->sense_rq;
254 ide_req(sense_rq)->special = special;
255 drive->sense_rq_armed = false;
256
257 drive->hwif->rq = NULL;
258
259 ide_insert_request_head(drive, sense_rq);
260 spin_unlock_irqrestore(&hwif->lock, flags);
261 return 0;
262 }
263 EXPORT_SYMBOL_GPL(ide_queue_sense_rq);
264
265
266
267
268
269
270 void ide_retry_pc(ide_drive_t *drive)
271 {
272 struct request *failed_rq = drive->hwif->rq;
273 struct request *sense_rq = drive->sense_rq;
274 struct ide_atapi_pc *pc = &drive->request_sense_pc;
275
276 (void)ide_read_error(drive);
277
278
279 ide_init_pc(pc);
280 memcpy(pc->c, scsi_req(sense_rq)->cmd, 12);
281
282 if (drive->media == ide_tape)
283 drive->atapi_flags |= IDE_AFLAG_IGNORE_DSC;
284
285
286
287
288
289
290 drive->hwif->rq = NULL;
291 ide_requeue_and_plug(drive, failed_rq);
292 if (ide_queue_sense_rq(drive, pc))
293 ide_complete_rq(drive, BLK_STS_IOERR, blk_rq_bytes(failed_rq));
294 }
295 EXPORT_SYMBOL_GPL(ide_retry_pc);
296
297 int ide_cd_expiry(ide_drive_t *drive)
298 {
299 struct request *rq = drive->hwif->rq;
300 unsigned long wait = 0;
301
302 debug_log("%s: scsi_req(rq)->cmd[0]: 0x%x\n", __func__, scsi_req(rq)->cmd[0]);
303
304
305
306
307
308
309
310 switch (scsi_req(rq)->cmd[0]) {
311 case GPCMD_BLANK:
312 case GPCMD_FORMAT_UNIT:
313 case GPCMD_RESERVE_RZONE_TRACK:
314 case GPCMD_CLOSE_TRACK:
315 case GPCMD_FLUSH_CACHE:
316 wait = ATAPI_WAIT_PC;
317 break;
318 default:
319 if (!(rq->rq_flags & RQF_QUIET))
320 printk(KERN_INFO PFX "cmd 0x%x timed out\n",
321 scsi_req(rq)->cmd[0]);
322 wait = 0;
323 break;
324 }
325 return wait;
326 }
327 EXPORT_SYMBOL_GPL(ide_cd_expiry);
328
329 int ide_cd_get_xferlen(struct request *rq)
330 {
331 switch (req_op(rq)) {
332 default:
333 return 32768;
334 case REQ_OP_SCSI_IN:
335 case REQ_OP_SCSI_OUT:
336 return blk_rq_bytes(rq);
337 case REQ_OP_DRV_IN:
338 case REQ_OP_DRV_OUT:
339 switch (ide_req(rq)->type) {
340 case ATA_PRIV_PC:
341 case ATA_PRIV_SENSE:
342 return blk_rq_bytes(rq);
343 default:
344 return 0;
345 }
346 }
347 }
348 EXPORT_SYMBOL_GPL(ide_cd_get_xferlen);
349
350 void ide_read_bcount_and_ireason(ide_drive_t *drive, u16 *bcount, u8 *ireason)
351 {
352 struct ide_taskfile tf;
353
354 drive->hwif->tp_ops->tf_read(drive, &tf, IDE_VALID_NSECT |
355 IDE_VALID_LBAM | IDE_VALID_LBAH);
356
357 *bcount = (tf.lbah << 8) | tf.lbam;
358 *ireason = tf.nsect & 3;
359 }
360 EXPORT_SYMBOL_GPL(ide_read_bcount_and_ireason);
361
362
363
364
365
366
367
368
369
370 int ide_check_ireason(ide_drive_t *drive, struct request *rq, int len,
371 int ireason, int rw)
372 {
373 ide_hwif_t *hwif = drive->hwif;
374
375 debug_log("ireason: 0x%x, rw: 0x%x\n", ireason, rw);
376
377 if (ireason == (!rw << 1))
378 return 0;
379 else if (ireason == (rw << 1)) {
380 printk(KERN_ERR PFX "%s: %s: wrong transfer direction!\n",
381 drive->name, __func__);
382
383 if (dev_is_idecd(drive))
384 ide_pad_transfer(drive, rw, len);
385 } else if (!rw && ireason == ATAPI_COD) {
386 if (dev_is_idecd(drive)) {
387
388
389
390
391 (void)hwif->tp_ops->read_status(hwif);
392 return 0;
393 }
394 } else {
395 if (ireason & ATAPI_COD)
396 printk(KERN_ERR PFX "%s: CoD != 0 in %s\n", drive->name,
397 __func__);
398
399
400 printk(KERN_ERR PFX "%s: %s: bad interrupt reason 0x%02x\n",
401 drive->name, __func__, ireason);
402 }
403
404 if (dev_is_idecd(drive) && ata_pc_request(rq))
405 rq->rq_flags |= RQF_FAILED;
406
407 return 1;
408 }
409 EXPORT_SYMBOL_GPL(ide_check_ireason);
410
411
412
413
414
415
416 static ide_startstop_t ide_pc_intr(ide_drive_t *drive)
417 {
418 struct ide_atapi_pc *pc = drive->pc;
419 ide_hwif_t *hwif = drive->hwif;
420 struct ide_cmd *cmd = &hwif->cmd;
421 struct request *rq = hwif->rq;
422 const struct ide_tp_ops *tp_ops = hwif->tp_ops;
423 unsigned int timeout, done;
424 u16 bcount;
425 u8 stat, ireason, dsc = 0;
426 u8 write = !!(pc->flags & PC_FLAG_WRITING);
427
428 debug_log("Enter %s - interrupt handler\n", __func__);
429
430 timeout = (drive->media == ide_floppy) ? WAIT_FLOPPY_CMD
431 : WAIT_TAPE_CMD;
432
433
434 stat = tp_ops->read_status(hwif);
435
436 if (pc->flags & PC_FLAG_DMA_IN_PROGRESS) {
437 int rc;
438
439 drive->waiting_for_dma = 0;
440 rc = hwif->dma_ops->dma_end(drive);
441 ide_dma_unmap_sg(drive, cmd);
442
443 if (rc || (drive->media == ide_tape && (stat & ATA_ERR))) {
444 if (drive->media == ide_floppy)
445 printk(KERN_ERR PFX "%s: DMA %s error\n",
446 drive->name, rq_data_dir(pc->rq)
447 ? "write" : "read");
448 pc->flags |= PC_FLAG_DMA_ERROR;
449 } else
450 scsi_req(rq)->resid_len = 0;
451 debug_log("%s: DMA finished\n", drive->name);
452 }
453
454
455 if ((stat & ATA_DRQ) == 0) {
456 int uptodate;
457 blk_status_t error;
458
459 debug_log("Packet command completed, %d bytes transferred\n",
460 blk_rq_bytes(rq));
461
462 pc->flags &= ~PC_FLAG_DMA_IN_PROGRESS;
463
464 local_irq_enable_in_hardirq();
465
466 if (drive->media == ide_tape &&
467 (stat & ATA_ERR) && scsi_req(rq)->cmd[0] == REQUEST_SENSE)
468 stat &= ~ATA_ERR;
469
470 if ((stat & ATA_ERR) || (pc->flags & PC_FLAG_DMA_ERROR)) {
471
472 debug_log("%s: I/O error\n", drive->name);
473
474 if (drive->media != ide_tape)
475 scsi_req(pc->rq)->result++;
476
477 if (scsi_req(rq)->cmd[0] == REQUEST_SENSE) {
478 printk(KERN_ERR PFX "%s: I/O error in request "
479 "sense command\n", drive->name);
480 return ide_do_reset(drive);
481 }
482
483 debug_log("[cmd %x]: check condition\n", scsi_req(rq)->cmd[0]);
484
485
486 ide_retry_pc(drive);
487
488
489 return ide_stopped;
490 }
491 pc->error = 0;
492
493 if ((pc->flags & PC_FLAG_WAIT_FOR_DSC) && (stat & ATA_DSC) == 0)
494 dsc = 1;
495
496
497
498
499
500 done = blk_rq_bytes(rq);
501
502
503 uptodate = drive->pc_callback(drive, dsc);
504
505 if (uptodate == 0)
506 drive->failed_pc = NULL;
507
508 if (ata_misc_request(rq)) {
509 scsi_req(rq)->result = 0;
510 error = BLK_STS_OK;
511 } else {
512
513 if (blk_rq_is_passthrough(rq) && uptodate <= 0) {
514 if (scsi_req(rq)->result == 0)
515 scsi_req(rq)->result = -EIO;
516 }
517
518 error = uptodate ? BLK_STS_OK : BLK_STS_IOERR;
519 }
520
521 ide_complete_rq(drive, error, blk_rq_bytes(rq));
522 return ide_stopped;
523 }
524
525 if (pc->flags & PC_FLAG_DMA_IN_PROGRESS) {
526 pc->flags &= ~PC_FLAG_DMA_IN_PROGRESS;
527 printk(KERN_ERR PFX "%s: The device wants to issue more "
528 "interrupts in DMA mode\n", drive->name);
529 ide_dma_off(drive);
530 return ide_do_reset(drive);
531 }
532
533
534 ide_read_bcount_and_ireason(drive, &bcount, &ireason);
535
536 if (ide_check_ireason(drive, rq, bcount, ireason, write))
537 return ide_do_reset(drive);
538
539 done = min_t(unsigned int, bcount, cmd->nleft);
540 ide_pio_bytes(drive, cmd, write, done);
541
542
543 scsi_req(rq)->resid_len -= done;
544
545 bcount -= done;
546
547 if (bcount)
548 ide_pad_transfer(drive, write, bcount);
549
550 debug_log("[cmd %x] transferred %d bytes, padded %d bytes, resid: %u\n",
551 scsi_req(rq)->cmd[0], done, bcount, scsi_req(rq)->resid_len);
552
553
554 ide_set_handler(drive, ide_pc_intr, timeout);
555 return ide_started;
556 }
557
558 static void ide_init_packet_cmd(struct ide_cmd *cmd, u8 valid_tf,
559 u16 bcount, u8 dma)
560 {
561 cmd->protocol = dma ? ATAPI_PROT_DMA : ATAPI_PROT_PIO;
562 cmd->valid.out.tf = IDE_VALID_LBAH | IDE_VALID_LBAM |
563 IDE_VALID_FEATURE | valid_tf;
564 cmd->tf.command = ATA_CMD_PACKET;
565 cmd->tf.feature = dma;
566 cmd->tf.lbam = bcount & 0xff;
567 cmd->tf.lbah = (bcount >> 8) & 0xff;
568 }
569
570 static u8 ide_read_ireason(ide_drive_t *drive)
571 {
572 struct ide_taskfile tf;
573
574 drive->hwif->tp_ops->tf_read(drive, &tf, IDE_VALID_NSECT);
575
576 return tf.nsect & 3;
577 }
578
579 static u8 ide_wait_ireason(ide_drive_t *drive, u8 ireason)
580 {
581 int retries = 100;
582
583 while (retries-- && ((ireason & ATAPI_COD) == 0 ||
584 (ireason & ATAPI_IO))) {
585 printk(KERN_ERR PFX "%s: (IO,CoD != (0,1) while issuing "
586 "a packet command, retrying\n", drive->name);
587 udelay(100);
588 ireason = ide_read_ireason(drive);
589 if (retries == 0) {
590 printk(KERN_ERR PFX "%s: (IO,CoD != (0,1) while issuing"
591 " a packet command, ignoring\n",
592 drive->name);
593 ireason |= ATAPI_COD;
594 ireason &= ~ATAPI_IO;
595 }
596 }
597
598 return ireason;
599 }
600
601 static int ide_delayed_transfer_pc(ide_drive_t *drive)
602 {
603
604 drive->hwif->tp_ops->output_data(drive, NULL, drive->pc->c, 12);
605
606
607 return WAIT_FLOPPY_CMD;
608 }
609
610 static ide_startstop_t ide_transfer_pc(ide_drive_t *drive)
611 {
612 struct ide_atapi_pc *uninitialized_var(pc);
613 ide_hwif_t *hwif = drive->hwif;
614 struct request *rq = hwif->rq;
615 ide_expiry_t *expiry;
616 unsigned int timeout;
617 int cmd_len;
618 ide_startstop_t startstop;
619 u8 ireason;
620
621 if (ide_wait_stat(&startstop, drive, ATA_DRQ, ATA_BUSY, WAIT_READY)) {
622 printk(KERN_ERR PFX "%s: Strange, packet command initiated yet "
623 "DRQ isn't asserted\n", drive->name);
624 return startstop;
625 }
626
627 if (drive->atapi_flags & IDE_AFLAG_DRQ_INTERRUPT) {
628 if (drive->dma)
629 drive->waiting_for_dma = 1;
630 }
631
632 if (dev_is_idecd(drive)) {
633
634 cmd_len = COMMAND_SIZE(scsi_req(rq)->cmd[0]);
635 if (cmd_len < ATAPI_MIN_CDB_BYTES)
636 cmd_len = ATAPI_MIN_CDB_BYTES;
637
638 timeout = rq->timeout;
639 expiry = ide_cd_expiry;
640 } else {
641 pc = drive->pc;
642
643 cmd_len = ATAPI_MIN_CDB_BYTES;
644
645
646
647
648
649
650 if (drive->atapi_flags & IDE_AFLAG_ZIP_DRIVE) {
651 timeout = drive->pc_delay;
652 expiry = &ide_delayed_transfer_pc;
653 } else {
654 timeout = (drive->media == ide_floppy) ? WAIT_FLOPPY_CMD
655 : WAIT_TAPE_CMD;
656 expiry = NULL;
657 }
658
659 ireason = ide_read_ireason(drive);
660 if (drive->media == ide_tape)
661 ireason = ide_wait_ireason(drive, ireason);
662
663 if ((ireason & ATAPI_COD) == 0 || (ireason & ATAPI_IO)) {
664 printk(KERN_ERR PFX "%s: (IO,CoD) != (0,1) while "
665 "issuing a packet command\n", drive->name);
666
667 return ide_do_reset(drive);
668 }
669 }
670
671 hwif->expiry = expiry;
672
673
674 ide_set_handler(drive,
675 (dev_is_idecd(drive) ? drive->irq_handler
676 : ide_pc_intr),
677 timeout);
678
679
680 if ((drive->atapi_flags & IDE_AFLAG_ZIP_DRIVE) == 0)
681 hwif->tp_ops->output_data(drive, NULL, scsi_req(rq)->cmd, cmd_len);
682
683
684 if (dev_is_idecd(drive)) {
685 if (drive->dma)
686 hwif->dma_ops->dma_start(drive);
687 } else {
688 if (pc->flags & PC_FLAG_DMA_OK) {
689 pc->flags |= PC_FLAG_DMA_IN_PROGRESS;
690 hwif->dma_ops->dma_start(drive);
691 }
692 }
693
694 return ide_started;
695 }
696
697 ide_startstop_t ide_issue_pc(ide_drive_t *drive, struct ide_cmd *cmd)
698 {
699 struct ide_atapi_pc *pc;
700 ide_hwif_t *hwif = drive->hwif;
701 ide_expiry_t *expiry = NULL;
702 struct request *rq = hwif->rq;
703 unsigned int timeout, bytes;
704 u16 bcount;
705 u8 valid_tf;
706 u8 drq_int = !!(drive->atapi_flags & IDE_AFLAG_DRQ_INTERRUPT);
707
708 if (dev_is_idecd(drive)) {
709 valid_tf = IDE_VALID_NSECT | IDE_VALID_LBAL;
710 bcount = ide_cd_get_xferlen(rq);
711 expiry = ide_cd_expiry;
712 timeout = ATAPI_WAIT_PC;
713
714 if (drive->dma)
715 drive->dma = !ide_dma_prepare(drive, cmd);
716 } else {
717 pc = drive->pc;
718
719 valid_tf = IDE_VALID_DEVICE;
720 bytes = blk_rq_bytes(rq);
721 bcount = ((drive->media == ide_tape) ? bytes
722 : min_t(unsigned int,
723 bytes, 63 * 1024));
724
725
726 scsi_req(rq)->resid_len = bcount;
727
728 if (pc->flags & PC_FLAG_DMA_ERROR) {
729 pc->flags &= ~PC_FLAG_DMA_ERROR;
730 ide_dma_off(drive);
731 }
732
733 if (pc->flags & PC_FLAG_DMA_OK)
734 drive->dma = !ide_dma_prepare(drive, cmd);
735
736 if (!drive->dma)
737 pc->flags &= ~PC_FLAG_DMA_OK;
738
739 timeout = (drive->media == ide_floppy) ? WAIT_FLOPPY_CMD
740 : WAIT_TAPE_CMD;
741 }
742
743 ide_init_packet_cmd(cmd, valid_tf, bcount, drive->dma);
744
745 (void)do_rw_taskfile(drive, cmd);
746
747 if (drq_int) {
748 if (drive->dma)
749 drive->waiting_for_dma = 0;
750 hwif->expiry = expiry;
751 }
752
753 ide_execute_command(drive, cmd, ide_transfer_pc, timeout);
754
755 return drq_int ? ide_started : ide_transfer_pc(drive);
756 }
757 EXPORT_SYMBOL_GPL(ide_issue_pc);