2 * IDE ATAPI streaming tape driver.
4 * Copyright (C) 1995-1999 Gadi Oxman <gadio@netvision.net.il>
5 * Copyright (C) 2003-2005 Bartlomiej Zolnierkiewicz
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.
11 * It is hereby placed under the terms of the GNU general public license.
12 * (See linux/COPYING).
14 * For a historical changelog see
15 * Documentation/ide/ChangeLog.ide-tape.1995-2002
18 #define IDETAPE_VERSION "1.20"
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>
27 #include <linux/interrupt.h>
28 #include <linux/jiffies.h>
29 #include <linux/major.h>
30 #include <linux/errno.h>
31 #include <linux/genhd.h>
32 #include <linux/slab.h>
33 #include <linux/pci.h>
34 #include <linux/ide.h>
35 #include <linux/smp_lock.h>
36 #include <linux/completion.h>
37 #include <linux/bitops.h>
38 #include <linux/mutex.h>
39 #include <scsi/scsi.h>
41 #include <asm/byteorder.h>
42 #include <linux/irq.h>
43 #include <linux/uaccess.h>
45 #include <asm/unaligned.h>
46 #include <linux/mtio.h>
49 /* output errors only */
51 /* output all sense key/asc */
53 /* info regarding all chrdev-related procedures */
54 DBG_CHRDEV = (1 << 2),
55 /* all remaining procedures */
57 /* buffer alloc info (pc_stack & rq_stack) */
58 DBG_PCRQ_STACK = (1 << 4),
61 /* define to see debug info */
62 #define IDETAPE_DEBUG_LOG 0
65 #define debug_log(lvl, fmt, args...) \
67 if (tape->debug_mask & lvl) \
68 printk(KERN_INFO "ide-tape: " fmt, ## args); \
71 #define debug_log(lvl, fmt, args...) do {} while (0)
74 /**************************** Tunable parameters *****************************/
76 * After each failed packet command we issue a request sense command and retry
77 * the packet command IDETAPE_MAX_PC_RETRIES times.
79 * Setting IDETAPE_MAX_PC_RETRIES to 0 will disable retries.
81 #define IDETAPE_MAX_PC_RETRIES 3
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)
87 #define IDETAPE_PC_BUFFER_SIZE 256
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.
94 #define IDETAPE_PC_STACK (10 + IDETAPE_MAX_PC_RETRIES)
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).
101 #define IDETAPE_WAIT_CMD (900*HZ)
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.
109 #define IDETAPE_FIFO_THRESHOLD 2
112 * DSC polling parameters.
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:
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.
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).
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.
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 */
145 /*************************** End of tunable parameters ***********************/
147 /* tape directions */
149 IDETAPE_DIR_NONE = (1 << 0),
150 IDETAPE_DIR_READ = (1 << 1),
151 IDETAPE_DIR_WRITE = (1 << 2),
157 struct idetape_bh *b_reqnext;
161 /* Tape door status */
162 #define DOOR_UNLOCKED 0
163 #define DOOR_LOCKED 1
164 #define DOOR_EXPLICITLY_LOCKED 2
166 /* Some defines for the SPACE command */
167 #define IDETAPE_SPACE_OVER_FILEMARK 1
168 #define IDETAPE_SPACE_TO_EOD 3
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
176 * Special requests for our block device strategy routine.
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.
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),
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
194 /* Structures related to the SELECT SENSE / MODE SENSE packet commands. */
195 #define IDETAPE_BLOCK_DESCRIPTOR 0
196 #define IDETAPE_CAPABILITIES_PAGE 0x2a
198 /* Tape flag bits values. */
200 IDETAPE_FLAG_IGNORE_DSC = (1 << 0),
201 /* 0 When the tape position is unknown */
202 IDETAPE_FLAG_ADDRESS_VALID = (1 << 1),
203 /* Device already opened */
204 IDETAPE_FLAG_BUSY = (1 << 2),
205 /* Attempt to auto-detect the current user block size */
206 IDETAPE_FLAG_DETECT_BS = (1 << 3),
207 /* Currently on a filemark */
208 IDETAPE_FLAG_FILEMARK = (1 << 4),
209 /* DRQ interrupt device */
210 IDETAPE_FLAG_DRQ_INTERRUPT = (1 << 5),
211 /* 0 = no tape is loaded, so we don't rewind after ejecting */
212 IDETAPE_FLAG_MEDIUM_PRESENT = (1 << 6),
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.
219 typedef struct ide_tape_obj {
221 ide_driver_t *driver;
222 struct gendisk *disk;
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.
233 * pc points to the current processed packet command.
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.
240 /* Current packet command */
241 struct ide_atapi_pc *pc;
242 /* Last failed packet command */
243 struct ide_atapi_pc *failed_pc;
244 /* Packet command stack */
245 struct ide_atapi_pc pc_stack[IDETAPE_PC_STACK];
246 /* Next free packet command storage space */
248 struct request rq_stack[IDETAPE_PC_STACK];
249 /* We implement a circular array */
253 * DSC polling variables.
255 * While polling for DSC we use postponed_rq to postpone the current
256 * request so that ide.c will be able to service pending requests on the
257 * other device. Note that at most we will have only one DSC (usually
258 * data transfer) request in the device request queue.
260 struct request *postponed_rq;
261 /* The time in which we started polling for DSC */
262 unsigned long dsc_polling_start;
263 /* Timer used to poll for dsc */
264 struct timer_list dsc_timer;
265 /* Read/Write dsc polling frequency */
266 unsigned long best_dsc_rw_freq;
267 unsigned long dsc_poll_freq;
268 unsigned long dsc_timeout;
270 /* Read position information */
273 unsigned int first_frame;
275 /* Last error information */
276 u8 sense_key, asc, ascq;
278 /* Character device operation */
282 /* Current character device data transfer direction */
285 /* tape block size, usually 512 or 1024 bytes */
286 unsigned short blk_size;
289 /* Copy of the tape's Capabilities and Mechanical Page */
293 * Active data transfer request parameters.
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.
300 /* Data buffer size chosen based on the tape's recommendation */
303 struct idetape_bh *merge_bh;
304 /* size of the merge buffer */
306 /* pointer to current buffer head within the merge buffer */
307 struct idetape_bh *bh;
311 int pages_per_buffer;
312 /* Wasted space in each stage */
315 /* Status/Action flags: long for set_bit */
317 /* protects the ide-tape queue */
320 /* Measures average tape speed */
321 unsigned long avg_time;
325 /* the door is currently locked */
327 /* the tape hardware is write protected */
329 /* the tape is write protected (hardware or opened as read-only) */
335 static DEFINE_MUTEX(idetape_ref_mutex);
337 static struct class *idetape_sysfs_class;
339 #define to_ide_tape(obj) container_of(obj, struct ide_tape_obj, kref)
341 #define ide_tape_g(disk) \
342 container_of((disk)->private_data, struct ide_tape_obj, driver)
344 static struct ide_tape_obj *ide_tape_get(struct gendisk *disk)
346 struct ide_tape_obj *tape = NULL;
348 mutex_lock(&idetape_ref_mutex);
349 tape = ide_tape_g(disk);
351 kref_get(&tape->kref);
352 mutex_unlock(&idetape_ref_mutex);
356 static void ide_tape_release(struct kref *);
358 static void ide_tape_put(struct ide_tape_obj *tape)
360 mutex_lock(&idetape_ref_mutex);
361 kref_put(&tape->kref, ide_tape_release);
362 mutex_unlock(&idetape_ref_mutex);
366 * The variables below are used for the character device interface. Additional
367 * state variables are defined in our ide_drive_t structure.
369 static struct ide_tape_obj *idetape_devs[MAX_HWIFS * MAX_DRIVES];
371 #define ide_tape_f(file) ((file)->private_data)
373 static struct ide_tape_obj *ide_tape_chrdev_get(unsigned int i)
375 struct ide_tape_obj *tape = NULL;
377 mutex_lock(&idetape_ref_mutex);
378 tape = idetape_devs[i];
380 kref_get(&tape->kref);
381 mutex_unlock(&idetape_ref_mutex);
385 static void idetape_input_buffers(ide_drive_t *drive, struct ide_atapi_pc *pc,
388 struct idetape_bh *bh = pc->bh;
393 printk(KERN_ERR "ide-tape: bh == NULL in "
394 "idetape_input_buffers\n");
395 ide_pad_transfer(drive, 0, bcount);
399 (unsigned int)(bh->b_size - atomic_read(&bh->b_count)),
401 drive->hwif->tp_ops->input_data(drive, NULL, bh->b_data +
402 atomic_read(&bh->b_count), count);
404 atomic_add(count, &bh->b_count);
405 if (atomic_read(&bh->b_count) == bh->b_size) {
408 atomic_set(&bh->b_count, 0);
414 static void idetape_output_buffers(ide_drive_t *drive, struct ide_atapi_pc *pc,
417 struct idetape_bh *bh = pc->bh;
422 printk(KERN_ERR "ide-tape: bh == NULL in %s\n",
426 count = min((unsigned int)pc->b_count, (unsigned int)bcount);
427 drive->hwif->tp_ops->output_data(drive, NULL, pc->b_data, count);
430 pc->b_count -= count;
435 pc->b_data = bh->b_data;
436 pc->b_count = atomic_read(&bh->b_count);
442 static void idetape_update_buffers(ide_drive_t *drive, struct ide_atapi_pc *pc)
444 struct idetape_bh *bh = pc->bh;
446 unsigned int bcount = pc->xferred;
448 if (pc->flags & PC_FLAG_WRITING)
452 printk(KERN_ERR "ide-tape: bh == NULL in %s\n",
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)
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.
471 static struct ide_atapi_pc *idetape_next_pc_storage(ide_drive_t *drive)
473 idetape_tape_t *tape = drive->driver_data;
475 debug_log(DBG_PCRQ_STACK, "pc_stack_index=%d\n", tape->pc_stack_index);
477 if (tape->pc_stack_index == IDETAPE_PC_STACK)
478 tape->pc_stack_index = 0;
479 return (&tape->pc_stack[tape->pc_stack_index++]);
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.
488 /**************************************************************
490 * This should get fixed to use kmalloc(.., GFP_ATOMIC) *
491 * followed later on by kfree(). -ml *
493 **************************************************************/
495 static struct request *idetape_next_rq_storage(ide_drive_t *drive)
497 idetape_tape_t *tape = drive->driver_data;
499 debug_log(DBG_PCRQ_STACK, "rq_stack_index=%d\n", tape->rq_stack_index);
501 if (tape->rq_stack_index == IDETAPE_PC_STACK)
502 tape->rq_stack_index = 0;
503 return (&tape->rq_stack[tape->rq_stack_index++]);
507 * called on each failed packet command retry to analyze the request sense. We
508 * currently do not utilize this information.
510 static void idetape_analyze_error(ide_drive_t *drive, u8 *sense)
512 idetape_tape_t *tape = drive->driver_data;
513 struct ide_atapi_pc *pc = tape->failed_pc;
515 tape->sense_key = sense[2] & 0xF;
516 tape->asc = sense[12];
517 tape->ascq = sense[13];
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);
522 /* Correct pc->xferred by asking the tape. */
523 if (pc->flags & PC_FLAG_DMA_ERROR) {
524 pc->xferred = pc->req_xfer -
526 get_unaligned_be32(&sense[3]);
527 idetape_update_buffers(drive, pc);
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.
535 if ((pc->c[0] == READ_6 || pc->c[0] == WRITE_6)
537 && pc->c[4] == 0 && pc->c[3] == 0 && pc->c[2] == 0) {
538 if (tape->sense_key == 5) {
539 /* don't report an error, everything's ok */
541 /* don't retry read/write */
542 pc->flags |= PC_FLAG_ABORT;
545 if (pc->c[0] == READ_6 && (sense[2] & 0x80)) {
546 pc->error = IDETAPE_ERROR_FILEMARK;
547 pc->flags |= PC_FLAG_ABORT;
549 if (pc->c[0] == WRITE_6) {
550 if ((sense[2] & 0x40) || (tape->sense_key == 0xd
551 && tape->asc == 0x0 && tape->ascq == 0x2)) {
552 pc->error = IDETAPE_ERROR_EOD;
553 pc->flags |= PC_FLAG_ABORT;
556 if (pc->c[0] == READ_6 || pc->c[0] == WRITE_6) {
557 if (tape->sense_key == 8) {
558 pc->error = IDETAPE_ERROR_EOD;
559 pc->flags |= PC_FLAG_ABORT;
561 if (!(pc->flags & PC_FLAG_ABORT) &&
563 pc->retries = IDETAPE_MAX_PC_RETRIES + 1;
567 /* Free data buffers completely. */
568 static void ide_tape_kfree_buffer(idetape_tape_t *tape)
570 struct idetape_bh *prev_bh, *bh = tape->merge_bh;
573 u32 size = bh->b_size;
576 unsigned int order = fls(size >> PAGE_SHIFT)-1;
579 free_pages((unsigned long)bh->b_data, order);
582 bh->b_data += (1 << order) * PAGE_SIZE;
590 static int idetape_end_request(ide_drive_t *drive, int uptodate, int nr_sects)
592 struct request *rq = HWGROUP(drive)->rq;
593 idetape_tape_t *tape = drive->driver_data;
597 debug_log(DBG_PROCS, "Enter %s\n", __func__);
600 case 0: error = IDETAPE_ERROR_GENERAL; break;
601 case 1: error = 0; break;
602 default: error = uptodate;
606 tape->failed_pc = NULL;
608 if (!blk_special_request(rq)) {
609 ide_end_request(drive, uptodate, nr_sects);
613 spin_lock_irqsave(&tape->lock, flags);
615 ide_end_drive_cmd(drive, 0, 0);
617 spin_unlock_irqrestore(&tape->lock, flags);
621 static void ide_tape_callback(ide_drive_t *drive)
623 idetape_tape_t *tape = drive->driver_data;
624 struct ide_atapi_pc *pc = tape->pc;
625 int uptodate = pc->error ? 0 : 1;
627 debug_log(DBG_PROCS, "Enter %s\n", __func__);
629 if (tape->failed_pc == pc)
630 tape->failed_pc = NULL;
632 if (pc->c[0] == REQUEST_SENSE) {
634 idetape_analyze_error(drive, pc->buf);
636 printk(KERN_ERR "ide-tape: Error in REQUEST SENSE "
637 "itself - Aborting request!\n");
638 } else if (pc->c[0] == READ_6 || pc->c[0] == WRITE_6) {
639 struct request *rq = drive->hwif->hwgroup->rq;
640 int blocks = pc->xferred / tape->blk_size;
642 tape->avg_size += blocks * tape->blk_size;
644 if (time_after_eq(jiffies, tape->avg_time + HZ)) {
645 tape->avg_speed = tape->avg_size * HZ /
646 (jiffies - tape->avg_time) / 1024;
648 tape->avg_time = jiffies;
651 tape->first_frame += blocks;
652 rq->current_nr_sectors -= blocks;
655 uptodate = pc->error;
656 } else if (pc->c[0] == READ_POSITION && uptodate) {
657 u8 *readpos = tape->pc->buf;
659 debug_log(DBG_SENSE, "BOP - %s\n",
660 (readpos[0] & 0x80) ? "Yes" : "No");
661 debug_log(DBG_SENSE, "EOP - %s\n",
662 (readpos[0] & 0x40) ? "Yes" : "No");
664 if (readpos[0] & 0x4) {
665 printk(KERN_INFO "ide-tape: Block location is unknown"
667 clear_bit(IDETAPE_FLAG_ADDRESS_VALID, &tape->flags);
670 debug_log(DBG_SENSE, "Block Location - %u\n",
671 be32_to_cpu(*(u32 *)&readpos[4]));
673 tape->partition = readpos[1];
674 tape->first_frame = be32_to_cpu(*(u32 *)&readpos[4]);
675 set_bit(IDETAPE_FLAG_ADDRESS_VALID, &tape->flags);
679 idetape_end_request(drive, uptodate, 0);
682 static void idetape_init_pc(struct ide_atapi_pc *pc)
684 memset(pc->c, 0, 12);
688 pc->buf = pc->pc_buf;
689 pc->buf_size = IDETAPE_PC_BUFFER_SIZE;
692 pc->callback = ide_tape_callback;
695 static void idetape_create_request_sense_cmd(struct ide_atapi_pc *pc)
698 pc->c[0] = REQUEST_SENSE;
703 static void idetape_init_rq(struct request *rq, u8 cmd)
705 blk_rq_init(NULL, rq);
706 rq->cmd_type = REQ_TYPE_SPECIAL;
711 * Generate a new packet command request in front of the request queue, before
712 * the current request, so that it will be processed immediately, on the next
713 * pass through the driver. The function below is called from the request
714 * handling part of the driver (the "bottom" part). Safe storage for the request
715 * should be allocated with ide_tape_next_{pc,rq}_storage() prior to that.
717 * Memory for those requests is pre-allocated at initialization time, and is
718 * limited to IDETAPE_PC_STACK requests. We assume that we have enough space for
719 * the maximum possible number of inter-dependent packet commands.
721 * The higher level of the driver - The ioctl handler and the character device
722 * handling functions should queue request to the lower level part and wait for
723 * their completion using idetape_queue_pc_tail or idetape_queue_rw_tail.
725 static void idetape_queue_pc_head(ide_drive_t *drive, struct ide_atapi_pc *pc,
728 struct ide_tape_obj *tape = drive->driver_data;
730 idetape_init_rq(rq, REQ_IDETAPE_PC1);
731 rq->cmd_flags |= REQ_PREEMPT;
732 rq->buffer = (char *) pc;
733 rq->rq_disk = tape->disk;
734 ide_do_drive_cmd(drive, rq);
738 * idetape_retry_pc is called when an error was detected during the
739 * last packet command. We queue a request sense packet command in
740 * the head of the request list.
742 static void idetape_retry_pc(ide_drive_t *drive)
744 idetape_tape_t *tape = drive->driver_data;
745 struct ide_atapi_pc *pc;
748 (void)ide_read_error(drive);
749 pc = idetape_next_pc_storage(drive);
750 rq = idetape_next_rq_storage(drive);
751 idetape_create_request_sense_cmd(pc);
752 set_bit(IDETAPE_FLAG_IGNORE_DSC, &tape->flags);
753 idetape_queue_pc_head(drive, pc, rq);
757 * Postpone the current request so that ide.c will be able to service requests
758 * from another device on the same hwgroup while we are polling for DSC.
760 static void idetape_postpone_request(ide_drive_t *drive)
762 idetape_tape_t *tape = drive->driver_data;
764 debug_log(DBG_PROCS, "Enter %s\n", __func__);
766 tape->postponed_rq = HWGROUP(drive)->rq;
767 ide_stall_queue(drive, tape->dsc_poll_freq);
770 static void ide_tape_handle_dsc(ide_drive_t *drive)
772 idetape_tape_t *tape = drive->driver_data;
774 /* Media access command */
775 tape->dsc_polling_start = jiffies;
776 tape->dsc_poll_freq = IDETAPE_DSC_MA_FAST;
777 tape->dsc_timeout = jiffies + IDETAPE_DSC_MA_TIMEOUT;
778 /* Allow ide.c to handle other requests */
779 idetape_postpone_request(drive);
782 static void ide_tape_io_buffers(ide_drive_t *drive, struct ide_atapi_pc *pc,
783 unsigned int bcount, int write)
786 idetape_output_buffers(drive, pc, bcount);
788 idetape_input_buffers(drive, pc, bcount);
792 * This is the usual interrupt handler which will be called during a packet
793 * command. We will transfer some of the data (as requested by the drive) and
794 * will re-point interrupt handler to us. When data transfer is finished, we
795 * will act according to the algorithm described before
798 static ide_startstop_t idetape_pc_intr(ide_drive_t *drive)
800 idetape_tape_t *tape = drive->driver_data;
802 return ide_pc_intr(drive, tape->pc, idetape_pc_intr, IDETAPE_WAIT_CMD,
803 NULL, idetape_update_buffers, idetape_retry_pc,
804 ide_tape_handle_dsc, ide_tape_io_buffers);
808 * Packet Command Interface
810 * The current Packet Command is available in tape->pc, and will not change
811 * until we finish handling it. Each packet command is associated with a
812 * callback function that will be called when the command is finished.
814 * The handling will be done in three stages:
816 * 1. idetape_issue_pc will send the packet command to the drive, and will set
817 * the interrupt handler to idetape_pc_intr.
819 * 2. On each interrupt, idetape_pc_intr will be called. This step will be
820 * repeated until the device signals us that no more interrupts will be issued.
822 * 3. ATAPI Tape media access commands have immediate status with a delayed
823 * process. In case of a successful initiation of a media access packet command,
824 * the DSC bit will be set when the actual execution of the command is finished.
825 * Since the tape drive will not issue an interrupt, we have to poll for this
826 * event. In this case, we define the request as "low priority request" by
827 * setting rq_status to IDETAPE_RQ_POSTPONED, set a timer to poll for DSC and
830 * ide.c will then give higher priority to requests which originate from the
831 * other device, until will change rq_status to RQ_ACTIVE.
833 * 4. When the packet command is finished, it will be checked for errors.
835 * 5. In case an error was found, we queue a request sense packet command in
836 * front of the request queue and retry the operation up to
837 * IDETAPE_MAX_PC_RETRIES times.
839 * 6. In case no error was found, or we decided to give up and not to retry
840 * again, the callback function will be called and then we will handle the next
843 static ide_startstop_t idetape_transfer_pc(ide_drive_t *drive)
845 idetape_tape_t *tape = drive->driver_data;
847 return ide_transfer_pc(drive, tape->pc, idetape_pc_intr,
848 IDETAPE_WAIT_CMD, NULL);
851 static ide_startstop_t idetape_issue_pc(ide_drive_t *drive,
852 struct ide_atapi_pc *pc)
854 idetape_tape_t *tape = drive->driver_data;
856 if (tape->pc->c[0] == REQUEST_SENSE &&
857 pc->c[0] == REQUEST_SENSE) {
858 printk(KERN_ERR "ide-tape: possible ide-tape.c bug - "
859 "Two request sense in serial were issued\n");
862 if (tape->failed_pc == NULL && pc->c[0] != REQUEST_SENSE)
863 tape->failed_pc = pc;
864 /* Set the current packet command */
867 if (pc->retries > IDETAPE_MAX_PC_RETRIES ||
868 (pc->flags & PC_FLAG_ABORT)) {
870 * We will "abort" retrying a packet command in case legitimate
871 * error code was received (crossing a filemark, or end of the
872 * media, for example).
874 if (!(pc->flags & PC_FLAG_ABORT)) {
875 if (!(pc->c[0] == TEST_UNIT_READY &&
876 tape->sense_key == 2 && tape->asc == 4 &&
877 (tape->ascq == 1 || tape->ascq == 8))) {
878 printk(KERN_ERR "ide-tape: %s: I/O error, "
879 "pc = %2x, key = %2x, "
880 "asc = %2x, ascq = %2x\n",
881 tape->name, pc->c[0],
882 tape->sense_key, tape->asc,
886 pc->error = IDETAPE_ERROR_GENERAL;
888 tape->failed_pc = NULL;
892 debug_log(DBG_SENSE, "Retry #%d, cmd = %02X\n", pc->retries, pc->c[0]);
896 return ide_issue_pc(drive, pc, idetape_transfer_pc,
897 IDETAPE_WAIT_CMD, NULL);
900 /* A mode sense command is used to "sense" tape parameters. */
901 static void idetape_create_mode_sense_cmd(struct ide_atapi_pc *pc, u8 page_code)
904 pc->c[0] = MODE_SENSE;
905 if (page_code != IDETAPE_BLOCK_DESCRIPTOR)
906 /* DBD = 1 - Don't return block descriptors */
908 pc->c[2] = page_code;
910 * Changed pc->c[3] to 0 (255 will at best return unused info).
912 * For SCSI this byte is defined as subpage instead of high byte
913 * of length and some IDE drives seem to interpret it this way
914 * and return an error when 255 is used.
917 /* We will just discard data in that case */
919 if (page_code == IDETAPE_BLOCK_DESCRIPTOR)
921 else if (page_code == IDETAPE_CAPABILITIES_PAGE)
927 static ide_startstop_t idetape_media_access_finished(ide_drive_t *drive)
929 ide_hwif_t *hwif = drive->hwif;
930 idetape_tape_t *tape = drive->driver_data;
931 struct ide_atapi_pc *pc = tape->pc;
934 stat = hwif->tp_ops->read_status(hwif);
936 if (stat & SEEK_STAT) {
937 if (stat & ERR_STAT) {
939 if (pc->c[0] != TEST_UNIT_READY)
940 printk(KERN_ERR "ide-tape: %s: I/O error, ",
942 /* Retry operation */
943 idetape_retry_pc(drive);
948 pc->error = IDETAPE_ERROR_GENERAL;
949 tape->failed_pc = NULL;
955 static void ide_tape_create_rw_cmd(idetape_tape_t *tape,
956 struct ide_atapi_pc *pc, unsigned int length,
957 struct idetape_bh *bh, u8 opcode)
960 put_unaligned(cpu_to_be32(length), (unsigned int *) &pc->c[1]);
964 pc->buf_size = length * tape->blk_size;
965 pc->req_xfer = pc->buf_size;
966 if (pc->req_xfer == tape->buffer_size)
967 pc->flags |= PC_FLAG_DMA_OK;
969 if (opcode == READ_6) {
971 atomic_set(&bh->b_count, 0);
972 } else if (opcode == WRITE_6) {
974 pc->flags |= PC_FLAG_WRITING;
975 pc->b_data = bh->b_data;
976 pc->b_count = atomic_read(&bh->b_count);
980 static ide_startstop_t idetape_do_request(ide_drive_t *drive,
981 struct request *rq, sector_t block)
983 ide_hwif_t *hwif = drive->hwif;
984 idetape_tape_t *tape = drive->driver_data;
985 struct ide_atapi_pc *pc = NULL;
986 struct request *postponed_rq = tape->postponed_rq;
989 debug_log(DBG_SENSE, "sector: %ld, nr_sectors: %ld,"
990 " current_nr_sectors: %d\n",
991 rq->sector, rq->nr_sectors, rq->current_nr_sectors);
993 if (!blk_special_request(rq)) {
994 /* We do not support buffer cache originated requests. */
995 printk(KERN_NOTICE "ide-tape: %s: Unsupported request in "
996 "request queue (%d)\n", drive->name, rq->cmd_type);
997 ide_end_request(drive, 0, 0);
1001 /* Retry a failed packet command */
1002 if (tape->failed_pc && tape->pc->c[0] == REQUEST_SENSE) {
1003 pc = tape->failed_pc;
1007 if (postponed_rq != NULL)
1008 if (rq != postponed_rq) {
1009 printk(KERN_ERR "ide-tape: ide-tape.c bug - "
1010 "Two DSC requests were queued\n");
1011 idetape_end_request(drive, 0, 0);
1015 tape->postponed_rq = NULL;
1018 * If the tape is still busy, postpone our request and service
1019 * the other device meanwhile.
1021 stat = hwif->tp_ops->read_status(hwif);
1023 if (!drive->dsc_overlap && !(rq->cmd[0] & REQ_IDETAPE_PC2))
1024 set_bit(IDETAPE_FLAG_IGNORE_DSC, &tape->flags);
1026 if (drive->post_reset == 1) {
1027 set_bit(IDETAPE_FLAG_IGNORE_DSC, &tape->flags);
1028 drive->post_reset = 0;
1031 if (!test_and_clear_bit(IDETAPE_FLAG_IGNORE_DSC, &tape->flags) &&
1032 (stat & SEEK_STAT) == 0) {
1033 if (postponed_rq == NULL) {
1034 tape->dsc_polling_start = jiffies;
1035 tape->dsc_poll_freq = tape->best_dsc_rw_freq;
1036 tape->dsc_timeout = jiffies + IDETAPE_DSC_RW_TIMEOUT;
1037 } else if (time_after(jiffies, tape->dsc_timeout)) {
1038 printk(KERN_ERR "ide-tape: %s: DSC timeout\n",
1040 if (rq->cmd[0] & REQ_IDETAPE_PC2) {
1041 idetape_media_access_finished(drive);
1044 return ide_do_reset(drive);
1046 } else if (time_after(jiffies,
1047 tape->dsc_polling_start +
1048 IDETAPE_DSC_MA_THRESHOLD))
1049 tape->dsc_poll_freq = IDETAPE_DSC_MA_SLOW;
1050 idetape_postpone_request(drive);
1053 if (rq->cmd[0] & REQ_IDETAPE_READ) {
1054 pc = idetape_next_pc_storage(drive);
1055 ide_tape_create_rw_cmd(tape, pc, rq->current_nr_sectors,
1056 (struct idetape_bh *)rq->special,
1060 if (rq->cmd[0] & REQ_IDETAPE_WRITE) {
1061 pc = idetape_next_pc_storage(drive);
1062 ide_tape_create_rw_cmd(tape, pc, rq->current_nr_sectors,
1063 (struct idetape_bh *)rq->special,
1067 if (rq->cmd[0] & REQ_IDETAPE_PC1) {
1068 pc = (struct ide_atapi_pc *) rq->buffer;
1069 rq->cmd[0] &= ~(REQ_IDETAPE_PC1);
1070 rq->cmd[0] |= REQ_IDETAPE_PC2;
1073 if (rq->cmd[0] & REQ_IDETAPE_PC2) {
1074 idetape_media_access_finished(drive);
1079 if (test_bit(IDETAPE_FLAG_DRQ_INTERRUPT, &tape->flags))
1080 pc->flags |= PC_FLAG_DRQ_INTERRUPT;
1082 return idetape_issue_pc(drive, pc);
1086 * The function below uses __get_free_pages to allocate a data buffer of size
1087 * tape->buffer_size (or a bit more). We attempt to combine sequential pages as
1090 * It returns a pointer to the newly allocated buffer, or NULL in case of
1093 static struct idetape_bh *ide_tape_kmalloc_buffer(idetape_tape_t *tape,
1094 int full, int clear)
1096 struct idetape_bh *prev_bh, *bh, *merge_bh;
1097 int pages = tape->pages_per_buffer;
1098 unsigned int order, b_allocd;
1099 char *b_data = NULL;
1101 merge_bh = kmalloc(sizeof(struct idetape_bh), GFP_KERNEL);
1106 order = fls(pages) - 1;
1107 bh->b_data = (char *) __get_free_pages(GFP_KERNEL, order);
1110 b_allocd = (1 << order) * PAGE_SIZE;
1114 memset(bh->b_data, 0, b_allocd);
1115 bh->b_reqnext = NULL;
1116 bh->b_size = b_allocd;
1117 atomic_set(&bh->b_count, full ? bh->b_size : 0);
1120 order = fls(pages) - 1;
1121 b_data = (char *) __get_free_pages(GFP_KERNEL, order);
1124 b_allocd = (1 << order) * PAGE_SIZE;
1127 memset(b_data, 0, b_allocd);
1129 /* newly allocated page frames below buffer header or ...*/
1130 if (bh->b_data == b_data + b_allocd) {
1131 bh->b_size += b_allocd;
1132 bh->b_data -= b_allocd;
1134 atomic_add(b_allocd, &bh->b_count);
1137 /* they are above the header */
1138 if (b_data == bh->b_data + bh->b_size) {
1139 bh->b_size += b_allocd;
1141 atomic_add(b_allocd, &bh->b_count);
1145 bh = kmalloc(sizeof(struct idetape_bh), GFP_KERNEL);
1147 free_pages((unsigned long) b_data, order);
1150 bh->b_reqnext = NULL;
1151 bh->b_data = b_data;
1152 bh->b_size = b_allocd;
1153 atomic_set(&bh->b_count, full ? bh->b_size : 0);
1154 prev_bh->b_reqnext = bh;
1159 bh->b_size -= tape->excess_bh_size;
1161 atomic_sub(tape->excess_bh_size, &bh->b_count);
1164 ide_tape_kfree_buffer(tape);
1168 static int idetape_copy_stage_from_user(idetape_tape_t *tape,
1169 const char __user *buf, int n)
1171 struct idetape_bh *bh = tape->bh;
1177 printk(KERN_ERR "ide-tape: bh == NULL in %s\n",
1181 count = min((unsigned int)
1182 (bh->b_size - atomic_read(&bh->b_count)),
1184 if (copy_from_user(bh->b_data + atomic_read(&bh->b_count), buf,
1188 atomic_add(count, &bh->b_count);
1190 if (atomic_read(&bh->b_count) == bh->b_size) {
1193 atomic_set(&bh->b_count, 0);
1200 static int idetape_copy_stage_to_user(idetape_tape_t *tape, char __user *buf,
1203 struct idetape_bh *bh = tape->bh;
1209 printk(KERN_ERR "ide-tape: bh == NULL in %s\n",
1213 count = min(tape->b_count, n);
1214 if (copy_to_user(buf, tape->b_data, count))
1217 tape->b_data += count;
1218 tape->b_count -= count;
1220 if (!tape->b_count) {
1224 tape->b_data = bh->b_data;
1225 tape->b_count = atomic_read(&bh->b_count);
1232 static void idetape_init_merge_buffer(idetape_tape_t *tape)
1234 struct idetape_bh *bh = tape->merge_bh;
1235 tape->bh = tape->merge_bh;
1237 if (tape->chrdev_dir == IDETAPE_DIR_WRITE)
1238 atomic_set(&bh->b_count, 0);
1240 tape->b_data = bh->b_data;
1241 tape->b_count = atomic_read(&bh->b_count);
1246 * Write a filemark if write_filemark=1. Flush the device buffers without
1247 * writing a filemark otherwise.
1249 static void idetape_create_write_filemark_cmd(ide_drive_t *drive,
1250 struct ide_atapi_pc *pc, int write_filemark)
1252 idetape_init_pc(pc);
1253 pc->c[0] = WRITE_FILEMARKS;
1254 pc->c[4] = write_filemark;
1255 pc->flags |= PC_FLAG_WAIT_FOR_DSC;
1258 static void idetape_create_test_unit_ready_cmd(struct ide_atapi_pc *pc)
1260 idetape_init_pc(pc);
1261 pc->c[0] = TEST_UNIT_READY;
1265 * We add a special packet command request to the tail of the request queue, and
1266 * wait for it to be serviced. This is not to be called from within the request
1267 * handling part of the driver! We allocate here data on the stack and it is
1268 * valid until the request is finished. This is not the case for the bottom part
1269 * of the driver, where we are always leaving the functions to wait for an
1270 * interrupt or a timer event.
1272 * From the bottom part of the driver, we should allocate safe memory using
1273 * idetape_next_pc_storage() and ide_tape_next_rq_storage(), and add the request
1274 * to the request list without waiting for it to be serviced! In that case, we
1275 * usually use idetape_queue_pc_head().
1277 static int idetape_queue_pc_tail(ide_drive_t *drive, struct ide_atapi_pc *pc)
1279 struct ide_tape_obj *tape = drive->driver_data;
1283 rq = blk_get_request(drive->queue, READ, __GFP_WAIT);
1284 rq->cmd_type = REQ_TYPE_SPECIAL;
1285 rq->cmd[0] = REQ_IDETAPE_PC1;
1286 rq->buffer = (char *)pc;
1287 error = blk_execute_rq(drive->queue, tape->disk, rq, 0);
1288 blk_put_request(rq);
1292 static void idetape_create_load_unload_cmd(ide_drive_t *drive,
1293 struct ide_atapi_pc *pc, int cmd)
1295 idetape_init_pc(pc);
1296 pc->c[0] = START_STOP;
1298 pc->flags |= PC_FLAG_WAIT_FOR_DSC;
1301 static int idetape_wait_ready(ide_drive_t *drive, unsigned long timeout)
1303 idetape_tape_t *tape = drive->driver_data;
1304 struct ide_atapi_pc pc;
1305 int load_attempted = 0;
1307 /* Wait for the tape to become ready */
1308 set_bit(IDETAPE_FLAG_MEDIUM_PRESENT, &tape->flags);
1310 while (time_before(jiffies, timeout)) {
1311 idetape_create_test_unit_ready_cmd(&pc);
1312 if (!idetape_queue_pc_tail(drive, &pc))
1314 if ((tape->sense_key == 2 && tape->asc == 4 && tape->ascq == 2)
1315 || (tape->asc == 0x3A)) {
1319 idetape_create_load_unload_cmd(drive, &pc,
1320 IDETAPE_LU_LOAD_MASK);
1321 idetape_queue_pc_tail(drive, &pc);
1323 /* not about to be ready */
1324 } else if (!(tape->sense_key == 2 && tape->asc == 4 &&
1325 (tape->ascq == 1 || tape->ascq == 8)))
1332 static int idetape_flush_tape_buffers(ide_drive_t *drive)
1334 struct ide_atapi_pc pc;
1337 idetape_create_write_filemark_cmd(drive, &pc, 0);
1338 rc = idetape_queue_pc_tail(drive, &pc);
1341 idetape_wait_ready(drive, 60 * 5 * HZ);
1345 static void idetape_create_read_position_cmd(struct ide_atapi_pc *pc)
1347 idetape_init_pc(pc);
1348 pc->c[0] = READ_POSITION;
1352 static int idetape_read_position(ide_drive_t *drive)
1354 idetape_tape_t *tape = drive->driver_data;
1355 struct ide_atapi_pc pc;
1358 debug_log(DBG_PROCS, "Enter %s\n", __func__);
1360 idetape_create_read_position_cmd(&pc);
1361 if (idetape_queue_pc_tail(drive, &pc))
1363 position = tape->first_frame;
1367 static void idetape_create_locate_cmd(ide_drive_t *drive,
1368 struct ide_atapi_pc *pc,
1369 unsigned int block, u8 partition, int skip)
1371 idetape_init_pc(pc);
1372 pc->c[0] = POSITION_TO_ELEMENT;
1374 put_unaligned(cpu_to_be32(block), (unsigned int *) &pc->c[3]);
1375 pc->c[8] = partition;
1376 pc->flags |= PC_FLAG_WAIT_FOR_DSC;
1379 static int idetape_create_prevent_cmd(ide_drive_t *drive,
1380 struct ide_atapi_pc *pc, int prevent)
1382 idetape_tape_t *tape = drive->driver_data;
1384 /* device supports locking according to capabilities page */
1385 if (!(tape->caps[6] & 0x01))
1388 idetape_init_pc(pc);
1389 pc->c[0] = ALLOW_MEDIUM_REMOVAL;
1394 static void __ide_tape_discard_merge_buffer(ide_drive_t *drive)
1396 idetape_tape_t *tape = drive->driver_data;
1398 if (tape->chrdev_dir != IDETAPE_DIR_READ)
1401 clear_bit(IDETAPE_FLAG_FILEMARK, &tape->flags);
1402 tape->merge_bh_size = 0;
1403 if (tape->merge_bh != NULL) {
1404 ide_tape_kfree_buffer(tape);
1405 tape->merge_bh = NULL;
1408 tape->chrdev_dir = IDETAPE_DIR_NONE;
1412 * Position the tape to the requested block using the LOCATE packet command.
1413 * A READ POSITION command is then issued to check where we are positioned. Like
1414 * all higher level operations, we queue the commands at the tail of the request
1415 * queue and wait for their completion.
1417 static int idetape_position_tape(ide_drive_t *drive, unsigned int block,
1418 u8 partition, int skip)
1420 idetape_tape_t *tape = drive->driver_data;
1422 struct ide_atapi_pc pc;
1424 if (tape->chrdev_dir == IDETAPE_DIR_READ)
1425 __ide_tape_discard_merge_buffer(drive);
1426 idetape_wait_ready(drive, 60 * 5 * HZ);
1427 idetape_create_locate_cmd(drive, &pc, block, partition, skip);
1428 retval = idetape_queue_pc_tail(drive, &pc);
1432 idetape_create_read_position_cmd(&pc);
1433 return (idetape_queue_pc_tail(drive, &pc));
1436 static void ide_tape_discard_merge_buffer(ide_drive_t *drive,
1437 int restore_position)
1439 idetape_tape_t *tape = drive->driver_data;
1442 __ide_tape_discard_merge_buffer(drive);
1443 if (restore_position) {
1444 position = idetape_read_position(drive);
1445 seek = position > 0 ? position : 0;
1446 if (idetape_position_tape(drive, seek, 0, 0)) {
1447 printk(KERN_INFO "ide-tape: %s: position_tape failed in"
1448 " %s\n", tape->name, __func__);
1455 * Generate a read/write request for the block device interface and wait for it
1458 static int idetape_queue_rw_tail(ide_drive_t *drive, int cmd, int blocks,
1459 struct idetape_bh *bh)
1461 idetape_tape_t *tape = drive->driver_data;
1465 debug_log(DBG_SENSE, "%s: cmd=%d\n", __func__, cmd);
1467 rq = blk_get_request(drive->queue, READ, __GFP_WAIT);
1468 rq->cmd_type = REQ_TYPE_SPECIAL;
1470 rq->rq_disk = tape->disk;
1471 rq->special = (void *)bh;
1472 rq->sector = tape->first_frame;
1473 rq->nr_sectors = blocks;
1474 rq->current_nr_sectors = blocks;
1475 blk_execute_rq(drive->queue, tape->disk, rq, 0);
1477 errors = rq->errors;
1478 ret = tape->blk_size * (blocks - rq->current_nr_sectors);
1479 blk_put_request(rq);
1481 if ((cmd & (REQ_IDETAPE_READ | REQ_IDETAPE_WRITE)) == 0)
1485 idetape_init_merge_buffer(tape);
1486 if (errors == IDETAPE_ERROR_GENERAL)
1491 static void idetape_create_inquiry_cmd(struct ide_atapi_pc *pc)
1493 idetape_init_pc(pc);
1499 static void idetape_create_rewind_cmd(ide_drive_t *drive,
1500 struct ide_atapi_pc *pc)
1502 idetape_init_pc(pc);
1503 pc->c[0] = REZERO_UNIT;
1504 pc->flags |= PC_FLAG_WAIT_FOR_DSC;
1507 static void idetape_create_erase_cmd(struct ide_atapi_pc *pc)
1509 idetape_init_pc(pc);
1512 pc->flags |= PC_FLAG_WAIT_FOR_DSC;
1515 static void idetape_create_space_cmd(struct ide_atapi_pc *pc, int count, u8 cmd)
1517 idetape_init_pc(pc);
1519 put_unaligned(cpu_to_be32(count), (unsigned int *) &pc->c[1]);
1521 pc->flags |= PC_FLAG_WAIT_FOR_DSC;
1524 /* Queue up a character device originated write request. */
1525 static int idetape_add_chrdev_write_request(ide_drive_t *drive, int blocks)
1527 idetape_tape_t *tape = drive->driver_data;
1529 debug_log(DBG_CHRDEV, "Enter %s\n", __func__);
1531 return idetape_queue_rw_tail(drive, REQ_IDETAPE_WRITE,
1532 blocks, tape->merge_bh);
1535 static void ide_tape_flush_merge_buffer(ide_drive_t *drive)
1537 idetape_tape_t *tape = drive->driver_data;
1539 struct idetape_bh *bh;
1541 if (tape->chrdev_dir != IDETAPE_DIR_WRITE) {
1542 printk(KERN_ERR "ide-tape: bug: Trying to empty merge buffer"
1543 " but we are not writing.\n");
1546 if (tape->merge_bh_size > tape->buffer_size) {
1547 printk(KERN_ERR "ide-tape: bug: merge_buffer too big\n");
1548 tape->merge_bh_size = tape->buffer_size;
1550 if (tape->merge_bh_size) {
1551 blocks = tape->merge_bh_size / tape->blk_size;
1552 if (tape->merge_bh_size % tape->blk_size) {
1556 i = tape->blk_size - tape->merge_bh_size %
1558 bh = tape->bh->b_reqnext;
1560 atomic_set(&bh->b_count, 0);
1566 printk(KERN_INFO "ide-tape: bug,"
1570 min = min(i, (unsigned int)(bh->b_size -
1571 atomic_read(&bh->b_count)));
1572 memset(bh->b_data + atomic_read(&bh->b_count),
1574 atomic_add(min, &bh->b_count);
1579 (void) idetape_add_chrdev_write_request(drive, blocks);
1580 tape->merge_bh_size = 0;
1582 if (tape->merge_bh != NULL) {
1583 ide_tape_kfree_buffer(tape);
1584 tape->merge_bh = NULL;
1586 tape->chrdev_dir = IDETAPE_DIR_NONE;
1589 static int idetape_init_read(ide_drive_t *drive)
1591 idetape_tape_t *tape = drive->driver_data;
1594 /* Initialize read operation */
1595 if (tape->chrdev_dir != IDETAPE_DIR_READ) {
1596 if (tape->chrdev_dir == IDETAPE_DIR_WRITE) {
1597 ide_tape_flush_merge_buffer(drive);
1598 idetape_flush_tape_buffers(drive);
1600 if (tape->merge_bh || tape->merge_bh_size) {
1601 printk(KERN_ERR "ide-tape: merge_bh_size should be"
1603 tape->merge_bh_size = 0;
1605 tape->merge_bh = ide_tape_kmalloc_buffer(tape, 0, 0);
1606 if (!tape->merge_bh)
1608 tape->chrdev_dir = IDETAPE_DIR_READ;
1611 * Issue a read 0 command to ensure that DSC handshake is
1612 * switched from completion mode to buffer available mode.
1613 * No point in issuing this if DSC overlap isn't supported, some
1614 * drives (Seagate STT3401A) will return an error.
1616 if (drive->dsc_overlap) {
1617 bytes_read = idetape_queue_rw_tail(drive,
1618 REQ_IDETAPE_READ, 0,
1620 if (bytes_read < 0) {
1621 ide_tape_kfree_buffer(tape);
1622 tape->merge_bh = NULL;
1623 tape->chrdev_dir = IDETAPE_DIR_NONE;
1632 /* called from idetape_chrdev_read() to service a chrdev read request. */
1633 static int idetape_add_chrdev_read_request(ide_drive_t *drive, int blocks)
1635 idetape_tape_t *tape = drive->driver_data;
1637 debug_log(DBG_PROCS, "Enter %s, %d blocks\n", __func__, blocks);
1639 /* If we are at a filemark, return a read length of 0 */
1640 if (test_bit(IDETAPE_FLAG_FILEMARK, &tape->flags))
1643 idetape_init_read(drive);
1645 return idetape_queue_rw_tail(drive, REQ_IDETAPE_READ, blocks,
1649 static void idetape_pad_zeros(ide_drive_t *drive, int bcount)
1651 idetape_tape_t *tape = drive->driver_data;
1652 struct idetape_bh *bh;
1658 bh = tape->merge_bh;
1659 count = min(tape->buffer_size, bcount);
1661 blocks = count / tape->blk_size;
1663 atomic_set(&bh->b_count,
1664 min(count, (unsigned int)bh->b_size));
1665 memset(bh->b_data, 0, atomic_read(&bh->b_count));
1666 count -= atomic_read(&bh->b_count);
1669 idetape_queue_rw_tail(drive, REQ_IDETAPE_WRITE, blocks,
1675 * Rewinds the tape to the Beginning Of the current Partition (BOP). We
1676 * currently support only one partition.
1678 static int idetape_rewind_tape(ide_drive_t *drive)
1681 struct ide_atapi_pc pc;
1682 idetape_tape_t *tape;
1683 tape = drive->driver_data;
1685 debug_log(DBG_SENSE, "Enter %s\n", __func__);
1687 idetape_create_rewind_cmd(drive, &pc);
1688 retval = idetape_queue_pc_tail(drive, &pc);
1692 idetape_create_read_position_cmd(&pc);
1693 retval = idetape_queue_pc_tail(drive, &pc);
1699 /* mtio.h compatible commands should be issued to the chrdev interface. */
1700 static int idetape_blkdev_ioctl(ide_drive_t *drive, unsigned int cmd,
1703 idetape_tape_t *tape = drive->driver_data;
1704 void __user *argp = (void __user *)arg;
1706 struct idetape_config {
1707 int dsc_rw_frequency;
1708 int dsc_media_access_frequency;
1712 debug_log(DBG_PROCS, "Enter %s\n", __func__);
1716 if (copy_from_user(&config, argp, sizeof(config)))
1718 tape->best_dsc_rw_freq = config.dsc_rw_frequency;
1721 config.dsc_rw_frequency = (int) tape->best_dsc_rw_freq;
1722 config.nr_stages = 1;
1723 if (copy_to_user(argp, &config, sizeof(config)))
1732 static int idetape_space_over_filemarks(ide_drive_t *drive, short mt_op,
1735 idetape_tape_t *tape = drive->driver_data;
1736 struct ide_atapi_pc pc;
1737 int retval, count = 0;
1738 int sprev = !!(tape->caps[4] & 0x20);
1742 if (MTBSF == mt_op || MTBSFM == mt_op) {
1745 mt_count = -mt_count;
1748 if (tape->chrdev_dir == IDETAPE_DIR_READ) {
1749 tape->merge_bh_size = 0;
1750 if (test_and_clear_bit(IDETAPE_FLAG_FILEMARK, &tape->flags))
1752 ide_tape_discard_merge_buffer(drive, 0);
1758 idetape_create_space_cmd(&pc, mt_count - count,
1759 IDETAPE_SPACE_OVER_FILEMARK);
1760 return idetape_queue_pc_tail(drive, &pc);
1765 retval = idetape_space_over_filemarks(drive, MTFSF,
1769 count = (MTBSFM == mt_op ? 1 : -1);
1770 return idetape_space_over_filemarks(drive, MTFSF, count);
1772 printk(KERN_ERR "ide-tape: MTIO operation %d not supported\n",
1779 * Our character device read / write functions.
1781 * The tape is optimized to maximize throughput when it is transferring an
1782 * integral number of the "continuous transfer limit", which is a parameter of
1783 * the specific tape (26kB on my particular tape, 32kB for Onstream).
1785 * As of version 1.3 of the driver, the character device provides an abstract
1786 * continuous view of the media - any mix of block sizes (even 1 byte) on the
1787 * same backup/restore procedure is supported. The driver will internally
1788 * convert the requests to the recommended transfer unit, so that an unmatch
1789 * between the user's block size to the recommended size will only result in a
1790 * (slightly) increased driver overhead, but will no longer hit performance.
1791 * This is not applicable to Onstream.
1793 static ssize_t idetape_chrdev_read(struct file *file, char __user *buf,
1794 size_t count, loff_t *ppos)
1796 struct ide_tape_obj *tape = ide_tape_f(file);
1797 ide_drive_t *drive = tape->drive;
1798 ssize_t bytes_read, temp, actually_read = 0, rc;
1800 u16 ctl = *(u16 *)&tape->caps[12];
1802 debug_log(DBG_CHRDEV, "Enter %s, count %Zd\n", __func__, count);
1804 if (tape->chrdev_dir != IDETAPE_DIR_READ) {
1805 if (test_bit(IDETAPE_FLAG_DETECT_BS, &tape->flags))
1806 if (count > tape->blk_size &&
1807 (count % tape->blk_size) == 0)
1808 tape->user_bs_factor = count / tape->blk_size;
1810 rc = idetape_init_read(drive);
1815 if (tape->merge_bh_size) {
1816 actually_read = min((unsigned int)(tape->merge_bh_size),
1817 (unsigned int)count);
1818 if (idetape_copy_stage_to_user(tape, buf, actually_read))
1820 buf += actually_read;
1821 tape->merge_bh_size -= actually_read;
1822 count -= actually_read;
1824 while (count >= tape->buffer_size) {
1825 bytes_read = idetape_add_chrdev_read_request(drive, ctl);
1826 if (bytes_read <= 0)
1828 if (idetape_copy_stage_to_user(tape, buf, bytes_read))
1831 count -= bytes_read;
1832 actually_read += bytes_read;
1835 bytes_read = idetape_add_chrdev_read_request(drive, ctl);
1836 if (bytes_read <= 0)
1838 temp = min((unsigned long)count, (unsigned long)bytes_read);
1839 if (idetape_copy_stage_to_user(tape, buf, temp))
1841 actually_read += temp;
1842 tape->merge_bh_size = bytes_read-temp;
1845 if (!actually_read && test_bit(IDETAPE_FLAG_FILEMARK, &tape->flags)) {
1846 debug_log(DBG_SENSE, "%s: spacing over filemark\n", tape->name);
1848 idetape_space_over_filemarks(drive, MTFSF, 1);
1852 return ret ? ret : actually_read;
1855 static ssize_t idetape_chrdev_write(struct file *file, const char __user *buf,
1856 size_t count, loff_t *ppos)
1858 struct ide_tape_obj *tape = ide_tape_f(file);
1859 ide_drive_t *drive = tape->drive;
1860 ssize_t actually_written = 0;
1862 u16 ctl = *(u16 *)&tape->caps[12];
1864 /* The drive is write protected. */
1865 if (tape->write_prot)
1868 debug_log(DBG_CHRDEV, "Enter %s, count %Zd\n", __func__, count);
1870 /* Initialize write operation */
1871 if (tape->chrdev_dir != IDETAPE_DIR_WRITE) {
1872 if (tape->chrdev_dir == IDETAPE_DIR_READ)
1873 ide_tape_discard_merge_buffer(drive, 1);
1874 if (tape->merge_bh || tape->merge_bh_size) {
1875 printk(KERN_ERR "ide-tape: merge_bh_size "
1876 "should be 0 now\n");
1877 tape->merge_bh_size = 0;
1879 tape->merge_bh = ide_tape_kmalloc_buffer(tape, 0, 0);
1880 if (!tape->merge_bh)
1882 tape->chrdev_dir = IDETAPE_DIR_WRITE;
1883 idetape_init_merge_buffer(tape);
1886 * Issue a write 0 command to ensure that DSC handshake is
1887 * switched from completion mode to buffer available mode. No
1888 * point in issuing this if DSC overlap isn't supported, some
1889 * drives (Seagate STT3401A) will return an error.
1891 if (drive->dsc_overlap) {
1892 ssize_t retval = idetape_queue_rw_tail(drive,
1893 REQ_IDETAPE_WRITE, 0,
1896 ide_tape_kfree_buffer(tape);
1897 tape->merge_bh = NULL;
1898 tape->chrdev_dir = IDETAPE_DIR_NONE;
1905 if (tape->merge_bh_size) {
1906 if (tape->merge_bh_size >= tape->buffer_size) {
1907 printk(KERN_ERR "ide-tape: bug: merge buf too big\n");
1908 tape->merge_bh_size = 0;
1910 actually_written = min((unsigned int)
1911 (tape->buffer_size - tape->merge_bh_size),
1912 (unsigned int)count);
1913 if (idetape_copy_stage_from_user(tape, buf, actually_written))
1915 buf += actually_written;
1916 tape->merge_bh_size += actually_written;
1917 count -= actually_written;
1919 if (tape->merge_bh_size == tape->buffer_size) {
1921 tape->merge_bh_size = 0;
1922 retval = idetape_add_chrdev_write_request(drive, ctl);
1927 while (count >= tape->buffer_size) {
1929 if (idetape_copy_stage_from_user(tape, buf, tape->buffer_size))
1931 buf += tape->buffer_size;
1932 count -= tape->buffer_size;
1933 retval = idetape_add_chrdev_write_request(drive, ctl);
1934 actually_written += tape->buffer_size;
1939 actually_written += count;
1940 if (idetape_copy_stage_from_user(tape, buf, count))
1942 tape->merge_bh_size += count;
1944 return ret ? ret : actually_written;
1947 static int idetape_write_filemark(ide_drive_t *drive)
1949 struct ide_atapi_pc pc;
1951 /* Write a filemark */
1952 idetape_create_write_filemark_cmd(drive, &pc, 1);
1953 if (idetape_queue_pc_tail(drive, &pc)) {
1954 printk(KERN_ERR "ide-tape: Couldn't write a filemark\n");
1961 * Called from idetape_chrdev_ioctl when the general mtio MTIOCTOP ioctl is
1964 * Note: MTBSF and MTBSFM are not supported when the tape doesn't support
1965 * spacing over filemarks in the reverse direction. In this case, MTFSFM is also
1966 * usually not supported.
1968 * The following commands are currently not supported:
1970 * MTFSS, MTBSS, MTWSM, MTSETDENSITY, MTSETDRVBUFFER, MT_ST_BOOLEANS,
1971 * MT_ST_WRITE_THRESHOLD.
1973 static int idetape_mtioctop(ide_drive_t *drive, short mt_op, int mt_count)
1975 idetape_tape_t *tape = drive->driver_data;
1976 struct ide_atapi_pc pc;
1979 debug_log(DBG_ERR, "Handling MTIOCTOP ioctl: mt_op=%d, mt_count=%d\n",
1989 return idetape_space_over_filemarks(drive, mt_op, mt_count);
1996 if (tape->write_prot)
1998 ide_tape_discard_merge_buffer(drive, 1);
1999 for (i = 0; i < mt_count; i++) {
2000 retval = idetape_write_filemark(drive);
2006 ide_tape_discard_merge_buffer(drive, 0);
2007 if (idetape_rewind_tape(drive))
2011 ide_tape_discard_merge_buffer(drive, 0);
2012 idetape_create_load_unload_cmd(drive, &pc,
2013 IDETAPE_LU_LOAD_MASK);
2014 return idetape_queue_pc_tail(drive, &pc);
2018 * If door is locked, attempt to unlock before
2019 * attempting to eject.
2021 if (tape->door_locked) {
2022 if (idetape_create_prevent_cmd(drive, &pc, 0))
2023 if (!idetape_queue_pc_tail(drive, &pc))
2024 tape->door_locked = DOOR_UNLOCKED;
2026 ide_tape_discard_merge_buffer(drive, 0);
2027 idetape_create_load_unload_cmd(drive, &pc,
2028 !IDETAPE_LU_LOAD_MASK);
2029 retval = idetape_queue_pc_tail(drive, &pc);
2031 clear_bit(IDETAPE_FLAG_MEDIUM_PRESENT, &tape->flags);
2034 ide_tape_discard_merge_buffer(drive, 0);
2035 return idetape_flush_tape_buffers(drive);
2037 ide_tape_discard_merge_buffer(drive, 0);
2038 idetape_create_load_unload_cmd(drive, &pc,
2039 IDETAPE_LU_RETENSION_MASK | IDETAPE_LU_LOAD_MASK);
2040 return idetape_queue_pc_tail(drive, &pc);
2042 idetape_create_space_cmd(&pc, 0, IDETAPE_SPACE_TO_EOD);
2043 return idetape_queue_pc_tail(drive, &pc);
2045 (void)idetape_rewind_tape(drive);
2046 idetape_create_erase_cmd(&pc);
2047 return idetape_queue_pc_tail(drive, &pc);
2050 if (mt_count < tape->blk_size ||
2051 mt_count % tape->blk_size)
2053 tape->user_bs_factor = mt_count / tape->blk_size;
2054 clear_bit(IDETAPE_FLAG_DETECT_BS, &tape->flags);
2056 set_bit(IDETAPE_FLAG_DETECT_BS, &tape->flags);
2059 ide_tape_discard_merge_buffer(drive, 0);
2060 return idetape_position_tape(drive,
2061 mt_count * tape->user_bs_factor, tape->partition, 0);
2063 ide_tape_discard_merge_buffer(drive, 0);
2064 return idetape_position_tape(drive, 0, mt_count, 0);
2068 if (!idetape_create_prevent_cmd(drive, &pc, 1))
2070 retval = idetape_queue_pc_tail(drive, &pc);
2073 tape->door_locked = DOOR_EXPLICITLY_LOCKED;
2076 if (!idetape_create_prevent_cmd(drive, &pc, 0))
2078 retval = idetape_queue_pc_tail(drive, &pc);
2081 tape->door_locked = DOOR_UNLOCKED;
2084 printk(KERN_ERR "ide-tape: MTIO operation %d not supported\n",
2091 * Our character device ioctls. General mtio.h magnetic io commands are
2092 * supported here, and not in the corresponding block interface. Our own
2093 * ide-tape ioctls are supported on both interfaces.
2095 static int idetape_chrdev_ioctl(struct inode *inode, struct file *file,
2096 unsigned int cmd, unsigned long arg)
2098 struct ide_tape_obj *tape = ide_tape_f(file);
2099 ide_drive_t *drive = tape->drive;
2103 int block_offset = 0, position = tape->first_frame;
2104 void __user *argp = (void __user *)arg;
2106 debug_log(DBG_CHRDEV, "Enter %s, cmd=%u\n", __func__, cmd);
2108 if (tape->chrdev_dir == IDETAPE_DIR_WRITE) {
2109 ide_tape_flush_merge_buffer(drive);
2110 idetape_flush_tape_buffers(drive);
2112 if (cmd == MTIOCGET || cmd == MTIOCPOS) {
2113 block_offset = tape->merge_bh_size /
2114 (tape->blk_size * tape->user_bs_factor);
2115 position = idetape_read_position(drive);
2121 if (copy_from_user(&mtop, argp, sizeof(struct mtop)))
2123 return idetape_mtioctop(drive, mtop.mt_op, mtop.mt_count);
2125 memset(&mtget, 0, sizeof(struct mtget));
2126 mtget.mt_type = MT_ISSCSI2;
2127 mtget.mt_blkno = position / tape->user_bs_factor - block_offset;
2129 ((tape->blk_size * tape->user_bs_factor)
2130 << MT_ST_BLKSIZE_SHIFT) & MT_ST_BLKSIZE_MASK;
2132 if (tape->drv_write_prot)
2133 mtget.mt_gstat |= GMT_WR_PROT(0xffffffff);
2135 if (copy_to_user(argp, &mtget, sizeof(struct mtget)))
2139 mtpos.mt_blkno = position / tape->user_bs_factor - block_offset;
2140 if (copy_to_user(argp, &mtpos, sizeof(struct mtpos)))
2144 if (tape->chrdev_dir == IDETAPE_DIR_READ)
2145 ide_tape_discard_merge_buffer(drive, 1);
2146 return idetape_blkdev_ioctl(drive, cmd, arg);
2151 * Do a mode sense page 0 with block descriptor and if it succeeds set the tape
2152 * block size with the reported value.
2154 static void ide_tape_get_bsize_from_bdesc(ide_drive_t *drive)
2156 idetape_tape_t *tape = drive->driver_data;
2157 struct ide_atapi_pc pc;
2159 idetape_create_mode_sense_cmd(&pc, IDETAPE_BLOCK_DESCRIPTOR);
2160 if (idetape_queue_pc_tail(drive, &pc)) {
2161 printk(KERN_ERR "ide-tape: Can't get block descriptor\n");
2162 if (tape->blk_size == 0) {
2163 printk(KERN_WARNING "ide-tape: Cannot deal with zero "
2164 "block size, assuming 32k\n");
2165 tape->blk_size = 32768;
2169 tape->blk_size = (pc.buf[4 + 5] << 16) +
2170 (pc.buf[4 + 6] << 8) +
2172 tape->drv_write_prot = (pc.buf[2] & 0x80) >> 7;
2175 static int idetape_chrdev_open(struct inode *inode, struct file *filp)
2177 unsigned int minor = iminor(inode), i = minor & ~0xc0;
2179 idetape_tape_t *tape;
2180 struct ide_atapi_pc pc;
2183 if (i >= MAX_HWIFS * MAX_DRIVES)
2187 tape = ide_tape_chrdev_get(i);
2193 debug_log(DBG_CHRDEV, "Enter %s\n", __func__);
2196 * We really want to do nonseekable_open(inode, filp); here, but some
2197 * versions of tar incorrectly call lseek on tapes and bail out if that
2198 * fails. So we disallow pread() and pwrite(), but permit lseeks.
2200 filp->f_mode &= ~(FMODE_PREAD | FMODE_PWRITE);
2202 drive = tape->drive;
2204 filp->private_data = tape;
2206 if (test_and_set_bit(IDETAPE_FLAG_BUSY, &tape->flags)) {
2211 retval = idetape_wait_ready(drive, 60 * HZ);
2213 clear_bit(IDETAPE_FLAG_BUSY, &tape->flags);
2214 printk(KERN_ERR "ide-tape: %s: drive not ready\n", tape->name);
2218 idetape_read_position(drive);
2219 if (!test_bit(IDETAPE_FLAG_ADDRESS_VALID, &tape->flags))
2220 (void)idetape_rewind_tape(drive);
2222 /* Read block size and write protect status from drive. */
2223 ide_tape_get_bsize_from_bdesc(drive);
2225 /* Set write protect flag if device is opened as read-only. */
2226 if ((filp->f_flags & O_ACCMODE) == O_RDONLY)
2227 tape->write_prot = 1;
2229 tape->write_prot = tape->drv_write_prot;
2231 /* Make sure drive isn't write protected if user wants to write. */
2232 if (tape->write_prot) {
2233 if ((filp->f_flags & O_ACCMODE) == O_WRONLY ||
2234 (filp->f_flags & O_ACCMODE) == O_RDWR) {
2235 clear_bit(IDETAPE_FLAG_BUSY, &tape->flags);
2241 /* Lock the tape drive door so user can't eject. */
2242 if (tape->chrdev_dir == IDETAPE_DIR_NONE) {
2243 if (idetape_create_prevent_cmd(drive, &pc, 1)) {
2244 if (!idetape_queue_pc_tail(drive, &pc)) {
2245 if (tape->door_locked != DOOR_EXPLICITLY_LOCKED)
2246 tape->door_locked = DOOR_LOCKED;
2259 static void idetape_write_release(ide_drive_t *drive, unsigned int minor)
2261 idetape_tape_t *tape = drive->driver_data;
2263 ide_tape_flush_merge_buffer(drive);
2264 tape->merge_bh = ide_tape_kmalloc_buffer(tape, 1, 0);
2265 if (tape->merge_bh != NULL) {
2266 idetape_pad_zeros(drive, tape->blk_size *
2267 (tape->user_bs_factor - 1));
2268 ide_tape_kfree_buffer(tape);
2269 tape->merge_bh = NULL;
2271 idetape_write_filemark(drive);
2272 idetape_flush_tape_buffers(drive);
2273 idetape_flush_tape_buffers(drive);
2276 static int idetape_chrdev_release(struct inode *inode, struct file *filp)
2278 struct ide_tape_obj *tape = ide_tape_f(filp);
2279 ide_drive_t *drive = tape->drive;
2280 struct ide_atapi_pc pc;
2281 unsigned int minor = iminor(inode);
2284 tape = drive->driver_data;
2286 debug_log(DBG_CHRDEV, "Enter %s\n", __func__);
2288 if (tape->chrdev_dir == IDETAPE_DIR_WRITE)
2289 idetape_write_release(drive, minor);
2290 if (tape->chrdev_dir == IDETAPE_DIR_READ) {
2292 ide_tape_discard_merge_buffer(drive, 1);
2295 if (minor < 128 && test_bit(IDETAPE_FLAG_MEDIUM_PRESENT, &tape->flags))
2296 (void) idetape_rewind_tape(drive);
2297 if (tape->chrdev_dir == IDETAPE_DIR_NONE) {
2298 if (tape->door_locked == DOOR_LOCKED) {
2299 if (idetape_create_prevent_cmd(drive, &pc, 0)) {
2300 if (!idetape_queue_pc_tail(drive, &pc))
2301 tape->door_locked = DOOR_UNLOCKED;
2305 clear_bit(IDETAPE_FLAG_BUSY, &tape->flags);
2312 * check the contents of the ATAPI IDENTIFY command results. We return:
2314 * 1 - If the tape can be supported by us, based on the information we have so
2317 * 0 - If this tape driver is not currently supported by us.
2319 static int idetape_identify_device(ide_drive_t *drive)
2321 u8 gcw[2], protocol, device_type, removable, packet_size;
2323 if (drive->id_read == 0)
2326 *((unsigned short *) &gcw) = drive->id->config;
2328 protocol = (gcw[1] & 0xC0) >> 6;
2329 device_type = gcw[1] & 0x1F;
2330 removable = !!(gcw[0] & 0x80);
2331 packet_size = gcw[0] & 0x3;
2333 /* Check that we can support this device */
2335 printk(KERN_ERR "ide-tape: Protocol (0x%02x) is not ATAPI\n",
2337 else if (device_type != 1)
2338 printk(KERN_ERR "ide-tape: Device type (0x%02x) is not set "
2339 "to tape\n", device_type);
2340 else if (!removable)
2341 printk(KERN_ERR "ide-tape: The removable flag is not set\n");
2342 else if (packet_size != 0) {
2343 printk(KERN_ERR "ide-tape: Packet size (0x%02x) is not 12"
2344 " bytes\n", packet_size);
2350 static void idetape_get_inquiry_results(ide_drive_t *drive)
2352 idetape_tape_t *tape = drive->driver_data;
2353 struct ide_atapi_pc pc;
2354 char fw_rev[6], vendor_id[10], product_id[18];
2356 idetape_create_inquiry_cmd(&pc);
2357 if (idetape_queue_pc_tail(drive, &pc)) {
2358 printk(KERN_ERR "ide-tape: %s: can't get INQUIRY results\n",
2362 memcpy(vendor_id, &pc.buf[8], 8);
2363 memcpy(product_id, &pc.buf[16], 16);
2364 memcpy(fw_rev, &pc.buf[32], 4);
2366 ide_fixstring(vendor_id, 10, 0);
2367 ide_fixstring(product_id, 18, 0);
2368 ide_fixstring(fw_rev, 6, 0);
2370 printk(KERN_INFO "ide-tape: %s <-> %s: %s %s rev %s\n",
2371 drive->name, tape->name, vendor_id, product_id, fw_rev);
2375 * Ask the tape about its various parameters. In particular, we will adjust our
2376 * data transfer buffer size to the recommended value as returned by the tape.
2378 static void idetape_get_mode_sense_results(ide_drive_t *drive)
2380 idetape_tape_t *tape = drive->driver_data;
2381 struct ide_atapi_pc pc;
2383 u8 speed, max_speed;
2385 idetape_create_mode_sense_cmd(&pc, IDETAPE_CAPABILITIES_PAGE);
2386 if (idetape_queue_pc_tail(drive, &pc)) {
2387 printk(KERN_ERR "ide-tape: Can't get tape parameters - assuming"
2388 " some default values\n");
2389 tape->blk_size = 512;
2390 put_unaligned(52, (u16 *)&tape->caps[12]);
2391 put_unaligned(540, (u16 *)&tape->caps[14]);
2392 put_unaligned(6*52, (u16 *)&tape->caps[16]);
2395 caps = pc.buf + 4 + pc.buf[3];
2397 /* convert to host order and save for later use */
2398 speed = be16_to_cpu(*(u16 *)&caps[14]);
2399 max_speed = be16_to_cpu(*(u16 *)&caps[8]);
2401 put_unaligned(max_speed, (u16 *)&caps[8]);
2402 put_unaligned(be16_to_cpu(*(u16 *)&caps[12]), (u16 *)&caps[12]);
2403 put_unaligned(speed, (u16 *)&caps[14]);
2404 put_unaligned(be16_to_cpu(*(u16 *)&caps[16]), (u16 *)&caps[16]);
2407 printk(KERN_INFO "ide-tape: %s: invalid tape speed "
2408 "(assuming 650KB/sec)\n", drive->name);
2409 put_unaligned(650, (u16 *)&caps[14]);
2412 printk(KERN_INFO "ide-tape: %s: invalid max_speed "
2413 "(assuming 650KB/sec)\n", drive->name);
2414 put_unaligned(650, (u16 *)&caps[8]);
2417 memcpy(&tape->caps, caps, 20);
2419 tape->blk_size = 512;
2420 else if (caps[7] & 0x04)
2421 tape->blk_size = 1024;
2424 #ifdef CONFIG_IDE_PROC_FS
2425 static void idetape_add_settings(ide_drive_t *drive)
2427 idetape_tape_t *tape = drive->driver_data;
2429 ide_add_setting(drive, "buffer", SETTING_READ, TYPE_SHORT, 0, 0xffff,
2430 1, 2, (u16 *)&tape->caps[16], NULL);
2431 ide_add_setting(drive, "speed", SETTING_READ, TYPE_SHORT, 0, 0xffff,
2432 1, 1, (u16 *)&tape->caps[14], NULL);
2433 ide_add_setting(drive, "buffer_size", SETTING_READ, TYPE_INT, 0, 0xffff,
2434 1, 1024, &tape->buffer_size, NULL);
2435 ide_add_setting(drive, "tdsc", SETTING_RW, TYPE_INT, IDETAPE_DSC_RW_MIN,
2436 IDETAPE_DSC_RW_MAX, 1000, HZ, &tape->best_dsc_rw_freq,
2438 ide_add_setting(drive, "dsc_overlap", SETTING_RW, TYPE_BYTE, 0, 1, 1,
2439 1, &drive->dsc_overlap, NULL);
2440 ide_add_setting(drive, "avg_speed", SETTING_READ, TYPE_INT, 0, 0xffff,
2441 1, 1, &tape->avg_speed, NULL);
2442 ide_add_setting(drive, "debug_mask", SETTING_RW, TYPE_INT, 0, 0xffff, 1,
2443 1, &tape->debug_mask, NULL);
2446 static inline void idetape_add_settings(ide_drive_t *drive) { ; }
2450 * The function below is called to:
2452 * 1. Initialize our various state variables.
2453 * 2. Ask the tape for its capabilities.
2454 * 3. Allocate a buffer which will be used for data transfer. The buffer size
2455 * is chosen based on the recommendation which we received in step 2.
2457 * Note that at this point ide.c already assigned us an irq, so that we can
2458 * queue requests here and wait for their completion.
2460 static void idetape_setup(ide_drive_t *drive, idetape_tape_t *tape, int minor)
2466 u16 *ctl = (u16 *)&tape->caps[12];
2468 spin_lock_init(&tape->lock);
2469 drive->dsc_overlap = 1;
2470 if (drive->hwif->host_flags & IDE_HFLAG_NO_DSC) {
2471 printk(KERN_INFO "ide-tape: %s: disabling DSC overlap\n",
2473 drive->dsc_overlap = 0;
2475 /* Seagate Travan drives do not support DSC overlap. */
2476 if (strstr(drive->id->model, "Seagate STT3401"))
2477 drive->dsc_overlap = 0;
2478 tape->minor = minor;
2479 tape->name[0] = 'h';
2480 tape->name[1] = 't';
2481 tape->name[2] = '0' + minor;
2482 tape->chrdev_dir = IDETAPE_DIR_NONE;
2483 tape->pc = tape->pc_stack;
2484 *((unsigned short *) &gcw) = drive->id->config;
2486 /* Command packet DRQ type */
2487 if (((gcw[0] & 0x60) >> 5) == 1)
2488 set_bit(IDETAPE_FLAG_DRQ_INTERRUPT, &tape->flags);
2490 idetape_get_inquiry_results(drive);
2491 idetape_get_mode_sense_results(drive);
2492 ide_tape_get_bsize_from_bdesc(drive);
2493 tape->user_bs_factor = 1;
2494 tape->buffer_size = *ctl * tape->blk_size;
2495 while (tape->buffer_size > 0xffff) {
2496 printk(KERN_NOTICE "ide-tape: decreasing stage size\n");
2498 tape->buffer_size = *ctl * tape->blk_size;
2500 buffer_size = tape->buffer_size;
2501 tape->pages_per_buffer = buffer_size / PAGE_SIZE;
2502 if (buffer_size % PAGE_SIZE) {
2503 tape->pages_per_buffer++;
2504 tape->excess_bh_size = PAGE_SIZE - buffer_size % PAGE_SIZE;
2507 /* select the "best" DSC read/write polling freq */
2508 speed = max(*(u16 *)&tape->caps[14], *(u16 *)&tape->caps[8]);
2510 t = (IDETAPE_FIFO_THRESHOLD * tape->buffer_size * HZ) / (speed * 1000);
2513 * Ensure that the number we got makes sense; limit it within
2514 * IDETAPE_DSC_RW_MIN and IDETAPE_DSC_RW_MAX.
2516 tape->best_dsc_rw_freq = clamp_t(unsigned long, t, IDETAPE_DSC_RW_MIN,
2517 IDETAPE_DSC_RW_MAX);
2518 printk(KERN_INFO "ide-tape: %s <-> %s: %dKBps, %d*%dkB buffer, "
2520 drive->name, tape->name, *(u16 *)&tape->caps[14],
2521 (*(u16 *)&tape->caps[16] * 512) / tape->buffer_size,
2522 tape->buffer_size / 1024,
2523 tape->best_dsc_rw_freq * 1000 / HZ,
2524 drive->using_dma ? ", DMA":"");
2526 idetape_add_settings(drive);
2529 static void ide_tape_remove(ide_drive_t *drive)
2531 idetape_tape_t *tape = drive->driver_data;
2533 ide_proc_unregister_driver(drive, tape->driver);
2535 ide_unregister_region(tape->disk);
2540 static void ide_tape_release(struct kref *kref)
2542 struct ide_tape_obj *tape = to_ide_tape(kref);
2543 ide_drive_t *drive = tape->drive;
2544 struct gendisk *g = tape->disk;
2546 BUG_ON(tape->merge_bh_size);
2548 drive->dsc_overlap = 0;
2549 drive->driver_data = NULL;
2550 device_destroy(idetape_sysfs_class, MKDEV(IDETAPE_MAJOR, tape->minor));
2551 device_destroy(idetape_sysfs_class,
2552 MKDEV(IDETAPE_MAJOR, tape->minor + 128));
2553 idetape_devs[tape->minor] = NULL;
2554 g->private_data = NULL;
2559 #ifdef CONFIG_IDE_PROC_FS
2560 static int proc_idetape_read_name
2561 (char *page, char **start, off_t off, int count, int *eof, void *data)
2563 ide_drive_t *drive = (ide_drive_t *) data;
2564 idetape_tape_t *tape = drive->driver_data;
2568 len = sprintf(out, "%s\n", tape->name);
2569 PROC_IDE_READ_RETURN(page, start, off, count, eof, len);
2572 static ide_proc_entry_t idetape_proc[] = {
2573 { "capacity", S_IFREG|S_IRUGO, proc_ide_read_capacity, NULL },
2574 { "name", S_IFREG|S_IRUGO, proc_idetape_read_name, NULL },
2575 { NULL, 0, NULL, NULL }
2579 static int ide_tape_probe(ide_drive_t *);
2581 static ide_driver_t idetape_driver = {
2583 .owner = THIS_MODULE,
2585 .bus = &ide_bus_type,
2587 .probe = ide_tape_probe,
2588 .remove = ide_tape_remove,
2589 .version = IDETAPE_VERSION,
2591 .supports_dsc_overlap = 1,
2592 .do_request = idetape_do_request,
2593 .end_request = idetape_end_request,
2594 .error = __ide_error,
2595 #ifdef CONFIG_IDE_PROC_FS
2596 .proc = idetape_proc,
2600 /* Our character device supporting functions, passed to register_chrdev. */
2601 static const struct file_operations idetape_fops = {
2602 .owner = THIS_MODULE,
2603 .read = idetape_chrdev_read,
2604 .write = idetape_chrdev_write,
2605 .ioctl = idetape_chrdev_ioctl,
2606 .open = idetape_chrdev_open,
2607 .release = idetape_chrdev_release,
2610 static int idetape_open(struct inode *inode, struct file *filp)
2612 struct gendisk *disk = inode->i_bdev->bd_disk;
2613 struct ide_tape_obj *tape;
2615 tape = ide_tape_get(disk);
2622 static int idetape_release(struct inode *inode, struct file *filp)
2624 struct gendisk *disk = inode->i_bdev->bd_disk;
2625 struct ide_tape_obj *tape = ide_tape_g(disk);
2632 static int idetape_ioctl(struct inode *inode, struct file *file,
2633 unsigned int cmd, unsigned long arg)
2635 struct block_device *bdev = inode->i_bdev;
2636 struct ide_tape_obj *tape = ide_tape_g(bdev->bd_disk);
2637 ide_drive_t *drive = tape->drive;
2638 int err = generic_ide_ioctl(drive, file, bdev, cmd, arg);
2640 err = idetape_blkdev_ioctl(drive, cmd, arg);
2644 static struct block_device_operations idetape_block_ops = {
2645 .owner = THIS_MODULE,
2646 .open = idetape_open,
2647 .release = idetape_release,
2648 .ioctl = idetape_ioctl,
2651 static int ide_tape_probe(ide_drive_t *drive)
2653 idetape_tape_t *tape;
2657 if (!strstr("ide-tape", drive->driver_req))
2659 if (!drive->present)
2661 if (drive->media != ide_tape)
2663 if (!idetape_identify_device(drive)) {
2664 printk(KERN_ERR "ide-tape: %s: not supported by this version of"
2665 " the driver\n", drive->name);
2668 tape = kzalloc(sizeof(idetape_tape_t), GFP_KERNEL);
2670 printk(KERN_ERR "ide-tape: %s: Can't allocate a tape struct\n",
2675 g = alloc_disk(1 << PARTN_BITS);
2679 ide_init_disk(g, drive);
2681 ide_proc_register_driver(drive, &idetape_driver);
2683 kref_init(&tape->kref);
2685 tape->drive = drive;
2686 tape->driver = &idetape_driver;
2689 g->private_data = &tape->driver;
2691 drive->driver_data = tape;
2693 mutex_lock(&idetape_ref_mutex);
2694 for (minor = 0; idetape_devs[minor]; minor++)
2696 idetape_devs[minor] = tape;
2697 mutex_unlock(&idetape_ref_mutex);
2699 idetape_setup(drive, tape, minor);
2701 device_create_drvdata(idetape_sysfs_class, &drive->gendev,
2702 MKDEV(IDETAPE_MAJOR, minor), NULL,
2704 device_create_drvdata(idetape_sysfs_class, &drive->gendev,
2705 MKDEV(IDETAPE_MAJOR, minor + 128), NULL,
2708 g->fops = &idetape_block_ops;
2709 ide_register_region(g);
2719 static void __exit idetape_exit(void)
2721 driver_unregister(&idetape_driver.gen_driver);
2722 class_destroy(idetape_sysfs_class);
2723 unregister_chrdev(IDETAPE_MAJOR, "ht");
2726 static int __init idetape_init(void)
2729 idetape_sysfs_class = class_create(THIS_MODULE, "ide_tape");
2730 if (IS_ERR(idetape_sysfs_class)) {
2731 idetape_sysfs_class = NULL;
2732 printk(KERN_ERR "Unable to create sysfs class for ide tapes\n");
2737 if (register_chrdev(IDETAPE_MAJOR, "ht", &idetape_fops)) {
2738 printk(KERN_ERR "ide-tape: Failed to register chrdev"
2741 goto out_free_class;
2744 error = driver_register(&idetape_driver.gen_driver);
2746 goto out_free_driver;
2751 driver_unregister(&idetape_driver.gen_driver);
2753 class_destroy(idetape_sysfs_class);
2758 MODULE_ALIAS("ide:*m-tape*");
2759 module_init(idetape_init);
2760 module_exit(idetape_exit);
2761 MODULE_ALIAS_CHARDEV_MAJOR(IDETAPE_MAJOR);
2762 MODULE_DESCRIPTION("ATAPI Streaming TAPE Driver");
2763 MODULE_LICENSE("GPL");