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),
59 /* IRQ handler (always log debug info if debugging is on) */
60 DBG_PC_INTR = (1 << 5),
63 /* define to see debug info */
64 #define IDETAPE_DEBUG_LOG 0
67 #define debug_log(lvl, fmt, args...) \
69 if ((lvl & DBG_PC_INTR) || (tape->debug_mask & lvl)) \
70 printk(KERN_INFO "ide-tape: " fmt, ## args); \
73 #define debug_log(lvl, fmt, args...) do {} while (0)
76 /**************************** Tunable parameters *****************************/
78 * After each failed packet command we issue a request sense command and retry
79 * the packet command IDETAPE_MAX_PC_RETRIES times.
81 * Setting IDETAPE_MAX_PC_RETRIES to 0 will disable retries.
83 #define IDETAPE_MAX_PC_RETRIES 3
86 * With each packet command, we allocate a buffer of IDETAPE_PC_BUFFER_SIZE
87 * bytes. This is used for several packet commands (Not for READ/WRITE commands)
89 #define IDETAPE_PC_BUFFER_SIZE 256
92 * In various places in the driver, we need to allocate storage
93 * for packet commands and requests, which will remain valid while
94 * we leave the driver to wait for an interrupt or a timeout event.
96 #define IDETAPE_PC_STACK (10 + IDETAPE_MAX_PC_RETRIES)
99 * Some drives (for example, Seagate STT3401A Travan) require a very long
100 * timeout, because they don't return an interrupt or clear their busy bit
101 * until after the command completes (even retension commands).
103 #define IDETAPE_WAIT_CMD (900*HZ)
106 * The following parameter is used to select the point in the internal tape fifo
107 * in which we will start to refill the buffer. Decreasing the following
108 * parameter will improve the system's latency and interactive response, while
109 * using a high value might improve system throughput.
111 #define IDETAPE_FIFO_THRESHOLD 2
114 * DSC polling parameters.
116 * Polling for DSC (a single bit in the status register) is a very important
117 * function in ide-tape. There are two cases in which we poll for DSC:
119 * 1. Before a read/write packet command, to ensure that we can transfer data
120 * from/to the tape's data buffers, without causing an actual media access.
121 * In case the tape is not ready yet, we take out our request from the device
122 * request queue, so that ide.c could service requests from the other device
123 * on the same interface in the meantime.
125 * 2. After the successful initialization of a "media access packet command",
126 * which is a command that can take a long time to complete (the interval can
127 * range from several seconds to even an hour). Again, we postpone our request
128 * in the middle to free the bus for the other device. The polling frequency
129 * here should be lower than the read/write frequency since those media access
130 * commands are slow. We start from a "fast" frequency - IDETAPE_DSC_MA_FAST
131 * (1 second), and if we don't receive DSC after IDETAPE_DSC_MA_THRESHOLD
132 * (5 min), we switch it to a lower frequency - IDETAPE_DSC_MA_SLOW (1 min).
134 * We also set a timeout for the timer, in case something goes wrong. The
135 * timeout should be longer then the maximum execution time of a tape operation.
139 #define IDETAPE_DSC_RW_MIN 5*HZ/100 /* 50 msec */
140 #define IDETAPE_DSC_RW_MAX 40*HZ/100 /* 400 msec */
141 #define IDETAPE_DSC_RW_TIMEOUT 2*60*HZ /* 2 minutes */
142 #define IDETAPE_DSC_MA_FAST 2*HZ /* 2 seconds */
143 #define IDETAPE_DSC_MA_THRESHOLD 5*60*HZ /* 5 minutes */
144 #define IDETAPE_DSC_MA_SLOW 30*HZ /* 30 seconds */
145 #define IDETAPE_DSC_MA_TIMEOUT 2*60*60*HZ /* 2 hours */
147 /*************************** End of tunable parameters ***********************/
149 /* tape directions */
151 IDETAPE_DIR_NONE = (1 << 0),
152 IDETAPE_DIR_READ = (1 << 1),
153 IDETAPE_DIR_WRITE = (1 << 2),
159 struct idetape_bh *b_reqnext;
163 /* Tape door status */
164 #define DOOR_UNLOCKED 0
165 #define DOOR_LOCKED 1
166 #define DOOR_EXPLICITLY_LOCKED 2
168 /* Some defines for the SPACE command */
169 #define IDETAPE_SPACE_OVER_FILEMARK 1
170 #define IDETAPE_SPACE_TO_EOD 3
172 /* Some defines for the LOAD UNLOAD command */
173 #define IDETAPE_LU_LOAD_MASK 1
174 #define IDETAPE_LU_RETENSION_MASK 2
175 #define IDETAPE_LU_EOT_MASK 4
178 * Special requests for our block device strategy routine.
180 * In order to service a character device command, we add special requests to
181 * the tail of our block device request queue and wait for their completion.
185 REQ_IDETAPE_PC1 = (1 << 0), /* packet command (first stage) */
186 REQ_IDETAPE_PC2 = (1 << 1), /* packet command (second stage) */
187 REQ_IDETAPE_READ = (1 << 2),
188 REQ_IDETAPE_WRITE = (1 << 3),
191 /* Error codes returned in rq->errors to the higher part of the driver. */
192 #define IDETAPE_ERROR_GENERAL 101
193 #define IDETAPE_ERROR_FILEMARK 102
194 #define IDETAPE_ERROR_EOD 103
196 /* Structures related to the SELECT SENSE / MODE SENSE packet commands. */
197 #define IDETAPE_BLOCK_DESCRIPTOR 0
198 #define IDETAPE_CAPABILITIES_PAGE 0x2a
200 /* Tape flag bits values. */
202 IDETAPE_FLAG_IGNORE_DSC = (1 << 0),
203 /* 0 When the tape position is unknown */
204 IDETAPE_FLAG_ADDRESS_VALID = (1 << 1),
205 /* Device already opened */
206 IDETAPE_FLAG_BUSY = (1 << 2),
207 /* Attempt to auto-detect the current user block size */
208 IDETAPE_FLAG_DETECT_BS = (1 << 3),
209 /* Currently on a filemark */
210 IDETAPE_FLAG_FILEMARK = (1 << 4),
211 /* DRQ interrupt device */
212 IDETAPE_FLAG_DRQ_INTERRUPT = (1 << 5),
213 /* 0 = no tape is loaded, so we don't rewind after ejecting */
214 IDETAPE_FLAG_MEDIUM_PRESENT = (1 << 6),
218 * Most of our global data which we need to save even as we leave the driver due
219 * to an interrupt or a timer event is stored in the struct defined below.
221 typedef struct ide_tape_obj {
223 ide_driver_t *driver;
224 struct gendisk *disk;
228 * Since a typical character device operation requires more
229 * than one packet command, we provide here enough memory
230 * for the maximum of interconnected packet commands.
231 * The packet commands are stored in the circular array pc_stack.
232 * pc_stack_index points to the last used entry, and warps around
233 * to the start when we get to the last array entry.
235 * pc points to the current processed packet command.
237 * failed_pc points to the last failed packet command, or contains
238 * NULL if we do not need to retry any packet command. This is
239 * required since an additional packet command is needed before the
240 * retry, to get detailed information on what went wrong.
242 /* Current packet command */
243 struct ide_atapi_pc *pc;
244 /* Last failed packet command */
245 struct ide_atapi_pc *failed_pc;
246 /* Packet command stack */
247 struct ide_atapi_pc pc_stack[IDETAPE_PC_STACK];
248 /* Next free packet command storage space */
250 struct request rq_stack[IDETAPE_PC_STACK];
251 /* We implement a circular array */
255 * DSC polling variables.
257 * While polling for DSC we use postponed_rq to postpone the current
258 * request so that ide.c will be able to service pending requests on the
259 * other device. Note that at most we will have only one DSC (usually
260 * data transfer) request in the device request queue.
262 struct request *postponed_rq;
263 /* The time in which we started polling for DSC */
264 unsigned long dsc_polling_start;
265 /* Timer used to poll for dsc */
266 struct timer_list dsc_timer;
267 /* Read/Write dsc polling frequency */
268 unsigned long best_dsc_rw_freq;
269 unsigned long dsc_poll_freq;
270 unsigned long dsc_timeout;
272 /* Read position information */
275 unsigned int first_frame;
277 /* Last error information */
278 u8 sense_key, asc, ascq;
280 /* Character device operation */
284 /* Current character device data transfer direction */
287 /* tape block size, usually 512 or 1024 bytes */
288 unsigned short blk_size;
291 /* Copy of the tape's Capabilities and Mechanical Page */
295 * Active data transfer request parameters.
297 * At most, there is only one ide-tape originated data transfer request
298 * in the device request queue. This allows ide.c to easily service
299 * requests from the other device when we postpone our active request.
302 /* Data buffer size chosen based on the tape's recommendation */
305 struct idetape_bh *merge_bh;
306 /* size of the merge buffer */
308 /* pointer to current buffer head within the merge buffer */
309 struct idetape_bh *bh;
313 int pages_per_buffer;
314 /* Wasted space in each stage */
317 /* Status/Action flags: long for set_bit */
319 /* protects the ide-tape queue */
322 /* Measures average tape speed */
323 unsigned long avg_time;
327 /* the door is currently locked */
329 /* the tape hardware is write protected */
331 /* the tape is write protected (hardware or opened as read-only) */
337 static DEFINE_MUTEX(idetape_ref_mutex);
339 static struct class *idetape_sysfs_class;
341 #define to_ide_tape(obj) container_of(obj, struct ide_tape_obj, kref)
343 #define ide_tape_g(disk) \
344 container_of((disk)->private_data, struct ide_tape_obj, driver)
346 static struct ide_tape_obj *ide_tape_get(struct gendisk *disk)
348 struct ide_tape_obj *tape = NULL;
350 mutex_lock(&idetape_ref_mutex);
351 tape = ide_tape_g(disk);
353 kref_get(&tape->kref);
354 mutex_unlock(&idetape_ref_mutex);
358 static void ide_tape_release(struct kref *);
360 static void ide_tape_put(struct ide_tape_obj *tape)
362 mutex_lock(&idetape_ref_mutex);
363 kref_put(&tape->kref, ide_tape_release);
364 mutex_unlock(&idetape_ref_mutex);
368 * The variables below are used for the character device interface. Additional
369 * state variables are defined in our ide_drive_t structure.
371 static struct ide_tape_obj *idetape_devs[MAX_HWIFS * MAX_DRIVES];
373 #define ide_tape_f(file) ((file)->private_data)
375 static struct ide_tape_obj *ide_tape_chrdev_get(unsigned int i)
377 struct ide_tape_obj *tape = NULL;
379 mutex_lock(&idetape_ref_mutex);
380 tape = idetape_devs[i];
382 kref_get(&tape->kref);
383 mutex_unlock(&idetape_ref_mutex);
387 static void idetape_input_buffers(ide_drive_t *drive, struct ide_atapi_pc *pc,
390 struct idetape_bh *bh = pc->bh;
395 printk(KERN_ERR "ide-tape: bh == NULL in "
396 "idetape_input_buffers\n");
397 ide_pad_transfer(drive, 0, bcount);
401 (unsigned int)(bh->b_size - atomic_read(&bh->b_count)),
403 drive->hwif->input_data(drive, NULL, bh->b_data +
404 atomic_read(&bh->b_count), count);
406 atomic_add(count, &bh->b_count);
407 if (atomic_read(&bh->b_count) == bh->b_size) {
410 atomic_set(&bh->b_count, 0);
416 static void idetape_output_buffers(ide_drive_t *drive, struct ide_atapi_pc *pc,
419 struct idetape_bh *bh = pc->bh;
424 printk(KERN_ERR "ide-tape: bh == NULL in %s\n",
428 count = min((unsigned int)pc->b_count, (unsigned int)bcount);
429 drive->hwif->output_data(drive, NULL, pc->b_data, count);
432 pc->b_count -= count;
437 pc->b_data = bh->b_data;
438 pc->b_count = atomic_read(&bh->b_count);
444 static void idetape_update_buffers(struct ide_atapi_pc *pc)
446 struct idetape_bh *bh = pc->bh;
448 unsigned int bcount = pc->xferred;
450 if (pc->flags & PC_FLAG_WRITING)
454 printk(KERN_ERR "ide-tape: bh == NULL in %s\n",
458 count = min((unsigned int)bh->b_size, (unsigned int)bcount);
459 atomic_set(&bh->b_count, count);
460 if (atomic_read(&bh->b_count) == bh->b_size)
468 * idetape_next_pc_storage returns a pointer to a place in which we can
469 * safely store a packet command, even though we intend to leave the
470 * driver. A storage space for a maximum of IDETAPE_PC_STACK packet
471 * commands is allocated at initialization time.
473 static struct ide_atapi_pc *idetape_next_pc_storage(ide_drive_t *drive)
475 idetape_tape_t *tape = drive->driver_data;
477 debug_log(DBG_PCRQ_STACK, "pc_stack_index=%d\n", tape->pc_stack_index);
479 if (tape->pc_stack_index == IDETAPE_PC_STACK)
480 tape->pc_stack_index = 0;
481 return (&tape->pc_stack[tape->pc_stack_index++]);
485 * idetape_next_rq_storage is used along with idetape_next_pc_storage.
486 * Since we queue packet commands in the request queue, we need to
487 * allocate a request, along with the allocation of a packet command.
490 /**************************************************************
492 * This should get fixed to use kmalloc(.., GFP_ATOMIC) *
493 * followed later on by kfree(). -ml *
495 **************************************************************/
497 static struct request *idetape_next_rq_storage(ide_drive_t *drive)
499 idetape_tape_t *tape = drive->driver_data;
501 debug_log(DBG_PCRQ_STACK, "rq_stack_index=%d\n", tape->rq_stack_index);
503 if (tape->rq_stack_index == IDETAPE_PC_STACK)
504 tape->rq_stack_index = 0;
505 return (&tape->rq_stack[tape->rq_stack_index++]);
509 * called on each failed packet command retry to analyze the request sense. We
510 * currently do not utilize this information.
512 static void idetape_analyze_error(ide_drive_t *drive, u8 *sense)
514 idetape_tape_t *tape = drive->driver_data;
515 struct ide_atapi_pc *pc = tape->failed_pc;
517 tape->sense_key = sense[2] & 0xF;
518 tape->asc = sense[12];
519 tape->ascq = sense[13];
521 debug_log(DBG_ERR, "pc = %x, sense key = %x, asc = %x, ascq = %x\n",
522 pc->c[0], tape->sense_key, tape->asc, tape->ascq);
524 /* Correct pc->xferred by asking the tape. */
525 if (pc->flags & PC_FLAG_DMA_ERROR) {
526 pc->xferred = pc->req_xfer -
528 get_unaligned_be32(&sense[3]);
529 idetape_update_buffers(pc);
533 * If error was the result of a zero-length read or write command,
534 * with sense key=5, asc=0x22, ascq=0, let it slide. Some drives
535 * (i.e. Seagate STT3401A Travan) don't support 0-length read/writes.
537 if ((pc->c[0] == READ_6 || pc->c[0] == WRITE_6)
539 && pc->c[4] == 0 && pc->c[3] == 0 && pc->c[2] == 0) {
540 if (tape->sense_key == 5) {
541 /* don't report an error, everything's ok */
543 /* don't retry read/write */
544 pc->flags |= PC_FLAG_ABORT;
547 if (pc->c[0] == READ_6 && (sense[2] & 0x80)) {
548 pc->error = IDETAPE_ERROR_FILEMARK;
549 pc->flags |= PC_FLAG_ABORT;
551 if (pc->c[0] == WRITE_6) {
552 if ((sense[2] & 0x40) || (tape->sense_key == 0xd
553 && tape->asc == 0x0 && tape->ascq == 0x2)) {
554 pc->error = IDETAPE_ERROR_EOD;
555 pc->flags |= PC_FLAG_ABORT;
558 if (pc->c[0] == READ_6 || pc->c[0] == WRITE_6) {
559 if (tape->sense_key == 8) {
560 pc->error = IDETAPE_ERROR_EOD;
561 pc->flags |= PC_FLAG_ABORT;
563 if (!(pc->flags & PC_FLAG_ABORT) &&
565 pc->retries = IDETAPE_MAX_PC_RETRIES + 1;
569 /* Free data buffers completely. */
570 static void ide_tape_kfree_buffer(idetape_tape_t *tape)
572 struct idetape_bh *prev_bh, *bh = tape->merge_bh;
575 u32 size = bh->b_size;
578 unsigned int order = fls(size >> PAGE_SHIFT)-1;
581 free_pages((unsigned long)bh->b_data, order);
584 bh->b_data += (1 << order) * PAGE_SIZE;
590 kfree(tape->merge_bh);
593 static int idetape_end_request(ide_drive_t *drive, int uptodate, int nr_sects)
595 struct request *rq = HWGROUP(drive)->rq;
596 idetape_tape_t *tape = drive->driver_data;
600 debug_log(DBG_PROCS, "Enter %s\n", __func__);
603 case 0: error = IDETAPE_ERROR_GENERAL; break;
604 case 1: error = 0; break;
605 default: error = uptodate;
609 tape->failed_pc = NULL;
611 if (!blk_special_request(rq)) {
612 ide_end_request(drive, uptodate, nr_sects);
616 spin_lock_irqsave(&tape->lock, flags);
618 ide_end_drive_cmd(drive, 0, 0);
620 spin_unlock_irqrestore(&tape->lock, flags);
624 static void ide_tape_callback(ide_drive_t *drive)
626 idetape_tape_t *tape = drive->driver_data;
627 struct ide_atapi_pc *pc = tape->pc;
628 int uptodate = pc->error ? 0 : 1;
630 debug_log(DBG_PROCS, "Enter %s\n", __func__);
632 if (tape->failed_pc == pc)
633 tape->failed_pc = NULL;
635 if (pc->c[0] == REQUEST_SENSE) {
637 idetape_analyze_error(drive, pc->buf);
639 printk(KERN_ERR "ide-tape: Error in REQUEST SENSE "
640 "itself - Aborting request!\n");
641 } else if (pc->c[0] == READ_6 || pc->c[0] == WRITE_6) {
642 struct request *rq = drive->hwif->hwgroup->rq;
643 int blocks = pc->xferred / tape->blk_size;
645 tape->avg_size += blocks * tape->blk_size;
647 if (time_after_eq(jiffies, tape->avg_time + HZ)) {
648 tape->avg_speed = tape->avg_size * HZ /
649 (jiffies - tape->avg_time) / 1024;
651 tape->avg_time = jiffies;
654 tape->first_frame += blocks;
655 rq->current_nr_sectors -= blocks;
658 uptodate = pc->error;
659 } else if (pc->c[0] == READ_POSITION && uptodate) {
660 u8 *readpos = tape->pc->buf;
662 debug_log(DBG_SENSE, "BOP - %s\n",
663 (readpos[0] & 0x80) ? "Yes" : "No");
664 debug_log(DBG_SENSE, "EOP - %s\n",
665 (readpos[0] & 0x40) ? "Yes" : "No");
667 if (readpos[0] & 0x4) {
668 printk(KERN_INFO "ide-tape: Block location is unknown"
670 clear_bit(IDETAPE_FLAG_ADDRESS_VALID, &tape->flags);
673 debug_log(DBG_SENSE, "Block Location - %u\n",
674 be32_to_cpu(*(u32 *)&readpos[4]));
676 tape->partition = readpos[1];
677 tape->first_frame = be32_to_cpu(*(u32 *)&readpos[4]);
678 set_bit(IDETAPE_FLAG_ADDRESS_VALID, &tape->flags);
682 idetape_end_request(drive, uptodate, 0);
685 static void idetape_init_pc(struct ide_atapi_pc *pc)
687 memset(pc->c, 0, 12);
691 pc->buf = pc->pc_buf;
692 pc->buf_size = IDETAPE_PC_BUFFER_SIZE;
695 pc->callback = ide_tape_callback;
698 static void idetape_create_request_sense_cmd(struct ide_atapi_pc *pc)
701 pc->c[0] = REQUEST_SENSE;
706 static void idetape_init_rq(struct request *rq, u8 cmd)
708 blk_rq_init(NULL, rq);
709 rq->cmd_type = REQ_TYPE_SPECIAL;
714 * Generate a new packet command request in front of the request queue, before
715 * the current request, so that it will be processed immediately, on the next
716 * pass through the driver. The function below is called from the request
717 * handling part of the driver (the "bottom" part). Safe storage for the request
718 * should be allocated with ide_tape_next_{pc,rq}_storage() prior to that.
720 * Memory for those requests is pre-allocated at initialization time, and is
721 * limited to IDETAPE_PC_STACK requests. We assume that we have enough space for
722 * the maximum possible number of inter-dependent packet commands.
724 * The higher level of the driver - The ioctl handler and the character device
725 * handling functions should queue request to the lower level part and wait for
726 * their completion using idetape_queue_pc_tail or idetape_queue_rw_tail.
728 static void idetape_queue_pc_head(ide_drive_t *drive, struct ide_atapi_pc *pc,
731 struct ide_tape_obj *tape = drive->driver_data;
733 idetape_init_rq(rq, REQ_IDETAPE_PC1);
734 rq->cmd_flags |= REQ_PREEMPT;
735 rq->buffer = (char *) pc;
736 rq->rq_disk = tape->disk;
737 ide_do_drive_cmd(drive, rq);
741 * idetape_retry_pc is called when an error was detected during the
742 * last packet command. We queue a request sense packet command in
743 * the head of the request list.
745 static void idetape_retry_pc(ide_drive_t *drive)
747 idetape_tape_t *tape = drive->driver_data;
748 struct ide_atapi_pc *pc;
751 (void)ide_read_error(drive);
752 pc = idetape_next_pc_storage(drive);
753 rq = idetape_next_rq_storage(drive);
754 idetape_create_request_sense_cmd(pc);
755 set_bit(IDETAPE_FLAG_IGNORE_DSC, &tape->flags);
756 idetape_queue_pc_head(drive, pc, rq);
760 * Postpone the current request so that ide.c will be able to service requests
761 * from another device on the same hwgroup while we are polling for DSC.
763 static void idetape_postpone_request(ide_drive_t *drive)
765 idetape_tape_t *tape = drive->driver_data;
767 debug_log(DBG_PROCS, "Enter %s\n", __func__);
769 tape->postponed_rq = HWGROUP(drive)->rq;
770 ide_stall_queue(drive, tape->dsc_poll_freq);
773 static void ide_tape_handle_dsc(ide_drive_t *drive)
775 idetape_tape_t *tape = drive->driver_data;
777 /* Media access command */
778 tape->dsc_polling_start = jiffies;
779 tape->dsc_poll_freq = IDETAPE_DSC_MA_FAST;
780 tape->dsc_timeout = jiffies + IDETAPE_DSC_MA_TIMEOUT;
781 /* Allow ide.c to handle other requests */
782 idetape_postpone_request(drive);
785 static void ide_tape_io_buffers(ide_drive_t *drive, struct ide_atapi_pc *pc,
786 unsigned int bcount, int write)
789 idetape_output_buffers(drive, pc, bcount);
791 idetape_input_buffers(drive, pc, bcount);
795 * This is the usual interrupt handler which will be called during a packet
796 * command. We will transfer some of the data (as requested by the drive) and
797 * will re-point interrupt handler to us. When data transfer is finished, we
798 * will act according to the algorithm described before
801 static ide_startstop_t idetape_pc_intr(ide_drive_t *drive)
803 ide_hwif_t *hwif = drive->hwif;
804 idetape_tape_t *tape = drive->driver_data;
805 struct ide_atapi_pc *pc = tape->pc;
806 xfer_func_t *xferfunc;
811 debug_log(DBG_PC_INTR, "Enter %s - interrupt handler\n", __func__);
813 /* Clear the interrupt */
814 stat = ide_read_status(drive);
816 if (pc->flags & PC_FLAG_DMA_IN_PROGRESS) {
817 if (hwif->dma_ops->dma_end(drive) || (stat & ERR_STAT)) {
818 pc->flags |= PC_FLAG_DMA_ERROR;
820 pc->xferred = pc->req_xfer;
821 idetape_update_buffers(pc);
823 debug_log(DBG_PC_INTR, "%s: DMA finished\n", drive->name);
826 /* No more interrupts */
827 if ((stat & DRQ_STAT) == 0) {
828 debug_log(DBG_PC_INTR, "Packet command completed, %d bytes"
829 " transferred\n", pc->xferred);
831 pc->flags &= ~PC_FLAG_DMA_IN_PROGRESS;
832 local_irq_enable_in_hardirq();
834 if ((stat & ERR_STAT) && pc->c[0] == REQUEST_SENSE)
836 if ((stat & ERR_STAT) || (pc->flags & PC_FLAG_DMA_ERROR)) {
838 debug_log(DBG_PC_INTR, "%s: I/O error\n", drive->name);
840 if (pc->c[0] == REQUEST_SENSE) {
841 printk(KERN_ERR "%s: I/O error in request sense"
842 " command\n", drive->name);
843 return ide_do_reset(drive);
845 debug_log(DBG_PC_INTR, "[cmd %x]: check condition\n",
848 /* Retry operation */
849 idetape_retry_pc(drive);
853 if ((pc->flags & PC_FLAG_WAIT_FOR_DSC) &&
854 (stat & SEEK_STAT) == 0) {
855 ide_tape_handle_dsc(drive);
858 /* Command finished - Call the callback function */
863 if (pc->flags & PC_FLAG_DMA_IN_PROGRESS) {
864 pc->flags &= ~PC_FLAG_DMA_IN_PROGRESS;
865 printk(KERN_ERR "%s: The device wants to issue more interrupts "
866 "in DMA mode\n", drive->name);
868 return ide_do_reset(drive);
870 /* Get the number of bytes to transfer on this interrupt. */
871 bcount = (hwif->INB(hwif->io_ports.lbah_addr) << 8) |
872 hwif->INB(hwif->io_ports.lbam_addr);
874 ireason = hwif->INB(hwif->io_ports.nsect_addr);
877 printk(KERN_ERR "%s: CoD != 0 in %s\n", drive->name, __func__);
878 return ide_do_reset(drive);
880 if (((ireason & IO) == IO) == !!(pc->flags & PC_FLAG_WRITING)) {
881 /* Hopefully, we will never get here */
882 printk(KERN_ERR "%s: We wanted to %s, but the device wants us "
883 "to %s!\n", drive->name,
884 (ireason & IO) ? "Write" : "Read",
885 (ireason & IO) ? "Read" : "Write");
886 return ide_do_reset(drive);
888 if (!(pc->flags & PC_FLAG_WRITING)) {
889 /* Reading - Check that we have enough space */
890 temp = pc->xferred + bcount;
891 if (temp > pc->req_xfer) {
892 if (temp > pc->buf_size) {
893 printk(KERN_ERR "%s: The device wants to send "
894 "us more data than expected - "
897 ide_pad_transfer(drive, 0, bcount);
898 ide_set_handler(drive, &idetape_pc_intr,
899 IDETAPE_WAIT_CMD, NULL);
902 debug_log(DBG_PC_INTR, "The device wants to send us more "
903 "data than expected - allowing transfer\n");
905 xferfunc = hwif->input_data;
907 xferfunc = hwif->output_data;
911 ide_tape_io_buffers(drive, pc, bcount,
912 !!(pc->flags & PC_FLAG_WRITING));
914 xferfunc(drive, NULL, pc->cur_pos, bcount);
916 /* Update the current position */
917 pc->xferred += bcount;
918 pc->cur_pos += bcount;
920 debug_log(DBG_PC_INTR, "[cmd %x] transferred %d bytes on that intr.\n",
923 /* And set the interrupt handler again */
924 ide_set_handler(drive, &idetape_pc_intr, IDETAPE_WAIT_CMD, NULL);
929 * Packet Command Interface
931 * The current Packet Command is available in tape->pc, and will not change
932 * until we finish handling it. Each packet command is associated with a
933 * callback function that will be called when the command is finished.
935 * The handling will be done in three stages:
937 * 1. idetape_issue_pc will send the packet command to the drive, and will set
938 * the interrupt handler to idetape_pc_intr.
940 * 2. On each interrupt, idetape_pc_intr will be called. This step will be
941 * repeated until the device signals us that no more interrupts will be issued.
943 * 3. ATAPI Tape media access commands have immediate status with a delayed
944 * process. In case of a successful initiation of a media access packet command,
945 * the DSC bit will be set when the actual execution of the command is finished.
946 * Since the tape drive will not issue an interrupt, we have to poll for this
947 * event. In this case, we define the request as "low priority request" by
948 * setting rq_status to IDETAPE_RQ_POSTPONED, set a timer to poll for DSC and
951 * ide.c will then give higher priority to requests which originate from the
952 * other device, until will change rq_status to RQ_ACTIVE.
954 * 4. When the packet command is finished, it will be checked for errors.
956 * 5. In case an error was found, we queue a request sense packet command in
957 * front of the request queue and retry the operation up to
958 * IDETAPE_MAX_PC_RETRIES times.
960 * 6. In case no error was found, or we decided to give up and not to retry
961 * again, the callback function will be called and then we will handle the next
964 static ide_startstop_t idetape_transfer_pc(ide_drive_t *drive)
966 idetape_tape_t *tape = drive->driver_data;
968 return ide_transfer_pc(drive, tape->pc, idetape_pc_intr,
969 IDETAPE_WAIT_CMD, NULL);
972 static ide_startstop_t idetape_issue_pc(ide_drive_t *drive,
973 struct ide_atapi_pc *pc)
975 idetape_tape_t *tape = drive->driver_data;
977 if (tape->pc->c[0] == REQUEST_SENSE &&
978 pc->c[0] == REQUEST_SENSE) {
979 printk(KERN_ERR "ide-tape: possible ide-tape.c bug - "
980 "Two request sense in serial were issued\n");
983 if (tape->failed_pc == NULL && pc->c[0] != REQUEST_SENSE)
984 tape->failed_pc = pc;
985 /* Set the current packet command */
988 if (pc->retries > IDETAPE_MAX_PC_RETRIES ||
989 (pc->flags & PC_FLAG_ABORT)) {
991 * We will "abort" retrying a packet command in case legitimate
992 * error code was received (crossing a filemark, or end of the
993 * media, for example).
995 if (!(pc->flags & PC_FLAG_ABORT)) {
996 if (!(pc->c[0] == TEST_UNIT_READY &&
997 tape->sense_key == 2 && tape->asc == 4 &&
998 (tape->ascq == 1 || tape->ascq == 8))) {
999 printk(KERN_ERR "ide-tape: %s: I/O error, "
1000 "pc = %2x, key = %2x, "
1001 "asc = %2x, ascq = %2x\n",
1002 tape->name, pc->c[0],
1003 tape->sense_key, tape->asc,
1007 pc->error = IDETAPE_ERROR_GENERAL;
1009 tape->failed_pc = NULL;
1010 pc->callback(drive);
1013 debug_log(DBG_SENSE, "Retry #%d, cmd = %02X\n", pc->retries, pc->c[0]);
1017 return ide_issue_pc(drive, pc, idetape_transfer_pc,
1018 IDETAPE_WAIT_CMD, NULL);
1021 /* A mode sense command is used to "sense" tape parameters. */
1022 static void idetape_create_mode_sense_cmd(struct ide_atapi_pc *pc, u8 page_code)
1024 idetape_init_pc(pc);
1025 pc->c[0] = MODE_SENSE;
1026 if (page_code != IDETAPE_BLOCK_DESCRIPTOR)
1027 /* DBD = 1 - Don't return block descriptors */
1029 pc->c[2] = page_code;
1031 * Changed pc->c[3] to 0 (255 will at best return unused info).
1033 * For SCSI this byte is defined as subpage instead of high byte
1034 * of length and some IDE drives seem to interpret it this way
1035 * and return an error when 255 is used.
1038 /* We will just discard data in that case */
1040 if (page_code == IDETAPE_BLOCK_DESCRIPTOR)
1042 else if (page_code == IDETAPE_CAPABILITIES_PAGE)
1048 static ide_startstop_t idetape_media_access_finished(ide_drive_t *drive)
1050 idetape_tape_t *tape = drive->driver_data;
1051 struct ide_atapi_pc *pc = tape->pc;
1054 stat = ide_read_status(drive);
1056 if (stat & SEEK_STAT) {
1057 if (stat & ERR_STAT) {
1058 /* Error detected */
1059 if (pc->c[0] != TEST_UNIT_READY)
1060 printk(KERN_ERR "ide-tape: %s: I/O error, ",
1062 /* Retry operation */
1063 idetape_retry_pc(drive);
1068 pc->error = IDETAPE_ERROR_GENERAL;
1069 tape->failed_pc = NULL;
1071 pc->callback(drive);
1075 static void idetape_create_read_cmd(idetape_tape_t *tape,
1076 struct ide_atapi_pc *pc,
1077 unsigned int length, struct idetape_bh *bh)
1079 idetape_init_pc(pc);
1081 put_unaligned(cpu_to_be32(length), (unsigned int *) &pc->c[1]);
1084 atomic_set(&bh->b_count, 0);
1086 pc->buf_size = length * tape->blk_size;
1087 pc->req_xfer = pc->buf_size;
1088 if (pc->req_xfer == tape->buffer_size)
1089 pc->flags |= PC_FLAG_DMA_OK;
1092 static void idetape_create_write_cmd(idetape_tape_t *tape,
1093 struct ide_atapi_pc *pc,
1094 unsigned int length, struct idetape_bh *bh)
1096 idetape_init_pc(pc);
1098 put_unaligned(cpu_to_be32(length), (unsigned int *) &pc->c[1]);
1100 pc->flags |= PC_FLAG_WRITING;
1102 pc->b_data = bh->b_data;
1103 pc->b_count = atomic_read(&bh->b_count);
1105 pc->buf_size = length * tape->blk_size;
1106 pc->req_xfer = pc->buf_size;
1107 if (pc->req_xfer == tape->buffer_size)
1108 pc->flags |= PC_FLAG_DMA_OK;
1111 static ide_startstop_t idetape_do_request(ide_drive_t *drive,
1112 struct request *rq, sector_t block)
1114 idetape_tape_t *tape = drive->driver_data;
1115 struct ide_atapi_pc *pc = NULL;
1116 struct request *postponed_rq = tape->postponed_rq;
1119 debug_log(DBG_SENSE, "sector: %ld, nr_sectors: %ld,"
1120 " current_nr_sectors: %d\n",
1121 rq->sector, rq->nr_sectors, rq->current_nr_sectors);
1123 if (!blk_special_request(rq)) {
1124 /* We do not support buffer cache originated requests. */
1125 printk(KERN_NOTICE "ide-tape: %s: Unsupported request in "
1126 "request queue (%d)\n", drive->name, rq->cmd_type);
1127 ide_end_request(drive, 0, 0);
1131 /* Retry a failed packet command */
1132 if (tape->failed_pc && tape->pc->c[0] == REQUEST_SENSE) {
1133 pc = tape->failed_pc;
1137 if (postponed_rq != NULL)
1138 if (rq != postponed_rq) {
1139 printk(KERN_ERR "ide-tape: ide-tape.c bug - "
1140 "Two DSC requests were queued\n");
1141 idetape_end_request(drive, 0, 0);
1145 tape->postponed_rq = NULL;
1148 * If the tape is still busy, postpone our request and service
1149 * the other device meanwhile.
1151 stat = ide_read_status(drive);
1153 if (!drive->dsc_overlap && !(rq->cmd[0] & REQ_IDETAPE_PC2))
1154 set_bit(IDETAPE_FLAG_IGNORE_DSC, &tape->flags);
1156 if (drive->post_reset == 1) {
1157 set_bit(IDETAPE_FLAG_IGNORE_DSC, &tape->flags);
1158 drive->post_reset = 0;
1161 if (!test_and_clear_bit(IDETAPE_FLAG_IGNORE_DSC, &tape->flags) &&
1162 (stat & SEEK_STAT) == 0) {
1163 if (postponed_rq == NULL) {
1164 tape->dsc_polling_start = jiffies;
1165 tape->dsc_poll_freq = tape->best_dsc_rw_freq;
1166 tape->dsc_timeout = jiffies + IDETAPE_DSC_RW_TIMEOUT;
1167 } else if (time_after(jiffies, tape->dsc_timeout)) {
1168 printk(KERN_ERR "ide-tape: %s: DSC timeout\n",
1170 if (rq->cmd[0] & REQ_IDETAPE_PC2) {
1171 idetape_media_access_finished(drive);
1174 return ide_do_reset(drive);
1176 } else if (time_after(jiffies,
1177 tape->dsc_polling_start +
1178 IDETAPE_DSC_MA_THRESHOLD))
1179 tape->dsc_poll_freq = IDETAPE_DSC_MA_SLOW;
1180 idetape_postpone_request(drive);
1183 if (rq->cmd[0] & REQ_IDETAPE_READ) {
1184 pc = idetape_next_pc_storage(drive);
1185 idetape_create_read_cmd(tape, pc, rq->current_nr_sectors,
1186 (struct idetape_bh *)rq->special);
1189 if (rq->cmd[0] & REQ_IDETAPE_WRITE) {
1190 pc = idetape_next_pc_storage(drive);
1191 idetape_create_write_cmd(tape, pc, rq->current_nr_sectors,
1192 (struct idetape_bh *)rq->special);
1195 if (rq->cmd[0] & REQ_IDETAPE_PC1) {
1196 pc = (struct ide_atapi_pc *) rq->buffer;
1197 rq->cmd[0] &= ~(REQ_IDETAPE_PC1);
1198 rq->cmd[0] |= REQ_IDETAPE_PC2;
1201 if (rq->cmd[0] & REQ_IDETAPE_PC2) {
1202 idetape_media_access_finished(drive);
1207 if (test_bit(IDETAPE_FLAG_DRQ_INTERRUPT, &tape->flags))
1208 pc->flags |= PC_FLAG_DRQ_INTERRUPT;
1210 return idetape_issue_pc(drive, pc);
1214 * The function below uses __get_free_pages to allocate a data buffer of size
1215 * tape->buffer_size (or a bit more). We attempt to combine sequential pages as
1218 * It returns a pointer to the newly allocated buffer, or NULL in case of
1221 static struct idetape_bh *ide_tape_kmalloc_buffer(idetape_tape_t *tape,
1222 int full, int clear)
1224 struct idetape_bh *prev_bh, *bh, *merge_bh;
1225 int pages = tape->pages_per_buffer;
1226 unsigned int order, b_allocd;
1227 char *b_data = NULL;
1229 merge_bh = kmalloc(sizeof(struct idetape_bh), GFP_KERNEL);
1234 order = fls(pages) - 1;
1235 bh->b_data = (char *) __get_free_pages(GFP_KERNEL, order);
1238 b_allocd = (1 << order) * PAGE_SIZE;
1242 memset(bh->b_data, 0, b_allocd);
1243 bh->b_reqnext = NULL;
1244 bh->b_size = b_allocd;
1245 atomic_set(&bh->b_count, full ? bh->b_size : 0);
1248 order = fls(pages) - 1;
1249 b_data = (char *) __get_free_pages(GFP_KERNEL, order);
1252 b_allocd = (1 << order) * PAGE_SIZE;
1255 memset(b_data, 0, b_allocd);
1257 /* newly allocated page frames below buffer header or ...*/
1258 if (bh->b_data == b_data + b_allocd) {
1259 bh->b_size += b_allocd;
1260 bh->b_data -= b_allocd;
1262 atomic_add(b_allocd, &bh->b_count);
1265 /* they are above the header */
1266 if (b_data == bh->b_data + bh->b_size) {
1267 bh->b_size += b_allocd;
1269 atomic_add(b_allocd, &bh->b_count);
1273 bh = kmalloc(sizeof(struct idetape_bh), GFP_KERNEL);
1275 free_pages((unsigned long) b_data, order);
1278 bh->b_reqnext = NULL;
1279 bh->b_data = b_data;
1280 bh->b_size = b_allocd;
1281 atomic_set(&bh->b_count, full ? bh->b_size : 0);
1282 prev_bh->b_reqnext = bh;
1287 bh->b_size -= tape->excess_bh_size;
1289 atomic_sub(tape->excess_bh_size, &bh->b_count);
1292 ide_tape_kfree_buffer(tape);
1296 static int idetape_copy_stage_from_user(idetape_tape_t *tape,
1297 const char __user *buf, int n)
1299 struct idetape_bh *bh = tape->bh;
1305 printk(KERN_ERR "ide-tape: bh == NULL in %s\n",
1309 count = min((unsigned int)
1310 (bh->b_size - atomic_read(&bh->b_count)),
1312 if (copy_from_user(bh->b_data + atomic_read(&bh->b_count), buf,
1316 atomic_add(count, &bh->b_count);
1318 if (atomic_read(&bh->b_count) == bh->b_size) {
1321 atomic_set(&bh->b_count, 0);
1328 static int idetape_copy_stage_to_user(idetape_tape_t *tape, char __user *buf,
1331 struct idetape_bh *bh = tape->bh;
1337 printk(KERN_ERR "ide-tape: bh == NULL in %s\n",
1341 count = min(tape->b_count, n);
1342 if (copy_to_user(buf, tape->b_data, count))
1345 tape->b_data += count;
1346 tape->b_count -= count;
1348 if (!tape->b_count) {
1352 tape->b_data = bh->b_data;
1353 tape->b_count = atomic_read(&bh->b_count);
1360 static void idetape_init_merge_buffer(idetape_tape_t *tape)
1362 struct idetape_bh *bh = tape->merge_bh;
1363 tape->bh = tape->merge_bh;
1365 if (tape->chrdev_dir == IDETAPE_DIR_WRITE)
1366 atomic_set(&bh->b_count, 0);
1368 tape->b_data = bh->b_data;
1369 tape->b_count = atomic_read(&bh->b_count);
1374 * Write a filemark if write_filemark=1. Flush the device buffers without
1375 * writing a filemark otherwise.
1377 static void idetape_create_write_filemark_cmd(ide_drive_t *drive,
1378 struct ide_atapi_pc *pc, int write_filemark)
1380 idetape_init_pc(pc);
1381 pc->c[0] = WRITE_FILEMARKS;
1382 pc->c[4] = write_filemark;
1383 pc->flags |= PC_FLAG_WAIT_FOR_DSC;
1386 static void idetape_create_test_unit_ready_cmd(struct ide_atapi_pc *pc)
1388 idetape_init_pc(pc);
1389 pc->c[0] = TEST_UNIT_READY;
1393 * We add a special packet command request to the tail of the request queue, and
1394 * wait for it to be serviced. This is not to be called from within the request
1395 * handling part of the driver! We allocate here data on the stack and it is
1396 * valid until the request is finished. This is not the case for the bottom part
1397 * of the driver, where we are always leaving the functions to wait for an
1398 * interrupt or a timer event.
1400 * From the bottom part of the driver, we should allocate safe memory using
1401 * idetape_next_pc_storage() and ide_tape_next_rq_storage(), and add the request
1402 * to the request list without waiting for it to be serviced! In that case, we
1403 * usually use idetape_queue_pc_head().
1405 static int idetape_queue_pc_tail(ide_drive_t *drive, struct ide_atapi_pc *pc)
1407 struct ide_tape_obj *tape = drive->driver_data;
1411 rq = blk_get_request(drive->queue, READ, __GFP_WAIT);
1412 rq->cmd_type = REQ_TYPE_SPECIAL;
1413 rq->cmd[0] = REQ_IDETAPE_PC1;
1414 rq->buffer = (char *)pc;
1415 error = blk_execute_rq(drive->queue, tape->disk, rq, 0);
1416 blk_put_request(rq);
1420 static void idetape_create_load_unload_cmd(ide_drive_t *drive,
1421 struct ide_atapi_pc *pc, int cmd)
1423 idetape_init_pc(pc);
1424 pc->c[0] = START_STOP;
1426 pc->flags |= PC_FLAG_WAIT_FOR_DSC;
1429 static int idetape_wait_ready(ide_drive_t *drive, unsigned long timeout)
1431 idetape_tape_t *tape = drive->driver_data;
1432 struct ide_atapi_pc pc;
1433 int load_attempted = 0;
1435 /* Wait for the tape to become ready */
1436 set_bit(IDETAPE_FLAG_MEDIUM_PRESENT, &tape->flags);
1438 while (time_before(jiffies, timeout)) {
1439 idetape_create_test_unit_ready_cmd(&pc);
1440 if (!idetape_queue_pc_tail(drive, &pc))
1442 if ((tape->sense_key == 2 && tape->asc == 4 && tape->ascq == 2)
1443 || (tape->asc == 0x3A)) {
1447 idetape_create_load_unload_cmd(drive, &pc,
1448 IDETAPE_LU_LOAD_MASK);
1449 idetape_queue_pc_tail(drive, &pc);
1451 /* not about to be ready */
1452 } else if (!(tape->sense_key == 2 && tape->asc == 4 &&
1453 (tape->ascq == 1 || tape->ascq == 8)))
1460 static int idetape_flush_tape_buffers(ide_drive_t *drive)
1462 struct ide_atapi_pc pc;
1465 idetape_create_write_filemark_cmd(drive, &pc, 0);
1466 rc = idetape_queue_pc_tail(drive, &pc);
1469 idetape_wait_ready(drive, 60 * 5 * HZ);
1473 static void idetape_create_read_position_cmd(struct ide_atapi_pc *pc)
1475 idetape_init_pc(pc);
1476 pc->c[0] = READ_POSITION;
1480 static int idetape_read_position(ide_drive_t *drive)
1482 idetape_tape_t *tape = drive->driver_data;
1483 struct ide_atapi_pc pc;
1486 debug_log(DBG_PROCS, "Enter %s\n", __func__);
1488 idetape_create_read_position_cmd(&pc);
1489 if (idetape_queue_pc_tail(drive, &pc))
1491 position = tape->first_frame;
1495 static void idetape_create_locate_cmd(ide_drive_t *drive,
1496 struct ide_atapi_pc *pc,
1497 unsigned int block, u8 partition, int skip)
1499 idetape_init_pc(pc);
1500 pc->c[0] = POSITION_TO_ELEMENT;
1502 put_unaligned(cpu_to_be32(block), (unsigned int *) &pc->c[3]);
1503 pc->c[8] = partition;
1504 pc->flags |= PC_FLAG_WAIT_FOR_DSC;
1507 static int idetape_create_prevent_cmd(ide_drive_t *drive,
1508 struct ide_atapi_pc *pc, int prevent)
1510 idetape_tape_t *tape = drive->driver_data;
1512 /* device supports locking according to capabilities page */
1513 if (!(tape->caps[6] & 0x01))
1516 idetape_init_pc(pc);
1517 pc->c[0] = ALLOW_MEDIUM_REMOVAL;
1522 static void __ide_tape_discard_merge_buffer(ide_drive_t *drive)
1524 idetape_tape_t *tape = drive->driver_data;
1526 if (tape->chrdev_dir != IDETAPE_DIR_READ)
1529 clear_bit(IDETAPE_FLAG_FILEMARK, &tape->flags);
1530 tape->merge_bh_size = 0;
1531 if (tape->merge_bh != NULL) {
1532 ide_tape_kfree_buffer(tape);
1533 tape->merge_bh = NULL;
1536 tape->chrdev_dir = IDETAPE_DIR_NONE;
1540 * Position the tape to the requested block using the LOCATE packet command.
1541 * A READ POSITION command is then issued to check where we are positioned. Like
1542 * all higher level operations, we queue the commands at the tail of the request
1543 * queue and wait for their completion.
1545 static int idetape_position_tape(ide_drive_t *drive, unsigned int block,
1546 u8 partition, int skip)
1548 idetape_tape_t *tape = drive->driver_data;
1550 struct ide_atapi_pc pc;
1552 if (tape->chrdev_dir == IDETAPE_DIR_READ)
1553 __ide_tape_discard_merge_buffer(drive);
1554 idetape_wait_ready(drive, 60 * 5 * HZ);
1555 idetape_create_locate_cmd(drive, &pc, block, partition, skip);
1556 retval = idetape_queue_pc_tail(drive, &pc);
1560 idetape_create_read_position_cmd(&pc);
1561 return (idetape_queue_pc_tail(drive, &pc));
1564 static void ide_tape_discard_merge_buffer(ide_drive_t *drive,
1565 int restore_position)
1567 idetape_tape_t *tape = drive->driver_data;
1570 __ide_tape_discard_merge_buffer(drive);
1571 if (restore_position) {
1572 position = idetape_read_position(drive);
1573 seek = position > 0 ? position : 0;
1574 if (idetape_position_tape(drive, seek, 0, 0)) {
1575 printk(KERN_INFO "ide-tape: %s: position_tape failed in"
1576 " %s\n", tape->name, __func__);
1583 * Generate a read/write request for the block device interface and wait for it
1586 static int idetape_queue_rw_tail(ide_drive_t *drive, int cmd, int blocks,
1587 struct idetape_bh *bh)
1589 idetape_tape_t *tape = drive->driver_data;
1593 debug_log(DBG_SENSE, "%s: cmd=%d\n", __func__, cmd);
1595 rq = blk_get_request(drive->queue, READ, __GFP_WAIT);
1596 rq->cmd_type = REQ_TYPE_SPECIAL;
1598 rq->rq_disk = tape->disk;
1599 rq->special = (void *)bh;
1600 rq->sector = tape->first_frame;
1601 rq->nr_sectors = blocks;
1602 rq->current_nr_sectors = blocks;
1603 blk_execute_rq(drive->queue, tape->disk, rq, 0);
1605 errors = rq->errors;
1606 ret = tape->blk_size * (blocks - rq->current_nr_sectors);
1607 blk_put_request(rq);
1609 if ((cmd & (REQ_IDETAPE_READ | REQ_IDETAPE_WRITE)) == 0)
1613 idetape_init_merge_buffer(tape);
1614 if (errors == IDETAPE_ERROR_GENERAL)
1619 static void idetape_create_inquiry_cmd(struct ide_atapi_pc *pc)
1621 idetape_init_pc(pc);
1627 static void idetape_create_rewind_cmd(ide_drive_t *drive,
1628 struct ide_atapi_pc *pc)
1630 idetape_init_pc(pc);
1631 pc->c[0] = REZERO_UNIT;
1632 pc->flags |= PC_FLAG_WAIT_FOR_DSC;
1635 static void idetape_create_erase_cmd(struct ide_atapi_pc *pc)
1637 idetape_init_pc(pc);
1640 pc->flags |= PC_FLAG_WAIT_FOR_DSC;
1643 static void idetape_create_space_cmd(struct ide_atapi_pc *pc, int count, u8 cmd)
1645 idetape_init_pc(pc);
1647 put_unaligned(cpu_to_be32(count), (unsigned int *) &pc->c[1]);
1649 pc->flags |= PC_FLAG_WAIT_FOR_DSC;
1652 /* Queue up a character device originated write request. */
1653 static int idetape_add_chrdev_write_request(ide_drive_t *drive, int blocks)
1655 idetape_tape_t *tape = drive->driver_data;
1657 debug_log(DBG_CHRDEV, "Enter %s\n", __func__);
1659 return idetape_queue_rw_tail(drive, REQ_IDETAPE_WRITE,
1660 blocks, tape->merge_bh);
1663 static void ide_tape_flush_merge_buffer(ide_drive_t *drive)
1665 idetape_tape_t *tape = drive->driver_data;
1667 struct idetape_bh *bh;
1669 if (tape->chrdev_dir != IDETAPE_DIR_WRITE) {
1670 printk(KERN_ERR "ide-tape: bug: Trying to empty merge buffer"
1671 " but we are not writing.\n");
1674 if (tape->merge_bh_size > tape->buffer_size) {
1675 printk(KERN_ERR "ide-tape: bug: merge_buffer too big\n");
1676 tape->merge_bh_size = tape->buffer_size;
1678 if (tape->merge_bh_size) {
1679 blocks = tape->merge_bh_size / tape->blk_size;
1680 if (tape->merge_bh_size % tape->blk_size) {
1684 i = tape->blk_size - tape->merge_bh_size %
1686 bh = tape->bh->b_reqnext;
1688 atomic_set(&bh->b_count, 0);
1694 printk(KERN_INFO "ide-tape: bug,"
1698 min = min(i, (unsigned int)(bh->b_size -
1699 atomic_read(&bh->b_count)));
1700 memset(bh->b_data + atomic_read(&bh->b_count),
1702 atomic_add(min, &bh->b_count);
1707 (void) idetape_add_chrdev_write_request(drive, blocks);
1708 tape->merge_bh_size = 0;
1710 if (tape->merge_bh != NULL) {
1711 ide_tape_kfree_buffer(tape);
1712 tape->merge_bh = NULL;
1714 tape->chrdev_dir = IDETAPE_DIR_NONE;
1717 static int idetape_init_read(ide_drive_t *drive)
1719 idetape_tape_t *tape = drive->driver_data;
1722 /* Initialize read operation */
1723 if (tape->chrdev_dir != IDETAPE_DIR_READ) {
1724 if (tape->chrdev_dir == IDETAPE_DIR_WRITE) {
1725 ide_tape_flush_merge_buffer(drive);
1726 idetape_flush_tape_buffers(drive);
1728 if (tape->merge_bh || tape->merge_bh_size) {
1729 printk(KERN_ERR "ide-tape: merge_bh_size should be"
1731 tape->merge_bh_size = 0;
1733 tape->merge_bh = ide_tape_kmalloc_buffer(tape, 0, 0);
1734 if (!tape->merge_bh)
1736 tape->chrdev_dir = IDETAPE_DIR_READ;
1739 * Issue a read 0 command to ensure that DSC handshake is
1740 * switched from completion mode to buffer available mode.
1741 * No point in issuing this if DSC overlap isn't supported, some
1742 * drives (Seagate STT3401A) will return an error.
1744 if (drive->dsc_overlap) {
1745 bytes_read = idetape_queue_rw_tail(drive,
1746 REQ_IDETAPE_READ, 0,
1748 if (bytes_read < 0) {
1749 ide_tape_kfree_buffer(tape);
1750 tape->merge_bh = NULL;
1751 tape->chrdev_dir = IDETAPE_DIR_NONE;
1760 /* called from idetape_chrdev_read() to service a chrdev read request. */
1761 static int idetape_add_chrdev_read_request(ide_drive_t *drive, int blocks)
1763 idetape_tape_t *tape = drive->driver_data;
1765 debug_log(DBG_PROCS, "Enter %s, %d blocks\n", __func__, blocks);
1767 /* If we are at a filemark, return a read length of 0 */
1768 if (test_bit(IDETAPE_FLAG_FILEMARK, &tape->flags))
1771 idetape_init_read(drive);
1773 return idetape_queue_rw_tail(drive, REQ_IDETAPE_READ, blocks,
1777 static void idetape_pad_zeros(ide_drive_t *drive, int bcount)
1779 idetape_tape_t *tape = drive->driver_data;
1780 struct idetape_bh *bh;
1786 bh = tape->merge_bh;
1787 count = min(tape->buffer_size, bcount);
1789 blocks = count / tape->blk_size;
1791 atomic_set(&bh->b_count,
1792 min(count, (unsigned int)bh->b_size));
1793 memset(bh->b_data, 0, atomic_read(&bh->b_count));
1794 count -= atomic_read(&bh->b_count);
1797 idetape_queue_rw_tail(drive, REQ_IDETAPE_WRITE, blocks,
1803 * Rewinds the tape to the Beginning Of the current Partition (BOP). We
1804 * currently support only one partition.
1806 static int idetape_rewind_tape(ide_drive_t *drive)
1809 struct ide_atapi_pc pc;
1810 idetape_tape_t *tape;
1811 tape = drive->driver_data;
1813 debug_log(DBG_SENSE, "Enter %s\n", __func__);
1815 idetape_create_rewind_cmd(drive, &pc);
1816 retval = idetape_queue_pc_tail(drive, &pc);
1820 idetape_create_read_position_cmd(&pc);
1821 retval = idetape_queue_pc_tail(drive, &pc);
1827 /* mtio.h compatible commands should be issued to the chrdev interface. */
1828 static int idetape_blkdev_ioctl(ide_drive_t *drive, unsigned int cmd,
1831 idetape_tape_t *tape = drive->driver_data;
1832 void __user *argp = (void __user *)arg;
1834 struct idetape_config {
1835 int dsc_rw_frequency;
1836 int dsc_media_access_frequency;
1840 debug_log(DBG_PROCS, "Enter %s\n", __func__);
1844 if (copy_from_user(&config, argp, sizeof(config)))
1846 tape->best_dsc_rw_freq = config.dsc_rw_frequency;
1849 config.dsc_rw_frequency = (int) tape->best_dsc_rw_freq;
1850 config.nr_stages = 1;
1851 if (copy_to_user(argp, &config, sizeof(config)))
1860 static int idetape_space_over_filemarks(ide_drive_t *drive, short mt_op,
1863 idetape_tape_t *tape = drive->driver_data;
1864 struct ide_atapi_pc pc;
1865 int retval, count = 0;
1866 int sprev = !!(tape->caps[4] & 0x20);
1870 if (MTBSF == mt_op || MTBSFM == mt_op) {
1873 mt_count = -mt_count;
1876 if (tape->chrdev_dir == IDETAPE_DIR_READ) {
1877 tape->merge_bh_size = 0;
1878 if (test_and_clear_bit(IDETAPE_FLAG_FILEMARK, &tape->flags))
1880 ide_tape_discard_merge_buffer(drive, 0);
1886 idetape_create_space_cmd(&pc, mt_count - count,
1887 IDETAPE_SPACE_OVER_FILEMARK);
1888 return idetape_queue_pc_tail(drive, &pc);
1893 retval = idetape_space_over_filemarks(drive, MTFSF,
1897 count = (MTBSFM == mt_op ? 1 : -1);
1898 return idetape_space_over_filemarks(drive, MTFSF, count);
1900 printk(KERN_ERR "ide-tape: MTIO operation %d not supported\n",
1907 * Our character device read / write functions.
1909 * The tape is optimized to maximize throughput when it is transferring an
1910 * integral number of the "continuous transfer limit", which is a parameter of
1911 * the specific tape (26kB on my particular tape, 32kB for Onstream).
1913 * As of version 1.3 of the driver, the character device provides an abstract
1914 * continuous view of the media - any mix of block sizes (even 1 byte) on the
1915 * same backup/restore procedure is supported. The driver will internally
1916 * convert the requests to the recommended transfer unit, so that an unmatch
1917 * between the user's block size to the recommended size will only result in a
1918 * (slightly) increased driver overhead, but will no longer hit performance.
1919 * This is not applicable to Onstream.
1921 static ssize_t idetape_chrdev_read(struct file *file, char __user *buf,
1922 size_t count, loff_t *ppos)
1924 struct ide_tape_obj *tape = ide_tape_f(file);
1925 ide_drive_t *drive = tape->drive;
1926 ssize_t bytes_read, temp, actually_read = 0, rc;
1928 u16 ctl = *(u16 *)&tape->caps[12];
1930 debug_log(DBG_CHRDEV, "Enter %s, count %Zd\n", __func__, count);
1932 if (tape->chrdev_dir != IDETAPE_DIR_READ) {
1933 if (test_bit(IDETAPE_FLAG_DETECT_BS, &tape->flags))
1934 if (count > tape->blk_size &&
1935 (count % tape->blk_size) == 0)
1936 tape->user_bs_factor = count / tape->blk_size;
1938 rc = idetape_init_read(drive);
1943 if (tape->merge_bh_size) {
1944 actually_read = min((unsigned int)(tape->merge_bh_size),
1945 (unsigned int)count);
1946 if (idetape_copy_stage_to_user(tape, buf, actually_read))
1948 buf += actually_read;
1949 tape->merge_bh_size -= actually_read;
1950 count -= actually_read;
1952 while (count >= tape->buffer_size) {
1953 bytes_read = idetape_add_chrdev_read_request(drive, ctl);
1954 if (bytes_read <= 0)
1956 if (idetape_copy_stage_to_user(tape, buf, bytes_read))
1959 count -= bytes_read;
1960 actually_read += bytes_read;
1963 bytes_read = idetape_add_chrdev_read_request(drive, ctl);
1964 if (bytes_read <= 0)
1966 temp = min((unsigned long)count, (unsigned long)bytes_read);
1967 if (idetape_copy_stage_to_user(tape, buf, temp))
1969 actually_read += temp;
1970 tape->merge_bh_size = bytes_read-temp;
1973 if (!actually_read && test_bit(IDETAPE_FLAG_FILEMARK, &tape->flags)) {
1974 debug_log(DBG_SENSE, "%s: spacing over filemark\n", tape->name);
1976 idetape_space_over_filemarks(drive, MTFSF, 1);
1980 return ret ? ret : actually_read;
1983 static ssize_t idetape_chrdev_write(struct file *file, const char __user *buf,
1984 size_t count, loff_t *ppos)
1986 struct ide_tape_obj *tape = ide_tape_f(file);
1987 ide_drive_t *drive = tape->drive;
1988 ssize_t actually_written = 0;
1990 u16 ctl = *(u16 *)&tape->caps[12];
1992 /* The drive is write protected. */
1993 if (tape->write_prot)
1996 debug_log(DBG_CHRDEV, "Enter %s, count %Zd\n", __func__, count);
1998 /* Initialize write operation */
1999 if (tape->chrdev_dir != IDETAPE_DIR_WRITE) {
2000 if (tape->chrdev_dir == IDETAPE_DIR_READ)
2001 ide_tape_discard_merge_buffer(drive, 1);
2002 if (tape->merge_bh || tape->merge_bh_size) {
2003 printk(KERN_ERR "ide-tape: merge_bh_size "
2004 "should be 0 now\n");
2005 tape->merge_bh_size = 0;
2007 tape->merge_bh = ide_tape_kmalloc_buffer(tape, 0, 0);
2008 if (!tape->merge_bh)
2010 tape->chrdev_dir = IDETAPE_DIR_WRITE;
2011 idetape_init_merge_buffer(tape);
2014 * Issue a write 0 command to ensure that DSC handshake is
2015 * switched from completion mode to buffer available mode. No
2016 * point in issuing this if DSC overlap isn't supported, some
2017 * drives (Seagate STT3401A) will return an error.
2019 if (drive->dsc_overlap) {
2020 ssize_t retval = idetape_queue_rw_tail(drive,
2021 REQ_IDETAPE_WRITE, 0,
2024 ide_tape_kfree_buffer(tape);
2025 tape->merge_bh = NULL;
2026 tape->chrdev_dir = IDETAPE_DIR_NONE;
2033 if (tape->merge_bh_size) {
2034 if (tape->merge_bh_size >= tape->buffer_size) {
2035 printk(KERN_ERR "ide-tape: bug: merge buf too big\n");
2036 tape->merge_bh_size = 0;
2038 actually_written = min((unsigned int)
2039 (tape->buffer_size - tape->merge_bh_size),
2040 (unsigned int)count);
2041 if (idetape_copy_stage_from_user(tape, buf, actually_written))
2043 buf += actually_written;
2044 tape->merge_bh_size += actually_written;
2045 count -= actually_written;
2047 if (tape->merge_bh_size == tape->buffer_size) {
2049 tape->merge_bh_size = 0;
2050 retval = idetape_add_chrdev_write_request(drive, ctl);
2055 while (count >= tape->buffer_size) {
2057 if (idetape_copy_stage_from_user(tape, buf, tape->buffer_size))
2059 buf += tape->buffer_size;
2060 count -= tape->buffer_size;
2061 retval = idetape_add_chrdev_write_request(drive, ctl);
2062 actually_written += tape->buffer_size;
2067 actually_written += count;
2068 if (idetape_copy_stage_from_user(tape, buf, count))
2070 tape->merge_bh_size += count;
2072 return ret ? ret : actually_written;
2075 static int idetape_write_filemark(ide_drive_t *drive)
2077 struct ide_atapi_pc pc;
2079 /* Write a filemark */
2080 idetape_create_write_filemark_cmd(drive, &pc, 1);
2081 if (idetape_queue_pc_tail(drive, &pc)) {
2082 printk(KERN_ERR "ide-tape: Couldn't write a filemark\n");
2089 * Called from idetape_chrdev_ioctl when the general mtio MTIOCTOP ioctl is
2092 * Note: MTBSF and MTBSFM are not supported when the tape doesn't support
2093 * spacing over filemarks in the reverse direction. In this case, MTFSFM is also
2094 * usually not supported.
2096 * The following commands are currently not supported:
2098 * MTFSS, MTBSS, MTWSM, MTSETDENSITY, MTSETDRVBUFFER, MT_ST_BOOLEANS,
2099 * MT_ST_WRITE_THRESHOLD.
2101 static int idetape_mtioctop(ide_drive_t *drive, short mt_op, int mt_count)
2103 idetape_tape_t *tape = drive->driver_data;
2104 struct ide_atapi_pc pc;
2107 debug_log(DBG_ERR, "Handling MTIOCTOP ioctl: mt_op=%d, mt_count=%d\n",
2117 return idetape_space_over_filemarks(drive, mt_op, mt_count);
2124 if (tape->write_prot)
2126 ide_tape_discard_merge_buffer(drive, 1);
2127 for (i = 0; i < mt_count; i++) {
2128 retval = idetape_write_filemark(drive);
2134 ide_tape_discard_merge_buffer(drive, 0);
2135 if (idetape_rewind_tape(drive))
2139 ide_tape_discard_merge_buffer(drive, 0);
2140 idetape_create_load_unload_cmd(drive, &pc,
2141 IDETAPE_LU_LOAD_MASK);
2142 return idetape_queue_pc_tail(drive, &pc);
2146 * If door is locked, attempt to unlock before
2147 * attempting to eject.
2149 if (tape->door_locked) {
2150 if (idetape_create_prevent_cmd(drive, &pc, 0))
2151 if (!idetape_queue_pc_tail(drive, &pc))
2152 tape->door_locked = DOOR_UNLOCKED;
2154 ide_tape_discard_merge_buffer(drive, 0);
2155 idetape_create_load_unload_cmd(drive, &pc,
2156 !IDETAPE_LU_LOAD_MASK);
2157 retval = idetape_queue_pc_tail(drive, &pc);
2159 clear_bit(IDETAPE_FLAG_MEDIUM_PRESENT, &tape->flags);
2162 ide_tape_discard_merge_buffer(drive, 0);
2163 return idetape_flush_tape_buffers(drive);
2165 ide_tape_discard_merge_buffer(drive, 0);
2166 idetape_create_load_unload_cmd(drive, &pc,
2167 IDETAPE_LU_RETENSION_MASK | IDETAPE_LU_LOAD_MASK);
2168 return idetape_queue_pc_tail(drive, &pc);
2170 idetape_create_space_cmd(&pc, 0, IDETAPE_SPACE_TO_EOD);
2171 return idetape_queue_pc_tail(drive, &pc);
2173 (void)idetape_rewind_tape(drive);
2174 idetape_create_erase_cmd(&pc);
2175 return idetape_queue_pc_tail(drive, &pc);
2178 if (mt_count < tape->blk_size ||
2179 mt_count % tape->blk_size)
2181 tape->user_bs_factor = mt_count / tape->blk_size;
2182 clear_bit(IDETAPE_FLAG_DETECT_BS, &tape->flags);
2184 set_bit(IDETAPE_FLAG_DETECT_BS, &tape->flags);
2187 ide_tape_discard_merge_buffer(drive, 0);
2188 return idetape_position_tape(drive,
2189 mt_count * tape->user_bs_factor, tape->partition, 0);
2191 ide_tape_discard_merge_buffer(drive, 0);
2192 return idetape_position_tape(drive, 0, mt_count, 0);
2196 if (!idetape_create_prevent_cmd(drive, &pc, 1))
2198 retval = idetape_queue_pc_tail(drive, &pc);
2201 tape->door_locked = DOOR_EXPLICITLY_LOCKED;
2204 if (!idetape_create_prevent_cmd(drive, &pc, 0))
2206 retval = idetape_queue_pc_tail(drive, &pc);
2209 tape->door_locked = DOOR_UNLOCKED;
2212 printk(KERN_ERR "ide-tape: MTIO operation %d not supported\n",
2219 * Our character device ioctls. General mtio.h magnetic io commands are
2220 * supported here, and not in the corresponding block interface. Our own
2221 * ide-tape ioctls are supported on both interfaces.
2223 static int idetape_chrdev_ioctl(struct inode *inode, struct file *file,
2224 unsigned int cmd, unsigned long arg)
2226 struct ide_tape_obj *tape = ide_tape_f(file);
2227 ide_drive_t *drive = tape->drive;
2231 int block_offset = 0, position = tape->first_frame;
2232 void __user *argp = (void __user *)arg;
2234 debug_log(DBG_CHRDEV, "Enter %s, cmd=%u\n", __func__, cmd);
2236 if (tape->chrdev_dir == IDETAPE_DIR_WRITE) {
2237 ide_tape_flush_merge_buffer(drive);
2238 idetape_flush_tape_buffers(drive);
2240 if (cmd == MTIOCGET || cmd == MTIOCPOS) {
2241 block_offset = tape->merge_bh_size /
2242 (tape->blk_size * tape->user_bs_factor);
2243 position = idetape_read_position(drive);
2249 if (copy_from_user(&mtop, argp, sizeof(struct mtop)))
2251 return idetape_mtioctop(drive, mtop.mt_op, mtop.mt_count);
2253 memset(&mtget, 0, sizeof(struct mtget));
2254 mtget.mt_type = MT_ISSCSI2;
2255 mtget.mt_blkno = position / tape->user_bs_factor - block_offset;
2257 ((tape->blk_size * tape->user_bs_factor)
2258 << MT_ST_BLKSIZE_SHIFT) & MT_ST_BLKSIZE_MASK;
2260 if (tape->drv_write_prot)
2261 mtget.mt_gstat |= GMT_WR_PROT(0xffffffff);
2263 if (copy_to_user(argp, &mtget, sizeof(struct mtget)))
2267 mtpos.mt_blkno = position / tape->user_bs_factor - block_offset;
2268 if (copy_to_user(argp, &mtpos, sizeof(struct mtpos)))
2272 if (tape->chrdev_dir == IDETAPE_DIR_READ)
2273 ide_tape_discard_merge_buffer(drive, 1);
2274 return idetape_blkdev_ioctl(drive, cmd, arg);
2279 * Do a mode sense page 0 with block descriptor and if it succeeds set the tape
2280 * block size with the reported value.
2282 static void ide_tape_get_bsize_from_bdesc(ide_drive_t *drive)
2284 idetape_tape_t *tape = drive->driver_data;
2285 struct ide_atapi_pc pc;
2287 idetape_create_mode_sense_cmd(&pc, IDETAPE_BLOCK_DESCRIPTOR);
2288 if (idetape_queue_pc_tail(drive, &pc)) {
2289 printk(KERN_ERR "ide-tape: Can't get block descriptor\n");
2290 if (tape->blk_size == 0) {
2291 printk(KERN_WARNING "ide-tape: Cannot deal with zero "
2292 "block size, assuming 32k\n");
2293 tape->blk_size = 32768;
2297 tape->blk_size = (pc.buf[4 + 5] << 16) +
2298 (pc.buf[4 + 6] << 8) +
2300 tape->drv_write_prot = (pc.buf[2] & 0x80) >> 7;
2303 static int idetape_chrdev_open(struct inode *inode, struct file *filp)
2305 unsigned int minor = iminor(inode), i = minor & ~0xc0;
2307 idetape_tape_t *tape;
2308 struct ide_atapi_pc pc;
2311 if (i >= MAX_HWIFS * MAX_DRIVES)
2314 tape = ide_tape_chrdev_get(i);
2318 debug_log(DBG_CHRDEV, "Enter %s\n", __func__);
2321 * We really want to do nonseekable_open(inode, filp); here, but some
2322 * versions of tar incorrectly call lseek on tapes and bail out if that
2323 * fails. So we disallow pread() and pwrite(), but permit lseeks.
2325 filp->f_mode &= ~(FMODE_PREAD | FMODE_PWRITE);
2327 drive = tape->drive;
2329 filp->private_data = tape;
2331 if (test_and_set_bit(IDETAPE_FLAG_BUSY, &tape->flags)) {
2336 retval = idetape_wait_ready(drive, 60 * HZ);
2338 clear_bit(IDETAPE_FLAG_BUSY, &tape->flags);
2339 printk(KERN_ERR "ide-tape: %s: drive not ready\n", tape->name);
2343 idetape_read_position(drive);
2344 if (!test_bit(IDETAPE_FLAG_ADDRESS_VALID, &tape->flags))
2345 (void)idetape_rewind_tape(drive);
2347 /* Read block size and write protect status from drive. */
2348 ide_tape_get_bsize_from_bdesc(drive);
2350 /* Set write protect flag if device is opened as read-only. */
2351 if ((filp->f_flags & O_ACCMODE) == O_RDONLY)
2352 tape->write_prot = 1;
2354 tape->write_prot = tape->drv_write_prot;
2356 /* Make sure drive isn't write protected if user wants to write. */
2357 if (tape->write_prot) {
2358 if ((filp->f_flags & O_ACCMODE) == O_WRONLY ||
2359 (filp->f_flags & O_ACCMODE) == O_RDWR) {
2360 clear_bit(IDETAPE_FLAG_BUSY, &tape->flags);
2366 /* Lock the tape drive door so user can't eject. */
2367 if (tape->chrdev_dir == IDETAPE_DIR_NONE) {
2368 if (idetape_create_prevent_cmd(drive, &pc, 1)) {
2369 if (!idetape_queue_pc_tail(drive, &pc)) {
2370 if (tape->door_locked != DOOR_EXPLICITLY_LOCKED)
2371 tape->door_locked = DOOR_LOCKED;
2382 static void idetape_write_release(ide_drive_t *drive, unsigned int minor)
2384 idetape_tape_t *tape = drive->driver_data;
2386 ide_tape_flush_merge_buffer(drive);
2387 tape->merge_bh = ide_tape_kmalloc_buffer(tape, 1, 0);
2388 if (tape->merge_bh != NULL) {
2389 idetape_pad_zeros(drive, tape->blk_size *
2390 (tape->user_bs_factor - 1));
2391 ide_tape_kfree_buffer(tape);
2392 tape->merge_bh = NULL;
2394 idetape_write_filemark(drive);
2395 idetape_flush_tape_buffers(drive);
2396 idetape_flush_tape_buffers(drive);
2399 static int idetape_chrdev_release(struct inode *inode, struct file *filp)
2401 struct ide_tape_obj *tape = ide_tape_f(filp);
2402 ide_drive_t *drive = tape->drive;
2403 struct ide_atapi_pc pc;
2404 unsigned int minor = iminor(inode);
2407 tape = drive->driver_data;
2409 debug_log(DBG_CHRDEV, "Enter %s\n", __func__);
2411 if (tape->chrdev_dir == IDETAPE_DIR_WRITE)
2412 idetape_write_release(drive, minor);
2413 if (tape->chrdev_dir == IDETAPE_DIR_READ) {
2415 ide_tape_discard_merge_buffer(drive, 1);
2418 if (minor < 128 && test_bit(IDETAPE_FLAG_MEDIUM_PRESENT, &tape->flags))
2419 (void) idetape_rewind_tape(drive);
2420 if (tape->chrdev_dir == IDETAPE_DIR_NONE) {
2421 if (tape->door_locked == DOOR_LOCKED) {
2422 if (idetape_create_prevent_cmd(drive, &pc, 0)) {
2423 if (!idetape_queue_pc_tail(drive, &pc))
2424 tape->door_locked = DOOR_UNLOCKED;
2428 clear_bit(IDETAPE_FLAG_BUSY, &tape->flags);
2435 * check the contents of the ATAPI IDENTIFY command results. We return:
2437 * 1 - If the tape can be supported by us, based on the information we have so
2440 * 0 - If this tape driver is not currently supported by us.
2442 static int idetape_identify_device(ide_drive_t *drive)
2444 u8 gcw[2], protocol, device_type, removable, packet_size;
2446 if (drive->id_read == 0)
2449 *((unsigned short *) &gcw) = drive->id->config;
2451 protocol = (gcw[1] & 0xC0) >> 6;
2452 device_type = gcw[1] & 0x1F;
2453 removable = !!(gcw[0] & 0x80);
2454 packet_size = gcw[0] & 0x3;
2456 /* Check that we can support this device */
2458 printk(KERN_ERR "ide-tape: Protocol (0x%02x) is not ATAPI\n",
2460 else if (device_type != 1)
2461 printk(KERN_ERR "ide-tape: Device type (0x%02x) is not set "
2462 "to tape\n", device_type);
2463 else if (!removable)
2464 printk(KERN_ERR "ide-tape: The removable flag is not set\n");
2465 else if (packet_size != 0) {
2466 printk(KERN_ERR "ide-tape: Packet size (0x%02x) is not 12"
2467 " bytes\n", packet_size);
2473 static void idetape_get_inquiry_results(ide_drive_t *drive)
2475 idetape_tape_t *tape = drive->driver_data;
2476 struct ide_atapi_pc pc;
2477 char fw_rev[6], vendor_id[10], product_id[18];
2479 idetape_create_inquiry_cmd(&pc);
2480 if (idetape_queue_pc_tail(drive, &pc)) {
2481 printk(KERN_ERR "ide-tape: %s: can't get INQUIRY results\n",
2485 memcpy(vendor_id, &pc.buf[8], 8);
2486 memcpy(product_id, &pc.buf[16], 16);
2487 memcpy(fw_rev, &pc.buf[32], 4);
2489 ide_fixstring(vendor_id, 10, 0);
2490 ide_fixstring(product_id, 18, 0);
2491 ide_fixstring(fw_rev, 6, 0);
2493 printk(KERN_INFO "ide-tape: %s <-> %s: %s %s rev %s\n",
2494 drive->name, tape->name, vendor_id, product_id, fw_rev);
2498 * Ask the tape about its various parameters. In particular, we will adjust our
2499 * data transfer buffer size to the recommended value as returned by the tape.
2501 static void idetape_get_mode_sense_results(ide_drive_t *drive)
2503 idetape_tape_t *tape = drive->driver_data;
2504 struct ide_atapi_pc pc;
2506 u8 speed, max_speed;
2508 idetape_create_mode_sense_cmd(&pc, IDETAPE_CAPABILITIES_PAGE);
2509 if (idetape_queue_pc_tail(drive, &pc)) {
2510 printk(KERN_ERR "ide-tape: Can't get tape parameters - assuming"
2511 " some default values\n");
2512 tape->blk_size = 512;
2513 put_unaligned(52, (u16 *)&tape->caps[12]);
2514 put_unaligned(540, (u16 *)&tape->caps[14]);
2515 put_unaligned(6*52, (u16 *)&tape->caps[16]);
2518 caps = pc.buf + 4 + pc.buf[3];
2520 /* convert to host order and save for later use */
2521 speed = be16_to_cpu(*(u16 *)&caps[14]);
2522 max_speed = be16_to_cpu(*(u16 *)&caps[8]);
2524 put_unaligned(max_speed, (u16 *)&caps[8]);
2525 put_unaligned(be16_to_cpu(*(u16 *)&caps[12]), (u16 *)&caps[12]);
2526 put_unaligned(speed, (u16 *)&caps[14]);
2527 put_unaligned(be16_to_cpu(*(u16 *)&caps[16]), (u16 *)&caps[16]);
2530 printk(KERN_INFO "ide-tape: %s: invalid tape speed "
2531 "(assuming 650KB/sec)\n", drive->name);
2532 put_unaligned(650, (u16 *)&caps[14]);
2535 printk(KERN_INFO "ide-tape: %s: invalid max_speed "
2536 "(assuming 650KB/sec)\n", drive->name);
2537 put_unaligned(650, (u16 *)&caps[8]);
2540 memcpy(&tape->caps, caps, 20);
2542 tape->blk_size = 512;
2543 else if (caps[7] & 0x04)
2544 tape->blk_size = 1024;
2547 #ifdef CONFIG_IDE_PROC_FS
2548 static void idetape_add_settings(ide_drive_t *drive)
2550 idetape_tape_t *tape = drive->driver_data;
2552 ide_add_setting(drive, "buffer", SETTING_READ, TYPE_SHORT, 0, 0xffff,
2553 1, 2, (u16 *)&tape->caps[16], NULL);
2554 ide_add_setting(drive, "speed", SETTING_READ, TYPE_SHORT, 0, 0xffff,
2555 1, 1, (u16 *)&tape->caps[14], NULL);
2556 ide_add_setting(drive, "buffer_size", SETTING_READ, TYPE_INT, 0, 0xffff,
2557 1, 1024, &tape->buffer_size, NULL);
2558 ide_add_setting(drive, "tdsc", SETTING_RW, TYPE_INT, IDETAPE_DSC_RW_MIN,
2559 IDETAPE_DSC_RW_MAX, 1000, HZ, &tape->best_dsc_rw_freq,
2561 ide_add_setting(drive, "dsc_overlap", SETTING_RW, TYPE_BYTE, 0, 1, 1,
2562 1, &drive->dsc_overlap, NULL);
2563 ide_add_setting(drive, "avg_speed", SETTING_READ, TYPE_INT, 0, 0xffff,
2564 1, 1, &tape->avg_speed, NULL);
2565 ide_add_setting(drive, "debug_mask", SETTING_RW, TYPE_INT, 0, 0xffff, 1,
2566 1, &tape->debug_mask, NULL);
2569 static inline void idetape_add_settings(ide_drive_t *drive) { ; }
2573 * The function below is called to:
2575 * 1. Initialize our various state variables.
2576 * 2. Ask the tape for its capabilities.
2577 * 3. Allocate a buffer which will be used for data transfer. The buffer size
2578 * is chosen based on the recommendation which we received in step 2.
2580 * Note that at this point ide.c already assigned us an irq, so that we can
2581 * queue requests here and wait for their completion.
2583 static void idetape_setup(ide_drive_t *drive, idetape_tape_t *tape, int minor)
2589 u16 *ctl = (u16 *)&tape->caps[12];
2591 spin_lock_init(&tape->lock);
2592 drive->dsc_overlap = 1;
2593 if (drive->hwif->host_flags & IDE_HFLAG_NO_DSC) {
2594 printk(KERN_INFO "ide-tape: %s: disabling DSC overlap\n",
2596 drive->dsc_overlap = 0;
2598 /* Seagate Travan drives do not support DSC overlap. */
2599 if (strstr(drive->id->model, "Seagate STT3401"))
2600 drive->dsc_overlap = 0;
2601 tape->minor = minor;
2602 tape->name[0] = 'h';
2603 tape->name[1] = 't';
2604 tape->name[2] = '0' + minor;
2605 tape->chrdev_dir = IDETAPE_DIR_NONE;
2606 tape->pc = tape->pc_stack;
2607 *((unsigned short *) &gcw) = drive->id->config;
2609 /* Command packet DRQ type */
2610 if (((gcw[0] & 0x60) >> 5) == 1)
2611 set_bit(IDETAPE_FLAG_DRQ_INTERRUPT, &tape->flags);
2613 idetape_get_inquiry_results(drive);
2614 idetape_get_mode_sense_results(drive);
2615 ide_tape_get_bsize_from_bdesc(drive);
2616 tape->user_bs_factor = 1;
2617 tape->buffer_size = *ctl * tape->blk_size;
2618 while (tape->buffer_size > 0xffff) {
2619 printk(KERN_NOTICE "ide-tape: decreasing stage size\n");
2621 tape->buffer_size = *ctl * tape->blk_size;
2623 buffer_size = tape->buffer_size;
2624 tape->pages_per_buffer = buffer_size / PAGE_SIZE;
2625 if (buffer_size % PAGE_SIZE) {
2626 tape->pages_per_buffer++;
2627 tape->excess_bh_size = PAGE_SIZE - buffer_size % PAGE_SIZE;
2630 /* select the "best" DSC read/write polling freq */
2631 speed = max(*(u16 *)&tape->caps[14], *(u16 *)&tape->caps[8]);
2633 t = (IDETAPE_FIFO_THRESHOLD * tape->buffer_size * HZ) / (speed * 1000);
2636 * Ensure that the number we got makes sense; limit it within
2637 * IDETAPE_DSC_RW_MIN and IDETAPE_DSC_RW_MAX.
2639 tape->best_dsc_rw_freq = clamp_t(unsigned long, t, IDETAPE_DSC_RW_MIN,
2640 IDETAPE_DSC_RW_MAX);
2641 printk(KERN_INFO "ide-tape: %s <-> %s: %dKBps, %d*%dkB buffer, "
2643 drive->name, tape->name, *(u16 *)&tape->caps[14],
2644 (*(u16 *)&tape->caps[16] * 512) / tape->buffer_size,
2645 tape->buffer_size / 1024,
2646 tape->best_dsc_rw_freq * 1000 / HZ,
2647 drive->using_dma ? ", DMA":"");
2649 idetape_add_settings(drive);
2652 static void ide_tape_remove(ide_drive_t *drive)
2654 idetape_tape_t *tape = drive->driver_data;
2656 ide_proc_unregister_driver(drive, tape->driver);
2658 ide_unregister_region(tape->disk);
2663 static void ide_tape_release(struct kref *kref)
2665 struct ide_tape_obj *tape = to_ide_tape(kref);
2666 ide_drive_t *drive = tape->drive;
2667 struct gendisk *g = tape->disk;
2669 BUG_ON(tape->merge_bh_size);
2671 drive->dsc_overlap = 0;
2672 drive->driver_data = NULL;
2673 device_destroy(idetape_sysfs_class, MKDEV(IDETAPE_MAJOR, tape->minor));
2674 device_destroy(idetape_sysfs_class,
2675 MKDEV(IDETAPE_MAJOR, tape->minor + 128));
2676 idetape_devs[tape->minor] = NULL;
2677 g->private_data = NULL;
2682 #ifdef CONFIG_IDE_PROC_FS
2683 static int proc_idetape_read_name
2684 (char *page, char **start, off_t off, int count, int *eof, void *data)
2686 ide_drive_t *drive = (ide_drive_t *) data;
2687 idetape_tape_t *tape = drive->driver_data;
2691 len = sprintf(out, "%s\n", tape->name);
2692 PROC_IDE_READ_RETURN(page, start, off, count, eof, len);
2695 static ide_proc_entry_t idetape_proc[] = {
2696 { "capacity", S_IFREG|S_IRUGO, proc_ide_read_capacity, NULL },
2697 { "name", S_IFREG|S_IRUGO, proc_idetape_read_name, NULL },
2698 { NULL, 0, NULL, NULL }
2702 static int ide_tape_probe(ide_drive_t *);
2704 static ide_driver_t idetape_driver = {
2706 .owner = THIS_MODULE,
2708 .bus = &ide_bus_type,
2710 .probe = ide_tape_probe,
2711 .remove = ide_tape_remove,
2712 .version = IDETAPE_VERSION,
2714 .supports_dsc_overlap = 1,
2715 .do_request = idetape_do_request,
2716 .end_request = idetape_end_request,
2717 .error = __ide_error,
2718 .abort = __ide_abort,
2719 #ifdef CONFIG_IDE_PROC_FS
2720 .proc = idetape_proc,
2724 /* Our character device supporting functions, passed to register_chrdev. */
2725 static const struct file_operations idetape_fops = {
2726 .owner = THIS_MODULE,
2727 .read = idetape_chrdev_read,
2728 .write = idetape_chrdev_write,
2729 .ioctl = idetape_chrdev_ioctl,
2730 .open = idetape_chrdev_open,
2731 .release = idetape_chrdev_release,
2734 static int idetape_open(struct inode *inode, struct file *filp)
2736 struct gendisk *disk = inode->i_bdev->bd_disk;
2737 struct ide_tape_obj *tape;
2739 tape = ide_tape_get(disk);
2746 static int idetape_release(struct inode *inode, struct file *filp)
2748 struct gendisk *disk = inode->i_bdev->bd_disk;
2749 struct ide_tape_obj *tape = ide_tape_g(disk);
2756 static int idetape_ioctl(struct inode *inode, struct file *file,
2757 unsigned int cmd, unsigned long arg)
2759 struct block_device *bdev = inode->i_bdev;
2760 struct ide_tape_obj *tape = ide_tape_g(bdev->bd_disk);
2761 ide_drive_t *drive = tape->drive;
2762 int err = generic_ide_ioctl(drive, file, bdev, cmd, arg);
2764 err = idetape_blkdev_ioctl(drive, cmd, arg);
2768 static struct block_device_operations idetape_block_ops = {
2769 .owner = THIS_MODULE,
2770 .open = idetape_open,
2771 .release = idetape_release,
2772 .ioctl = idetape_ioctl,
2775 static int ide_tape_probe(ide_drive_t *drive)
2777 idetape_tape_t *tape;
2781 if (!strstr("ide-tape", drive->driver_req))
2783 if (!drive->present)
2785 if (drive->media != ide_tape)
2787 if (!idetape_identify_device(drive)) {
2788 printk(KERN_ERR "ide-tape: %s: not supported by this version of"
2789 " the driver\n", drive->name);
2792 tape = kzalloc(sizeof(idetape_tape_t), GFP_KERNEL);
2794 printk(KERN_ERR "ide-tape: %s: Can't allocate a tape struct\n",
2799 g = alloc_disk(1 << PARTN_BITS);
2803 ide_init_disk(g, drive);
2805 ide_proc_register_driver(drive, &idetape_driver);
2807 kref_init(&tape->kref);
2809 tape->drive = drive;
2810 tape->driver = &idetape_driver;
2813 g->private_data = &tape->driver;
2815 drive->driver_data = tape;
2817 mutex_lock(&idetape_ref_mutex);
2818 for (minor = 0; idetape_devs[minor]; minor++)
2820 idetape_devs[minor] = tape;
2821 mutex_unlock(&idetape_ref_mutex);
2823 idetape_setup(drive, tape, minor);
2825 device_create(idetape_sysfs_class, &drive->gendev,
2826 MKDEV(IDETAPE_MAJOR, minor), "%s", tape->name);
2827 device_create(idetape_sysfs_class, &drive->gendev,
2828 MKDEV(IDETAPE_MAJOR, minor + 128), "n%s", tape->name);
2830 g->fops = &idetape_block_ops;
2831 ide_register_region(g);
2841 static void __exit idetape_exit(void)
2843 driver_unregister(&idetape_driver.gen_driver);
2844 class_destroy(idetape_sysfs_class);
2845 unregister_chrdev(IDETAPE_MAJOR, "ht");
2848 static int __init idetape_init(void)
2851 idetape_sysfs_class = class_create(THIS_MODULE, "ide_tape");
2852 if (IS_ERR(idetape_sysfs_class)) {
2853 idetape_sysfs_class = NULL;
2854 printk(KERN_ERR "Unable to create sysfs class for ide tapes\n");
2859 if (register_chrdev(IDETAPE_MAJOR, "ht", &idetape_fops)) {
2860 printk(KERN_ERR "ide-tape: Failed to register chrdev"
2863 goto out_free_class;
2866 error = driver_register(&idetape_driver.gen_driver);
2868 goto out_free_driver;
2873 driver_unregister(&idetape_driver.gen_driver);
2875 class_destroy(idetape_sysfs_class);
2880 MODULE_ALIAS("ide:*m-tape*");
2881 module_init(idetape_init);
2882 module_exit(idetape_exit);
2883 MODULE_ALIAS_CHARDEV_MAJOR(IDETAPE_MAJOR);
2884 MODULE_DESCRIPTION("ATAPI Streaming TAPE Driver");
2885 MODULE_LICENSE("GPL");