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->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->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(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(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;
588 kfree(tape->merge_bh);
591 static int idetape_end_request(ide_drive_t *drive, int uptodate, int nr_sects)
593 struct request *rq = HWGROUP(drive)->rq;
594 idetape_tape_t *tape = drive->driver_data;
598 debug_log(DBG_PROCS, "Enter %s\n", __func__);
601 case 0: error = IDETAPE_ERROR_GENERAL; break;
602 case 1: error = 0; break;
603 default: error = uptodate;
607 tape->failed_pc = NULL;
609 if (!blk_special_request(rq)) {
610 ide_end_request(drive, uptodate, nr_sects);
614 spin_lock_irqsave(&tape->lock, flags);
616 ide_end_drive_cmd(drive, 0, 0);
618 spin_unlock_irqrestore(&tape->lock, flags);
622 static void ide_tape_callback(ide_drive_t *drive)
624 idetape_tape_t *tape = drive->driver_data;
625 struct ide_atapi_pc *pc = tape->pc;
626 int uptodate = pc->error ? 0 : 1;
628 debug_log(DBG_PROCS, "Enter %s\n", __func__);
630 if (tape->failed_pc == pc)
631 tape->failed_pc = NULL;
633 if (pc->c[0] == REQUEST_SENSE) {
635 idetape_analyze_error(drive, pc->buf);
637 printk(KERN_ERR "ide-tape: Error in REQUEST SENSE "
638 "itself - Aborting request!\n");
639 } else if (pc->c[0] == READ_6 || pc->c[0] == WRITE_6) {
640 struct request *rq = drive->hwif->hwgroup->rq;
641 int blocks = pc->xferred / tape->blk_size;
643 tape->avg_size += blocks * tape->blk_size;
645 if (time_after_eq(jiffies, tape->avg_time + HZ)) {
646 tape->avg_speed = tape->avg_size * HZ /
647 (jiffies - tape->avg_time) / 1024;
649 tape->avg_time = jiffies;
652 tape->first_frame += blocks;
653 rq->current_nr_sectors -= blocks;
656 uptodate = pc->error;
657 } else if (pc->c[0] == READ_POSITION && uptodate) {
658 u8 *readpos = tape->pc->buf;
660 debug_log(DBG_SENSE, "BOP - %s\n",
661 (readpos[0] & 0x80) ? "Yes" : "No");
662 debug_log(DBG_SENSE, "EOP - %s\n",
663 (readpos[0] & 0x40) ? "Yes" : "No");
665 if (readpos[0] & 0x4) {
666 printk(KERN_INFO "ide-tape: Block location is unknown"
668 clear_bit(IDETAPE_FLAG_ADDRESS_VALID, &tape->flags);
671 debug_log(DBG_SENSE, "Block Location - %u\n",
672 be32_to_cpu(*(u32 *)&readpos[4]));
674 tape->partition = readpos[1];
675 tape->first_frame = be32_to_cpu(*(u32 *)&readpos[4]);
676 set_bit(IDETAPE_FLAG_ADDRESS_VALID, &tape->flags);
680 idetape_end_request(drive, uptodate, 0);
683 static void idetape_init_pc(struct ide_atapi_pc *pc)
685 memset(pc->c, 0, 12);
689 pc->buf = pc->pc_buf;
690 pc->buf_size = IDETAPE_PC_BUFFER_SIZE;
693 pc->callback = ide_tape_callback;
696 static void idetape_create_request_sense_cmd(struct ide_atapi_pc *pc)
699 pc->c[0] = REQUEST_SENSE;
704 static void idetape_init_rq(struct request *rq, u8 cmd)
706 blk_rq_init(NULL, rq);
707 rq->cmd_type = REQ_TYPE_SPECIAL;
712 * Generate a new packet command request in front of the request queue, before
713 * the current request, so that it will be processed immediately, on the next
714 * pass through the driver. The function below is called from the request
715 * handling part of the driver (the "bottom" part). Safe storage for the request
716 * should be allocated with ide_tape_next_{pc,rq}_storage() prior to that.
718 * Memory for those requests is pre-allocated at initialization time, and is
719 * limited to IDETAPE_PC_STACK requests. We assume that we have enough space for
720 * the maximum possible number of inter-dependent packet commands.
722 * The higher level of the driver - The ioctl handler and the character device
723 * handling functions should queue request to the lower level part and wait for
724 * their completion using idetape_queue_pc_tail or idetape_queue_rw_tail.
726 static void idetape_queue_pc_head(ide_drive_t *drive, struct ide_atapi_pc *pc,
729 struct ide_tape_obj *tape = drive->driver_data;
731 idetape_init_rq(rq, REQ_IDETAPE_PC1);
732 rq->cmd_flags |= REQ_PREEMPT;
733 rq->buffer = (char *) pc;
734 rq->rq_disk = tape->disk;
735 ide_do_drive_cmd(drive, rq);
739 * idetape_retry_pc is called when an error was detected during the
740 * last packet command. We queue a request sense packet command in
741 * the head of the request list.
743 static void idetape_retry_pc(ide_drive_t *drive)
745 idetape_tape_t *tape = drive->driver_data;
746 struct ide_atapi_pc *pc;
749 (void)ide_read_error(drive);
750 pc = idetape_next_pc_storage(drive);
751 rq = idetape_next_rq_storage(drive);
752 idetape_create_request_sense_cmd(pc);
753 set_bit(IDETAPE_FLAG_IGNORE_DSC, &tape->flags);
754 idetape_queue_pc_head(drive, pc, rq);
758 * Postpone the current request so that ide.c will be able to service requests
759 * from another device on the same hwgroup while we are polling for DSC.
761 static void idetape_postpone_request(ide_drive_t *drive)
763 idetape_tape_t *tape = drive->driver_data;
765 debug_log(DBG_PROCS, "Enter %s\n", __func__);
767 tape->postponed_rq = HWGROUP(drive)->rq;
768 ide_stall_queue(drive, tape->dsc_poll_freq);
771 static void ide_tape_handle_dsc(ide_drive_t *drive)
773 idetape_tape_t *tape = drive->driver_data;
775 /* Media access command */
776 tape->dsc_polling_start = jiffies;
777 tape->dsc_poll_freq = IDETAPE_DSC_MA_FAST;
778 tape->dsc_timeout = jiffies + IDETAPE_DSC_MA_TIMEOUT;
779 /* Allow ide.c to handle other requests */
780 idetape_postpone_request(drive);
783 typedef void idetape_io_buf(ide_drive_t *, struct ide_atapi_pc *, unsigned int);
786 * This is the usual interrupt handler which will be called during a packet
787 * command. We will transfer some of the data (as requested by the drive) and
788 * will re-point interrupt handler to us. When data transfer is finished, we
789 * will act according to the algorithm described before
792 static ide_startstop_t idetape_pc_intr(ide_drive_t *drive)
794 ide_hwif_t *hwif = drive->hwif;
795 idetape_tape_t *tape = drive->driver_data;
796 struct ide_atapi_pc *pc = tape->pc;
797 xfer_func_t *xferfunc;
798 idetape_io_buf *iobuf;
803 debug_log(DBG_PROCS, "Enter %s - interrupt handler\n", __func__);
805 /* Clear the interrupt */
806 stat = ide_read_status(drive);
808 if (pc->flags & PC_FLAG_DMA_IN_PROGRESS) {
809 if (hwif->dma_ops->dma_end(drive) || (stat & ERR_STAT)) {
810 pc->flags |= PC_FLAG_DMA_ERROR;
812 pc->xferred = pc->req_xfer;
813 idetape_update_buffers(pc);
815 debug_log(DBG_PROCS, "DMA finished\n");
819 /* No more interrupts */
820 if ((stat & DRQ_STAT) == 0) {
821 debug_log(DBG_SENSE, "Packet command completed, %d bytes"
822 " transferred\n", pc->xferred);
824 pc->flags &= ~PC_FLAG_DMA_IN_PROGRESS;
825 local_irq_enable_in_hardirq();
827 if ((stat & ERR_STAT) && pc->c[0] == REQUEST_SENSE)
829 if ((stat & ERR_STAT) || (pc->flags & PC_FLAG_DMA_ERROR)) {
831 debug_log(DBG_ERR, "%s: I/O error\n", tape->name);
833 if (pc->c[0] == REQUEST_SENSE) {
834 printk(KERN_ERR "%s: I/O error in request sense"
835 " command\n", drive->name);
836 return ide_do_reset(drive);
838 debug_log(DBG_ERR, "[cmd %x]: check condition\n",
841 /* Retry operation */
842 idetape_retry_pc(drive);
846 if ((pc->flags & PC_FLAG_WAIT_FOR_DSC) &&
847 (stat & SEEK_STAT) == 0) {
848 ide_tape_handle_dsc(drive);
851 /* Command finished - Call the callback function */
856 if (pc->flags & PC_FLAG_DMA_IN_PROGRESS) {
857 pc->flags &= ~PC_FLAG_DMA_IN_PROGRESS;
858 printk(KERN_ERR "%s: The device wants to issue more interrupts "
859 "in DMA mode\n", drive->name);
861 return ide_do_reset(drive);
863 /* Get the number of bytes to transfer on this interrupt. */
864 bcount = (hwif->INB(hwif->io_ports.lbah_addr) << 8) |
865 hwif->INB(hwif->io_ports.lbam_addr);
867 ireason = hwif->INB(hwif->io_ports.nsect_addr);
870 printk(KERN_ERR "%s: CoD != 0 in %s\n", drive->name, __func__);
871 return ide_do_reset(drive);
873 if (((ireason & IO) == IO) == !!(pc->flags & PC_FLAG_WRITING)) {
874 /* Hopefully, we will never get here */
875 printk(KERN_ERR "%s: We wanted to %s, but the device wants us "
876 "to %s!\n", drive->name,
877 (ireason & IO) ? "Write" : "Read",
878 (ireason & IO) ? "Read" : "Write");
879 return ide_do_reset(drive);
881 if (!(pc->flags & PC_FLAG_WRITING)) {
882 /* Reading - Check that we have enough space */
883 temp = pc->xferred + bcount;
884 if (temp > pc->req_xfer) {
885 if (temp > pc->buf_size) {
886 printk(KERN_ERR "%s: The device wants to send "
887 "us more data than expected - "
890 ide_pad_transfer(drive, 0, bcount);
891 ide_set_handler(drive, &idetape_pc_intr,
892 IDETAPE_WAIT_CMD, NULL);
895 debug_log(DBG_SENSE, "The device wants to send us more "
896 "data than expected - allowing transfer\n");
898 iobuf = &idetape_input_buffers;
899 xferfunc = hwif->input_data;
901 iobuf = &idetape_output_buffers;
902 xferfunc = hwif->output_data;
906 iobuf(drive, pc, bcount);
908 xferfunc(drive, NULL, pc->cur_pos, bcount);
910 /* Update the current position */
911 pc->xferred += bcount;
912 pc->cur_pos += bcount;
914 debug_log(DBG_SENSE, "[cmd %x] transferred %d bytes on that intr.\n",
917 /* And set the interrupt handler again */
918 ide_set_handler(drive, &idetape_pc_intr, IDETAPE_WAIT_CMD, NULL);
923 * Packet Command Interface
925 * The current Packet Command is available in tape->pc, and will not change
926 * until we finish handling it. Each packet command is associated with a
927 * callback function that will be called when the command is finished.
929 * The handling will be done in three stages:
931 * 1. idetape_issue_pc will send the packet command to the drive, and will set
932 * the interrupt handler to idetape_pc_intr.
934 * 2. On each interrupt, idetape_pc_intr will be called. This step will be
935 * repeated until the device signals us that no more interrupts will be issued.
937 * 3. ATAPI Tape media access commands have immediate status with a delayed
938 * process. In case of a successful initiation of a media access packet command,
939 * the DSC bit will be set when the actual execution of the command is finished.
940 * Since the tape drive will not issue an interrupt, we have to poll for this
941 * event. In this case, we define the request as "low priority request" by
942 * setting rq_status to IDETAPE_RQ_POSTPONED, set a timer to poll for DSC and
945 * ide.c will then give higher priority to requests which originate from the
946 * other device, until will change rq_status to RQ_ACTIVE.
948 * 4. When the packet command is finished, it will be checked for errors.
950 * 5. In case an error was found, we queue a request sense packet command in
951 * front of the request queue and retry the operation up to
952 * IDETAPE_MAX_PC_RETRIES times.
954 * 6. In case no error was found, or we decided to give up and not to retry
955 * again, the callback function will be called and then we will handle the next
958 static ide_startstop_t idetape_transfer_pc(ide_drive_t *drive)
960 idetape_tape_t *tape = drive->driver_data;
962 return ide_transfer_pc(drive, tape->pc, idetape_pc_intr,
963 IDETAPE_WAIT_CMD, NULL);
966 static ide_startstop_t idetape_issue_pc(ide_drive_t *drive,
967 struct ide_atapi_pc *pc)
969 idetape_tape_t *tape = drive->driver_data;
971 if (tape->pc->c[0] == REQUEST_SENSE &&
972 pc->c[0] == REQUEST_SENSE) {
973 printk(KERN_ERR "ide-tape: possible ide-tape.c bug - "
974 "Two request sense in serial were issued\n");
977 if (tape->failed_pc == NULL && pc->c[0] != REQUEST_SENSE)
978 tape->failed_pc = pc;
979 /* Set the current packet command */
982 if (pc->retries > IDETAPE_MAX_PC_RETRIES ||
983 (pc->flags & PC_FLAG_ABORT)) {
985 * We will "abort" retrying a packet command in case legitimate
986 * error code was received (crossing a filemark, or end of the
987 * media, for example).
989 if (!(pc->flags & PC_FLAG_ABORT)) {
990 if (!(pc->c[0] == TEST_UNIT_READY &&
991 tape->sense_key == 2 && tape->asc == 4 &&
992 (tape->ascq == 1 || tape->ascq == 8))) {
993 printk(KERN_ERR "ide-tape: %s: I/O error, "
994 "pc = %2x, key = %2x, "
995 "asc = %2x, ascq = %2x\n",
996 tape->name, pc->c[0],
997 tape->sense_key, tape->asc,
1001 pc->error = IDETAPE_ERROR_GENERAL;
1003 tape->failed_pc = NULL;
1004 pc->callback(drive);
1007 debug_log(DBG_SENSE, "Retry #%d, cmd = %02X\n", pc->retries, pc->c[0]);
1011 return ide_issue_pc(drive, pc, idetape_transfer_pc,
1012 IDETAPE_WAIT_CMD, NULL);
1015 /* A mode sense command is used to "sense" tape parameters. */
1016 static void idetape_create_mode_sense_cmd(struct ide_atapi_pc *pc, u8 page_code)
1018 idetape_init_pc(pc);
1019 pc->c[0] = MODE_SENSE;
1020 if (page_code != IDETAPE_BLOCK_DESCRIPTOR)
1021 /* DBD = 1 - Don't return block descriptors */
1023 pc->c[2] = page_code;
1025 * Changed pc->c[3] to 0 (255 will at best return unused info).
1027 * For SCSI this byte is defined as subpage instead of high byte
1028 * of length and some IDE drives seem to interpret it this way
1029 * and return an error when 255 is used.
1032 /* We will just discard data in that case */
1034 if (page_code == IDETAPE_BLOCK_DESCRIPTOR)
1036 else if (page_code == IDETAPE_CAPABILITIES_PAGE)
1042 static ide_startstop_t idetape_media_access_finished(ide_drive_t *drive)
1044 idetape_tape_t *tape = drive->driver_data;
1045 struct ide_atapi_pc *pc = tape->pc;
1048 stat = ide_read_status(drive);
1050 if (stat & SEEK_STAT) {
1051 if (stat & ERR_STAT) {
1052 /* Error detected */
1053 if (pc->c[0] != TEST_UNIT_READY)
1054 printk(KERN_ERR "ide-tape: %s: I/O error, ",
1056 /* Retry operation */
1057 idetape_retry_pc(drive);
1062 pc->error = IDETAPE_ERROR_GENERAL;
1063 tape->failed_pc = NULL;
1065 pc->callback(drive);
1069 static void idetape_create_read_cmd(idetape_tape_t *tape,
1070 struct ide_atapi_pc *pc,
1071 unsigned int length, struct idetape_bh *bh)
1073 idetape_init_pc(pc);
1075 put_unaligned(cpu_to_be32(length), (unsigned int *) &pc->c[1]);
1078 atomic_set(&bh->b_count, 0);
1080 pc->buf_size = length * tape->blk_size;
1081 pc->req_xfer = pc->buf_size;
1082 if (pc->req_xfer == tape->buffer_size)
1083 pc->flags |= PC_FLAG_DMA_OK;
1086 static void idetape_create_write_cmd(idetape_tape_t *tape,
1087 struct ide_atapi_pc *pc,
1088 unsigned int length, struct idetape_bh *bh)
1090 idetape_init_pc(pc);
1092 put_unaligned(cpu_to_be32(length), (unsigned int *) &pc->c[1]);
1094 pc->flags |= PC_FLAG_WRITING;
1096 pc->b_data = bh->b_data;
1097 pc->b_count = atomic_read(&bh->b_count);
1099 pc->buf_size = length * tape->blk_size;
1100 pc->req_xfer = pc->buf_size;
1101 if (pc->req_xfer == tape->buffer_size)
1102 pc->flags |= PC_FLAG_DMA_OK;
1105 static ide_startstop_t idetape_do_request(ide_drive_t *drive,
1106 struct request *rq, sector_t block)
1108 idetape_tape_t *tape = drive->driver_data;
1109 struct ide_atapi_pc *pc = NULL;
1110 struct request *postponed_rq = tape->postponed_rq;
1113 debug_log(DBG_SENSE, "sector: %ld, nr_sectors: %ld,"
1114 " current_nr_sectors: %d\n",
1115 rq->sector, rq->nr_sectors, rq->current_nr_sectors);
1117 if (!blk_special_request(rq)) {
1118 /* We do not support buffer cache originated requests. */
1119 printk(KERN_NOTICE "ide-tape: %s: Unsupported request in "
1120 "request queue (%d)\n", drive->name, rq->cmd_type);
1121 ide_end_request(drive, 0, 0);
1125 /* Retry a failed packet command */
1126 if (tape->failed_pc && tape->pc->c[0] == REQUEST_SENSE) {
1127 pc = tape->failed_pc;
1131 if (postponed_rq != NULL)
1132 if (rq != postponed_rq) {
1133 printk(KERN_ERR "ide-tape: ide-tape.c bug - "
1134 "Two DSC requests were queued\n");
1135 idetape_end_request(drive, 0, 0);
1139 tape->postponed_rq = NULL;
1142 * If the tape is still busy, postpone our request and service
1143 * the other device meanwhile.
1145 stat = ide_read_status(drive);
1147 if (!drive->dsc_overlap && !(rq->cmd[0] & REQ_IDETAPE_PC2))
1148 set_bit(IDETAPE_FLAG_IGNORE_DSC, &tape->flags);
1150 if (drive->post_reset == 1) {
1151 set_bit(IDETAPE_FLAG_IGNORE_DSC, &tape->flags);
1152 drive->post_reset = 0;
1155 if (!test_and_clear_bit(IDETAPE_FLAG_IGNORE_DSC, &tape->flags) &&
1156 (stat & SEEK_STAT) == 0) {
1157 if (postponed_rq == NULL) {
1158 tape->dsc_polling_start = jiffies;
1159 tape->dsc_poll_freq = tape->best_dsc_rw_freq;
1160 tape->dsc_timeout = jiffies + IDETAPE_DSC_RW_TIMEOUT;
1161 } else if (time_after(jiffies, tape->dsc_timeout)) {
1162 printk(KERN_ERR "ide-tape: %s: DSC timeout\n",
1164 if (rq->cmd[0] & REQ_IDETAPE_PC2) {
1165 idetape_media_access_finished(drive);
1168 return ide_do_reset(drive);
1170 } else if (time_after(jiffies,
1171 tape->dsc_polling_start +
1172 IDETAPE_DSC_MA_THRESHOLD))
1173 tape->dsc_poll_freq = IDETAPE_DSC_MA_SLOW;
1174 idetape_postpone_request(drive);
1177 if (rq->cmd[0] & REQ_IDETAPE_READ) {
1178 pc = idetape_next_pc_storage(drive);
1179 idetape_create_read_cmd(tape, pc, rq->current_nr_sectors,
1180 (struct idetape_bh *)rq->special);
1183 if (rq->cmd[0] & REQ_IDETAPE_WRITE) {
1184 pc = idetape_next_pc_storage(drive);
1185 idetape_create_write_cmd(tape, pc, rq->current_nr_sectors,
1186 (struct idetape_bh *)rq->special);
1189 if (rq->cmd[0] & REQ_IDETAPE_PC1) {
1190 pc = (struct ide_atapi_pc *) rq->buffer;
1191 rq->cmd[0] &= ~(REQ_IDETAPE_PC1);
1192 rq->cmd[0] |= REQ_IDETAPE_PC2;
1195 if (rq->cmd[0] & REQ_IDETAPE_PC2) {
1196 idetape_media_access_finished(drive);
1201 if (test_bit(IDETAPE_FLAG_DRQ_INTERRUPT, &tape->flags))
1202 pc->flags |= PC_FLAG_DRQ_INTERRUPT;
1204 return idetape_issue_pc(drive, pc);
1208 * The function below uses __get_free_pages to allocate a data buffer of size
1209 * tape->buffer_size (or a bit more). We attempt to combine sequential pages as
1212 * It returns a pointer to the newly allocated buffer, or NULL in case of
1215 static struct idetape_bh *ide_tape_kmalloc_buffer(idetape_tape_t *tape,
1216 int full, int clear)
1218 struct idetape_bh *prev_bh, *bh, *merge_bh;
1219 int pages = tape->pages_per_buffer;
1220 unsigned int order, b_allocd;
1221 char *b_data = NULL;
1223 merge_bh = kmalloc(sizeof(struct idetape_bh), GFP_KERNEL);
1228 order = fls(pages) - 1;
1229 bh->b_data = (char *) __get_free_pages(GFP_KERNEL, order);
1232 b_allocd = (1 << order) * PAGE_SIZE;
1236 memset(bh->b_data, 0, b_allocd);
1237 bh->b_reqnext = NULL;
1238 bh->b_size = b_allocd;
1239 atomic_set(&bh->b_count, full ? bh->b_size : 0);
1242 order = fls(pages) - 1;
1243 b_data = (char *) __get_free_pages(GFP_KERNEL, order);
1246 b_allocd = (1 << order) * PAGE_SIZE;
1249 memset(b_data, 0, b_allocd);
1251 /* newly allocated page frames below buffer header or ...*/
1252 if (bh->b_data == b_data + b_allocd) {
1253 bh->b_size += b_allocd;
1254 bh->b_data -= b_allocd;
1256 atomic_add(b_allocd, &bh->b_count);
1259 /* they are above the header */
1260 if (b_data == bh->b_data + bh->b_size) {
1261 bh->b_size += b_allocd;
1263 atomic_add(b_allocd, &bh->b_count);
1267 bh = kmalloc(sizeof(struct idetape_bh), GFP_KERNEL);
1269 free_pages((unsigned long) b_data, order);
1272 bh->b_reqnext = NULL;
1273 bh->b_data = b_data;
1274 bh->b_size = b_allocd;
1275 atomic_set(&bh->b_count, full ? bh->b_size : 0);
1276 prev_bh->b_reqnext = bh;
1281 bh->b_size -= tape->excess_bh_size;
1283 atomic_sub(tape->excess_bh_size, &bh->b_count);
1286 ide_tape_kfree_buffer(tape);
1290 static int idetape_copy_stage_from_user(idetape_tape_t *tape,
1291 const char __user *buf, int n)
1293 struct idetape_bh *bh = tape->bh;
1299 printk(KERN_ERR "ide-tape: bh == NULL in %s\n",
1303 count = min((unsigned int)
1304 (bh->b_size - atomic_read(&bh->b_count)),
1306 if (copy_from_user(bh->b_data + atomic_read(&bh->b_count), buf,
1310 atomic_add(count, &bh->b_count);
1312 if (atomic_read(&bh->b_count) == bh->b_size) {
1315 atomic_set(&bh->b_count, 0);
1322 static int idetape_copy_stage_to_user(idetape_tape_t *tape, char __user *buf,
1325 struct idetape_bh *bh = tape->bh;
1331 printk(KERN_ERR "ide-tape: bh == NULL in %s\n",
1335 count = min(tape->b_count, n);
1336 if (copy_to_user(buf, tape->b_data, count))
1339 tape->b_data += count;
1340 tape->b_count -= count;
1342 if (!tape->b_count) {
1346 tape->b_data = bh->b_data;
1347 tape->b_count = atomic_read(&bh->b_count);
1354 static void idetape_init_merge_buffer(idetape_tape_t *tape)
1356 struct idetape_bh *bh = tape->merge_bh;
1357 tape->bh = tape->merge_bh;
1359 if (tape->chrdev_dir == IDETAPE_DIR_WRITE)
1360 atomic_set(&bh->b_count, 0);
1362 tape->b_data = bh->b_data;
1363 tape->b_count = atomic_read(&bh->b_count);
1368 * Write a filemark if write_filemark=1. Flush the device buffers without
1369 * writing a filemark otherwise.
1371 static void idetape_create_write_filemark_cmd(ide_drive_t *drive,
1372 struct ide_atapi_pc *pc, int write_filemark)
1374 idetape_init_pc(pc);
1375 pc->c[0] = WRITE_FILEMARKS;
1376 pc->c[4] = write_filemark;
1377 pc->flags |= PC_FLAG_WAIT_FOR_DSC;
1380 static void idetape_create_test_unit_ready_cmd(struct ide_atapi_pc *pc)
1382 idetape_init_pc(pc);
1383 pc->c[0] = TEST_UNIT_READY;
1387 * We add a special packet command request to the tail of the request queue, and
1388 * wait for it to be serviced. This is not to be called from within the request
1389 * handling part of the driver! We allocate here data on the stack and it is
1390 * valid until the request is finished. This is not the case for the bottom part
1391 * of the driver, where we are always leaving the functions to wait for an
1392 * interrupt or a timer event.
1394 * From the bottom part of the driver, we should allocate safe memory using
1395 * idetape_next_pc_storage() and ide_tape_next_rq_storage(), and add the request
1396 * to the request list without waiting for it to be serviced! In that case, we
1397 * usually use idetape_queue_pc_head().
1399 static int idetape_queue_pc_tail(ide_drive_t *drive, struct ide_atapi_pc *pc)
1401 struct ide_tape_obj *tape = drive->driver_data;
1405 rq = blk_get_request(drive->queue, READ, __GFP_WAIT);
1406 rq->cmd_type = REQ_TYPE_SPECIAL;
1407 rq->cmd[0] = REQ_IDETAPE_PC1;
1408 rq->buffer = (char *)pc;
1409 error = blk_execute_rq(drive->queue, tape->disk, rq, 0);
1410 blk_put_request(rq);
1414 static void idetape_create_load_unload_cmd(ide_drive_t *drive,
1415 struct ide_atapi_pc *pc, int cmd)
1417 idetape_init_pc(pc);
1418 pc->c[0] = START_STOP;
1420 pc->flags |= PC_FLAG_WAIT_FOR_DSC;
1423 static int idetape_wait_ready(ide_drive_t *drive, unsigned long timeout)
1425 idetape_tape_t *tape = drive->driver_data;
1426 struct ide_atapi_pc pc;
1427 int load_attempted = 0;
1429 /* Wait for the tape to become ready */
1430 set_bit(IDETAPE_FLAG_MEDIUM_PRESENT, &tape->flags);
1432 while (time_before(jiffies, timeout)) {
1433 idetape_create_test_unit_ready_cmd(&pc);
1434 if (!idetape_queue_pc_tail(drive, &pc))
1436 if ((tape->sense_key == 2 && tape->asc == 4 && tape->ascq == 2)
1437 || (tape->asc == 0x3A)) {
1441 idetape_create_load_unload_cmd(drive, &pc,
1442 IDETAPE_LU_LOAD_MASK);
1443 idetape_queue_pc_tail(drive, &pc);
1445 /* not about to be ready */
1446 } else if (!(tape->sense_key == 2 && tape->asc == 4 &&
1447 (tape->ascq == 1 || tape->ascq == 8)))
1454 static int idetape_flush_tape_buffers(ide_drive_t *drive)
1456 struct ide_atapi_pc pc;
1459 idetape_create_write_filemark_cmd(drive, &pc, 0);
1460 rc = idetape_queue_pc_tail(drive, &pc);
1463 idetape_wait_ready(drive, 60 * 5 * HZ);
1467 static void idetape_create_read_position_cmd(struct ide_atapi_pc *pc)
1469 idetape_init_pc(pc);
1470 pc->c[0] = READ_POSITION;
1474 static int idetape_read_position(ide_drive_t *drive)
1476 idetape_tape_t *tape = drive->driver_data;
1477 struct ide_atapi_pc pc;
1480 debug_log(DBG_PROCS, "Enter %s\n", __func__);
1482 idetape_create_read_position_cmd(&pc);
1483 if (idetape_queue_pc_tail(drive, &pc))
1485 position = tape->first_frame;
1489 static void idetape_create_locate_cmd(ide_drive_t *drive,
1490 struct ide_atapi_pc *pc,
1491 unsigned int block, u8 partition, int skip)
1493 idetape_init_pc(pc);
1494 pc->c[0] = POSITION_TO_ELEMENT;
1496 put_unaligned(cpu_to_be32(block), (unsigned int *) &pc->c[3]);
1497 pc->c[8] = partition;
1498 pc->flags |= PC_FLAG_WAIT_FOR_DSC;
1501 static int idetape_create_prevent_cmd(ide_drive_t *drive,
1502 struct ide_atapi_pc *pc, int prevent)
1504 idetape_tape_t *tape = drive->driver_data;
1506 /* device supports locking according to capabilities page */
1507 if (!(tape->caps[6] & 0x01))
1510 idetape_init_pc(pc);
1511 pc->c[0] = ALLOW_MEDIUM_REMOVAL;
1516 static void __ide_tape_discard_merge_buffer(ide_drive_t *drive)
1518 idetape_tape_t *tape = drive->driver_data;
1520 if (tape->chrdev_dir != IDETAPE_DIR_READ)
1523 clear_bit(IDETAPE_FLAG_FILEMARK, &tape->flags);
1524 tape->merge_bh_size = 0;
1525 if (tape->merge_bh != NULL) {
1526 ide_tape_kfree_buffer(tape);
1527 tape->merge_bh = NULL;
1530 tape->chrdev_dir = IDETAPE_DIR_NONE;
1534 * Position the tape to the requested block using the LOCATE packet command.
1535 * A READ POSITION command is then issued to check where we are positioned. Like
1536 * all higher level operations, we queue the commands at the tail of the request
1537 * queue and wait for their completion.
1539 static int idetape_position_tape(ide_drive_t *drive, unsigned int block,
1540 u8 partition, int skip)
1542 idetape_tape_t *tape = drive->driver_data;
1544 struct ide_atapi_pc pc;
1546 if (tape->chrdev_dir == IDETAPE_DIR_READ)
1547 __ide_tape_discard_merge_buffer(drive);
1548 idetape_wait_ready(drive, 60 * 5 * HZ);
1549 idetape_create_locate_cmd(drive, &pc, block, partition, skip);
1550 retval = idetape_queue_pc_tail(drive, &pc);
1554 idetape_create_read_position_cmd(&pc);
1555 return (idetape_queue_pc_tail(drive, &pc));
1558 static void ide_tape_discard_merge_buffer(ide_drive_t *drive,
1559 int restore_position)
1561 idetape_tape_t *tape = drive->driver_data;
1564 __ide_tape_discard_merge_buffer(drive);
1565 if (restore_position) {
1566 position = idetape_read_position(drive);
1567 seek = position > 0 ? position : 0;
1568 if (idetape_position_tape(drive, seek, 0, 0)) {
1569 printk(KERN_INFO "ide-tape: %s: position_tape failed in"
1570 " %s\n", tape->name, __func__);
1577 * Generate a read/write request for the block device interface and wait for it
1580 static int idetape_queue_rw_tail(ide_drive_t *drive, int cmd, int blocks,
1581 struct idetape_bh *bh)
1583 idetape_tape_t *tape = drive->driver_data;
1587 debug_log(DBG_SENSE, "%s: cmd=%d\n", __func__, cmd);
1589 rq = blk_get_request(drive->queue, READ, __GFP_WAIT);
1590 rq->cmd_type = REQ_TYPE_SPECIAL;
1592 rq->rq_disk = tape->disk;
1593 rq->special = (void *)bh;
1594 rq->sector = tape->first_frame;
1595 rq->nr_sectors = blocks;
1596 rq->current_nr_sectors = blocks;
1597 blk_execute_rq(drive->queue, tape->disk, rq, 0);
1599 errors = rq->errors;
1600 ret = tape->blk_size * (blocks - rq->current_nr_sectors);
1601 blk_put_request(rq);
1603 if ((cmd & (REQ_IDETAPE_READ | REQ_IDETAPE_WRITE)) == 0)
1607 idetape_init_merge_buffer(tape);
1608 if (errors == IDETAPE_ERROR_GENERAL)
1613 static void idetape_create_inquiry_cmd(struct ide_atapi_pc *pc)
1615 idetape_init_pc(pc);
1621 static void idetape_create_rewind_cmd(ide_drive_t *drive,
1622 struct ide_atapi_pc *pc)
1624 idetape_init_pc(pc);
1625 pc->c[0] = REZERO_UNIT;
1626 pc->flags |= PC_FLAG_WAIT_FOR_DSC;
1629 static void idetape_create_erase_cmd(struct ide_atapi_pc *pc)
1631 idetape_init_pc(pc);
1634 pc->flags |= PC_FLAG_WAIT_FOR_DSC;
1637 static void idetape_create_space_cmd(struct ide_atapi_pc *pc, int count, u8 cmd)
1639 idetape_init_pc(pc);
1641 put_unaligned(cpu_to_be32(count), (unsigned int *) &pc->c[1]);
1643 pc->flags |= PC_FLAG_WAIT_FOR_DSC;
1646 /* Queue up a character device originated write request. */
1647 static int idetape_add_chrdev_write_request(ide_drive_t *drive, int blocks)
1649 idetape_tape_t *tape = drive->driver_data;
1651 debug_log(DBG_CHRDEV, "Enter %s\n", __func__);
1653 return idetape_queue_rw_tail(drive, REQ_IDETAPE_WRITE,
1654 blocks, tape->merge_bh);
1657 static void ide_tape_flush_merge_buffer(ide_drive_t *drive)
1659 idetape_tape_t *tape = drive->driver_data;
1661 struct idetape_bh *bh;
1663 if (tape->chrdev_dir != IDETAPE_DIR_WRITE) {
1664 printk(KERN_ERR "ide-tape: bug: Trying to empty merge buffer"
1665 " but we are not writing.\n");
1668 if (tape->merge_bh_size > tape->buffer_size) {
1669 printk(KERN_ERR "ide-tape: bug: merge_buffer too big\n");
1670 tape->merge_bh_size = tape->buffer_size;
1672 if (tape->merge_bh_size) {
1673 blocks = tape->merge_bh_size / tape->blk_size;
1674 if (tape->merge_bh_size % tape->blk_size) {
1678 i = tape->blk_size - tape->merge_bh_size %
1680 bh = tape->bh->b_reqnext;
1682 atomic_set(&bh->b_count, 0);
1688 printk(KERN_INFO "ide-tape: bug,"
1692 min = min(i, (unsigned int)(bh->b_size -
1693 atomic_read(&bh->b_count)));
1694 memset(bh->b_data + atomic_read(&bh->b_count),
1696 atomic_add(min, &bh->b_count);
1701 (void) idetape_add_chrdev_write_request(drive, blocks);
1702 tape->merge_bh_size = 0;
1704 if (tape->merge_bh != NULL) {
1705 ide_tape_kfree_buffer(tape);
1706 tape->merge_bh = NULL;
1708 tape->chrdev_dir = IDETAPE_DIR_NONE;
1711 static int idetape_init_read(ide_drive_t *drive)
1713 idetape_tape_t *tape = drive->driver_data;
1716 /* Initialize read operation */
1717 if (tape->chrdev_dir != IDETAPE_DIR_READ) {
1718 if (tape->chrdev_dir == IDETAPE_DIR_WRITE) {
1719 ide_tape_flush_merge_buffer(drive);
1720 idetape_flush_tape_buffers(drive);
1722 if (tape->merge_bh || tape->merge_bh_size) {
1723 printk(KERN_ERR "ide-tape: merge_bh_size should be"
1725 tape->merge_bh_size = 0;
1727 tape->merge_bh = ide_tape_kmalloc_buffer(tape, 0, 0);
1728 if (!tape->merge_bh)
1730 tape->chrdev_dir = IDETAPE_DIR_READ;
1733 * Issue a read 0 command to ensure that DSC handshake is
1734 * switched from completion mode to buffer available mode.
1735 * No point in issuing this if DSC overlap isn't supported, some
1736 * drives (Seagate STT3401A) will return an error.
1738 if (drive->dsc_overlap) {
1739 bytes_read = idetape_queue_rw_tail(drive,
1740 REQ_IDETAPE_READ, 0,
1742 if (bytes_read < 0) {
1743 ide_tape_kfree_buffer(tape);
1744 tape->merge_bh = NULL;
1745 tape->chrdev_dir = IDETAPE_DIR_NONE;
1754 /* called from idetape_chrdev_read() to service a chrdev read request. */
1755 static int idetape_add_chrdev_read_request(ide_drive_t *drive, int blocks)
1757 idetape_tape_t *tape = drive->driver_data;
1759 debug_log(DBG_PROCS, "Enter %s, %d blocks\n", __func__, blocks);
1761 /* If we are at a filemark, return a read length of 0 */
1762 if (test_bit(IDETAPE_FLAG_FILEMARK, &tape->flags))
1765 idetape_init_read(drive);
1767 return idetape_queue_rw_tail(drive, REQ_IDETAPE_READ, blocks,
1771 static void idetape_pad_zeros(ide_drive_t *drive, int bcount)
1773 idetape_tape_t *tape = drive->driver_data;
1774 struct idetape_bh *bh;
1780 bh = tape->merge_bh;
1781 count = min(tape->buffer_size, bcount);
1783 blocks = count / tape->blk_size;
1785 atomic_set(&bh->b_count,
1786 min(count, (unsigned int)bh->b_size));
1787 memset(bh->b_data, 0, atomic_read(&bh->b_count));
1788 count -= atomic_read(&bh->b_count);
1791 idetape_queue_rw_tail(drive, REQ_IDETAPE_WRITE, blocks,
1797 * Rewinds the tape to the Beginning Of the current Partition (BOP). We
1798 * currently support only one partition.
1800 static int idetape_rewind_tape(ide_drive_t *drive)
1803 struct ide_atapi_pc pc;
1804 idetape_tape_t *tape;
1805 tape = drive->driver_data;
1807 debug_log(DBG_SENSE, "Enter %s\n", __func__);
1809 idetape_create_rewind_cmd(drive, &pc);
1810 retval = idetape_queue_pc_tail(drive, &pc);
1814 idetape_create_read_position_cmd(&pc);
1815 retval = idetape_queue_pc_tail(drive, &pc);
1821 /* mtio.h compatible commands should be issued to the chrdev interface. */
1822 static int idetape_blkdev_ioctl(ide_drive_t *drive, unsigned int cmd,
1825 idetape_tape_t *tape = drive->driver_data;
1826 void __user *argp = (void __user *)arg;
1828 struct idetape_config {
1829 int dsc_rw_frequency;
1830 int dsc_media_access_frequency;
1834 debug_log(DBG_PROCS, "Enter %s\n", __func__);
1838 if (copy_from_user(&config, argp, sizeof(config)))
1840 tape->best_dsc_rw_freq = config.dsc_rw_frequency;
1843 config.dsc_rw_frequency = (int) tape->best_dsc_rw_freq;
1844 config.nr_stages = 1;
1845 if (copy_to_user(argp, &config, sizeof(config)))
1854 static int idetape_space_over_filemarks(ide_drive_t *drive, short mt_op,
1857 idetape_tape_t *tape = drive->driver_data;
1858 struct ide_atapi_pc pc;
1859 int retval, count = 0;
1860 int sprev = !!(tape->caps[4] & 0x20);
1864 if (MTBSF == mt_op || MTBSFM == mt_op) {
1867 mt_count = -mt_count;
1870 if (tape->chrdev_dir == IDETAPE_DIR_READ) {
1871 tape->merge_bh_size = 0;
1872 if (test_and_clear_bit(IDETAPE_FLAG_FILEMARK, &tape->flags))
1874 ide_tape_discard_merge_buffer(drive, 0);
1880 idetape_create_space_cmd(&pc, mt_count - count,
1881 IDETAPE_SPACE_OVER_FILEMARK);
1882 return idetape_queue_pc_tail(drive, &pc);
1887 retval = idetape_space_over_filemarks(drive, MTFSF,
1891 count = (MTBSFM == mt_op ? 1 : -1);
1892 return idetape_space_over_filemarks(drive, MTFSF, count);
1894 printk(KERN_ERR "ide-tape: MTIO operation %d not supported\n",
1901 * Our character device read / write functions.
1903 * The tape is optimized to maximize throughput when it is transferring an
1904 * integral number of the "continuous transfer limit", which is a parameter of
1905 * the specific tape (26kB on my particular tape, 32kB for Onstream).
1907 * As of version 1.3 of the driver, the character device provides an abstract
1908 * continuous view of the media - any mix of block sizes (even 1 byte) on the
1909 * same backup/restore procedure is supported. The driver will internally
1910 * convert the requests to the recommended transfer unit, so that an unmatch
1911 * between the user's block size to the recommended size will only result in a
1912 * (slightly) increased driver overhead, but will no longer hit performance.
1913 * This is not applicable to Onstream.
1915 static ssize_t idetape_chrdev_read(struct file *file, char __user *buf,
1916 size_t count, loff_t *ppos)
1918 struct ide_tape_obj *tape = ide_tape_f(file);
1919 ide_drive_t *drive = tape->drive;
1920 ssize_t bytes_read, temp, actually_read = 0, rc;
1922 u16 ctl = *(u16 *)&tape->caps[12];
1924 debug_log(DBG_CHRDEV, "Enter %s, count %Zd\n", __func__, count);
1926 if (tape->chrdev_dir != IDETAPE_DIR_READ) {
1927 if (test_bit(IDETAPE_FLAG_DETECT_BS, &tape->flags))
1928 if (count > tape->blk_size &&
1929 (count % tape->blk_size) == 0)
1930 tape->user_bs_factor = count / tape->blk_size;
1932 rc = idetape_init_read(drive);
1937 if (tape->merge_bh_size) {
1938 actually_read = min((unsigned int)(tape->merge_bh_size),
1939 (unsigned int)count);
1940 if (idetape_copy_stage_to_user(tape, buf, actually_read))
1942 buf += actually_read;
1943 tape->merge_bh_size -= actually_read;
1944 count -= actually_read;
1946 while (count >= tape->buffer_size) {
1947 bytes_read = idetape_add_chrdev_read_request(drive, ctl);
1948 if (bytes_read <= 0)
1950 if (idetape_copy_stage_to_user(tape, buf, bytes_read))
1953 count -= bytes_read;
1954 actually_read += bytes_read;
1957 bytes_read = idetape_add_chrdev_read_request(drive, ctl);
1958 if (bytes_read <= 0)
1960 temp = min((unsigned long)count, (unsigned long)bytes_read);
1961 if (idetape_copy_stage_to_user(tape, buf, temp))
1963 actually_read += temp;
1964 tape->merge_bh_size = bytes_read-temp;
1967 if (!actually_read && test_bit(IDETAPE_FLAG_FILEMARK, &tape->flags)) {
1968 debug_log(DBG_SENSE, "%s: spacing over filemark\n", tape->name);
1970 idetape_space_over_filemarks(drive, MTFSF, 1);
1974 return ret ? ret : actually_read;
1977 static ssize_t idetape_chrdev_write(struct file *file, const char __user *buf,
1978 size_t count, loff_t *ppos)
1980 struct ide_tape_obj *tape = ide_tape_f(file);
1981 ide_drive_t *drive = tape->drive;
1982 ssize_t actually_written = 0;
1984 u16 ctl = *(u16 *)&tape->caps[12];
1986 /* The drive is write protected. */
1987 if (tape->write_prot)
1990 debug_log(DBG_CHRDEV, "Enter %s, count %Zd\n", __func__, count);
1992 /* Initialize write operation */
1993 if (tape->chrdev_dir != IDETAPE_DIR_WRITE) {
1994 if (tape->chrdev_dir == IDETAPE_DIR_READ)
1995 ide_tape_discard_merge_buffer(drive, 1);
1996 if (tape->merge_bh || tape->merge_bh_size) {
1997 printk(KERN_ERR "ide-tape: merge_bh_size "
1998 "should be 0 now\n");
1999 tape->merge_bh_size = 0;
2001 tape->merge_bh = ide_tape_kmalloc_buffer(tape, 0, 0);
2002 if (!tape->merge_bh)
2004 tape->chrdev_dir = IDETAPE_DIR_WRITE;
2005 idetape_init_merge_buffer(tape);
2008 * Issue a write 0 command to ensure that DSC handshake is
2009 * switched from completion mode to buffer available mode. No
2010 * point in issuing this if DSC overlap isn't supported, some
2011 * drives (Seagate STT3401A) will return an error.
2013 if (drive->dsc_overlap) {
2014 ssize_t retval = idetape_queue_rw_tail(drive,
2015 REQ_IDETAPE_WRITE, 0,
2018 ide_tape_kfree_buffer(tape);
2019 tape->merge_bh = NULL;
2020 tape->chrdev_dir = IDETAPE_DIR_NONE;
2027 if (tape->merge_bh_size) {
2028 if (tape->merge_bh_size >= tape->buffer_size) {
2029 printk(KERN_ERR "ide-tape: bug: merge buf too big\n");
2030 tape->merge_bh_size = 0;
2032 actually_written = min((unsigned int)
2033 (tape->buffer_size - tape->merge_bh_size),
2034 (unsigned int)count);
2035 if (idetape_copy_stage_from_user(tape, buf, actually_written))
2037 buf += actually_written;
2038 tape->merge_bh_size += actually_written;
2039 count -= actually_written;
2041 if (tape->merge_bh_size == tape->buffer_size) {
2043 tape->merge_bh_size = 0;
2044 retval = idetape_add_chrdev_write_request(drive, ctl);
2049 while (count >= tape->buffer_size) {
2051 if (idetape_copy_stage_from_user(tape, buf, tape->buffer_size))
2053 buf += tape->buffer_size;
2054 count -= tape->buffer_size;
2055 retval = idetape_add_chrdev_write_request(drive, ctl);
2056 actually_written += tape->buffer_size;
2061 actually_written += count;
2062 if (idetape_copy_stage_from_user(tape, buf, count))
2064 tape->merge_bh_size += count;
2066 return ret ? ret : actually_written;
2069 static int idetape_write_filemark(ide_drive_t *drive)
2071 struct ide_atapi_pc pc;
2073 /* Write a filemark */
2074 idetape_create_write_filemark_cmd(drive, &pc, 1);
2075 if (idetape_queue_pc_tail(drive, &pc)) {
2076 printk(KERN_ERR "ide-tape: Couldn't write a filemark\n");
2083 * Called from idetape_chrdev_ioctl when the general mtio MTIOCTOP ioctl is
2086 * Note: MTBSF and MTBSFM are not supported when the tape doesn't support
2087 * spacing over filemarks in the reverse direction. In this case, MTFSFM is also
2088 * usually not supported.
2090 * The following commands are currently not supported:
2092 * MTFSS, MTBSS, MTWSM, MTSETDENSITY, MTSETDRVBUFFER, MT_ST_BOOLEANS,
2093 * MT_ST_WRITE_THRESHOLD.
2095 static int idetape_mtioctop(ide_drive_t *drive, short mt_op, int mt_count)
2097 idetape_tape_t *tape = drive->driver_data;
2098 struct ide_atapi_pc pc;
2101 debug_log(DBG_ERR, "Handling MTIOCTOP ioctl: mt_op=%d, mt_count=%d\n",
2111 return idetape_space_over_filemarks(drive, mt_op, mt_count);
2118 if (tape->write_prot)
2120 ide_tape_discard_merge_buffer(drive, 1);
2121 for (i = 0; i < mt_count; i++) {
2122 retval = idetape_write_filemark(drive);
2128 ide_tape_discard_merge_buffer(drive, 0);
2129 if (idetape_rewind_tape(drive))
2133 ide_tape_discard_merge_buffer(drive, 0);
2134 idetape_create_load_unload_cmd(drive, &pc,
2135 IDETAPE_LU_LOAD_MASK);
2136 return idetape_queue_pc_tail(drive, &pc);
2140 * If door is locked, attempt to unlock before
2141 * attempting to eject.
2143 if (tape->door_locked) {
2144 if (idetape_create_prevent_cmd(drive, &pc, 0))
2145 if (!idetape_queue_pc_tail(drive, &pc))
2146 tape->door_locked = DOOR_UNLOCKED;
2148 ide_tape_discard_merge_buffer(drive, 0);
2149 idetape_create_load_unload_cmd(drive, &pc,
2150 !IDETAPE_LU_LOAD_MASK);
2151 retval = idetape_queue_pc_tail(drive, &pc);
2153 clear_bit(IDETAPE_FLAG_MEDIUM_PRESENT, &tape->flags);
2156 ide_tape_discard_merge_buffer(drive, 0);
2157 return idetape_flush_tape_buffers(drive);
2159 ide_tape_discard_merge_buffer(drive, 0);
2160 idetape_create_load_unload_cmd(drive, &pc,
2161 IDETAPE_LU_RETENSION_MASK | IDETAPE_LU_LOAD_MASK);
2162 return idetape_queue_pc_tail(drive, &pc);
2164 idetape_create_space_cmd(&pc, 0, IDETAPE_SPACE_TO_EOD);
2165 return idetape_queue_pc_tail(drive, &pc);
2167 (void)idetape_rewind_tape(drive);
2168 idetape_create_erase_cmd(&pc);
2169 return idetape_queue_pc_tail(drive, &pc);
2172 if (mt_count < tape->blk_size ||
2173 mt_count % tape->blk_size)
2175 tape->user_bs_factor = mt_count / tape->blk_size;
2176 clear_bit(IDETAPE_FLAG_DETECT_BS, &tape->flags);
2178 set_bit(IDETAPE_FLAG_DETECT_BS, &tape->flags);
2181 ide_tape_discard_merge_buffer(drive, 0);
2182 return idetape_position_tape(drive,
2183 mt_count * tape->user_bs_factor, tape->partition, 0);
2185 ide_tape_discard_merge_buffer(drive, 0);
2186 return idetape_position_tape(drive, 0, mt_count, 0);
2190 if (!idetape_create_prevent_cmd(drive, &pc, 1))
2192 retval = idetape_queue_pc_tail(drive, &pc);
2195 tape->door_locked = DOOR_EXPLICITLY_LOCKED;
2198 if (!idetape_create_prevent_cmd(drive, &pc, 0))
2200 retval = idetape_queue_pc_tail(drive, &pc);
2203 tape->door_locked = DOOR_UNLOCKED;
2206 printk(KERN_ERR "ide-tape: MTIO operation %d not supported\n",
2213 * Our character device ioctls. General mtio.h magnetic io commands are
2214 * supported here, and not in the corresponding block interface. Our own
2215 * ide-tape ioctls are supported on both interfaces.
2217 static int idetape_chrdev_ioctl(struct inode *inode, struct file *file,
2218 unsigned int cmd, unsigned long arg)
2220 struct ide_tape_obj *tape = ide_tape_f(file);
2221 ide_drive_t *drive = tape->drive;
2225 int block_offset = 0, position = tape->first_frame;
2226 void __user *argp = (void __user *)arg;
2228 debug_log(DBG_CHRDEV, "Enter %s, cmd=%u\n", __func__, cmd);
2230 if (tape->chrdev_dir == IDETAPE_DIR_WRITE) {
2231 ide_tape_flush_merge_buffer(drive);
2232 idetape_flush_tape_buffers(drive);
2234 if (cmd == MTIOCGET || cmd == MTIOCPOS) {
2235 block_offset = tape->merge_bh_size /
2236 (tape->blk_size * tape->user_bs_factor);
2237 position = idetape_read_position(drive);
2243 if (copy_from_user(&mtop, argp, sizeof(struct mtop)))
2245 return idetape_mtioctop(drive, mtop.mt_op, mtop.mt_count);
2247 memset(&mtget, 0, sizeof(struct mtget));
2248 mtget.mt_type = MT_ISSCSI2;
2249 mtget.mt_blkno = position / tape->user_bs_factor - block_offset;
2251 ((tape->blk_size * tape->user_bs_factor)
2252 << MT_ST_BLKSIZE_SHIFT) & MT_ST_BLKSIZE_MASK;
2254 if (tape->drv_write_prot)
2255 mtget.mt_gstat |= GMT_WR_PROT(0xffffffff);
2257 if (copy_to_user(argp, &mtget, sizeof(struct mtget)))
2261 mtpos.mt_blkno = position / tape->user_bs_factor - block_offset;
2262 if (copy_to_user(argp, &mtpos, sizeof(struct mtpos)))
2266 if (tape->chrdev_dir == IDETAPE_DIR_READ)
2267 ide_tape_discard_merge_buffer(drive, 1);
2268 return idetape_blkdev_ioctl(drive, cmd, arg);
2273 * Do a mode sense page 0 with block descriptor and if it succeeds set the tape
2274 * block size with the reported value.
2276 static void ide_tape_get_bsize_from_bdesc(ide_drive_t *drive)
2278 idetape_tape_t *tape = drive->driver_data;
2279 struct ide_atapi_pc pc;
2281 idetape_create_mode_sense_cmd(&pc, IDETAPE_BLOCK_DESCRIPTOR);
2282 if (idetape_queue_pc_tail(drive, &pc)) {
2283 printk(KERN_ERR "ide-tape: Can't get block descriptor\n");
2284 if (tape->blk_size == 0) {
2285 printk(KERN_WARNING "ide-tape: Cannot deal with zero "
2286 "block size, assuming 32k\n");
2287 tape->blk_size = 32768;
2291 tape->blk_size = (pc.buf[4 + 5] << 16) +
2292 (pc.buf[4 + 6] << 8) +
2294 tape->drv_write_prot = (pc.buf[2] & 0x80) >> 7;
2297 static int idetape_chrdev_open(struct inode *inode, struct file *filp)
2299 unsigned int minor = iminor(inode), i = minor & ~0xc0;
2301 idetape_tape_t *tape;
2302 struct ide_atapi_pc pc;
2305 if (i >= MAX_HWIFS * MAX_DRIVES)
2308 tape = ide_tape_chrdev_get(i);
2312 debug_log(DBG_CHRDEV, "Enter %s\n", __func__);
2315 * We really want to do nonseekable_open(inode, filp); here, but some
2316 * versions of tar incorrectly call lseek on tapes and bail out if that
2317 * fails. So we disallow pread() and pwrite(), but permit lseeks.
2319 filp->f_mode &= ~(FMODE_PREAD | FMODE_PWRITE);
2321 drive = tape->drive;
2323 filp->private_data = tape;
2325 if (test_and_set_bit(IDETAPE_FLAG_BUSY, &tape->flags)) {
2330 retval = idetape_wait_ready(drive, 60 * HZ);
2332 clear_bit(IDETAPE_FLAG_BUSY, &tape->flags);
2333 printk(KERN_ERR "ide-tape: %s: drive not ready\n", tape->name);
2337 idetape_read_position(drive);
2338 if (!test_bit(IDETAPE_FLAG_ADDRESS_VALID, &tape->flags))
2339 (void)idetape_rewind_tape(drive);
2341 /* Read block size and write protect status from drive. */
2342 ide_tape_get_bsize_from_bdesc(drive);
2344 /* Set write protect flag if device is opened as read-only. */
2345 if ((filp->f_flags & O_ACCMODE) == O_RDONLY)
2346 tape->write_prot = 1;
2348 tape->write_prot = tape->drv_write_prot;
2350 /* Make sure drive isn't write protected if user wants to write. */
2351 if (tape->write_prot) {
2352 if ((filp->f_flags & O_ACCMODE) == O_WRONLY ||
2353 (filp->f_flags & O_ACCMODE) == O_RDWR) {
2354 clear_bit(IDETAPE_FLAG_BUSY, &tape->flags);
2360 /* Lock the tape drive door so user can't eject. */
2361 if (tape->chrdev_dir == IDETAPE_DIR_NONE) {
2362 if (idetape_create_prevent_cmd(drive, &pc, 1)) {
2363 if (!idetape_queue_pc_tail(drive, &pc)) {
2364 if (tape->door_locked != DOOR_EXPLICITLY_LOCKED)
2365 tape->door_locked = DOOR_LOCKED;
2376 static void idetape_write_release(ide_drive_t *drive, unsigned int minor)
2378 idetape_tape_t *tape = drive->driver_data;
2380 ide_tape_flush_merge_buffer(drive);
2381 tape->merge_bh = ide_tape_kmalloc_buffer(tape, 1, 0);
2382 if (tape->merge_bh != NULL) {
2383 idetape_pad_zeros(drive, tape->blk_size *
2384 (tape->user_bs_factor - 1));
2385 ide_tape_kfree_buffer(tape);
2386 tape->merge_bh = NULL;
2388 idetape_write_filemark(drive);
2389 idetape_flush_tape_buffers(drive);
2390 idetape_flush_tape_buffers(drive);
2393 static int idetape_chrdev_release(struct inode *inode, struct file *filp)
2395 struct ide_tape_obj *tape = ide_tape_f(filp);
2396 ide_drive_t *drive = tape->drive;
2397 struct ide_atapi_pc pc;
2398 unsigned int minor = iminor(inode);
2401 tape = drive->driver_data;
2403 debug_log(DBG_CHRDEV, "Enter %s\n", __func__);
2405 if (tape->chrdev_dir == IDETAPE_DIR_WRITE)
2406 idetape_write_release(drive, minor);
2407 if (tape->chrdev_dir == IDETAPE_DIR_READ) {
2409 ide_tape_discard_merge_buffer(drive, 1);
2412 if (minor < 128 && test_bit(IDETAPE_FLAG_MEDIUM_PRESENT, &tape->flags))
2413 (void) idetape_rewind_tape(drive);
2414 if (tape->chrdev_dir == IDETAPE_DIR_NONE) {
2415 if (tape->door_locked == DOOR_LOCKED) {
2416 if (idetape_create_prevent_cmd(drive, &pc, 0)) {
2417 if (!idetape_queue_pc_tail(drive, &pc))
2418 tape->door_locked = DOOR_UNLOCKED;
2422 clear_bit(IDETAPE_FLAG_BUSY, &tape->flags);
2429 * check the contents of the ATAPI IDENTIFY command results. We return:
2431 * 1 - If the tape can be supported by us, based on the information we have so
2434 * 0 - If this tape driver is not currently supported by us.
2436 static int idetape_identify_device(ide_drive_t *drive)
2438 u8 gcw[2], protocol, device_type, removable, packet_size;
2440 if (drive->id_read == 0)
2443 *((unsigned short *) &gcw) = drive->id->config;
2445 protocol = (gcw[1] & 0xC0) >> 6;
2446 device_type = gcw[1] & 0x1F;
2447 removable = !!(gcw[0] & 0x80);
2448 packet_size = gcw[0] & 0x3;
2450 /* Check that we can support this device */
2452 printk(KERN_ERR "ide-tape: Protocol (0x%02x) is not ATAPI\n",
2454 else if (device_type != 1)
2455 printk(KERN_ERR "ide-tape: Device type (0x%02x) is not set "
2456 "to tape\n", device_type);
2457 else if (!removable)
2458 printk(KERN_ERR "ide-tape: The removable flag is not set\n");
2459 else if (packet_size != 0) {
2460 printk(KERN_ERR "ide-tape: Packet size (0x%02x) is not 12"
2461 " bytes\n", packet_size);
2467 static void idetape_get_inquiry_results(ide_drive_t *drive)
2469 idetape_tape_t *tape = drive->driver_data;
2470 struct ide_atapi_pc pc;
2471 char fw_rev[6], vendor_id[10], product_id[18];
2473 idetape_create_inquiry_cmd(&pc);
2474 if (idetape_queue_pc_tail(drive, &pc)) {
2475 printk(KERN_ERR "ide-tape: %s: can't get INQUIRY results\n",
2479 memcpy(vendor_id, &pc.buf[8], 8);
2480 memcpy(product_id, &pc.buf[16], 16);
2481 memcpy(fw_rev, &pc.buf[32], 4);
2483 ide_fixstring(vendor_id, 10, 0);
2484 ide_fixstring(product_id, 18, 0);
2485 ide_fixstring(fw_rev, 6, 0);
2487 printk(KERN_INFO "ide-tape: %s <-> %s: %s %s rev %s\n",
2488 drive->name, tape->name, vendor_id, product_id, fw_rev);
2492 * Ask the tape about its various parameters. In particular, we will adjust our
2493 * data transfer buffer size to the recommended value as returned by the tape.
2495 static void idetape_get_mode_sense_results(ide_drive_t *drive)
2497 idetape_tape_t *tape = drive->driver_data;
2498 struct ide_atapi_pc pc;
2500 u8 speed, max_speed;
2502 idetape_create_mode_sense_cmd(&pc, IDETAPE_CAPABILITIES_PAGE);
2503 if (idetape_queue_pc_tail(drive, &pc)) {
2504 printk(KERN_ERR "ide-tape: Can't get tape parameters - assuming"
2505 " some default values\n");
2506 tape->blk_size = 512;
2507 put_unaligned(52, (u16 *)&tape->caps[12]);
2508 put_unaligned(540, (u16 *)&tape->caps[14]);
2509 put_unaligned(6*52, (u16 *)&tape->caps[16]);
2512 caps = pc.buf + 4 + pc.buf[3];
2514 /* convert to host order and save for later use */
2515 speed = be16_to_cpu(*(u16 *)&caps[14]);
2516 max_speed = be16_to_cpu(*(u16 *)&caps[8]);
2518 put_unaligned(max_speed, (u16 *)&caps[8]);
2519 put_unaligned(be16_to_cpu(*(u16 *)&caps[12]), (u16 *)&caps[12]);
2520 put_unaligned(speed, (u16 *)&caps[14]);
2521 put_unaligned(be16_to_cpu(*(u16 *)&caps[16]), (u16 *)&caps[16]);
2524 printk(KERN_INFO "ide-tape: %s: invalid tape speed "
2525 "(assuming 650KB/sec)\n", drive->name);
2526 put_unaligned(650, (u16 *)&caps[14]);
2529 printk(KERN_INFO "ide-tape: %s: invalid max_speed "
2530 "(assuming 650KB/sec)\n", drive->name);
2531 put_unaligned(650, (u16 *)&caps[8]);
2534 memcpy(&tape->caps, caps, 20);
2536 tape->blk_size = 512;
2537 else if (caps[7] & 0x04)
2538 tape->blk_size = 1024;
2541 #ifdef CONFIG_IDE_PROC_FS
2542 static void idetape_add_settings(ide_drive_t *drive)
2544 idetape_tape_t *tape = drive->driver_data;
2546 ide_add_setting(drive, "buffer", SETTING_READ, TYPE_SHORT, 0, 0xffff,
2547 1, 2, (u16 *)&tape->caps[16], NULL);
2548 ide_add_setting(drive, "speed", SETTING_READ, TYPE_SHORT, 0, 0xffff,
2549 1, 1, (u16 *)&tape->caps[14], NULL);
2550 ide_add_setting(drive, "buffer_size", SETTING_READ, TYPE_INT, 0, 0xffff,
2551 1, 1024, &tape->buffer_size, NULL);
2552 ide_add_setting(drive, "tdsc", SETTING_RW, TYPE_INT, IDETAPE_DSC_RW_MIN,
2553 IDETAPE_DSC_RW_MAX, 1000, HZ, &tape->best_dsc_rw_freq,
2555 ide_add_setting(drive, "dsc_overlap", SETTING_RW, TYPE_BYTE, 0, 1, 1,
2556 1, &drive->dsc_overlap, NULL);
2557 ide_add_setting(drive, "avg_speed", SETTING_READ, TYPE_INT, 0, 0xffff,
2558 1, 1, &tape->avg_speed, NULL);
2559 ide_add_setting(drive, "debug_mask", SETTING_RW, TYPE_INT, 0, 0xffff, 1,
2560 1, &tape->debug_mask, NULL);
2563 static inline void idetape_add_settings(ide_drive_t *drive) { ; }
2567 * The function below is called to:
2569 * 1. Initialize our various state variables.
2570 * 2. Ask the tape for its capabilities.
2571 * 3. Allocate a buffer which will be used for data transfer. The buffer size
2572 * is chosen based on the recommendation which we received in step 2.
2574 * Note that at this point ide.c already assigned us an irq, so that we can
2575 * queue requests here and wait for their completion.
2577 static void idetape_setup(ide_drive_t *drive, idetape_tape_t *tape, int minor)
2583 u16 *ctl = (u16 *)&tape->caps[12];
2585 spin_lock_init(&tape->lock);
2586 drive->dsc_overlap = 1;
2587 if (drive->hwif->host_flags & IDE_HFLAG_NO_DSC) {
2588 printk(KERN_INFO "ide-tape: %s: disabling DSC overlap\n",
2590 drive->dsc_overlap = 0;
2592 /* Seagate Travan drives do not support DSC overlap. */
2593 if (strstr(drive->id->model, "Seagate STT3401"))
2594 drive->dsc_overlap = 0;
2595 tape->minor = minor;
2596 tape->name[0] = 'h';
2597 tape->name[1] = 't';
2598 tape->name[2] = '0' + minor;
2599 tape->chrdev_dir = IDETAPE_DIR_NONE;
2600 tape->pc = tape->pc_stack;
2601 *((unsigned short *) &gcw) = drive->id->config;
2603 /* Command packet DRQ type */
2604 if (((gcw[0] & 0x60) >> 5) == 1)
2605 set_bit(IDETAPE_FLAG_DRQ_INTERRUPT, &tape->flags);
2607 idetape_get_inquiry_results(drive);
2608 idetape_get_mode_sense_results(drive);
2609 ide_tape_get_bsize_from_bdesc(drive);
2610 tape->user_bs_factor = 1;
2611 tape->buffer_size = *ctl * tape->blk_size;
2612 while (tape->buffer_size > 0xffff) {
2613 printk(KERN_NOTICE "ide-tape: decreasing stage size\n");
2615 tape->buffer_size = *ctl * tape->blk_size;
2617 buffer_size = tape->buffer_size;
2618 tape->pages_per_buffer = buffer_size / PAGE_SIZE;
2619 if (buffer_size % PAGE_SIZE) {
2620 tape->pages_per_buffer++;
2621 tape->excess_bh_size = PAGE_SIZE - buffer_size % PAGE_SIZE;
2624 /* select the "best" DSC read/write polling freq */
2625 speed = max(*(u16 *)&tape->caps[14], *(u16 *)&tape->caps[8]);
2627 t = (IDETAPE_FIFO_THRESHOLD * tape->buffer_size * HZ) / (speed * 1000);
2630 * Ensure that the number we got makes sense; limit it within
2631 * IDETAPE_DSC_RW_MIN and IDETAPE_DSC_RW_MAX.
2633 tape->best_dsc_rw_freq = clamp_t(unsigned long, t, IDETAPE_DSC_RW_MIN,
2634 IDETAPE_DSC_RW_MAX);
2635 printk(KERN_INFO "ide-tape: %s <-> %s: %dKBps, %d*%dkB buffer, "
2637 drive->name, tape->name, *(u16 *)&tape->caps[14],
2638 (*(u16 *)&tape->caps[16] * 512) / tape->buffer_size,
2639 tape->buffer_size / 1024,
2640 tape->best_dsc_rw_freq * 1000 / HZ,
2641 drive->using_dma ? ", DMA":"");
2643 idetape_add_settings(drive);
2646 static void ide_tape_remove(ide_drive_t *drive)
2648 idetape_tape_t *tape = drive->driver_data;
2650 ide_proc_unregister_driver(drive, tape->driver);
2652 ide_unregister_region(tape->disk);
2657 static void ide_tape_release(struct kref *kref)
2659 struct ide_tape_obj *tape = to_ide_tape(kref);
2660 ide_drive_t *drive = tape->drive;
2661 struct gendisk *g = tape->disk;
2663 BUG_ON(tape->merge_bh_size);
2665 drive->dsc_overlap = 0;
2666 drive->driver_data = NULL;
2667 device_destroy(idetape_sysfs_class, MKDEV(IDETAPE_MAJOR, tape->minor));
2668 device_destroy(idetape_sysfs_class,
2669 MKDEV(IDETAPE_MAJOR, tape->minor + 128));
2670 idetape_devs[tape->minor] = NULL;
2671 g->private_data = NULL;
2676 #ifdef CONFIG_IDE_PROC_FS
2677 static int proc_idetape_read_name
2678 (char *page, char **start, off_t off, int count, int *eof, void *data)
2680 ide_drive_t *drive = (ide_drive_t *) data;
2681 idetape_tape_t *tape = drive->driver_data;
2685 len = sprintf(out, "%s\n", tape->name);
2686 PROC_IDE_READ_RETURN(page, start, off, count, eof, len);
2689 static ide_proc_entry_t idetape_proc[] = {
2690 { "capacity", S_IFREG|S_IRUGO, proc_ide_read_capacity, NULL },
2691 { "name", S_IFREG|S_IRUGO, proc_idetape_read_name, NULL },
2692 { NULL, 0, NULL, NULL }
2696 static int ide_tape_probe(ide_drive_t *);
2698 static ide_driver_t idetape_driver = {
2700 .owner = THIS_MODULE,
2702 .bus = &ide_bus_type,
2704 .probe = ide_tape_probe,
2705 .remove = ide_tape_remove,
2706 .version = IDETAPE_VERSION,
2708 .supports_dsc_overlap = 1,
2709 .do_request = idetape_do_request,
2710 .end_request = idetape_end_request,
2711 .error = __ide_error,
2712 .abort = __ide_abort,
2713 #ifdef CONFIG_IDE_PROC_FS
2714 .proc = idetape_proc,
2718 /* Our character device supporting functions, passed to register_chrdev. */
2719 static const struct file_operations idetape_fops = {
2720 .owner = THIS_MODULE,
2721 .read = idetape_chrdev_read,
2722 .write = idetape_chrdev_write,
2723 .ioctl = idetape_chrdev_ioctl,
2724 .open = idetape_chrdev_open,
2725 .release = idetape_chrdev_release,
2728 static int idetape_open(struct inode *inode, struct file *filp)
2730 struct gendisk *disk = inode->i_bdev->bd_disk;
2731 struct ide_tape_obj *tape;
2733 tape = ide_tape_get(disk);
2740 static int idetape_release(struct inode *inode, struct file *filp)
2742 struct gendisk *disk = inode->i_bdev->bd_disk;
2743 struct ide_tape_obj *tape = ide_tape_g(disk);
2750 static int idetape_ioctl(struct inode *inode, struct file *file,
2751 unsigned int cmd, unsigned long arg)
2753 struct block_device *bdev = inode->i_bdev;
2754 struct ide_tape_obj *tape = ide_tape_g(bdev->bd_disk);
2755 ide_drive_t *drive = tape->drive;
2756 int err = generic_ide_ioctl(drive, file, bdev, cmd, arg);
2758 err = idetape_blkdev_ioctl(drive, cmd, arg);
2762 static struct block_device_operations idetape_block_ops = {
2763 .owner = THIS_MODULE,
2764 .open = idetape_open,
2765 .release = idetape_release,
2766 .ioctl = idetape_ioctl,
2769 static int ide_tape_probe(ide_drive_t *drive)
2771 idetape_tape_t *tape;
2775 if (!strstr("ide-tape", drive->driver_req))
2777 if (!drive->present)
2779 if (drive->media != ide_tape)
2781 if (!idetape_identify_device(drive)) {
2782 printk(KERN_ERR "ide-tape: %s: not supported by this version of"
2783 " the driver\n", drive->name);
2786 tape = kzalloc(sizeof(idetape_tape_t), GFP_KERNEL);
2788 printk(KERN_ERR "ide-tape: %s: Can't allocate a tape struct\n",
2793 g = alloc_disk(1 << PARTN_BITS);
2797 ide_init_disk(g, drive);
2799 ide_proc_register_driver(drive, &idetape_driver);
2801 kref_init(&tape->kref);
2803 tape->drive = drive;
2804 tape->driver = &idetape_driver;
2807 g->private_data = &tape->driver;
2809 drive->driver_data = tape;
2811 mutex_lock(&idetape_ref_mutex);
2812 for (minor = 0; idetape_devs[minor]; minor++)
2814 idetape_devs[minor] = tape;
2815 mutex_unlock(&idetape_ref_mutex);
2817 idetape_setup(drive, tape, minor);
2819 device_create(idetape_sysfs_class, &drive->gendev,
2820 MKDEV(IDETAPE_MAJOR, minor), "%s", tape->name);
2821 device_create(idetape_sysfs_class, &drive->gendev,
2822 MKDEV(IDETAPE_MAJOR, minor + 128), "n%s", tape->name);
2824 g->fops = &idetape_block_ops;
2825 ide_register_region(g);
2835 static void __exit idetape_exit(void)
2837 driver_unregister(&idetape_driver.gen_driver);
2838 class_destroy(idetape_sysfs_class);
2839 unregister_chrdev(IDETAPE_MAJOR, "ht");
2842 static int __init idetape_init(void)
2845 idetape_sysfs_class = class_create(THIS_MODULE, "ide_tape");
2846 if (IS_ERR(idetape_sysfs_class)) {
2847 idetape_sysfs_class = NULL;
2848 printk(KERN_ERR "Unable to create sysfs class for ide tapes\n");
2853 if (register_chrdev(IDETAPE_MAJOR, "ht", &idetape_fops)) {
2854 printk(KERN_ERR "ide-tape: Failed to register chrdev"
2857 goto out_free_class;
2860 error = driver_register(&idetape_driver.gen_driver);
2862 goto out_free_driver;
2867 driver_unregister(&idetape_driver.gen_driver);
2869 class_destroy(idetape_sysfs_class);
2874 MODULE_ALIAS("ide:*m-tape*");
2875 module_init(idetape_init);
2876 module_exit(idetape_exit);
2877 MODULE_ALIAS_CHARDEV_MAJOR(IDETAPE_MAJOR);
2878 MODULE_DESCRIPTION("ATAPI Streaming TAPE Driver");
2879 MODULE_LICENSE("GPL");