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 static void ide_tape_io_buffers(ide_drive_t *drive, struct ide_atapi_pc *pc,
784 unsigned int bcount, int write)
787 idetape_output_buffers(drive, pc, bcount);
789 idetape_input_buffers(drive, pc, bcount);
793 * This is the usual interrupt handler which will be called during a packet
794 * command. We will transfer some of the data (as requested by the drive) and
795 * will re-point interrupt handler to us. When data transfer is finished, we
796 * will act according to the algorithm described before
799 static ide_startstop_t idetape_pc_intr(ide_drive_t *drive)
801 ide_hwif_t *hwif = drive->hwif;
802 idetape_tape_t *tape = drive->driver_data;
803 struct ide_atapi_pc *pc = tape->pc;
804 xfer_func_t *xferfunc;
809 debug_log(DBG_PROCS, "Enter %s - interrupt handler\n", __func__);
811 /* Clear the interrupt */
812 stat = ide_read_status(drive);
814 if (pc->flags & PC_FLAG_DMA_IN_PROGRESS) {
815 if (hwif->dma_ops->dma_end(drive) || (stat & ERR_STAT)) {
816 pc->flags |= PC_FLAG_DMA_ERROR;
818 pc->xferred = pc->req_xfer;
819 idetape_update_buffers(pc);
821 debug_log(DBG_PROCS, "DMA finished\n");
825 /* No more interrupts */
826 if ((stat & DRQ_STAT) == 0) {
827 debug_log(DBG_SENSE, "Packet command completed, %d bytes"
828 " transferred\n", pc->xferred);
830 pc->flags &= ~PC_FLAG_DMA_IN_PROGRESS;
831 local_irq_enable_in_hardirq();
833 if ((stat & ERR_STAT) && pc->c[0] == REQUEST_SENSE)
835 if ((stat & ERR_STAT) || (pc->flags & PC_FLAG_DMA_ERROR)) {
837 debug_log(DBG_ERR, "%s: I/O error\n", tape->name);
839 if (pc->c[0] == REQUEST_SENSE) {
840 printk(KERN_ERR "%s: I/O error in request sense"
841 " command\n", drive->name);
842 return ide_do_reset(drive);
844 debug_log(DBG_ERR, "[cmd %x]: check condition\n",
847 /* Retry operation */
848 idetape_retry_pc(drive);
852 if ((pc->flags & PC_FLAG_WAIT_FOR_DSC) &&
853 (stat & SEEK_STAT) == 0) {
854 ide_tape_handle_dsc(drive);
857 /* Command finished - Call the callback function */
862 if (pc->flags & PC_FLAG_DMA_IN_PROGRESS) {
863 pc->flags &= ~PC_FLAG_DMA_IN_PROGRESS;
864 printk(KERN_ERR "%s: The device wants to issue more interrupts "
865 "in DMA mode\n", drive->name);
867 return ide_do_reset(drive);
869 /* Get the number of bytes to transfer on this interrupt. */
870 bcount = (hwif->INB(hwif->io_ports.lbah_addr) << 8) |
871 hwif->INB(hwif->io_ports.lbam_addr);
873 ireason = hwif->INB(hwif->io_ports.nsect_addr);
876 printk(KERN_ERR "%s: CoD != 0 in %s\n", drive->name, __func__);
877 return ide_do_reset(drive);
879 if (((ireason & IO) == IO) == !!(pc->flags & PC_FLAG_WRITING)) {
880 /* Hopefully, we will never get here */
881 printk(KERN_ERR "%s: We wanted to %s, but the device wants us "
882 "to %s!\n", drive->name,
883 (ireason & IO) ? "Write" : "Read",
884 (ireason & IO) ? "Read" : "Write");
885 return ide_do_reset(drive);
887 if (!(pc->flags & PC_FLAG_WRITING)) {
888 /* Reading - Check that we have enough space */
889 temp = pc->xferred + bcount;
890 if (temp > pc->req_xfer) {
891 if (temp > pc->buf_size) {
892 printk(KERN_ERR "%s: The device wants to send "
893 "us more data than expected - "
896 ide_pad_transfer(drive, 0, bcount);
897 ide_set_handler(drive, &idetape_pc_intr,
898 IDETAPE_WAIT_CMD, NULL);
901 debug_log(DBG_SENSE, "The device wants to send us more "
902 "data than expected - allowing transfer\n");
904 xferfunc = hwif->input_data;
906 xferfunc = hwif->output_data;
910 ide_tape_io_buffers(drive, pc, bcount,
911 !!(pc->flags & PC_FLAG_WRITING));
913 xferfunc(drive, NULL, pc->cur_pos, bcount);
915 /* Update the current position */
916 pc->xferred += bcount;
917 pc->cur_pos += bcount;
919 debug_log(DBG_SENSE, "[cmd %x] transferred %d bytes on that intr.\n",
922 /* And set the interrupt handler again */
923 ide_set_handler(drive, &idetape_pc_intr, IDETAPE_WAIT_CMD, NULL);
928 * Packet Command Interface
930 * The current Packet Command is available in tape->pc, and will not change
931 * until we finish handling it. Each packet command is associated with a
932 * callback function that will be called when the command is finished.
934 * The handling will be done in three stages:
936 * 1. idetape_issue_pc will send the packet command to the drive, and will set
937 * the interrupt handler to idetape_pc_intr.
939 * 2. On each interrupt, idetape_pc_intr will be called. This step will be
940 * repeated until the device signals us that no more interrupts will be issued.
942 * 3. ATAPI Tape media access commands have immediate status with a delayed
943 * process. In case of a successful initiation of a media access packet command,
944 * the DSC bit will be set when the actual execution of the command is finished.
945 * Since the tape drive will not issue an interrupt, we have to poll for this
946 * event. In this case, we define the request as "low priority request" by
947 * setting rq_status to IDETAPE_RQ_POSTPONED, set a timer to poll for DSC and
950 * ide.c will then give higher priority to requests which originate from the
951 * other device, until will change rq_status to RQ_ACTIVE.
953 * 4. When the packet command is finished, it will be checked for errors.
955 * 5. In case an error was found, we queue a request sense packet command in
956 * front of the request queue and retry the operation up to
957 * IDETAPE_MAX_PC_RETRIES times.
959 * 6. In case no error was found, or we decided to give up and not to retry
960 * again, the callback function will be called and then we will handle the next
963 static ide_startstop_t idetape_transfer_pc(ide_drive_t *drive)
965 idetape_tape_t *tape = drive->driver_data;
967 return ide_transfer_pc(drive, tape->pc, idetape_pc_intr,
968 IDETAPE_WAIT_CMD, NULL);
971 static ide_startstop_t idetape_issue_pc(ide_drive_t *drive,
972 struct ide_atapi_pc *pc)
974 idetape_tape_t *tape = drive->driver_data;
976 if (tape->pc->c[0] == REQUEST_SENSE &&
977 pc->c[0] == REQUEST_SENSE) {
978 printk(KERN_ERR "ide-tape: possible ide-tape.c bug - "
979 "Two request sense in serial were issued\n");
982 if (tape->failed_pc == NULL && pc->c[0] != REQUEST_SENSE)
983 tape->failed_pc = pc;
984 /* Set the current packet command */
987 if (pc->retries > IDETAPE_MAX_PC_RETRIES ||
988 (pc->flags & PC_FLAG_ABORT)) {
990 * We will "abort" retrying a packet command in case legitimate
991 * error code was received (crossing a filemark, or end of the
992 * media, for example).
994 if (!(pc->flags & PC_FLAG_ABORT)) {
995 if (!(pc->c[0] == TEST_UNIT_READY &&
996 tape->sense_key == 2 && tape->asc == 4 &&
997 (tape->ascq == 1 || tape->ascq == 8))) {
998 printk(KERN_ERR "ide-tape: %s: I/O error, "
999 "pc = %2x, key = %2x, "
1000 "asc = %2x, ascq = %2x\n",
1001 tape->name, pc->c[0],
1002 tape->sense_key, tape->asc,
1006 pc->error = IDETAPE_ERROR_GENERAL;
1008 tape->failed_pc = NULL;
1009 pc->callback(drive);
1012 debug_log(DBG_SENSE, "Retry #%d, cmd = %02X\n", pc->retries, pc->c[0]);
1016 return ide_issue_pc(drive, pc, idetape_transfer_pc,
1017 IDETAPE_WAIT_CMD, NULL);
1020 /* A mode sense command is used to "sense" tape parameters. */
1021 static void idetape_create_mode_sense_cmd(struct ide_atapi_pc *pc, u8 page_code)
1023 idetape_init_pc(pc);
1024 pc->c[0] = MODE_SENSE;
1025 if (page_code != IDETAPE_BLOCK_DESCRIPTOR)
1026 /* DBD = 1 - Don't return block descriptors */
1028 pc->c[2] = page_code;
1030 * Changed pc->c[3] to 0 (255 will at best return unused info).
1032 * For SCSI this byte is defined as subpage instead of high byte
1033 * of length and some IDE drives seem to interpret it this way
1034 * and return an error when 255 is used.
1037 /* We will just discard data in that case */
1039 if (page_code == IDETAPE_BLOCK_DESCRIPTOR)
1041 else if (page_code == IDETAPE_CAPABILITIES_PAGE)
1047 static ide_startstop_t idetape_media_access_finished(ide_drive_t *drive)
1049 idetape_tape_t *tape = drive->driver_data;
1050 struct ide_atapi_pc *pc = tape->pc;
1053 stat = ide_read_status(drive);
1055 if (stat & SEEK_STAT) {
1056 if (stat & ERR_STAT) {
1057 /* Error detected */
1058 if (pc->c[0] != TEST_UNIT_READY)
1059 printk(KERN_ERR "ide-tape: %s: I/O error, ",
1061 /* Retry operation */
1062 idetape_retry_pc(drive);
1067 pc->error = IDETAPE_ERROR_GENERAL;
1068 tape->failed_pc = NULL;
1070 pc->callback(drive);
1074 static void idetape_create_read_cmd(idetape_tape_t *tape,
1075 struct ide_atapi_pc *pc,
1076 unsigned int length, struct idetape_bh *bh)
1078 idetape_init_pc(pc);
1080 put_unaligned(cpu_to_be32(length), (unsigned int *) &pc->c[1]);
1083 atomic_set(&bh->b_count, 0);
1085 pc->buf_size = length * tape->blk_size;
1086 pc->req_xfer = pc->buf_size;
1087 if (pc->req_xfer == tape->buffer_size)
1088 pc->flags |= PC_FLAG_DMA_OK;
1091 static void idetape_create_write_cmd(idetape_tape_t *tape,
1092 struct ide_atapi_pc *pc,
1093 unsigned int length, struct idetape_bh *bh)
1095 idetape_init_pc(pc);
1097 put_unaligned(cpu_to_be32(length), (unsigned int *) &pc->c[1]);
1099 pc->flags |= PC_FLAG_WRITING;
1101 pc->b_data = bh->b_data;
1102 pc->b_count = atomic_read(&bh->b_count);
1104 pc->buf_size = length * tape->blk_size;
1105 pc->req_xfer = pc->buf_size;
1106 if (pc->req_xfer == tape->buffer_size)
1107 pc->flags |= PC_FLAG_DMA_OK;
1110 static ide_startstop_t idetape_do_request(ide_drive_t *drive,
1111 struct request *rq, sector_t block)
1113 idetape_tape_t *tape = drive->driver_data;
1114 struct ide_atapi_pc *pc = NULL;
1115 struct request *postponed_rq = tape->postponed_rq;
1118 debug_log(DBG_SENSE, "sector: %ld, nr_sectors: %ld,"
1119 " current_nr_sectors: %d\n",
1120 rq->sector, rq->nr_sectors, rq->current_nr_sectors);
1122 if (!blk_special_request(rq)) {
1123 /* We do not support buffer cache originated requests. */
1124 printk(KERN_NOTICE "ide-tape: %s: Unsupported request in "
1125 "request queue (%d)\n", drive->name, rq->cmd_type);
1126 ide_end_request(drive, 0, 0);
1130 /* Retry a failed packet command */
1131 if (tape->failed_pc && tape->pc->c[0] == REQUEST_SENSE) {
1132 pc = tape->failed_pc;
1136 if (postponed_rq != NULL)
1137 if (rq != postponed_rq) {
1138 printk(KERN_ERR "ide-tape: ide-tape.c bug - "
1139 "Two DSC requests were queued\n");
1140 idetape_end_request(drive, 0, 0);
1144 tape->postponed_rq = NULL;
1147 * If the tape is still busy, postpone our request and service
1148 * the other device meanwhile.
1150 stat = ide_read_status(drive);
1152 if (!drive->dsc_overlap && !(rq->cmd[0] & REQ_IDETAPE_PC2))
1153 set_bit(IDETAPE_FLAG_IGNORE_DSC, &tape->flags);
1155 if (drive->post_reset == 1) {
1156 set_bit(IDETAPE_FLAG_IGNORE_DSC, &tape->flags);
1157 drive->post_reset = 0;
1160 if (!test_and_clear_bit(IDETAPE_FLAG_IGNORE_DSC, &tape->flags) &&
1161 (stat & SEEK_STAT) == 0) {
1162 if (postponed_rq == NULL) {
1163 tape->dsc_polling_start = jiffies;
1164 tape->dsc_poll_freq = tape->best_dsc_rw_freq;
1165 tape->dsc_timeout = jiffies + IDETAPE_DSC_RW_TIMEOUT;
1166 } else if (time_after(jiffies, tape->dsc_timeout)) {
1167 printk(KERN_ERR "ide-tape: %s: DSC timeout\n",
1169 if (rq->cmd[0] & REQ_IDETAPE_PC2) {
1170 idetape_media_access_finished(drive);
1173 return ide_do_reset(drive);
1175 } else if (time_after(jiffies,
1176 tape->dsc_polling_start +
1177 IDETAPE_DSC_MA_THRESHOLD))
1178 tape->dsc_poll_freq = IDETAPE_DSC_MA_SLOW;
1179 idetape_postpone_request(drive);
1182 if (rq->cmd[0] & REQ_IDETAPE_READ) {
1183 pc = idetape_next_pc_storage(drive);
1184 idetape_create_read_cmd(tape, pc, rq->current_nr_sectors,
1185 (struct idetape_bh *)rq->special);
1188 if (rq->cmd[0] & REQ_IDETAPE_WRITE) {
1189 pc = idetape_next_pc_storage(drive);
1190 idetape_create_write_cmd(tape, pc, rq->current_nr_sectors,
1191 (struct idetape_bh *)rq->special);
1194 if (rq->cmd[0] & REQ_IDETAPE_PC1) {
1195 pc = (struct ide_atapi_pc *) rq->buffer;
1196 rq->cmd[0] &= ~(REQ_IDETAPE_PC1);
1197 rq->cmd[0] |= REQ_IDETAPE_PC2;
1200 if (rq->cmd[0] & REQ_IDETAPE_PC2) {
1201 idetape_media_access_finished(drive);
1206 if (test_bit(IDETAPE_FLAG_DRQ_INTERRUPT, &tape->flags))
1207 pc->flags |= PC_FLAG_DRQ_INTERRUPT;
1209 return idetape_issue_pc(drive, pc);
1213 * The function below uses __get_free_pages to allocate a data buffer of size
1214 * tape->buffer_size (or a bit more). We attempt to combine sequential pages as
1217 * It returns a pointer to the newly allocated buffer, or NULL in case of
1220 static struct idetape_bh *ide_tape_kmalloc_buffer(idetape_tape_t *tape,
1221 int full, int clear)
1223 struct idetape_bh *prev_bh, *bh, *merge_bh;
1224 int pages = tape->pages_per_buffer;
1225 unsigned int order, b_allocd;
1226 char *b_data = NULL;
1228 merge_bh = kmalloc(sizeof(struct idetape_bh), GFP_KERNEL);
1233 order = fls(pages) - 1;
1234 bh->b_data = (char *) __get_free_pages(GFP_KERNEL, order);
1237 b_allocd = (1 << order) * PAGE_SIZE;
1241 memset(bh->b_data, 0, b_allocd);
1242 bh->b_reqnext = NULL;
1243 bh->b_size = b_allocd;
1244 atomic_set(&bh->b_count, full ? bh->b_size : 0);
1247 order = fls(pages) - 1;
1248 b_data = (char *) __get_free_pages(GFP_KERNEL, order);
1251 b_allocd = (1 << order) * PAGE_SIZE;
1254 memset(b_data, 0, b_allocd);
1256 /* newly allocated page frames below buffer header or ...*/
1257 if (bh->b_data == b_data + b_allocd) {
1258 bh->b_size += b_allocd;
1259 bh->b_data -= b_allocd;
1261 atomic_add(b_allocd, &bh->b_count);
1264 /* they are above the header */
1265 if (b_data == bh->b_data + bh->b_size) {
1266 bh->b_size += b_allocd;
1268 atomic_add(b_allocd, &bh->b_count);
1272 bh = kmalloc(sizeof(struct idetape_bh), GFP_KERNEL);
1274 free_pages((unsigned long) b_data, order);
1277 bh->b_reqnext = NULL;
1278 bh->b_data = b_data;
1279 bh->b_size = b_allocd;
1280 atomic_set(&bh->b_count, full ? bh->b_size : 0);
1281 prev_bh->b_reqnext = bh;
1286 bh->b_size -= tape->excess_bh_size;
1288 atomic_sub(tape->excess_bh_size, &bh->b_count);
1291 ide_tape_kfree_buffer(tape);
1295 static int idetape_copy_stage_from_user(idetape_tape_t *tape,
1296 const char __user *buf, int n)
1298 struct idetape_bh *bh = tape->bh;
1304 printk(KERN_ERR "ide-tape: bh == NULL in %s\n",
1308 count = min((unsigned int)
1309 (bh->b_size - atomic_read(&bh->b_count)),
1311 if (copy_from_user(bh->b_data + atomic_read(&bh->b_count), buf,
1315 atomic_add(count, &bh->b_count);
1317 if (atomic_read(&bh->b_count) == bh->b_size) {
1320 atomic_set(&bh->b_count, 0);
1327 static int idetape_copy_stage_to_user(idetape_tape_t *tape, char __user *buf,
1330 struct idetape_bh *bh = tape->bh;
1336 printk(KERN_ERR "ide-tape: bh == NULL in %s\n",
1340 count = min(tape->b_count, n);
1341 if (copy_to_user(buf, tape->b_data, count))
1344 tape->b_data += count;
1345 tape->b_count -= count;
1347 if (!tape->b_count) {
1351 tape->b_data = bh->b_data;
1352 tape->b_count = atomic_read(&bh->b_count);
1359 static void idetape_init_merge_buffer(idetape_tape_t *tape)
1361 struct idetape_bh *bh = tape->merge_bh;
1362 tape->bh = tape->merge_bh;
1364 if (tape->chrdev_dir == IDETAPE_DIR_WRITE)
1365 atomic_set(&bh->b_count, 0);
1367 tape->b_data = bh->b_data;
1368 tape->b_count = atomic_read(&bh->b_count);
1373 * Write a filemark if write_filemark=1. Flush the device buffers without
1374 * writing a filemark otherwise.
1376 static void idetape_create_write_filemark_cmd(ide_drive_t *drive,
1377 struct ide_atapi_pc *pc, int write_filemark)
1379 idetape_init_pc(pc);
1380 pc->c[0] = WRITE_FILEMARKS;
1381 pc->c[4] = write_filemark;
1382 pc->flags |= PC_FLAG_WAIT_FOR_DSC;
1385 static void idetape_create_test_unit_ready_cmd(struct ide_atapi_pc *pc)
1387 idetape_init_pc(pc);
1388 pc->c[0] = TEST_UNIT_READY;
1392 * We add a special packet command request to the tail of the request queue, and
1393 * wait for it to be serviced. This is not to be called from within the request
1394 * handling part of the driver! We allocate here data on the stack and it is
1395 * valid until the request is finished. This is not the case for the bottom part
1396 * of the driver, where we are always leaving the functions to wait for an
1397 * interrupt or a timer event.
1399 * From the bottom part of the driver, we should allocate safe memory using
1400 * idetape_next_pc_storage() and ide_tape_next_rq_storage(), and add the request
1401 * to the request list without waiting for it to be serviced! In that case, we
1402 * usually use idetape_queue_pc_head().
1404 static int idetape_queue_pc_tail(ide_drive_t *drive, struct ide_atapi_pc *pc)
1406 struct ide_tape_obj *tape = drive->driver_data;
1410 rq = blk_get_request(drive->queue, READ, __GFP_WAIT);
1411 rq->cmd_type = REQ_TYPE_SPECIAL;
1412 rq->cmd[0] = REQ_IDETAPE_PC1;
1413 rq->buffer = (char *)pc;
1414 error = blk_execute_rq(drive->queue, tape->disk, rq, 0);
1415 blk_put_request(rq);
1419 static void idetape_create_load_unload_cmd(ide_drive_t *drive,
1420 struct ide_atapi_pc *pc, int cmd)
1422 idetape_init_pc(pc);
1423 pc->c[0] = START_STOP;
1425 pc->flags |= PC_FLAG_WAIT_FOR_DSC;
1428 static int idetape_wait_ready(ide_drive_t *drive, unsigned long timeout)
1430 idetape_tape_t *tape = drive->driver_data;
1431 struct ide_atapi_pc pc;
1432 int load_attempted = 0;
1434 /* Wait for the tape to become ready */
1435 set_bit(IDETAPE_FLAG_MEDIUM_PRESENT, &tape->flags);
1437 while (time_before(jiffies, timeout)) {
1438 idetape_create_test_unit_ready_cmd(&pc);
1439 if (!idetape_queue_pc_tail(drive, &pc))
1441 if ((tape->sense_key == 2 && tape->asc == 4 && tape->ascq == 2)
1442 || (tape->asc == 0x3A)) {
1446 idetape_create_load_unload_cmd(drive, &pc,
1447 IDETAPE_LU_LOAD_MASK);
1448 idetape_queue_pc_tail(drive, &pc);
1450 /* not about to be ready */
1451 } else if (!(tape->sense_key == 2 && tape->asc == 4 &&
1452 (tape->ascq == 1 || tape->ascq == 8)))
1459 static int idetape_flush_tape_buffers(ide_drive_t *drive)
1461 struct ide_atapi_pc pc;
1464 idetape_create_write_filemark_cmd(drive, &pc, 0);
1465 rc = idetape_queue_pc_tail(drive, &pc);
1468 idetape_wait_ready(drive, 60 * 5 * HZ);
1472 static void idetape_create_read_position_cmd(struct ide_atapi_pc *pc)
1474 idetape_init_pc(pc);
1475 pc->c[0] = READ_POSITION;
1479 static int idetape_read_position(ide_drive_t *drive)
1481 idetape_tape_t *tape = drive->driver_data;
1482 struct ide_atapi_pc pc;
1485 debug_log(DBG_PROCS, "Enter %s\n", __func__);
1487 idetape_create_read_position_cmd(&pc);
1488 if (idetape_queue_pc_tail(drive, &pc))
1490 position = tape->first_frame;
1494 static void idetape_create_locate_cmd(ide_drive_t *drive,
1495 struct ide_atapi_pc *pc,
1496 unsigned int block, u8 partition, int skip)
1498 idetape_init_pc(pc);
1499 pc->c[0] = POSITION_TO_ELEMENT;
1501 put_unaligned(cpu_to_be32(block), (unsigned int *) &pc->c[3]);
1502 pc->c[8] = partition;
1503 pc->flags |= PC_FLAG_WAIT_FOR_DSC;
1506 static int idetape_create_prevent_cmd(ide_drive_t *drive,
1507 struct ide_atapi_pc *pc, int prevent)
1509 idetape_tape_t *tape = drive->driver_data;
1511 /* device supports locking according to capabilities page */
1512 if (!(tape->caps[6] & 0x01))
1515 idetape_init_pc(pc);
1516 pc->c[0] = ALLOW_MEDIUM_REMOVAL;
1521 static void __ide_tape_discard_merge_buffer(ide_drive_t *drive)
1523 idetape_tape_t *tape = drive->driver_data;
1525 if (tape->chrdev_dir != IDETAPE_DIR_READ)
1528 clear_bit(IDETAPE_FLAG_FILEMARK, &tape->flags);
1529 tape->merge_bh_size = 0;
1530 if (tape->merge_bh != NULL) {
1531 ide_tape_kfree_buffer(tape);
1532 tape->merge_bh = NULL;
1535 tape->chrdev_dir = IDETAPE_DIR_NONE;
1539 * Position the tape to the requested block using the LOCATE packet command.
1540 * A READ POSITION command is then issued to check where we are positioned. Like
1541 * all higher level operations, we queue the commands at the tail of the request
1542 * queue and wait for their completion.
1544 static int idetape_position_tape(ide_drive_t *drive, unsigned int block,
1545 u8 partition, int skip)
1547 idetape_tape_t *tape = drive->driver_data;
1549 struct ide_atapi_pc pc;
1551 if (tape->chrdev_dir == IDETAPE_DIR_READ)
1552 __ide_tape_discard_merge_buffer(drive);
1553 idetape_wait_ready(drive, 60 * 5 * HZ);
1554 idetape_create_locate_cmd(drive, &pc, block, partition, skip);
1555 retval = idetape_queue_pc_tail(drive, &pc);
1559 idetape_create_read_position_cmd(&pc);
1560 return (idetape_queue_pc_tail(drive, &pc));
1563 static void ide_tape_discard_merge_buffer(ide_drive_t *drive,
1564 int restore_position)
1566 idetape_tape_t *tape = drive->driver_data;
1569 __ide_tape_discard_merge_buffer(drive);
1570 if (restore_position) {
1571 position = idetape_read_position(drive);
1572 seek = position > 0 ? position : 0;
1573 if (idetape_position_tape(drive, seek, 0, 0)) {
1574 printk(KERN_INFO "ide-tape: %s: position_tape failed in"
1575 " %s\n", tape->name, __func__);
1582 * Generate a read/write request for the block device interface and wait for it
1585 static int idetape_queue_rw_tail(ide_drive_t *drive, int cmd, int blocks,
1586 struct idetape_bh *bh)
1588 idetape_tape_t *tape = drive->driver_data;
1592 debug_log(DBG_SENSE, "%s: cmd=%d\n", __func__, cmd);
1594 rq = blk_get_request(drive->queue, READ, __GFP_WAIT);
1595 rq->cmd_type = REQ_TYPE_SPECIAL;
1597 rq->rq_disk = tape->disk;
1598 rq->special = (void *)bh;
1599 rq->sector = tape->first_frame;
1600 rq->nr_sectors = blocks;
1601 rq->current_nr_sectors = blocks;
1602 blk_execute_rq(drive->queue, tape->disk, rq, 0);
1604 errors = rq->errors;
1605 ret = tape->blk_size * (blocks - rq->current_nr_sectors);
1606 blk_put_request(rq);
1608 if ((cmd & (REQ_IDETAPE_READ | REQ_IDETAPE_WRITE)) == 0)
1612 idetape_init_merge_buffer(tape);
1613 if (errors == IDETAPE_ERROR_GENERAL)
1618 static void idetape_create_inquiry_cmd(struct ide_atapi_pc *pc)
1620 idetape_init_pc(pc);
1626 static void idetape_create_rewind_cmd(ide_drive_t *drive,
1627 struct ide_atapi_pc *pc)
1629 idetape_init_pc(pc);
1630 pc->c[0] = REZERO_UNIT;
1631 pc->flags |= PC_FLAG_WAIT_FOR_DSC;
1634 static void idetape_create_erase_cmd(struct ide_atapi_pc *pc)
1636 idetape_init_pc(pc);
1639 pc->flags |= PC_FLAG_WAIT_FOR_DSC;
1642 static void idetape_create_space_cmd(struct ide_atapi_pc *pc, int count, u8 cmd)
1644 idetape_init_pc(pc);
1646 put_unaligned(cpu_to_be32(count), (unsigned int *) &pc->c[1]);
1648 pc->flags |= PC_FLAG_WAIT_FOR_DSC;
1651 /* Queue up a character device originated write request. */
1652 static int idetape_add_chrdev_write_request(ide_drive_t *drive, int blocks)
1654 idetape_tape_t *tape = drive->driver_data;
1656 debug_log(DBG_CHRDEV, "Enter %s\n", __func__);
1658 return idetape_queue_rw_tail(drive, REQ_IDETAPE_WRITE,
1659 blocks, tape->merge_bh);
1662 static void ide_tape_flush_merge_buffer(ide_drive_t *drive)
1664 idetape_tape_t *tape = drive->driver_data;
1666 struct idetape_bh *bh;
1668 if (tape->chrdev_dir != IDETAPE_DIR_WRITE) {
1669 printk(KERN_ERR "ide-tape: bug: Trying to empty merge buffer"
1670 " but we are not writing.\n");
1673 if (tape->merge_bh_size > tape->buffer_size) {
1674 printk(KERN_ERR "ide-tape: bug: merge_buffer too big\n");
1675 tape->merge_bh_size = tape->buffer_size;
1677 if (tape->merge_bh_size) {
1678 blocks = tape->merge_bh_size / tape->blk_size;
1679 if (tape->merge_bh_size % tape->blk_size) {
1683 i = tape->blk_size - tape->merge_bh_size %
1685 bh = tape->bh->b_reqnext;
1687 atomic_set(&bh->b_count, 0);
1693 printk(KERN_INFO "ide-tape: bug,"
1697 min = min(i, (unsigned int)(bh->b_size -
1698 atomic_read(&bh->b_count)));
1699 memset(bh->b_data + atomic_read(&bh->b_count),
1701 atomic_add(min, &bh->b_count);
1706 (void) idetape_add_chrdev_write_request(drive, blocks);
1707 tape->merge_bh_size = 0;
1709 if (tape->merge_bh != NULL) {
1710 ide_tape_kfree_buffer(tape);
1711 tape->merge_bh = NULL;
1713 tape->chrdev_dir = IDETAPE_DIR_NONE;
1716 static int idetape_init_read(ide_drive_t *drive)
1718 idetape_tape_t *tape = drive->driver_data;
1721 /* Initialize read operation */
1722 if (tape->chrdev_dir != IDETAPE_DIR_READ) {
1723 if (tape->chrdev_dir == IDETAPE_DIR_WRITE) {
1724 ide_tape_flush_merge_buffer(drive);
1725 idetape_flush_tape_buffers(drive);
1727 if (tape->merge_bh || tape->merge_bh_size) {
1728 printk(KERN_ERR "ide-tape: merge_bh_size should be"
1730 tape->merge_bh_size = 0;
1732 tape->merge_bh = ide_tape_kmalloc_buffer(tape, 0, 0);
1733 if (!tape->merge_bh)
1735 tape->chrdev_dir = IDETAPE_DIR_READ;
1738 * Issue a read 0 command to ensure that DSC handshake is
1739 * switched from completion mode to buffer available mode.
1740 * No point in issuing this if DSC overlap isn't supported, some
1741 * drives (Seagate STT3401A) will return an error.
1743 if (drive->dsc_overlap) {
1744 bytes_read = idetape_queue_rw_tail(drive,
1745 REQ_IDETAPE_READ, 0,
1747 if (bytes_read < 0) {
1748 ide_tape_kfree_buffer(tape);
1749 tape->merge_bh = NULL;
1750 tape->chrdev_dir = IDETAPE_DIR_NONE;
1759 /* called from idetape_chrdev_read() to service a chrdev read request. */
1760 static int idetape_add_chrdev_read_request(ide_drive_t *drive, int blocks)
1762 idetape_tape_t *tape = drive->driver_data;
1764 debug_log(DBG_PROCS, "Enter %s, %d blocks\n", __func__, blocks);
1766 /* If we are at a filemark, return a read length of 0 */
1767 if (test_bit(IDETAPE_FLAG_FILEMARK, &tape->flags))
1770 idetape_init_read(drive);
1772 return idetape_queue_rw_tail(drive, REQ_IDETAPE_READ, blocks,
1776 static void idetape_pad_zeros(ide_drive_t *drive, int bcount)
1778 idetape_tape_t *tape = drive->driver_data;
1779 struct idetape_bh *bh;
1785 bh = tape->merge_bh;
1786 count = min(tape->buffer_size, bcount);
1788 blocks = count / tape->blk_size;
1790 atomic_set(&bh->b_count,
1791 min(count, (unsigned int)bh->b_size));
1792 memset(bh->b_data, 0, atomic_read(&bh->b_count));
1793 count -= atomic_read(&bh->b_count);
1796 idetape_queue_rw_tail(drive, REQ_IDETAPE_WRITE, blocks,
1802 * Rewinds the tape to the Beginning Of the current Partition (BOP). We
1803 * currently support only one partition.
1805 static int idetape_rewind_tape(ide_drive_t *drive)
1808 struct ide_atapi_pc pc;
1809 idetape_tape_t *tape;
1810 tape = drive->driver_data;
1812 debug_log(DBG_SENSE, "Enter %s\n", __func__);
1814 idetape_create_rewind_cmd(drive, &pc);
1815 retval = idetape_queue_pc_tail(drive, &pc);
1819 idetape_create_read_position_cmd(&pc);
1820 retval = idetape_queue_pc_tail(drive, &pc);
1826 /* mtio.h compatible commands should be issued to the chrdev interface. */
1827 static int idetape_blkdev_ioctl(ide_drive_t *drive, unsigned int cmd,
1830 idetape_tape_t *tape = drive->driver_data;
1831 void __user *argp = (void __user *)arg;
1833 struct idetape_config {
1834 int dsc_rw_frequency;
1835 int dsc_media_access_frequency;
1839 debug_log(DBG_PROCS, "Enter %s\n", __func__);
1843 if (copy_from_user(&config, argp, sizeof(config)))
1845 tape->best_dsc_rw_freq = config.dsc_rw_frequency;
1848 config.dsc_rw_frequency = (int) tape->best_dsc_rw_freq;
1849 config.nr_stages = 1;
1850 if (copy_to_user(argp, &config, sizeof(config)))
1859 static int idetape_space_over_filemarks(ide_drive_t *drive, short mt_op,
1862 idetape_tape_t *tape = drive->driver_data;
1863 struct ide_atapi_pc pc;
1864 int retval, count = 0;
1865 int sprev = !!(tape->caps[4] & 0x20);
1869 if (MTBSF == mt_op || MTBSFM == mt_op) {
1872 mt_count = -mt_count;
1875 if (tape->chrdev_dir == IDETAPE_DIR_READ) {
1876 tape->merge_bh_size = 0;
1877 if (test_and_clear_bit(IDETAPE_FLAG_FILEMARK, &tape->flags))
1879 ide_tape_discard_merge_buffer(drive, 0);
1885 idetape_create_space_cmd(&pc, mt_count - count,
1886 IDETAPE_SPACE_OVER_FILEMARK);
1887 return idetape_queue_pc_tail(drive, &pc);
1892 retval = idetape_space_over_filemarks(drive, MTFSF,
1896 count = (MTBSFM == mt_op ? 1 : -1);
1897 return idetape_space_over_filemarks(drive, MTFSF, count);
1899 printk(KERN_ERR "ide-tape: MTIO operation %d not supported\n",
1906 * Our character device read / write functions.
1908 * The tape is optimized to maximize throughput when it is transferring an
1909 * integral number of the "continuous transfer limit", which is a parameter of
1910 * the specific tape (26kB on my particular tape, 32kB for Onstream).
1912 * As of version 1.3 of the driver, the character device provides an abstract
1913 * continuous view of the media - any mix of block sizes (even 1 byte) on the
1914 * same backup/restore procedure is supported. The driver will internally
1915 * convert the requests to the recommended transfer unit, so that an unmatch
1916 * between the user's block size to the recommended size will only result in a
1917 * (slightly) increased driver overhead, but will no longer hit performance.
1918 * This is not applicable to Onstream.
1920 static ssize_t idetape_chrdev_read(struct file *file, char __user *buf,
1921 size_t count, loff_t *ppos)
1923 struct ide_tape_obj *tape = ide_tape_f(file);
1924 ide_drive_t *drive = tape->drive;
1925 ssize_t bytes_read, temp, actually_read = 0, rc;
1927 u16 ctl = *(u16 *)&tape->caps[12];
1929 debug_log(DBG_CHRDEV, "Enter %s, count %Zd\n", __func__, count);
1931 if (tape->chrdev_dir != IDETAPE_DIR_READ) {
1932 if (test_bit(IDETAPE_FLAG_DETECT_BS, &tape->flags))
1933 if (count > tape->blk_size &&
1934 (count % tape->blk_size) == 0)
1935 tape->user_bs_factor = count / tape->blk_size;
1937 rc = idetape_init_read(drive);
1942 if (tape->merge_bh_size) {
1943 actually_read = min((unsigned int)(tape->merge_bh_size),
1944 (unsigned int)count);
1945 if (idetape_copy_stage_to_user(tape, buf, actually_read))
1947 buf += actually_read;
1948 tape->merge_bh_size -= actually_read;
1949 count -= actually_read;
1951 while (count >= tape->buffer_size) {
1952 bytes_read = idetape_add_chrdev_read_request(drive, ctl);
1953 if (bytes_read <= 0)
1955 if (idetape_copy_stage_to_user(tape, buf, bytes_read))
1958 count -= bytes_read;
1959 actually_read += bytes_read;
1962 bytes_read = idetape_add_chrdev_read_request(drive, ctl);
1963 if (bytes_read <= 0)
1965 temp = min((unsigned long)count, (unsigned long)bytes_read);
1966 if (idetape_copy_stage_to_user(tape, buf, temp))
1968 actually_read += temp;
1969 tape->merge_bh_size = bytes_read-temp;
1972 if (!actually_read && test_bit(IDETAPE_FLAG_FILEMARK, &tape->flags)) {
1973 debug_log(DBG_SENSE, "%s: spacing over filemark\n", tape->name);
1975 idetape_space_over_filemarks(drive, MTFSF, 1);
1979 return ret ? ret : actually_read;
1982 static ssize_t idetape_chrdev_write(struct file *file, const char __user *buf,
1983 size_t count, loff_t *ppos)
1985 struct ide_tape_obj *tape = ide_tape_f(file);
1986 ide_drive_t *drive = tape->drive;
1987 ssize_t actually_written = 0;
1989 u16 ctl = *(u16 *)&tape->caps[12];
1991 /* The drive is write protected. */
1992 if (tape->write_prot)
1995 debug_log(DBG_CHRDEV, "Enter %s, count %Zd\n", __func__, count);
1997 /* Initialize write operation */
1998 if (tape->chrdev_dir != IDETAPE_DIR_WRITE) {
1999 if (tape->chrdev_dir == IDETAPE_DIR_READ)
2000 ide_tape_discard_merge_buffer(drive, 1);
2001 if (tape->merge_bh || tape->merge_bh_size) {
2002 printk(KERN_ERR "ide-tape: merge_bh_size "
2003 "should be 0 now\n");
2004 tape->merge_bh_size = 0;
2006 tape->merge_bh = ide_tape_kmalloc_buffer(tape, 0, 0);
2007 if (!tape->merge_bh)
2009 tape->chrdev_dir = IDETAPE_DIR_WRITE;
2010 idetape_init_merge_buffer(tape);
2013 * Issue a write 0 command to ensure that DSC handshake is
2014 * switched from completion mode to buffer available mode. No
2015 * point in issuing this if DSC overlap isn't supported, some
2016 * drives (Seagate STT3401A) will return an error.
2018 if (drive->dsc_overlap) {
2019 ssize_t retval = idetape_queue_rw_tail(drive,
2020 REQ_IDETAPE_WRITE, 0,
2023 ide_tape_kfree_buffer(tape);
2024 tape->merge_bh = NULL;
2025 tape->chrdev_dir = IDETAPE_DIR_NONE;
2032 if (tape->merge_bh_size) {
2033 if (tape->merge_bh_size >= tape->buffer_size) {
2034 printk(KERN_ERR "ide-tape: bug: merge buf too big\n");
2035 tape->merge_bh_size = 0;
2037 actually_written = min((unsigned int)
2038 (tape->buffer_size - tape->merge_bh_size),
2039 (unsigned int)count);
2040 if (idetape_copy_stage_from_user(tape, buf, actually_written))
2042 buf += actually_written;
2043 tape->merge_bh_size += actually_written;
2044 count -= actually_written;
2046 if (tape->merge_bh_size == tape->buffer_size) {
2048 tape->merge_bh_size = 0;
2049 retval = idetape_add_chrdev_write_request(drive, ctl);
2054 while (count >= tape->buffer_size) {
2056 if (idetape_copy_stage_from_user(tape, buf, tape->buffer_size))
2058 buf += tape->buffer_size;
2059 count -= tape->buffer_size;
2060 retval = idetape_add_chrdev_write_request(drive, ctl);
2061 actually_written += tape->buffer_size;
2066 actually_written += count;
2067 if (idetape_copy_stage_from_user(tape, buf, count))
2069 tape->merge_bh_size += count;
2071 return ret ? ret : actually_written;
2074 static int idetape_write_filemark(ide_drive_t *drive)
2076 struct ide_atapi_pc pc;
2078 /* Write a filemark */
2079 idetape_create_write_filemark_cmd(drive, &pc, 1);
2080 if (idetape_queue_pc_tail(drive, &pc)) {
2081 printk(KERN_ERR "ide-tape: Couldn't write a filemark\n");
2088 * Called from idetape_chrdev_ioctl when the general mtio MTIOCTOP ioctl is
2091 * Note: MTBSF and MTBSFM are not supported when the tape doesn't support
2092 * spacing over filemarks in the reverse direction. In this case, MTFSFM is also
2093 * usually not supported.
2095 * The following commands are currently not supported:
2097 * MTFSS, MTBSS, MTWSM, MTSETDENSITY, MTSETDRVBUFFER, MT_ST_BOOLEANS,
2098 * MT_ST_WRITE_THRESHOLD.
2100 static int idetape_mtioctop(ide_drive_t *drive, short mt_op, int mt_count)
2102 idetape_tape_t *tape = drive->driver_data;
2103 struct ide_atapi_pc pc;
2106 debug_log(DBG_ERR, "Handling MTIOCTOP ioctl: mt_op=%d, mt_count=%d\n",
2116 return idetape_space_over_filemarks(drive, mt_op, mt_count);
2123 if (tape->write_prot)
2125 ide_tape_discard_merge_buffer(drive, 1);
2126 for (i = 0; i < mt_count; i++) {
2127 retval = idetape_write_filemark(drive);
2133 ide_tape_discard_merge_buffer(drive, 0);
2134 if (idetape_rewind_tape(drive))
2138 ide_tape_discard_merge_buffer(drive, 0);
2139 idetape_create_load_unload_cmd(drive, &pc,
2140 IDETAPE_LU_LOAD_MASK);
2141 return idetape_queue_pc_tail(drive, &pc);
2145 * If door is locked, attempt to unlock before
2146 * attempting to eject.
2148 if (tape->door_locked) {
2149 if (idetape_create_prevent_cmd(drive, &pc, 0))
2150 if (!idetape_queue_pc_tail(drive, &pc))
2151 tape->door_locked = DOOR_UNLOCKED;
2153 ide_tape_discard_merge_buffer(drive, 0);
2154 idetape_create_load_unload_cmd(drive, &pc,
2155 !IDETAPE_LU_LOAD_MASK);
2156 retval = idetape_queue_pc_tail(drive, &pc);
2158 clear_bit(IDETAPE_FLAG_MEDIUM_PRESENT, &tape->flags);
2161 ide_tape_discard_merge_buffer(drive, 0);
2162 return idetape_flush_tape_buffers(drive);
2164 ide_tape_discard_merge_buffer(drive, 0);
2165 idetape_create_load_unload_cmd(drive, &pc,
2166 IDETAPE_LU_RETENSION_MASK | IDETAPE_LU_LOAD_MASK);
2167 return idetape_queue_pc_tail(drive, &pc);
2169 idetape_create_space_cmd(&pc, 0, IDETAPE_SPACE_TO_EOD);
2170 return idetape_queue_pc_tail(drive, &pc);
2172 (void)idetape_rewind_tape(drive);
2173 idetape_create_erase_cmd(&pc);
2174 return idetape_queue_pc_tail(drive, &pc);
2177 if (mt_count < tape->blk_size ||
2178 mt_count % tape->blk_size)
2180 tape->user_bs_factor = mt_count / tape->blk_size;
2181 clear_bit(IDETAPE_FLAG_DETECT_BS, &tape->flags);
2183 set_bit(IDETAPE_FLAG_DETECT_BS, &tape->flags);
2186 ide_tape_discard_merge_buffer(drive, 0);
2187 return idetape_position_tape(drive,
2188 mt_count * tape->user_bs_factor, tape->partition, 0);
2190 ide_tape_discard_merge_buffer(drive, 0);
2191 return idetape_position_tape(drive, 0, mt_count, 0);
2195 if (!idetape_create_prevent_cmd(drive, &pc, 1))
2197 retval = idetape_queue_pc_tail(drive, &pc);
2200 tape->door_locked = DOOR_EXPLICITLY_LOCKED;
2203 if (!idetape_create_prevent_cmd(drive, &pc, 0))
2205 retval = idetape_queue_pc_tail(drive, &pc);
2208 tape->door_locked = DOOR_UNLOCKED;
2211 printk(KERN_ERR "ide-tape: MTIO operation %d not supported\n",
2218 * Our character device ioctls. General mtio.h magnetic io commands are
2219 * supported here, and not in the corresponding block interface. Our own
2220 * ide-tape ioctls are supported on both interfaces.
2222 static int idetape_chrdev_ioctl(struct inode *inode, struct file *file,
2223 unsigned int cmd, unsigned long arg)
2225 struct ide_tape_obj *tape = ide_tape_f(file);
2226 ide_drive_t *drive = tape->drive;
2230 int block_offset = 0, position = tape->first_frame;
2231 void __user *argp = (void __user *)arg;
2233 debug_log(DBG_CHRDEV, "Enter %s, cmd=%u\n", __func__, cmd);
2235 if (tape->chrdev_dir == IDETAPE_DIR_WRITE) {
2236 ide_tape_flush_merge_buffer(drive);
2237 idetape_flush_tape_buffers(drive);
2239 if (cmd == MTIOCGET || cmd == MTIOCPOS) {
2240 block_offset = tape->merge_bh_size /
2241 (tape->blk_size * tape->user_bs_factor);
2242 position = idetape_read_position(drive);
2248 if (copy_from_user(&mtop, argp, sizeof(struct mtop)))
2250 return idetape_mtioctop(drive, mtop.mt_op, mtop.mt_count);
2252 memset(&mtget, 0, sizeof(struct mtget));
2253 mtget.mt_type = MT_ISSCSI2;
2254 mtget.mt_blkno = position / tape->user_bs_factor - block_offset;
2256 ((tape->blk_size * tape->user_bs_factor)
2257 << MT_ST_BLKSIZE_SHIFT) & MT_ST_BLKSIZE_MASK;
2259 if (tape->drv_write_prot)
2260 mtget.mt_gstat |= GMT_WR_PROT(0xffffffff);
2262 if (copy_to_user(argp, &mtget, sizeof(struct mtget)))
2266 mtpos.mt_blkno = position / tape->user_bs_factor - block_offset;
2267 if (copy_to_user(argp, &mtpos, sizeof(struct mtpos)))
2271 if (tape->chrdev_dir == IDETAPE_DIR_READ)
2272 ide_tape_discard_merge_buffer(drive, 1);
2273 return idetape_blkdev_ioctl(drive, cmd, arg);
2278 * Do a mode sense page 0 with block descriptor and if it succeeds set the tape
2279 * block size with the reported value.
2281 static void ide_tape_get_bsize_from_bdesc(ide_drive_t *drive)
2283 idetape_tape_t *tape = drive->driver_data;
2284 struct ide_atapi_pc pc;
2286 idetape_create_mode_sense_cmd(&pc, IDETAPE_BLOCK_DESCRIPTOR);
2287 if (idetape_queue_pc_tail(drive, &pc)) {
2288 printk(KERN_ERR "ide-tape: Can't get block descriptor\n");
2289 if (tape->blk_size == 0) {
2290 printk(KERN_WARNING "ide-tape: Cannot deal with zero "
2291 "block size, assuming 32k\n");
2292 tape->blk_size = 32768;
2296 tape->blk_size = (pc.buf[4 + 5] << 16) +
2297 (pc.buf[4 + 6] << 8) +
2299 tape->drv_write_prot = (pc.buf[2] & 0x80) >> 7;
2302 static int idetape_chrdev_open(struct inode *inode, struct file *filp)
2304 unsigned int minor = iminor(inode), i = minor & ~0xc0;
2306 idetape_tape_t *tape;
2307 struct ide_atapi_pc pc;
2310 if (i >= MAX_HWIFS * MAX_DRIVES)
2313 tape = ide_tape_chrdev_get(i);
2317 debug_log(DBG_CHRDEV, "Enter %s\n", __func__);
2320 * We really want to do nonseekable_open(inode, filp); here, but some
2321 * versions of tar incorrectly call lseek on tapes and bail out if that
2322 * fails. So we disallow pread() and pwrite(), but permit lseeks.
2324 filp->f_mode &= ~(FMODE_PREAD | FMODE_PWRITE);
2326 drive = tape->drive;
2328 filp->private_data = tape;
2330 if (test_and_set_bit(IDETAPE_FLAG_BUSY, &tape->flags)) {
2335 retval = idetape_wait_ready(drive, 60 * HZ);
2337 clear_bit(IDETAPE_FLAG_BUSY, &tape->flags);
2338 printk(KERN_ERR "ide-tape: %s: drive not ready\n", tape->name);
2342 idetape_read_position(drive);
2343 if (!test_bit(IDETAPE_FLAG_ADDRESS_VALID, &tape->flags))
2344 (void)idetape_rewind_tape(drive);
2346 /* Read block size and write protect status from drive. */
2347 ide_tape_get_bsize_from_bdesc(drive);
2349 /* Set write protect flag if device is opened as read-only. */
2350 if ((filp->f_flags & O_ACCMODE) == O_RDONLY)
2351 tape->write_prot = 1;
2353 tape->write_prot = tape->drv_write_prot;
2355 /* Make sure drive isn't write protected if user wants to write. */
2356 if (tape->write_prot) {
2357 if ((filp->f_flags & O_ACCMODE) == O_WRONLY ||
2358 (filp->f_flags & O_ACCMODE) == O_RDWR) {
2359 clear_bit(IDETAPE_FLAG_BUSY, &tape->flags);
2365 /* Lock the tape drive door so user can't eject. */
2366 if (tape->chrdev_dir == IDETAPE_DIR_NONE) {
2367 if (idetape_create_prevent_cmd(drive, &pc, 1)) {
2368 if (!idetape_queue_pc_tail(drive, &pc)) {
2369 if (tape->door_locked != DOOR_EXPLICITLY_LOCKED)
2370 tape->door_locked = DOOR_LOCKED;
2381 static void idetape_write_release(ide_drive_t *drive, unsigned int minor)
2383 idetape_tape_t *tape = drive->driver_data;
2385 ide_tape_flush_merge_buffer(drive);
2386 tape->merge_bh = ide_tape_kmalloc_buffer(tape, 1, 0);
2387 if (tape->merge_bh != NULL) {
2388 idetape_pad_zeros(drive, tape->blk_size *
2389 (tape->user_bs_factor - 1));
2390 ide_tape_kfree_buffer(tape);
2391 tape->merge_bh = NULL;
2393 idetape_write_filemark(drive);
2394 idetape_flush_tape_buffers(drive);
2395 idetape_flush_tape_buffers(drive);
2398 static int idetape_chrdev_release(struct inode *inode, struct file *filp)
2400 struct ide_tape_obj *tape = ide_tape_f(filp);
2401 ide_drive_t *drive = tape->drive;
2402 struct ide_atapi_pc pc;
2403 unsigned int minor = iminor(inode);
2406 tape = drive->driver_data;
2408 debug_log(DBG_CHRDEV, "Enter %s\n", __func__);
2410 if (tape->chrdev_dir == IDETAPE_DIR_WRITE)
2411 idetape_write_release(drive, minor);
2412 if (tape->chrdev_dir == IDETAPE_DIR_READ) {
2414 ide_tape_discard_merge_buffer(drive, 1);
2417 if (minor < 128 && test_bit(IDETAPE_FLAG_MEDIUM_PRESENT, &tape->flags))
2418 (void) idetape_rewind_tape(drive);
2419 if (tape->chrdev_dir == IDETAPE_DIR_NONE) {
2420 if (tape->door_locked == DOOR_LOCKED) {
2421 if (idetape_create_prevent_cmd(drive, &pc, 0)) {
2422 if (!idetape_queue_pc_tail(drive, &pc))
2423 tape->door_locked = DOOR_UNLOCKED;
2427 clear_bit(IDETAPE_FLAG_BUSY, &tape->flags);
2434 * check the contents of the ATAPI IDENTIFY command results. We return:
2436 * 1 - If the tape can be supported by us, based on the information we have so
2439 * 0 - If this tape driver is not currently supported by us.
2441 static int idetape_identify_device(ide_drive_t *drive)
2443 u8 gcw[2], protocol, device_type, removable, packet_size;
2445 if (drive->id_read == 0)
2448 *((unsigned short *) &gcw) = drive->id->config;
2450 protocol = (gcw[1] & 0xC0) >> 6;
2451 device_type = gcw[1] & 0x1F;
2452 removable = !!(gcw[0] & 0x80);
2453 packet_size = gcw[0] & 0x3;
2455 /* Check that we can support this device */
2457 printk(KERN_ERR "ide-tape: Protocol (0x%02x) is not ATAPI\n",
2459 else if (device_type != 1)
2460 printk(KERN_ERR "ide-tape: Device type (0x%02x) is not set "
2461 "to tape\n", device_type);
2462 else if (!removable)
2463 printk(KERN_ERR "ide-tape: The removable flag is not set\n");
2464 else if (packet_size != 0) {
2465 printk(KERN_ERR "ide-tape: Packet size (0x%02x) is not 12"
2466 " bytes\n", packet_size);
2472 static void idetape_get_inquiry_results(ide_drive_t *drive)
2474 idetape_tape_t *tape = drive->driver_data;
2475 struct ide_atapi_pc pc;
2476 char fw_rev[6], vendor_id[10], product_id[18];
2478 idetape_create_inquiry_cmd(&pc);
2479 if (idetape_queue_pc_tail(drive, &pc)) {
2480 printk(KERN_ERR "ide-tape: %s: can't get INQUIRY results\n",
2484 memcpy(vendor_id, &pc.buf[8], 8);
2485 memcpy(product_id, &pc.buf[16], 16);
2486 memcpy(fw_rev, &pc.buf[32], 4);
2488 ide_fixstring(vendor_id, 10, 0);
2489 ide_fixstring(product_id, 18, 0);
2490 ide_fixstring(fw_rev, 6, 0);
2492 printk(KERN_INFO "ide-tape: %s <-> %s: %s %s rev %s\n",
2493 drive->name, tape->name, vendor_id, product_id, fw_rev);
2497 * Ask the tape about its various parameters. In particular, we will adjust our
2498 * data transfer buffer size to the recommended value as returned by the tape.
2500 static void idetape_get_mode_sense_results(ide_drive_t *drive)
2502 idetape_tape_t *tape = drive->driver_data;
2503 struct ide_atapi_pc pc;
2505 u8 speed, max_speed;
2507 idetape_create_mode_sense_cmd(&pc, IDETAPE_CAPABILITIES_PAGE);
2508 if (idetape_queue_pc_tail(drive, &pc)) {
2509 printk(KERN_ERR "ide-tape: Can't get tape parameters - assuming"
2510 " some default values\n");
2511 tape->blk_size = 512;
2512 put_unaligned(52, (u16 *)&tape->caps[12]);
2513 put_unaligned(540, (u16 *)&tape->caps[14]);
2514 put_unaligned(6*52, (u16 *)&tape->caps[16]);
2517 caps = pc.buf + 4 + pc.buf[3];
2519 /* convert to host order and save for later use */
2520 speed = be16_to_cpu(*(u16 *)&caps[14]);
2521 max_speed = be16_to_cpu(*(u16 *)&caps[8]);
2523 put_unaligned(max_speed, (u16 *)&caps[8]);
2524 put_unaligned(be16_to_cpu(*(u16 *)&caps[12]), (u16 *)&caps[12]);
2525 put_unaligned(speed, (u16 *)&caps[14]);
2526 put_unaligned(be16_to_cpu(*(u16 *)&caps[16]), (u16 *)&caps[16]);
2529 printk(KERN_INFO "ide-tape: %s: invalid tape speed "
2530 "(assuming 650KB/sec)\n", drive->name);
2531 put_unaligned(650, (u16 *)&caps[14]);
2534 printk(KERN_INFO "ide-tape: %s: invalid max_speed "
2535 "(assuming 650KB/sec)\n", drive->name);
2536 put_unaligned(650, (u16 *)&caps[8]);
2539 memcpy(&tape->caps, caps, 20);
2541 tape->blk_size = 512;
2542 else if (caps[7] & 0x04)
2543 tape->blk_size = 1024;
2546 #ifdef CONFIG_IDE_PROC_FS
2547 static void idetape_add_settings(ide_drive_t *drive)
2549 idetape_tape_t *tape = drive->driver_data;
2551 ide_add_setting(drive, "buffer", SETTING_READ, TYPE_SHORT, 0, 0xffff,
2552 1, 2, (u16 *)&tape->caps[16], NULL);
2553 ide_add_setting(drive, "speed", SETTING_READ, TYPE_SHORT, 0, 0xffff,
2554 1, 1, (u16 *)&tape->caps[14], NULL);
2555 ide_add_setting(drive, "buffer_size", SETTING_READ, TYPE_INT, 0, 0xffff,
2556 1, 1024, &tape->buffer_size, NULL);
2557 ide_add_setting(drive, "tdsc", SETTING_RW, TYPE_INT, IDETAPE_DSC_RW_MIN,
2558 IDETAPE_DSC_RW_MAX, 1000, HZ, &tape->best_dsc_rw_freq,
2560 ide_add_setting(drive, "dsc_overlap", SETTING_RW, TYPE_BYTE, 0, 1, 1,
2561 1, &drive->dsc_overlap, NULL);
2562 ide_add_setting(drive, "avg_speed", SETTING_READ, TYPE_INT, 0, 0xffff,
2563 1, 1, &tape->avg_speed, NULL);
2564 ide_add_setting(drive, "debug_mask", SETTING_RW, TYPE_INT, 0, 0xffff, 1,
2565 1, &tape->debug_mask, NULL);
2568 static inline void idetape_add_settings(ide_drive_t *drive) { ; }
2572 * The function below is called to:
2574 * 1. Initialize our various state variables.
2575 * 2. Ask the tape for its capabilities.
2576 * 3. Allocate a buffer which will be used for data transfer. The buffer size
2577 * is chosen based on the recommendation which we received in step 2.
2579 * Note that at this point ide.c already assigned us an irq, so that we can
2580 * queue requests here and wait for their completion.
2582 static void idetape_setup(ide_drive_t *drive, idetape_tape_t *tape, int minor)
2588 u16 *ctl = (u16 *)&tape->caps[12];
2590 spin_lock_init(&tape->lock);
2591 drive->dsc_overlap = 1;
2592 if (drive->hwif->host_flags & IDE_HFLAG_NO_DSC) {
2593 printk(KERN_INFO "ide-tape: %s: disabling DSC overlap\n",
2595 drive->dsc_overlap = 0;
2597 /* Seagate Travan drives do not support DSC overlap. */
2598 if (strstr(drive->id->model, "Seagate STT3401"))
2599 drive->dsc_overlap = 0;
2600 tape->minor = minor;
2601 tape->name[0] = 'h';
2602 tape->name[1] = 't';
2603 tape->name[2] = '0' + minor;
2604 tape->chrdev_dir = IDETAPE_DIR_NONE;
2605 tape->pc = tape->pc_stack;
2606 *((unsigned short *) &gcw) = drive->id->config;
2608 /* Command packet DRQ type */
2609 if (((gcw[0] & 0x60) >> 5) == 1)
2610 set_bit(IDETAPE_FLAG_DRQ_INTERRUPT, &tape->flags);
2612 idetape_get_inquiry_results(drive);
2613 idetape_get_mode_sense_results(drive);
2614 ide_tape_get_bsize_from_bdesc(drive);
2615 tape->user_bs_factor = 1;
2616 tape->buffer_size = *ctl * tape->blk_size;
2617 while (tape->buffer_size > 0xffff) {
2618 printk(KERN_NOTICE "ide-tape: decreasing stage size\n");
2620 tape->buffer_size = *ctl * tape->blk_size;
2622 buffer_size = tape->buffer_size;
2623 tape->pages_per_buffer = buffer_size / PAGE_SIZE;
2624 if (buffer_size % PAGE_SIZE) {
2625 tape->pages_per_buffer++;
2626 tape->excess_bh_size = PAGE_SIZE - buffer_size % PAGE_SIZE;
2629 /* select the "best" DSC read/write polling freq */
2630 speed = max(*(u16 *)&tape->caps[14], *(u16 *)&tape->caps[8]);
2632 t = (IDETAPE_FIFO_THRESHOLD * tape->buffer_size * HZ) / (speed * 1000);
2635 * Ensure that the number we got makes sense; limit it within
2636 * IDETAPE_DSC_RW_MIN and IDETAPE_DSC_RW_MAX.
2638 tape->best_dsc_rw_freq = clamp_t(unsigned long, t, IDETAPE_DSC_RW_MIN,
2639 IDETAPE_DSC_RW_MAX);
2640 printk(KERN_INFO "ide-tape: %s <-> %s: %dKBps, %d*%dkB buffer, "
2642 drive->name, tape->name, *(u16 *)&tape->caps[14],
2643 (*(u16 *)&tape->caps[16] * 512) / tape->buffer_size,
2644 tape->buffer_size / 1024,
2645 tape->best_dsc_rw_freq * 1000 / HZ,
2646 drive->using_dma ? ", DMA":"");
2648 idetape_add_settings(drive);
2651 static void ide_tape_remove(ide_drive_t *drive)
2653 idetape_tape_t *tape = drive->driver_data;
2655 ide_proc_unregister_driver(drive, tape->driver);
2657 ide_unregister_region(tape->disk);
2662 static void ide_tape_release(struct kref *kref)
2664 struct ide_tape_obj *tape = to_ide_tape(kref);
2665 ide_drive_t *drive = tape->drive;
2666 struct gendisk *g = tape->disk;
2668 BUG_ON(tape->merge_bh_size);
2670 drive->dsc_overlap = 0;
2671 drive->driver_data = NULL;
2672 device_destroy(idetape_sysfs_class, MKDEV(IDETAPE_MAJOR, tape->minor));
2673 device_destroy(idetape_sysfs_class,
2674 MKDEV(IDETAPE_MAJOR, tape->minor + 128));
2675 idetape_devs[tape->minor] = NULL;
2676 g->private_data = NULL;
2681 #ifdef CONFIG_IDE_PROC_FS
2682 static int proc_idetape_read_name
2683 (char *page, char **start, off_t off, int count, int *eof, void *data)
2685 ide_drive_t *drive = (ide_drive_t *) data;
2686 idetape_tape_t *tape = drive->driver_data;
2690 len = sprintf(out, "%s\n", tape->name);
2691 PROC_IDE_READ_RETURN(page, start, off, count, eof, len);
2694 static ide_proc_entry_t idetape_proc[] = {
2695 { "capacity", S_IFREG|S_IRUGO, proc_ide_read_capacity, NULL },
2696 { "name", S_IFREG|S_IRUGO, proc_idetape_read_name, NULL },
2697 { NULL, 0, NULL, NULL }
2701 static int ide_tape_probe(ide_drive_t *);
2703 static ide_driver_t idetape_driver = {
2705 .owner = THIS_MODULE,
2707 .bus = &ide_bus_type,
2709 .probe = ide_tape_probe,
2710 .remove = ide_tape_remove,
2711 .version = IDETAPE_VERSION,
2713 .supports_dsc_overlap = 1,
2714 .do_request = idetape_do_request,
2715 .end_request = idetape_end_request,
2716 .error = __ide_error,
2717 .abort = __ide_abort,
2718 #ifdef CONFIG_IDE_PROC_FS
2719 .proc = idetape_proc,
2723 /* Our character device supporting functions, passed to register_chrdev. */
2724 static const struct file_operations idetape_fops = {
2725 .owner = THIS_MODULE,
2726 .read = idetape_chrdev_read,
2727 .write = idetape_chrdev_write,
2728 .ioctl = idetape_chrdev_ioctl,
2729 .open = idetape_chrdev_open,
2730 .release = idetape_chrdev_release,
2733 static int idetape_open(struct inode *inode, struct file *filp)
2735 struct gendisk *disk = inode->i_bdev->bd_disk;
2736 struct ide_tape_obj *tape;
2738 tape = ide_tape_get(disk);
2745 static int idetape_release(struct inode *inode, struct file *filp)
2747 struct gendisk *disk = inode->i_bdev->bd_disk;
2748 struct ide_tape_obj *tape = ide_tape_g(disk);
2755 static int idetape_ioctl(struct inode *inode, struct file *file,
2756 unsigned int cmd, unsigned long arg)
2758 struct block_device *bdev = inode->i_bdev;
2759 struct ide_tape_obj *tape = ide_tape_g(bdev->bd_disk);
2760 ide_drive_t *drive = tape->drive;
2761 int err = generic_ide_ioctl(drive, file, bdev, cmd, arg);
2763 err = idetape_blkdev_ioctl(drive, cmd, arg);
2767 static struct block_device_operations idetape_block_ops = {
2768 .owner = THIS_MODULE,
2769 .open = idetape_open,
2770 .release = idetape_release,
2771 .ioctl = idetape_ioctl,
2774 static int ide_tape_probe(ide_drive_t *drive)
2776 idetape_tape_t *tape;
2780 if (!strstr("ide-tape", drive->driver_req))
2782 if (!drive->present)
2784 if (drive->media != ide_tape)
2786 if (!idetape_identify_device(drive)) {
2787 printk(KERN_ERR "ide-tape: %s: not supported by this version of"
2788 " the driver\n", drive->name);
2791 tape = kzalloc(sizeof(idetape_tape_t), GFP_KERNEL);
2793 printk(KERN_ERR "ide-tape: %s: Can't allocate a tape struct\n",
2798 g = alloc_disk(1 << PARTN_BITS);
2802 ide_init_disk(g, drive);
2804 ide_proc_register_driver(drive, &idetape_driver);
2806 kref_init(&tape->kref);
2808 tape->drive = drive;
2809 tape->driver = &idetape_driver;
2812 g->private_data = &tape->driver;
2814 drive->driver_data = tape;
2816 mutex_lock(&idetape_ref_mutex);
2817 for (minor = 0; idetape_devs[minor]; minor++)
2819 idetape_devs[minor] = tape;
2820 mutex_unlock(&idetape_ref_mutex);
2822 idetape_setup(drive, tape, minor);
2824 device_create(idetape_sysfs_class, &drive->gendev,
2825 MKDEV(IDETAPE_MAJOR, minor), "%s", tape->name);
2826 device_create(idetape_sysfs_class, &drive->gendev,
2827 MKDEV(IDETAPE_MAJOR, minor + 128), "n%s", tape->name);
2829 g->fops = &idetape_block_ops;
2830 ide_register_region(g);
2840 static void __exit idetape_exit(void)
2842 driver_unregister(&idetape_driver.gen_driver);
2843 class_destroy(idetape_sysfs_class);
2844 unregister_chrdev(IDETAPE_MAJOR, "ht");
2847 static int __init idetape_init(void)
2850 idetape_sysfs_class = class_create(THIS_MODULE, "ide_tape");
2851 if (IS_ERR(idetape_sysfs_class)) {
2852 idetape_sysfs_class = NULL;
2853 printk(KERN_ERR "Unable to create sysfs class for ide tapes\n");
2858 if (register_chrdev(IDETAPE_MAJOR, "ht", &idetape_fops)) {
2859 printk(KERN_ERR "ide-tape: Failed to register chrdev"
2862 goto out_free_class;
2865 error = driver_register(&idetape_driver.gen_driver);
2867 goto out_free_driver;
2872 driver_unregister(&idetape_driver.gen_driver);
2874 class_destroy(idetape_sysfs_class);
2879 MODULE_ALIAS("ide:*m-tape*");
2880 module_init(idetape_init);
2881 module_exit(idetape_exit);
2882 MODULE_ALIAS_CHARDEV_MAJOR(IDETAPE_MAJOR);
2883 MODULE_DESCRIPTION("ATAPI Streaming TAPE Driver");
2884 MODULE_LICENSE("GPL");