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 "1.19"
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>
43 #include <asm/uaccess.h>
45 #include <asm/unaligned.h>
46 #include <linux/mtio.h>
48 /**************************** Tunable parameters *****************************/
52 * Pipelined mode parameters.
54 * We try to use the minimum number of stages which is enough to
55 * keep the tape constantly streaming. To accomplish that, we implement
56 * a feedback loop around the maximum number of stages:
58 * We start from MIN maximum stages (we will not even use MIN stages
59 * if we don't need them), increment it by RATE*(MAX-MIN)
60 * whenever we sense that the pipeline is empty, until we reach
61 * the optimum value or until we reach MAX.
63 * Setting the following parameter to 0 is illegal: the pipelined mode
64 * cannot be disabled (calculate_speeds() divides by tape->max_stages.)
66 #define IDETAPE_MIN_PIPELINE_STAGES 1
67 #define IDETAPE_MAX_PIPELINE_STAGES 400
68 #define IDETAPE_INCREASE_STAGES_RATE 20
71 * The following are used to debug the driver:
73 * Setting IDETAPE_DEBUG_LOG to 1 will log driver flow control.
75 * Setting them to 0 will restore normal operation mode:
77 * 1. Disable logging normal successful operations.
78 * 2. Disable self-sanity checks.
79 * 3. Errors will still be logged, of course.
81 * All the #if DEBUG code will be removed some day, when the driver
82 * is verified to be stable enough. This will make it much more
85 #define IDETAPE_DEBUG_LOG 0
88 * After each failed packet command we issue a request sense command
89 * and retry the packet command IDETAPE_MAX_PC_RETRIES times.
91 * Setting IDETAPE_MAX_PC_RETRIES to 0 will disable retries.
93 #define IDETAPE_MAX_PC_RETRIES 3
96 * With each packet command, we allocate a buffer of
97 * IDETAPE_PC_BUFFER_SIZE bytes. This is used for several packet
98 * commands (Not for READ/WRITE commands).
100 #define IDETAPE_PC_BUFFER_SIZE 256
103 * In various places in the driver, we need to allocate storage
104 * for packet commands and requests, which will remain valid while
105 * we leave the driver to wait for an interrupt or a timeout event.
107 #define IDETAPE_PC_STACK (10 + IDETAPE_MAX_PC_RETRIES)
110 * Some drives (for example, Seagate STT3401A Travan) require a very long
111 * timeout, because they don't return an interrupt or clear their busy bit
112 * until after the command completes (even retension commands).
114 #define IDETAPE_WAIT_CMD (900*HZ)
117 * The following parameter is used to select the point in the internal
118 * tape fifo in which we will start to refill the buffer. Decreasing
119 * the following parameter will improve the system's latency and
120 * interactive response, while using a high value might improve system
123 #define IDETAPE_FIFO_THRESHOLD 2
126 * DSC polling parameters.
128 * Polling for DSC (a single bit in the status register) is a very
129 * important function in ide-tape. There are two cases in which we
132 * 1. Before a read/write packet command, to ensure that we
133 * can transfer data from/to the tape's data buffers, without
134 * causing an actual media access. In case the tape is not
135 * ready yet, we take out our request from the device
136 * request queue, so that ide.c will service requests from
137 * the other device on the same interface meanwhile.
139 * 2. After the successful initialization of a "media access
140 * packet command", which is a command which can take a long
141 * time to complete (it can be several seconds or even an hour).
143 * Again, we postpone our request in the middle to free the bus
144 * for the other device. The polling frequency here should be
145 * lower than the read/write frequency since those media access
146 * commands are slow. We start from a "fast" frequency -
147 * IDETAPE_DSC_MA_FAST (one second), and if we don't receive DSC
148 * after IDETAPE_DSC_MA_THRESHOLD (5 minutes), we switch it to a
149 * lower frequency - IDETAPE_DSC_MA_SLOW (1 minute).
151 * We also set a timeout for the timer, in case something goes wrong.
152 * The timeout should be longer then the maximum execution time of a
159 #define IDETAPE_DSC_RW_MIN 5*HZ/100 /* 50 msec */
160 #define IDETAPE_DSC_RW_MAX 40*HZ/100 /* 400 msec */
161 #define IDETAPE_DSC_RW_TIMEOUT 2*60*HZ /* 2 minutes */
162 #define IDETAPE_DSC_MA_FAST 2*HZ /* 2 seconds */
163 #define IDETAPE_DSC_MA_THRESHOLD 5*60*HZ /* 5 minutes */
164 #define IDETAPE_DSC_MA_SLOW 30*HZ /* 30 seconds */
165 #define IDETAPE_DSC_MA_TIMEOUT 2*60*60*HZ /* 2 hours */
167 /*************************** End of tunable parameters ***********************/
170 * Read/Write error simulation
172 #define SIMULATE_ERRORS 0
175 * For general magnetic tape device compatibility.
178 idetape_direction_none,
179 idetape_direction_read,
180 idetape_direction_write
181 } idetape_chrdev_direction_t;
186 struct idetape_bh *b_reqnext;
191 * Our view of a packet command.
193 typedef struct idetape_packet_command_s {
194 u8 c[12]; /* Actual packet bytes */
195 int retries; /* On each retry, we increment retries */
196 int error; /* Error code */
197 int request_transfer; /* Bytes to transfer */
198 int actually_transferred; /* Bytes actually transferred */
199 int buffer_size; /* Size of our data buffer */
200 struct idetape_bh *bh;
203 u8 *buffer; /* Data buffer */
204 u8 *current_position; /* Pointer into the above buffer */
205 ide_startstop_t (*callback) (ide_drive_t *); /* Called when this packet command is completed */
206 u8 pc_buffer[IDETAPE_PC_BUFFER_SIZE]; /* Temporary buffer */
207 unsigned long flags; /* Status/Action bit flags: long for set_bit */
211 * Packet command flag bits.
213 /* Set when an error is considered normal - We won't retry */
215 /* 1 When polling for DSC on a media access command */
216 #define PC_WAIT_FOR_DSC 1
217 /* 1 when we prefer to use DMA if possible */
218 #define PC_DMA_RECOMMENDED 2
219 /* 1 while DMA in progress */
220 #define PC_DMA_IN_PROGRESS 3
221 /* 1 when encountered problem during DMA */
222 #define PC_DMA_ERROR 4
229 typedef struct idetape_stage_s {
230 struct request rq; /* The corresponding request */
231 struct idetape_bh *bh; /* The data buffers */
232 struct idetape_stage_s *next; /* Pointer to the next stage */
236 * Most of our global data which we need to save even as we leave the
237 * driver due to an interrupt or a timer event is stored in a variable
238 * of type idetape_tape_t, defined below.
240 typedef struct ide_tape_obj {
242 ide_driver_t *driver;
243 struct gendisk *disk;
247 * Since a typical character device operation requires more
248 * than one packet command, we provide here enough memory
249 * for the maximum of interconnected packet commands.
250 * The packet commands are stored in the circular array pc_stack.
251 * pc_stack_index points to the last used entry, and warps around
252 * to the start when we get to the last array entry.
254 * pc points to the current processed packet command.
256 * failed_pc points to the last failed packet command, or contains
257 * NULL if we do not need to retry any packet command. This is
258 * required since an additional packet command is needed before the
259 * retry, to get detailed information on what went wrong.
261 /* Current packet command */
263 /* Last failed packet command */
264 idetape_pc_t *failed_pc;
265 /* Packet command stack */
266 idetape_pc_t pc_stack[IDETAPE_PC_STACK];
267 /* Next free packet command storage space */
269 struct request rq_stack[IDETAPE_PC_STACK];
270 /* We implement a circular array */
274 * DSC polling variables.
276 * While polling for DSC we use postponed_rq to postpone the
277 * current request so that ide.c will be able to service
278 * pending requests on the other device. Note that at most
279 * we will have only one DSC (usually data transfer) request
280 * in the device request queue. Additional requests can be
281 * queued in our internal pipeline, but they will be visible
282 * to ide.c only one at a time.
284 struct request *postponed_rq;
285 /* The time in which we started polling for DSC */
286 unsigned long dsc_polling_start;
287 /* Timer used to poll for dsc */
288 struct timer_list dsc_timer;
289 /* Read/Write dsc polling frequency */
290 unsigned long best_dsc_rw_frequency;
291 /* The current polling frequency */
292 unsigned long dsc_polling_frequency;
293 /* Maximum waiting time */
294 unsigned long dsc_timeout;
297 * Read position information
301 unsigned int first_frame_position;
302 unsigned int last_frame_position;
303 unsigned int blocks_in_buffer;
306 * Last error information
308 u8 sense_key, asc, ascq;
311 * Character device operation
316 /* Current character device data transfer direction */
317 idetape_chrdev_direction_t chrdev_direction;
322 /* Usually 512 or 1024 bytes */
323 unsigned short tape_block_size;
326 /* Copy of the tape's Capabilities and Mechanical Page */
330 * Active data transfer request parameters.
332 * At most, there is only one ide-tape originated data transfer
333 * request in the device request queue. This allows ide.c to
334 * easily service requests from the other device when we
335 * postpone our active request. In the pipelined operation
336 * mode, we use our internal pipeline structure to hold
337 * more data requests.
339 * The data buffer size is chosen based on the tape's
342 /* Pointer to the request which is waiting in the device request queue */
343 struct request *active_data_request;
344 /* Data buffer size (chosen based on the tape's recommendation */
346 idetape_stage_t *merge_stage;
347 int merge_stage_size;
348 struct idetape_bh *bh;
353 * Pipeline parameters.
355 * To accomplish non-pipelined mode, we simply set the following
356 * variables to zero (or NULL, where appropriate).
358 /* Number of currently used stages */
360 /* Number of pending stages */
361 int nr_pending_stages;
362 /* We will not allocate more than this number of stages */
363 int max_stages, min_pipeline, max_pipeline;
364 /* The first stage which will be removed from the pipeline */
365 idetape_stage_t *first_stage;
366 /* The currently active stage */
367 idetape_stage_t *active_stage;
368 /* Will be serviced after the currently active request */
369 idetape_stage_t *next_stage;
370 /* New requests will be added to the pipeline here */
371 idetape_stage_t *last_stage;
372 /* Optional free stage which we can use */
373 idetape_stage_t *cache_stage;
375 /* Wasted space in each stage */
378 /* Status/Action flags: long for set_bit */
380 /* protects the ide-tape queue */
384 * Measures average tape speed
386 unsigned long avg_time;
392 char firmware_revision[6];
393 int firmware_revision_num;
395 /* the door is currently locked */
397 /* the tape hardware is write protected */
399 /* the tape is write protected (hardware or opened as read-only) */
403 * Limit the number of times a request can
404 * be postponed, to avoid an infinite postpone
407 /* request postpone count limit */
411 * Measures number of frames:
413 * 1. written/read to/from the driver pipeline (pipeline_head).
414 * 2. written/read to/from the tape buffers (idetape_bh).
415 * 3. written/read by the tape to/from the media (tape_head).
423 * Speed control at the tape buffers input/output
425 unsigned long insert_time;
428 int max_insert_speed;
429 int measure_insert_time;
432 * Measure tape still time, in milliseconds
434 unsigned long tape_still_time_begin;
438 * Speed regulation negative feedback loop
441 int pipeline_head_speed;
442 int controlled_pipeline_head_speed;
443 int uncontrolled_pipeline_head_speed;
444 int controlled_last_pipeline_head;
445 int uncontrolled_last_pipeline_head;
446 unsigned long uncontrolled_pipeline_head_time;
447 unsigned long controlled_pipeline_head_time;
448 int controlled_previous_pipeline_head;
449 int uncontrolled_previous_pipeline_head;
450 unsigned long controlled_previous_head_time;
451 unsigned long uncontrolled_previous_head_time;
452 int restart_speed_control_req;
455 * Debug_level determines amount of debugging output;
456 * can be changed using /proc/ide/hdx/settings
457 * 0 : almost no debugging output
458 * 1 : 0+output errors only
459 * 2 : 1+output all sensekey/asc
460 * 3 : 2+follow all chrdev related procedures
461 * 4 : 3+follow all procedures
462 * 5 : 4+include pc_stack rq_stack info
463 * 6 : 5+USE_COUNT updates
468 static DEFINE_MUTEX(idetape_ref_mutex);
470 static struct class *idetape_sysfs_class;
472 #define to_ide_tape(obj) container_of(obj, struct ide_tape_obj, kref)
474 #define ide_tape_g(disk) \
475 container_of((disk)->private_data, struct ide_tape_obj, driver)
477 static struct ide_tape_obj *ide_tape_get(struct gendisk *disk)
479 struct ide_tape_obj *tape = NULL;
481 mutex_lock(&idetape_ref_mutex);
482 tape = ide_tape_g(disk);
484 kref_get(&tape->kref);
485 mutex_unlock(&idetape_ref_mutex);
489 static void ide_tape_release(struct kref *);
491 static void ide_tape_put(struct ide_tape_obj *tape)
493 mutex_lock(&idetape_ref_mutex);
494 kref_put(&tape->kref, ide_tape_release);
495 mutex_unlock(&idetape_ref_mutex);
501 #define DOOR_UNLOCKED 0
502 #define DOOR_LOCKED 1
503 #define DOOR_EXPLICITLY_LOCKED 2
506 * Tape flag bits values.
508 #define IDETAPE_IGNORE_DSC 0
509 #define IDETAPE_ADDRESS_VALID 1 /* 0 When the tape position is unknown */
510 #define IDETAPE_BUSY 2 /* Device already opened */
511 #define IDETAPE_PIPELINE_ERROR 3 /* Error detected in a pipeline stage */
512 #define IDETAPE_DETECT_BS 4 /* Attempt to auto-detect the current user block size */
513 #define IDETAPE_FILEMARK 5 /* Currently on a filemark */
514 #define IDETAPE_DRQ_INTERRUPT 6 /* DRQ interrupt device */
515 #define IDETAPE_READ_ERROR 7
516 #define IDETAPE_PIPELINE_ACTIVE 8 /* pipeline active */
517 /* 0 = no tape is loaded, so we don't rewind after ejecting */
518 #define IDETAPE_MEDIUM_PRESENT 9
521 * Some defines for the READ BUFFER command
523 #define IDETAPE_RETRIEVE_FAULTY_BLOCK 6
526 * Some defines for the SPACE command
528 #define IDETAPE_SPACE_OVER_FILEMARK 1
529 #define IDETAPE_SPACE_TO_EOD 3
532 * Some defines for the LOAD UNLOAD command
534 #define IDETAPE_LU_LOAD_MASK 1
535 #define IDETAPE_LU_RETENSION_MASK 2
536 #define IDETAPE_LU_EOT_MASK 4
539 * Special requests for our block device strategy routine.
541 * In order to service a character device command, we add special
542 * requests to the tail of our block device request queue and wait
543 * for their completion.
547 REQ_IDETAPE_PC1 = (1 << 0), /* packet command (first stage) */
548 REQ_IDETAPE_PC2 = (1 << 1), /* packet command (second stage) */
549 REQ_IDETAPE_READ = (1 << 2),
550 REQ_IDETAPE_WRITE = (1 << 3),
551 REQ_IDETAPE_READ_BUFFER = (1 << 4),
555 * Error codes which are returned in rq->errors to the higher part
558 #define IDETAPE_ERROR_GENERAL 101
559 #define IDETAPE_ERROR_FILEMARK 102
560 #define IDETAPE_ERROR_EOD 103
563 * The following is used to format the general configuration word of
564 * the ATAPI IDENTIFY DEVICE command.
566 struct idetape_id_gcw {
567 unsigned packet_size :2; /* Packet Size */
568 unsigned reserved234 :3; /* Reserved */
569 unsigned drq_type :2; /* Command packet DRQ type */
570 unsigned removable :1; /* Removable media */
571 unsigned device_type :5; /* Device type */
572 unsigned reserved13 :1; /* Reserved */
573 unsigned protocol :2; /* Protocol type */
577 * READ POSITION packet command - Data Format (From Table 6-57)
580 unsigned reserved0_10 :2; /* Reserved */
581 unsigned bpu :1; /* Block Position Unknown */
582 unsigned reserved0_543 :3; /* Reserved */
583 unsigned eop :1; /* End Of Partition */
584 unsigned bop :1; /* Beginning Of Partition */
585 u8 partition; /* Partition Number */
586 u8 reserved2, reserved3; /* Reserved */
587 u32 first_block; /* First Block Location */
588 u32 last_block; /* Last Block Location (Optional) */
589 u8 reserved12; /* Reserved */
590 u8 blocks_in_buffer[3]; /* Blocks In Buffer - (Optional) */
591 u32 bytes_in_buffer; /* Bytes In Buffer (Optional) */
592 } idetape_read_position_result_t;
595 * Follows structures which are related to the SELECT SENSE / MODE SENSE
596 * packet commands. Those packet commands are still not supported
599 #define IDETAPE_BLOCK_DESCRIPTOR 0
600 #define IDETAPE_CAPABILITIES_PAGE 0x2a
601 #define IDETAPE_PARAMTR_PAGE 0x2b /* Onstream DI-x0 only */
602 #define IDETAPE_BLOCK_SIZE_PAGE 0x30
603 #define IDETAPE_BUFFER_FILLING_PAGE 0x33
606 * Run time configurable parameters.
609 int dsc_rw_frequency;
610 int dsc_media_access_frequency;
615 * The variables below are used for the character device interface.
616 * Additional state variables are defined in our ide_drive_t structure.
618 static struct ide_tape_obj * idetape_devs[MAX_HWIFS * MAX_DRIVES];
620 #define ide_tape_f(file) ((file)->private_data)
622 static struct ide_tape_obj *ide_tape_chrdev_get(unsigned int i)
624 struct ide_tape_obj *tape = NULL;
626 mutex_lock(&idetape_ref_mutex);
627 tape = idetape_devs[i];
629 kref_get(&tape->kref);
630 mutex_unlock(&idetape_ref_mutex);
635 * Function declarations
638 static int idetape_chrdev_release (struct inode *inode, struct file *filp);
639 static void idetape_write_release (ide_drive_t *drive, unsigned int minor);
642 * Too bad. The drive wants to send us data which we are not ready to accept.
643 * Just throw it away.
645 static void idetape_discard_data (ide_drive_t *drive, unsigned int bcount)
648 (void) HWIF(drive)->INB(IDE_DATA_REG);
651 static void idetape_input_buffers (ide_drive_t *drive, idetape_pc_t *pc, unsigned int bcount)
653 struct idetape_bh *bh = pc->bh;
658 printk(KERN_ERR "ide-tape: bh == NULL in "
659 "idetape_input_buffers\n");
660 idetape_discard_data(drive, bcount);
663 count = min((unsigned int)(bh->b_size - atomic_read(&bh->b_count)), bcount);
664 HWIF(drive)->atapi_input_bytes(drive, bh->b_data + atomic_read(&bh->b_count), count);
666 atomic_add(count, &bh->b_count);
667 if (atomic_read(&bh->b_count) == bh->b_size) {
670 atomic_set(&bh->b_count, 0);
676 static void idetape_output_buffers (ide_drive_t *drive, idetape_pc_t *pc, unsigned int bcount)
678 struct idetape_bh *bh = pc->bh;
683 printk(KERN_ERR "ide-tape: bh == NULL in "
684 "idetape_output_buffers\n");
687 count = min((unsigned int)pc->b_count, (unsigned int)bcount);
688 HWIF(drive)->atapi_output_bytes(drive, pc->b_data, count);
691 pc->b_count -= count;
693 pc->bh = bh = bh->b_reqnext;
695 pc->b_data = bh->b_data;
696 pc->b_count = atomic_read(&bh->b_count);
702 static void idetape_update_buffers (idetape_pc_t *pc)
704 struct idetape_bh *bh = pc->bh;
706 unsigned int bcount = pc->actually_transferred;
708 if (test_bit(PC_WRITING, &pc->flags))
712 printk(KERN_ERR "ide-tape: bh == NULL in "
713 "idetape_update_buffers\n");
716 count = min((unsigned int)bh->b_size, (unsigned int)bcount);
717 atomic_set(&bh->b_count, count);
718 if (atomic_read(&bh->b_count) == bh->b_size)
726 * idetape_next_pc_storage returns a pointer to a place in which we can
727 * safely store a packet command, even though we intend to leave the
728 * driver. A storage space for a maximum of IDETAPE_PC_STACK packet
729 * commands is allocated at initialization time.
731 static idetape_pc_t *idetape_next_pc_storage (ide_drive_t *drive)
733 idetape_tape_t *tape = drive->driver_data;
735 #if IDETAPE_DEBUG_LOG
736 if (tape->debug_level >= 5)
737 printk(KERN_INFO "ide-tape: pc_stack_index=%d\n",
738 tape->pc_stack_index);
739 #endif /* IDETAPE_DEBUG_LOG */
740 if (tape->pc_stack_index == IDETAPE_PC_STACK)
741 tape->pc_stack_index=0;
742 return (&tape->pc_stack[tape->pc_stack_index++]);
746 * idetape_next_rq_storage is used along with idetape_next_pc_storage.
747 * Since we queue packet commands in the request queue, we need to
748 * allocate a request, along with the allocation of a packet command.
751 /**************************************************************
753 * This should get fixed to use kmalloc(.., GFP_ATOMIC) *
754 * followed later on by kfree(). -ml *
756 **************************************************************/
758 static struct request *idetape_next_rq_storage (ide_drive_t *drive)
760 idetape_tape_t *tape = drive->driver_data;
762 #if IDETAPE_DEBUG_LOG
763 if (tape->debug_level >= 5)
764 printk(KERN_INFO "ide-tape: rq_stack_index=%d\n",
765 tape->rq_stack_index);
766 #endif /* IDETAPE_DEBUG_LOG */
767 if (tape->rq_stack_index == IDETAPE_PC_STACK)
768 tape->rq_stack_index=0;
769 return (&tape->rq_stack[tape->rq_stack_index++]);
773 * idetape_init_pc initializes a packet command.
775 static void idetape_init_pc (idetape_pc_t *pc)
777 memset(pc->c, 0, 12);
780 pc->request_transfer = 0;
781 pc->buffer = pc->pc_buffer;
782 pc->buffer_size = IDETAPE_PC_BUFFER_SIZE;
788 * called on each failed packet command retry to analyze the request sense. We
789 * currently do not utilize this information.
791 static void idetape_analyze_error(ide_drive_t *drive, u8 *sense)
793 idetape_tape_t *tape = drive->driver_data;
794 idetape_pc_t *pc = tape->failed_pc;
796 tape->sense_key = sense[2] & 0xF;
797 tape->asc = sense[12];
798 tape->ascq = sense[13];
799 #if IDETAPE_DEBUG_LOG
801 * Without debugging, we only log an error if we decided to give up
804 if (tape->debug_level >= 1)
805 printk(KERN_INFO "ide-tape: pc = %x, sense key = %x, "
806 "asc = %x, ascq = %x\n",
807 pc->c[0], tape->sense_key,
808 tape->asc, tape->ascq);
809 #endif /* IDETAPE_DEBUG_LOG */
811 /* Correct pc->actually_transferred by asking the tape. */
812 if (test_bit(PC_DMA_ERROR, &pc->flags)) {
813 pc->actually_transferred = pc->request_transfer -
814 tape->tape_block_size *
815 ntohl(get_unaligned((u32 *)&sense[3]));
816 idetape_update_buffers(pc);
820 * If error was the result of a zero-length read or write command,
821 * with sense key=5, asc=0x22, ascq=0, let it slide. Some drives
822 * (i.e. Seagate STT3401A Travan) don't support 0-length read/writes.
824 if ((pc->c[0] == READ_6 || pc->c[0] == WRITE_6)
826 && pc->c[4] == 0 && pc->c[3] == 0 && pc->c[2] == 0) {
827 if (tape->sense_key == 5) {
828 /* don't report an error, everything's ok */
830 /* don't retry read/write */
831 set_bit(PC_ABORT, &pc->flags);
834 if (pc->c[0] == READ_6 && (sense[2] & 0x80)) {
835 pc->error = IDETAPE_ERROR_FILEMARK;
836 set_bit(PC_ABORT, &pc->flags);
838 if (pc->c[0] == WRITE_6) {
839 if ((sense[2] & 0x40) || (tape->sense_key == 0xd
840 && tape->asc == 0x0 && tape->ascq == 0x2)) {
841 pc->error = IDETAPE_ERROR_EOD;
842 set_bit(PC_ABORT, &pc->flags);
845 if (pc->c[0] == READ_6 || pc->c[0] == WRITE_6) {
846 if (tape->sense_key == 8) {
847 pc->error = IDETAPE_ERROR_EOD;
848 set_bit(PC_ABORT, &pc->flags);
850 if (!test_bit(PC_ABORT, &pc->flags) &&
851 pc->actually_transferred)
852 pc->retries = IDETAPE_MAX_PC_RETRIES + 1;
857 * idetape_active_next_stage will declare the next stage as "active".
859 static void idetape_active_next_stage (ide_drive_t *drive)
861 idetape_tape_t *tape = drive->driver_data;
862 idetape_stage_t *stage = tape->next_stage;
863 struct request *rq = &stage->rq;
865 #if IDETAPE_DEBUG_LOG
866 if (tape->debug_level >= 4)
867 printk(KERN_INFO "ide-tape: Reached idetape_active_next_stage\n");
868 #endif /* IDETAPE_DEBUG_LOG */
870 printk(KERN_ERR "ide-tape: bug: Trying to activate a non existing stage\n");
874 rq->rq_disk = tape->disk;
876 rq->special = (void *)stage->bh;
877 tape->active_data_request = rq;
878 tape->active_stage = stage;
879 tape->next_stage = stage->next;
883 * idetape_increase_max_pipeline_stages is a part of the feedback
884 * loop which tries to find the optimum number of stages. In the
885 * feedback loop, we are starting from a minimum maximum number of
886 * stages, and if we sense that the pipeline is empty, we try to
887 * increase it, until we reach the user compile time memory limit.
889 static void idetape_increase_max_pipeline_stages (ide_drive_t *drive)
891 idetape_tape_t *tape = drive->driver_data;
892 int increase = (tape->max_pipeline - tape->min_pipeline) / 10;
894 #if IDETAPE_DEBUG_LOG
895 if (tape->debug_level >= 4)
896 printk (KERN_INFO "ide-tape: Reached idetape_increase_max_pipeline_stages\n");
897 #endif /* IDETAPE_DEBUG_LOG */
899 tape->max_stages += max(increase, 1);
900 tape->max_stages = max(tape->max_stages, tape->min_pipeline);
901 tape->max_stages = min(tape->max_stages, tape->max_pipeline);
905 * idetape_kfree_stage calls kfree to completely free a stage, along with
906 * its related buffers.
908 static void __idetape_kfree_stage (idetape_stage_t *stage)
910 struct idetape_bh *prev_bh, *bh = stage->bh;
914 if (bh->b_data != NULL) {
915 size = (int) bh->b_size;
917 free_page((unsigned long) bh->b_data);
919 bh->b_data += PAGE_SIZE;
929 static void idetape_kfree_stage (idetape_tape_t *tape, idetape_stage_t *stage)
931 __idetape_kfree_stage(stage);
935 * idetape_remove_stage_head removes tape->first_stage from the pipeline.
936 * The caller should avoid race conditions.
938 static void idetape_remove_stage_head (ide_drive_t *drive)
940 idetape_tape_t *tape = drive->driver_data;
941 idetape_stage_t *stage;
943 #if IDETAPE_DEBUG_LOG
944 if (tape->debug_level >= 4)
945 printk(KERN_INFO "ide-tape: Reached idetape_remove_stage_head\n");
946 #endif /* IDETAPE_DEBUG_LOG */
947 if (tape->first_stage == NULL) {
948 printk(KERN_ERR "ide-tape: bug: tape->first_stage is NULL\n");
951 if (tape->active_stage == tape->first_stage) {
952 printk(KERN_ERR "ide-tape: bug: Trying to free our active pipeline stage\n");
955 stage = tape->first_stage;
956 tape->first_stage = stage->next;
957 idetape_kfree_stage(tape, stage);
959 if (tape->first_stage == NULL) {
960 tape->last_stage = NULL;
961 if (tape->next_stage != NULL)
962 printk(KERN_ERR "ide-tape: bug: tape->next_stage != NULL\n");
964 printk(KERN_ERR "ide-tape: bug: nr_stages should be 0 now\n");
969 * This will free all the pipeline stages starting from new_last_stage->next
970 * to the end of the list, and point tape->last_stage to new_last_stage.
972 static void idetape_abort_pipeline(ide_drive_t *drive,
973 idetape_stage_t *new_last_stage)
975 idetape_tape_t *tape = drive->driver_data;
976 idetape_stage_t *stage = new_last_stage->next;
977 idetape_stage_t *nstage;
979 #if IDETAPE_DEBUG_LOG
980 if (tape->debug_level >= 4)
981 printk(KERN_INFO "ide-tape: %s: idetape_abort_pipeline called\n", tape->name);
984 nstage = stage->next;
985 idetape_kfree_stage(tape, stage);
987 --tape->nr_pending_stages;
991 new_last_stage->next = NULL;
992 tape->last_stage = new_last_stage;
993 tape->next_stage = NULL;
997 * idetape_end_request is used to finish servicing a request, and to
998 * insert a pending pipeline request into the main device queue.
1000 static int idetape_end_request(ide_drive_t *drive, int uptodate, int nr_sects)
1002 struct request *rq = HWGROUP(drive)->rq;
1003 idetape_tape_t *tape = drive->driver_data;
1004 unsigned long flags;
1006 int remove_stage = 0;
1007 idetape_stage_t *active_stage;
1009 #if IDETAPE_DEBUG_LOG
1010 if (tape->debug_level >= 4)
1011 printk(KERN_INFO "ide-tape: Reached idetape_end_request\n");
1012 #endif /* IDETAPE_DEBUG_LOG */
1015 case 0: error = IDETAPE_ERROR_GENERAL; break;
1016 case 1: error = 0; break;
1017 default: error = uptodate;
1021 tape->failed_pc = NULL;
1023 if (!blk_special_request(rq)) {
1024 ide_end_request(drive, uptodate, nr_sects);
1028 spin_lock_irqsave(&tape->spinlock, flags);
1030 /* The request was a pipelined data transfer request */
1031 if (tape->active_data_request == rq) {
1032 active_stage = tape->active_stage;
1033 tape->active_stage = NULL;
1034 tape->active_data_request = NULL;
1035 tape->nr_pending_stages--;
1036 if (rq->cmd[0] & REQ_IDETAPE_WRITE) {
1039 set_bit(IDETAPE_PIPELINE_ERROR, &tape->flags);
1040 if (error == IDETAPE_ERROR_EOD)
1041 idetape_abort_pipeline(drive, active_stage);
1043 } else if (rq->cmd[0] & REQ_IDETAPE_READ) {
1044 if (error == IDETAPE_ERROR_EOD) {
1045 set_bit(IDETAPE_PIPELINE_ERROR, &tape->flags);
1046 idetape_abort_pipeline(drive, active_stage);
1049 if (tape->next_stage != NULL) {
1050 idetape_active_next_stage(drive);
1053 * Insert the next request into the request queue.
1055 (void) ide_do_drive_cmd(drive, tape->active_data_request, ide_end);
1056 } else if (!error) {
1057 idetape_increase_max_pipeline_stages(drive);
1060 ide_end_drive_cmd(drive, 0, 0);
1061 // blkdev_dequeue_request(rq);
1062 // drive->rq = NULL;
1063 // end_that_request_last(rq);
1066 idetape_remove_stage_head(drive);
1067 if (tape->active_data_request == NULL)
1068 clear_bit(IDETAPE_PIPELINE_ACTIVE, &tape->flags);
1069 spin_unlock_irqrestore(&tape->spinlock, flags);
1073 static ide_startstop_t idetape_request_sense_callback (ide_drive_t *drive)
1075 idetape_tape_t *tape = drive->driver_data;
1077 #if IDETAPE_DEBUG_LOG
1078 if (tape->debug_level >= 4)
1079 printk(KERN_INFO "ide-tape: Reached idetape_request_sense_callback\n");
1080 #endif /* IDETAPE_DEBUG_LOG */
1081 if (!tape->pc->error) {
1082 idetape_analyze_error(drive, tape->pc->buffer);
1083 idetape_end_request(drive, 1, 0);
1085 printk(KERN_ERR "ide-tape: Error in REQUEST SENSE itself - Aborting request!\n");
1086 idetape_end_request(drive, 0, 0);
1091 static void idetape_create_request_sense_cmd (idetape_pc_t *pc)
1093 idetape_init_pc(pc);
1094 pc->c[0] = REQUEST_SENSE;
1096 pc->request_transfer = 20;
1097 pc->callback = &idetape_request_sense_callback;
1100 static void idetape_init_rq(struct request *rq, u8 cmd)
1102 memset(rq, 0, sizeof(*rq));
1103 rq->cmd_type = REQ_TYPE_SPECIAL;
1108 * idetape_queue_pc_head generates a new packet command request in front
1109 * of the request queue, before the current request, so that it will be
1110 * processed immediately, on the next pass through the driver.
1112 * idetape_queue_pc_head is called from the request handling part of
1113 * the driver (the "bottom" part). Safe storage for the request should
1114 * be allocated with idetape_next_pc_storage and idetape_next_rq_storage
1115 * before calling idetape_queue_pc_head.
1117 * Memory for those requests is pre-allocated at initialization time, and
1118 * is limited to IDETAPE_PC_STACK requests. We assume that we have enough
1119 * space for the maximum possible number of inter-dependent packet commands.
1121 * The higher level of the driver - The ioctl handler and the character
1122 * device handling functions should queue request to the lower level part
1123 * and wait for their completion using idetape_queue_pc_tail or
1124 * idetape_queue_rw_tail.
1126 static void idetape_queue_pc_head (ide_drive_t *drive, idetape_pc_t *pc,struct request *rq)
1128 struct ide_tape_obj *tape = drive->driver_data;
1130 idetape_init_rq(rq, REQ_IDETAPE_PC1);
1131 rq->buffer = (char *) pc;
1132 rq->rq_disk = tape->disk;
1133 (void) ide_do_drive_cmd(drive, rq, ide_preempt);
1137 * idetape_retry_pc is called when an error was detected during the
1138 * last packet command. We queue a request sense packet command in
1139 * the head of the request list.
1141 static ide_startstop_t idetape_retry_pc (ide_drive_t *drive)
1143 idetape_tape_t *tape = drive->driver_data;
1147 (void)drive->hwif->INB(IDE_ERROR_REG);
1148 pc = idetape_next_pc_storage(drive);
1149 rq = idetape_next_rq_storage(drive);
1150 idetape_create_request_sense_cmd(pc);
1151 set_bit(IDETAPE_IGNORE_DSC, &tape->flags);
1152 idetape_queue_pc_head(drive, pc, rq);
1157 * idetape_postpone_request postpones the current request so that
1158 * ide.c will be able to service requests from another device on
1159 * the same hwgroup while we are polling for DSC.
1161 static void idetape_postpone_request (ide_drive_t *drive)
1163 idetape_tape_t *tape = drive->driver_data;
1165 #if IDETAPE_DEBUG_LOG
1166 if (tape->debug_level >= 4)
1167 printk(KERN_INFO "ide-tape: idetape_postpone_request\n");
1169 tape->postponed_rq = HWGROUP(drive)->rq;
1170 ide_stall_queue(drive, tape->dsc_polling_frequency);
1174 * idetape_pc_intr is the usual interrupt handler which will be called
1175 * during a packet command. We will transfer some of the data (as
1176 * requested by the drive) and will re-point interrupt handler to us.
1177 * When data transfer is finished, we will act according to the
1178 * algorithm described before idetape_issue_packet_command.
1181 static ide_startstop_t idetape_pc_intr (ide_drive_t *drive)
1183 ide_hwif_t *hwif = drive->hwif;
1184 idetape_tape_t *tape = drive->driver_data;
1185 idetape_pc_t *pc = tape->pc;
1188 static int error_sim_count = 0;
1193 #if IDETAPE_DEBUG_LOG
1194 if (tape->debug_level >= 4)
1195 printk(KERN_INFO "ide-tape: Reached idetape_pc_intr "
1196 "interrupt handler\n");
1197 #endif /* IDETAPE_DEBUG_LOG */
1199 /* Clear the interrupt */
1200 stat = hwif->INB(IDE_STATUS_REG);
1202 if (test_bit(PC_DMA_IN_PROGRESS, &pc->flags)) {
1203 if (hwif->ide_dma_end(drive) || (stat & ERR_STAT)) {
1205 * A DMA error is sometimes expected. For example,
1206 * if the tape is crossing a filemark during a
1207 * READ command, it will issue an irq and position
1208 * itself before the filemark, so that only a partial
1209 * data transfer will occur (which causes the DMA
1210 * error). In that case, we will later ask the tape
1211 * how much bytes of the original request were
1212 * actually transferred (we can't receive that
1213 * information from the DMA engine on most chipsets).
1217 * On the contrary, a DMA error is never expected;
1218 * it usually indicates a hardware error or abort.
1219 * If the tape crosses a filemark during a READ
1220 * command, it will issue an irq and position itself
1221 * after the filemark (not before). Only a partial
1222 * data transfer will occur, but no DMA error.
1225 set_bit(PC_DMA_ERROR, &pc->flags);
1227 pc->actually_transferred = pc->request_transfer;
1228 idetape_update_buffers(pc);
1230 #if IDETAPE_DEBUG_LOG
1231 if (tape->debug_level >= 4)
1232 printk(KERN_INFO "ide-tape: DMA finished\n");
1233 #endif /* IDETAPE_DEBUG_LOG */
1236 /* No more interrupts */
1237 if ((stat & DRQ_STAT) == 0) {
1238 #if IDETAPE_DEBUG_LOG
1239 if (tape->debug_level >= 2)
1240 printk(KERN_INFO "ide-tape: Packet command completed, %d bytes transferred\n", pc->actually_transferred);
1241 #endif /* IDETAPE_DEBUG_LOG */
1242 clear_bit(PC_DMA_IN_PROGRESS, &pc->flags);
1247 if ((pc->c[0] == WRITE_6 || pc->c[0] == READ_6) &&
1248 (++error_sim_count % 100) == 0) {
1249 printk(KERN_INFO "ide-tape: %s: simulating error\n",
1254 if ((stat & ERR_STAT) && pc->c[0] == REQUEST_SENSE)
1256 if ((stat & ERR_STAT) || test_bit(PC_DMA_ERROR, &pc->flags)) {
1257 /* Error detected */
1258 #if IDETAPE_DEBUG_LOG
1259 if (tape->debug_level >= 1)
1260 printk(KERN_INFO "ide-tape: %s: I/O error\n",
1262 #endif /* IDETAPE_DEBUG_LOG */
1263 if (pc->c[0] == REQUEST_SENSE) {
1264 printk(KERN_ERR "ide-tape: I/O error in request sense command\n");
1265 return ide_do_reset(drive);
1267 #if IDETAPE_DEBUG_LOG
1268 if (tape->debug_level >= 1)
1269 printk(KERN_INFO "ide-tape: [cmd %x]: check condition\n", pc->c[0]);
1271 /* Retry operation */
1272 return idetape_retry_pc(drive);
1275 if (test_bit(PC_WAIT_FOR_DSC, &pc->flags) &&
1276 (stat & SEEK_STAT) == 0) {
1277 /* Media access command */
1278 tape->dsc_polling_start = jiffies;
1279 tape->dsc_polling_frequency = IDETAPE_DSC_MA_FAST;
1280 tape->dsc_timeout = jiffies + IDETAPE_DSC_MA_TIMEOUT;
1281 /* Allow ide.c to handle other requests */
1282 idetape_postpone_request(drive);
1285 if (tape->failed_pc == pc)
1286 tape->failed_pc = NULL;
1287 /* Command finished - Call the callback function */
1288 return pc->callback(drive);
1290 if (test_and_clear_bit(PC_DMA_IN_PROGRESS, &pc->flags)) {
1291 printk(KERN_ERR "ide-tape: The tape wants to issue more "
1292 "interrupts in DMA mode\n");
1293 printk(KERN_ERR "ide-tape: DMA disabled, reverting to PIO\n");
1295 return ide_do_reset(drive);
1297 /* Get the number of bytes to transfer on this interrupt. */
1298 bcount = (hwif->INB(IDE_BCOUNTH_REG) << 8) |
1299 hwif->INB(IDE_BCOUNTL_REG);
1301 ireason = hwif->INB(IDE_IREASON_REG);
1304 printk(KERN_ERR "ide-tape: CoD != 0 in idetape_pc_intr\n");
1305 return ide_do_reset(drive);
1307 if (((ireason & IO) == IO) == test_bit(PC_WRITING, &pc->flags)) {
1308 /* Hopefully, we will never get here */
1309 printk(KERN_ERR "ide-tape: We wanted to %s, ",
1310 (ireason & IO) ? "Write" : "Read");
1311 printk(KERN_ERR "ide-tape: but the tape wants us to %s !\n",
1312 (ireason & IO) ? "Read" : "Write");
1313 return ide_do_reset(drive);
1315 if (!test_bit(PC_WRITING, &pc->flags)) {
1316 /* Reading - Check that we have enough space */
1317 temp = pc->actually_transferred + bcount;
1318 if (temp > pc->request_transfer) {
1319 if (temp > pc->buffer_size) {
1320 printk(KERN_ERR "ide-tape: The tape wants to send us more data than expected - discarding data\n");
1321 idetape_discard_data(drive, bcount);
1322 ide_set_handler(drive, &idetape_pc_intr, IDETAPE_WAIT_CMD, NULL);
1325 #if IDETAPE_DEBUG_LOG
1326 if (tape->debug_level >= 2)
1327 printk(KERN_NOTICE "ide-tape: The tape wants to send us more data than expected - allowing transfer\n");
1328 #endif /* IDETAPE_DEBUG_LOG */
1331 if (test_bit(PC_WRITING, &pc->flags)) {
1333 idetape_output_buffers(drive, pc, bcount);
1335 /* Write the current buffer */
1336 hwif->atapi_output_bytes(drive, pc->current_position,
1340 idetape_input_buffers(drive, pc, bcount);
1342 /* Read the current buffer */
1343 hwif->atapi_input_bytes(drive, pc->current_position,
1346 /* Update the current position */
1347 pc->actually_transferred += bcount;
1348 pc->current_position += bcount;
1349 #if IDETAPE_DEBUG_LOG
1350 if (tape->debug_level >= 2)
1351 printk(KERN_INFO "ide-tape: [cmd %x] transferred %d bytes "
1352 "on that interrupt\n", pc->c[0], bcount);
1354 /* And set the interrupt handler again */
1355 ide_set_handler(drive, &idetape_pc_intr, IDETAPE_WAIT_CMD, NULL);
1360 * Packet Command Interface
1362 * The current Packet Command is available in tape->pc, and will not
1363 * change until we finish handling it. Each packet command is associated
1364 * with a callback function that will be called when the command is
1367 * The handling will be done in three stages:
1369 * 1. idetape_issue_packet_command will send the packet command to the
1370 * drive, and will set the interrupt handler to idetape_pc_intr.
1372 * 2. On each interrupt, idetape_pc_intr will be called. This step
1373 * will be repeated until the device signals us that no more
1374 * interrupts will be issued.
1376 * 3. ATAPI Tape media access commands have immediate status with a
1377 * delayed process. In case of a successful initiation of a
1378 * media access packet command, the DSC bit will be set when the
1379 * actual execution of the command is finished.
1380 * Since the tape drive will not issue an interrupt, we have to
1381 * poll for this event. In this case, we define the request as
1382 * "low priority request" by setting rq_status to
1383 * IDETAPE_RQ_POSTPONED, set a timer to poll for DSC and exit
1386 * ide.c will then give higher priority to requests which
1387 * originate from the other device, until will change rq_status
1390 * 4. When the packet command is finished, it will be checked for errors.
1392 * 5. In case an error was found, we queue a request sense packet
1393 * command in front of the request queue and retry the operation
1394 * up to IDETAPE_MAX_PC_RETRIES times.
1396 * 6. In case no error was found, or we decided to give up and not
1397 * to retry again, the callback function will be called and then
1398 * we will handle the next request.
1401 static ide_startstop_t idetape_transfer_pc(ide_drive_t *drive)
1403 ide_hwif_t *hwif = drive->hwif;
1404 idetape_tape_t *tape = drive->driver_data;
1405 idetape_pc_t *pc = tape->pc;
1407 ide_startstop_t startstop;
1410 if (ide_wait_stat(&startstop,drive,DRQ_STAT,BUSY_STAT,WAIT_READY)) {
1411 printk(KERN_ERR "ide-tape: Strange, packet command initiated yet DRQ isn't asserted\n");
1414 ireason = hwif->INB(IDE_IREASON_REG);
1415 while (retries-- && ((ireason & CD) == 0 || (ireason & IO))) {
1416 printk(KERN_ERR "ide-tape: (IO,CoD != (0,1) while issuing "
1417 "a packet command, retrying\n");
1419 ireason = hwif->INB(IDE_IREASON_REG);
1421 printk(KERN_ERR "ide-tape: (IO,CoD != (0,1) while "
1422 "issuing a packet command, ignoring\n");
1427 if ((ireason & CD) == 0 || (ireason & IO)) {
1428 printk(KERN_ERR "ide-tape: (IO,CoD) != (0,1) while issuing "
1429 "a packet command\n");
1430 return ide_do_reset(drive);
1432 /* Set the interrupt routine */
1433 ide_set_handler(drive, &idetape_pc_intr, IDETAPE_WAIT_CMD, NULL);
1434 #ifdef CONFIG_BLK_DEV_IDEDMA
1435 /* Begin DMA, if necessary */
1436 if (test_bit(PC_DMA_IN_PROGRESS, &pc->flags))
1437 hwif->dma_start(drive);
1439 /* Send the actual packet */
1440 HWIF(drive)->atapi_output_bytes(drive, pc->c, 12);
1444 static ide_startstop_t idetape_issue_packet_command (ide_drive_t *drive, idetape_pc_t *pc)
1446 ide_hwif_t *hwif = drive->hwif;
1447 idetape_tape_t *tape = drive->driver_data;
1451 if (tape->pc->c[0] == REQUEST_SENSE &&
1452 pc->c[0] == REQUEST_SENSE) {
1453 printk(KERN_ERR "ide-tape: possible ide-tape.c bug - "
1454 "Two request sense in serial were issued\n");
1457 if (tape->failed_pc == NULL && pc->c[0] != REQUEST_SENSE)
1458 tape->failed_pc = pc;
1459 /* Set the current packet command */
1462 if (pc->retries > IDETAPE_MAX_PC_RETRIES ||
1463 test_bit(PC_ABORT, &pc->flags)) {
1465 * We will "abort" retrying a packet command in case
1466 * a legitimate error code was received (crossing a
1467 * filemark, or end of the media, for example).
1469 if (!test_bit(PC_ABORT, &pc->flags)) {
1470 if (!(pc->c[0] == TEST_UNIT_READY &&
1471 tape->sense_key == 2 && tape->asc == 4 &&
1472 (tape->ascq == 1 || tape->ascq == 8))) {
1473 printk(KERN_ERR "ide-tape: %s: I/O error, "
1474 "pc = %2x, key = %2x, "
1475 "asc = %2x, ascq = %2x\n",
1476 tape->name, pc->c[0],
1477 tape->sense_key, tape->asc,
1481 pc->error = IDETAPE_ERROR_GENERAL;
1483 tape->failed_pc = NULL;
1484 return pc->callback(drive);
1486 #if IDETAPE_DEBUG_LOG
1487 if (tape->debug_level >= 2)
1488 printk(KERN_INFO "ide-tape: Retry number - %d, cmd = %02X\n", pc->retries, pc->c[0]);
1489 #endif /* IDETAPE_DEBUG_LOG */
1492 /* We haven't transferred any data yet */
1493 pc->actually_transferred = 0;
1494 pc->current_position = pc->buffer;
1495 /* Request to transfer the entire buffer at once */
1496 bcount = pc->request_transfer;
1498 if (test_and_clear_bit(PC_DMA_ERROR, &pc->flags)) {
1499 printk(KERN_WARNING "ide-tape: DMA disabled, "
1500 "reverting to PIO\n");
1503 if (test_bit(PC_DMA_RECOMMENDED, &pc->flags) && drive->using_dma)
1504 dma_ok = !hwif->dma_setup(drive);
1506 ide_pktcmd_tf_load(drive, IDE_TFLAG_NO_SELECT_MASK |
1507 IDE_TFLAG_OUT_DEVICE, bcount, dma_ok);
1509 if (dma_ok) /* Will begin DMA later */
1510 set_bit(PC_DMA_IN_PROGRESS, &pc->flags);
1511 if (test_bit(IDETAPE_DRQ_INTERRUPT, &tape->flags)) {
1512 ide_execute_command(drive, WIN_PACKETCMD, &idetape_transfer_pc,
1513 IDETAPE_WAIT_CMD, NULL);
1516 hwif->OUTB(WIN_PACKETCMD, IDE_COMMAND_REG);
1517 return idetape_transfer_pc(drive);
1522 * General packet command callback function.
1524 static ide_startstop_t idetape_pc_callback (ide_drive_t *drive)
1526 idetape_tape_t *tape = drive->driver_data;
1528 #if IDETAPE_DEBUG_LOG
1529 if (tape->debug_level >= 4)
1530 printk(KERN_INFO "ide-tape: Reached idetape_pc_callback\n");
1531 #endif /* IDETAPE_DEBUG_LOG */
1533 idetape_end_request(drive, tape->pc->error ? 0 : 1, 0);
1538 * A mode sense command is used to "sense" tape parameters.
1540 static void idetape_create_mode_sense_cmd (idetape_pc_t *pc, u8 page_code)
1542 idetape_init_pc(pc);
1543 pc->c[0] = MODE_SENSE;
1544 if (page_code != IDETAPE_BLOCK_DESCRIPTOR)
1545 pc->c[1] = 8; /* DBD = 1 - Don't return block descriptors */
1546 pc->c[2] = page_code;
1548 * Changed pc->c[3] to 0 (255 will at best return unused info).
1550 * For SCSI this byte is defined as subpage instead of high byte
1551 * of length and some IDE drives seem to interpret it this way
1552 * and return an error when 255 is used.
1555 pc->c[4] = 255; /* (We will just discard data in that case) */
1556 if (page_code == IDETAPE_BLOCK_DESCRIPTOR)
1557 pc->request_transfer = 12;
1558 else if (page_code == IDETAPE_CAPABILITIES_PAGE)
1559 pc->request_transfer = 24;
1561 pc->request_transfer = 50;
1562 pc->callback = &idetape_pc_callback;
1565 static void calculate_speeds(ide_drive_t *drive)
1567 idetape_tape_t *tape = drive->driver_data;
1568 int full = 125, empty = 75;
1570 if (time_after(jiffies, tape->controlled_pipeline_head_time + 120 * HZ)) {
1571 tape->controlled_previous_pipeline_head = tape->controlled_last_pipeline_head;
1572 tape->controlled_previous_head_time = tape->controlled_pipeline_head_time;
1573 tape->controlled_last_pipeline_head = tape->pipeline_head;
1574 tape->controlled_pipeline_head_time = jiffies;
1576 if (time_after(jiffies, tape->controlled_pipeline_head_time + 60 * HZ))
1577 tape->controlled_pipeline_head_speed = (tape->pipeline_head - tape->controlled_last_pipeline_head) * 32 * HZ / (jiffies - tape->controlled_pipeline_head_time);
1578 else if (time_after(jiffies, tape->controlled_previous_head_time))
1579 tape->controlled_pipeline_head_speed = (tape->pipeline_head - tape->controlled_previous_pipeline_head) * 32 * HZ / (jiffies - tape->controlled_previous_head_time);
1581 if (tape->nr_pending_stages < tape->max_stages /*- 1 */) {
1582 /* -1 for read mode error recovery */
1583 if (time_after(jiffies, tape->uncontrolled_previous_head_time + 10 * HZ)) {
1584 tape->uncontrolled_pipeline_head_time = jiffies;
1585 tape->uncontrolled_pipeline_head_speed = (tape->pipeline_head - tape->uncontrolled_previous_pipeline_head) * 32 * HZ / (jiffies - tape->uncontrolled_previous_head_time);
1588 tape->uncontrolled_previous_head_time = jiffies;
1589 tape->uncontrolled_previous_pipeline_head = tape->pipeline_head;
1590 if (time_after(jiffies, tape->uncontrolled_pipeline_head_time + 30 * HZ)) {
1591 tape->uncontrolled_pipeline_head_time = jiffies;
1594 tape->pipeline_head_speed = max(tape->uncontrolled_pipeline_head_speed, tape->controlled_pipeline_head_speed);
1595 if (tape->speed_control == 0) {
1596 tape->max_insert_speed = 5000;
1597 } else if (tape->speed_control == 1) {
1598 if (tape->nr_pending_stages >= tape->max_stages / 2)
1599 tape->max_insert_speed = tape->pipeline_head_speed +
1600 (1100 - tape->pipeline_head_speed) * 2 * (tape->nr_pending_stages - tape->max_stages / 2) / tape->max_stages;
1602 tape->max_insert_speed = 500 +
1603 (tape->pipeline_head_speed - 500) * 2 * tape->nr_pending_stages / tape->max_stages;
1604 if (tape->nr_pending_stages >= tape->max_stages * 99 / 100)
1605 tape->max_insert_speed = 5000;
1606 } else if (tape->speed_control == 2) {
1607 tape->max_insert_speed = tape->pipeline_head_speed * empty / 100 +
1608 (tape->pipeline_head_speed * full / 100 - tape->pipeline_head_speed * empty / 100) * tape->nr_pending_stages / tape->max_stages;
1610 tape->max_insert_speed = tape->speed_control;
1611 tape->max_insert_speed = max(tape->max_insert_speed, 500);
1614 static ide_startstop_t idetape_media_access_finished (ide_drive_t *drive)
1616 idetape_tape_t *tape = drive->driver_data;
1617 idetape_pc_t *pc = tape->pc;
1620 stat = drive->hwif->INB(IDE_STATUS_REG);
1621 if (stat & SEEK_STAT) {
1622 if (stat & ERR_STAT) {
1623 /* Error detected */
1624 if (pc->c[0] != TEST_UNIT_READY)
1625 printk(KERN_ERR "ide-tape: %s: I/O error, ",
1627 /* Retry operation */
1628 return idetape_retry_pc(drive);
1631 if (tape->failed_pc == pc)
1632 tape->failed_pc = NULL;
1634 pc->error = IDETAPE_ERROR_GENERAL;
1635 tape->failed_pc = NULL;
1637 return pc->callback(drive);
1640 static ide_startstop_t idetape_rw_callback (ide_drive_t *drive)
1642 idetape_tape_t *tape = drive->driver_data;
1643 struct request *rq = HWGROUP(drive)->rq;
1644 int blocks = tape->pc->actually_transferred / tape->tape_block_size;
1646 tape->avg_size += blocks * tape->tape_block_size;
1647 tape->insert_size += blocks * tape->tape_block_size;
1648 if (tape->insert_size > 1024 * 1024)
1649 tape->measure_insert_time = 1;
1650 if (tape->measure_insert_time) {
1651 tape->measure_insert_time = 0;
1652 tape->insert_time = jiffies;
1653 tape->insert_size = 0;
1655 if (time_after(jiffies, tape->insert_time))
1656 tape->insert_speed = tape->insert_size / 1024 * HZ / (jiffies - tape->insert_time);
1657 if (time_after_eq(jiffies, tape->avg_time + HZ)) {
1658 tape->avg_speed = tape->avg_size * HZ / (jiffies - tape->avg_time) / 1024;
1660 tape->avg_time = jiffies;
1663 #if IDETAPE_DEBUG_LOG
1664 if (tape->debug_level >= 4)
1665 printk(KERN_INFO "ide-tape: Reached idetape_rw_callback\n");
1666 #endif /* IDETAPE_DEBUG_LOG */
1668 tape->first_frame_position += blocks;
1669 rq->current_nr_sectors -= blocks;
1671 if (!tape->pc->error)
1672 idetape_end_request(drive, 1, 0);
1674 idetape_end_request(drive, tape->pc->error, 0);
1678 static void idetape_create_read_cmd(idetape_tape_t *tape, idetape_pc_t *pc, unsigned int length, struct idetape_bh *bh)
1680 idetape_init_pc(pc);
1682 put_unaligned(htonl(length), (unsigned int *) &pc->c[1]);
1684 pc->callback = &idetape_rw_callback;
1686 atomic_set(&bh->b_count, 0);
1688 pc->request_transfer = pc->buffer_size = length * tape->tape_block_size;
1689 if (pc->request_transfer == tape->stage_size)
1690 set_bit(PC_DMA_RECOMMENDED, &pc->flags);
1693 static void idetape_create_read_buffer_cmd(idetape_tape_t *tape, idetape_pc_t *pc, unsigned int length, struct idetape_bh *bh)
1696 struct idetape_bh *p = bh;
1698 idetape_init_pc(pc);
1699 pc->c[0] = READ_BUFFER;
1700 pc->c[1] = IDETAPE_RETRIEVE_FAULTY_BLOCK;
1701 pc->c[7] = size >> 8;
1702 pc->c[8] = size & 0xff;
1703 pc->callback = &idetape_pc_callback;
1705 atomic_set(&bh->b_count, 0);
1708 atomic_set(&p->b_count, 0);
1711 pc->request_transfer = pc->buffer_size = size;
1714 static void idetape_create_write_cmd(idetape_tape_t *tape, idetape_pc_t *pc, unsigned int length, struct idetape_bh *bh)
1716 idetape_init_pc(pc);
1718 put_unaligned(htonl(length), (unsigned int *) &pc->c[1]);
1720 pc->callback = &idetape_rw_callback;
1721 set_bit(PC_WRITING, &pc->flags);
1723 pc->b_data = bh->b_data;
1724 pc->b_count = atomic_read(&bh->b_count);
1726 pc->request_transfer = pc->buffer_size = length * tape->tape_block_size;
1727 if (pc->request_transfer == tape->stage_size)
1728 set_bit(PC_DMA_RECOMMENDED, &pc->flags);
1732 * idetape_do_request is our request handling function.
1734 static ide_startstop_t idetape_do_request(ide_drive_t *drive,
1735 struct request *rq, sector_t block)
1737 idetape_tape_t *tape = drive->driver_data;
1738 idetape_pc_t *pc = NULL;
1739 struct request *postponed_rq = tape->postponed_rq;
1742 #if IDETAPE_DEBUG_LOG
1743 if (tape->debug_level >= 2)
1744 printk(KERN_INFO "ide-tape: sector: %ld, "
1745 "nr_sectors: %ld, current_nr_sectors: %d\n",
1746 rq->sector, rq->nr_sectors, rq->current_nr_sectors);
1747 #endif /* IDETAPE_DEBUG_LOG */
1749 if (!blk_special_request(rq)) {
1751 * We do not support buffer cache originated requests.
1753 printk(KERN_NOTICE "ide-tape: %s: Unsupported request in "
1754 "request queue (%d)\n", drive->name, rq->cmd_type);
1755 ide_end_request(drive, 0, 0);
1760 * Retry a failed packet command
1762 if (tape->failed_pc != NULL &&
1763 tape->pc->c[0] == REQUEST_SENSE) {
1764 return idetape_issue_packet_command(drive, tape->failed_pc);
1766 if (postponed_rq != NULL)
1767 if (rq != postponed_rq) {
1768 printk(KERN_ERR "ide-tape: ide-tape.c bug - "
1769 "Two DSC requests were queued\n");
1770 idetape_end_request(drive, 0, 0);
1774 tape->postponed_rq = NULL;
1777 * If the tape is still busy, postpone our request and service
1778 * the other device meanwhile.
1780 stat = drive->hwif->INB(IDE_STATUS_REG);
1782 if (!drive->dsc_overlap && !(rq->cmd[0] & REQ_IDETAPE_PC2))
1783 set_bit(IDETAPE_IGNORE_DSC, &tape->flags);
1785 if (drive->post_reset == 1) {
1786 set_bit(IDETAPE_IGNORE_DSC, &tape->flags);
1787 drive->post_reset = 0;
1790 if (tape->tape_still_time > 100 && tape->tape_still_time < 200)
1791 tape->measure_insert_time = 1;
1792 if (time_after(jiffies, tape->insert_time))
1793 tape->insert_speed = tape->insert_size / 1024 * HZ / (jiffies - tape->insert_time);
1794 calculate_speeds(drive);
1795 if (!test_and_clear_bit(IDETAPE_IGNORE_DSC, &tape->flags) &&
1796 (stat & SEEK_STAT) == 0) {
1797 if (postponed_rq == NULL) {
1798 tape->dsc_polling_start = jiffies;
1799 tape->dsc_polling_frequency = tape->best_dsc_rw_frequency;
1800 tape->dsc_timeout = jiffies + IDETAPE_DSC_RW_TIMEOUT;
1801 } else if (time_after(jiffies, tape->dsc_timeout)) {
1802 printk(KERN_ERR "ide-tape: %s: DSC timeout\n",
1804 if (rq->cmd[0] & REQ_IDETAPE_PC2) {
1805 idetape_media_access_finished(drive);
1808 return ide_do_reset(drive);
1810 } else if (time_after(jiffies, tape->dsc_polling_start + IDETAPE_DSC_MA_THRESHOLD))
1811 tape->dsc_polling_frequency = IDETAPE_DSC_MA_SLOW;
1812 idetape_postpone_request(drive);
1815 if (rq->cmd[0] & REQ_IDETAPE_READ) {
1816 tape->buffer_head++;
1817 tape->postpone_cnt = 0;
1818 pc = idetape_next_pc_storage(drive);
1819 idetape_create_read_cmd(tape, pc, rq->current_nr_sectors, (struct idetape_bh *)rq->special);
1822 if (rq->cmd[0] & REQ_IDETAPE_WRITE) {
1823 tape->buffer_head++;
1824 tape->postpone_cnt = 0;
1825 pc = idetape_next_pc_storage(drive);
1826 idetape_create_write_cmd(tape, pc, rq->current_nr_sectors, (struct idetape_bh *)rq->special);
1829 if (rq->cmd[0] & REQ_IDETAPE_READ_BUFFER) {
1830 tape->postpone_cnt = 0;
1831 pc = idetape_next_pc_storage(drive);
1832 idetape_create_read_buffer_cmd(tape, pc, rq->current_nr_sectors, (struct idetape_bh *)rq->special);
1835 if (rq->cmd[0] & REQ_IDETAPE_PC1) {
1836 pc = (idetape_pc_t *) rq->buffer;
1837 rq->cmd[0] &= ~(REQ_IDETAPE_PC1);
1838 rq->cmd[0] |= REQ_IDETAPE_PC2;
1841 if (rq->cmd[0] & REQ_IDETAPE_PC2) {
1842 idetape_media_access_finished(drive);
1847 return idetape_issue_packet_command(drive, pc);
1851 * Pipeline related functions
1853 static inline int idetape_pipeline_active (idetape_tape_t *tape)
1857 rc1 = test_bit(IDETAPE_PIPELINE_ACTIVE, &tape->flags);
1858 rc2 = (tape->active_data_request != NULL);
1863 * idetape_kmalloc_stage uses __get_free_page to allocate a pipeline
1864 * stage, along with all the necessary small buffers which together make
1865 * a buffer of size tape->stage_size (or a bit more). We attempt to
1866 * combine sequential pages as much as possible.
1868 * Returns a pointer to the new allocated stage, or NULL if we
1869 * can't (or don't want to) allocate a stage.
1871 * Pipeline stages are optional and are used to increase performance.
1872 * If we can't allocate them, we'll manage without them.
1874 static idetape_stage_t *__idetape_kmalloc_stage (idetape_tape_t *tape, int full, int clear)
1876 idetape_stage_t *stage;
1877 struct idetape_bh *prev_bh, *bh;
1878 int pages = tape->pages_per_stage;
1879 char *b_data = NULL;
1881 if ((stage = kmalloc(sizeof (idetape_stage_t),GFP_KERNEL)) == NULL)
1885 bh = stage->bh = kmalloc(sizeof(struct idetape_bh), GFP_KERNEL);
1888 bh->b_reqnext = NULL;
1889 if ((bh->b_data = (char *) __get_free_page (GFP_KERNEL)) == NULL)
1892 memset(bh->b_data, 0, PAGE_SIZE);
1893 bh->b_size = PAGE_SIZE;
1894 atomic_set(&bh->b_count, full ? bh->b_size : 0);
1897 if ((b_data = (char *) __get_free_page (GFP_KERNEL)) == NULL)
1900 memset(b_data, 0, PAGE_SIZE);
1901 if (bh->b_data == b_data + PAGE_SIZE) {
1902 bh->b_size += PAGE_SIZE;
1903 bh->b_data -= PAGE_SIZE;
1905 atomic_add(PAGE_SIZE, &bh->b_count);
1908 if (b_data == bh->b_data + bh->b_size) {
1909 bh->b_size += PAGE_SIZE;
1911 atomic_add(PAGE_SIZE, &bh->b_count);
1915 if ((bh = kmalloc(sizeof(struct idetape_bh), GFP_KERNEL)) == NULL) {
1916 free_page((unsigned long) b_data);
1919 bh->b_reqnext = NULL;
1920 bh->b_data = b_data;
1921 bh->b_size = PAGE_SIZE;
1922 atomic_set(&bh->b_count, full ? bh->b_size : 0);
1923 prev_bh->b_reqnext = bh;
1925 bh->b_size -= tape->excess_bh_size;
1927 atomic_sub(tape->excess_bh_size, &bh->b_count);
1930 __idetape_kfree_stage(stage);
1934 static idetape_stage_t *idetape_kmalloc_stage (idetape_tape_t *tape)
1936 idetape_stage_t *cache_stage = tape->cache_stage;
1938 #if IDETAPE_DEBUG_LOG
1939 if (tape->debug_level >= 4)
1940 printk(KERN_INFO "ide-tape: Reached idetape_kmalloc_stage\n");
1941 #endif /* IDETAPE_DEBUG_LOG */
1943 if (tape->nr_stages >= tape->max_stages)
1945 if (cache_stage != NULL) {
1946 tape->cache_stage = NULL;
1949 return __idetape_kmalloc_stage(tape, 0, 0);
1952 static int idetape_copy_stage_from_user (idetape_tape_t *tape, idetape_stage_t *stage, const char __user *buf, int n)
1954 struct idetape_bh *bh = tape->bh;
1960 printk(KERN_ERR "ide-tape: bh == NULL in "
1961 "idetape_copy_stage_from_user\n");
1964 count = min((unsigned int)(bh->b_size - atomic_read(&bh->b_count)), (unsigned int)n);
1965 if (copy_from_user(bh->b_data + atomic_read(&bh->b_count), buf, count))
1968 atomic_add(count, &bh->b_count);
1970 if (atomic_read(&bh->b_count) == bh->b_size) {
1973 atomic_set(&bh->b_count, 0);
1980 static int idetape_copy_stage_to_user (idetape_tape_t *tape, char __user *buf, idetape_stage_t *stage, int n)
1982 struct idetape_bh *bh = tape->bh;
1988 printk(KERN_ERR "ide-tape: bh == NULL in "
1989 "idetape_copy_stage_to_user\n");
1992 count = min(tape->b_count, n);
1993 if (copy_to_user(buf, tape->b_data, count))
1996 tape->b_data += count;
1997 tape->b_count -= count;
1999 if (!tape->b_count) {
2000 tape->bh = bh = bh->b_reqnext;
2002 tape->b_data = bh->b_data;
2003 tape->b_count = atomic_read(&bh->b_count);
2010 static void idetape_init_merge_stage (idetape_tape_t *tape)
2012 struct idetape_bh *bh = tape->merge_stage->bh;
2015 if (tape->chrdev_direction == idetape_direction_write)
2016 atomic_set(&bh->b_count, 0);
2018 tape->b_data = bh->b_data;
2019 tape->b_count = atomic_read(&bh->b_count);
2023 static void idetape_switch_buffers (idetape_tape_t *tape, idetape_stage_t *stage)
2025 struct idetape_bh *tmp;
2028 stage->bh = tape->merge_stage->bh;
2029 tape->merge_stage->bh = tmp;
2030 idetape_init_merge_stage(tape);
2034 * idetape_add_stage_tail adds a new stage at the end of the pipeline.
2036 static void idetape_add_stage_tail (ide_drive_t *drive,idetape_stage_t *stage)
2038 idetape_tape_t *tape = drive->driver_data;
2039 unsigned long flags;
2041 #if IDETAPE_DEBUG_LOG
2042 if (tape->debug_level >= 4)
2043 printk (KERN_INFO "ide-tape: Reached idetape_add_stage_tail\n");
2044 #endif /* IDETAPE_DEBUG_LOG */
2045 spin_lock_irqsave(&tape->spinlock, flags);
2047 if (tape->last_stage != NULL)
2048 tape->last_stage->next=stage;
2050 tape->first_stage = tape->next_stage=stage;
2051 tape->last_stage = stage;
2052 if (tape->next_stage == NULL)
2053 tape->next_stage = tape->last_stage;
2055 tape->nr_pending_stages++;
2056 spin_unlock_irqrestore(&tape->spinlock, flags);
2060 * idetape_wait_for_request installs a completion in a pending request
2061 * and sleeps until it is serviced.
2063 * The caller should ensure that the request will not be serviced
2064 * before we install the completion (usually by disabling interrupts).
2066 static void idetape_wait_for_request (ide_drive_t *drive, struct request *rq)
2068 DECLARE_COMPLETION_ONSTACK(wait);
2069 idetape_tape_t *tape = drive->driver_data;
2071 if (rq == NULL || !blk_special_request(rq)) {
2072 printk (KERN_ERR "ide-tape: bug: Trying to sleep on non-valid request\n");
2075 rq->end_io_data = &wait;
2076 rq->end_io = blk_end_sync_rq;
2077 spin_unlock_irq(&tape->spinlock);
2078 wait_for_completion(&wait);
2079 /* The stage and its struct request have been deallocated */
2080 spin_lock_irq(&tape->spinlock);
2083 static ide_startstop_t idetape_read_position_callback (ide_drive_t *drive)
2085 idetape_tape_t *tape = drive->driver_data;
2086 idetape_read_position_result_t *result;
2088 #if IDETAPE_DEBUG_LOG
2089 if (tape->debug_level >= 4)
2090 printk(KERN_INFO "ide-tape: Reached idetape_read_position_callback\n");
2091 #endif /* IDETAPE_DEBUG_LOG */
2093 if (!tape->pc->error) {
2094 result = (idetape_read_position_result_t *) tape->pc->buffer;
2095 #if IDETAPE_DEBUG_LOG
2096 if (tape->debug_level >= 2)
2097 printk(KERN_INFO "ide-tape: BOP - %s\n",result->bop ? "Yes":"No");
2098 if (tape->debug_level >= 2)
2099 printk(KERN_INFO "ide-tape: EOP - %s\n",result->eop ? "Yes":"No");
2100 #endif /* IDETAPE_DEBUG_LOG */
2102 printk(KERN_INFO "ide-tape: Block location is unknown to the tape\n");
2103 clear_bit(IDETAPE_ADDRESS_VALID, &tape->flags);
2104 idetape_end_request(drive, 0, 0);
2106 #if IDETAPE_DEBUG_LOG
2107 if (tape->debug_level >= 2)
2108 printk(KERN_INFO "ide-tape: Block Location - %u\n", ntohl(result->first_block));
2109 #endif /* IDETAPE_DEBUG_LOG */
2110 tape->partition = result->partition;
2111 tape->first_frame_position = ntohl(result->first_block);
2112 tape->last_frame_position = ntohl(result->last_block);
2113 tape->blocks_in_buffer = result->blocks_in_buffer[2];
2114 set_bit(IDETAPE_ADDRESS_VALID, &tape->flags);
2115 idetape_end_request(drive, 1, 0);
2118 idetape_end_request(drive, 0, 0);
2124 * idetape_create_write_filemark_cmd will:
2126 * 1. Write a filemark if write_filemark=1.
2127 * 2. Flush the device buffers without writing a filemark
2128 * if write_filemark=0.
2131 static void idetape_create_write_filemark_cmd (ide_drive_t *drive, idetape_pc_t *pc,int write_filemark)
2133 idetape_init_pc(pc);
2134 pc->c[0] = WRITE_FILEMARKS;
2135 pc->c[4] = write_filemark;
2136 set_bit(PC_WAIT_FOR_DSC, &pc->flags);
2137 pc->callback = &idetape_pc_callback;
2140 static void idetape_create_test_unit_ready_cmd(idetape_pc_t *pc)
2142 idetape_init_pc(pc);
2143 pc->c[0] = TEST_UNIT_READY;
2144 pc->callback = &idetape_pc_callback;
2148 * idetape_queue_pc_tail is based on the following functions:
2150 * ide_do_drive_cmd from ide.c
2151 * cdrom_queue_request and cdrom_queue_packet_command from ide-cd.c
2153 * We add a special packet command request to the tail of the request
2154 * queue, and wait for it to be serviced.
2156 * This is not to be called from within the request handling part
2157 * of the driver ! We allocate here data in the stack, and it is valid
2158 * until the request is finished. This is not the case for the bottom
2159 * part of the driver, where we are always leaving the functions to wait
2160 * for an interrupt or a timer event.
2162 * From the bottom part of the driver, we should allocate safe memory
2163 * using idetape_next_pc_storage and idetape_next_rq_storage, and add
2164 * the request to the request list without waiting for it to be serviced !
2165 * In that case, we usually use idetape_queue_pc_head.
2167 static int __idetape_queue_pc_tail (ide_drive_t *drive, idetape_pc_t *pc)
2169 struct ide_tape_obj *tape = drive->driver_data;
2172 idetape_init_rq(&rq, REQ_IDETAPE_PC1);
2173 rq.buffer = (char *) pc;
2174 rq.rq_disk = tape->disk;
2175 return ide_do_drive_cmd(drive, &rq, ide_wait);
2178 static void idetape_create_load_unload_cmd (ide_drive_t *drive, idetape_pc_t *pc,int cmd)
2180 idetape_init_pc(pc);
2181 pc->c[0] = START_STOP;
2183 set_bit(PC_WAIT_FOR_DSC, &pc->flags);
2184 pc->callback = &idetape_pc_callback;
2187 static int idetape_wait_ready(ide_drive_t *drive, unsigned long timeout)
2189 idetape_tape_t *tape = drive->driver_data;
2191 int load_attempted = 0;
2194 * Wait for the tape to become ready
2196 set_bit(IDETAPE_MEDIUM_PRESENT, &tape->flags);
2198 while (time_before(jiffies, timeout)) {
2199 idetape_create_test_unit_ready_cmd(&pc);
2200 if (!__idetape_queue_pc_tail(drive, &pc))
2202 if ((tape->sense_key == 2 && tape->asc == 4 && tape->ascq == 2)
2203 || (tape->asc == 0x3A)) { /* no media */
2206 idetape_create_load_unload_cmd(drive, &pc, IDETAPE_LU_LOAD_MASK);
2207 __idetape_queue_pc_tail(drive, &pc);
2209 /* not about to be ready */
2210 } else if (!(tape->sense_key == 2 && tape->asc == 4 &&
2211 (tape->ascq == 1 || tape->ascq == 8)))
2218 static int idetape_queue_pc_tail (ide_drive_t *drive,idetape_pc_t *pc)
2220 return __idetape_queue_pc_tail(drive, pc);
2223 static int idetape_flush_tape_buffers (ide_drive_t *drive)
2228 idetape_create_write_filemark_cmd(drive, &pc, 0);
2229 if ((rc = idetape_queue_pc_tail(drive, &pc)))
2231 idetape_wait_ready(drive, 60 * 5 * HZ);
2235 static void idetape_create_read_position_cmd (idetape_pc_t *pc)
2237 idetape_init_pc(pc);
2238 pc->c[0] = READ_POSITION;
2239 pc->request_transfer = 20;
2240 pc->callback = &idetape_read_position_callback;
2243 static int idetape_read_position (ide_drive_t *drive)
2245 idetape_tape_t *tape = drive->driver_data;
2249 #if IDETAPE_DEBUG_LOG
2250 if (tape->debug_level >= 4)
2251 printk(KERN_INFO "ide-tape: Reached idetape_read_position\n");
2252 #endif /* IDETAPE_DEBUG_LOG */
2254 idetape_create_read_position_cmd(&pc);
2255 if (idetape_queue_pc_tail(drive, &pc))
2257 position = tape->first_frame_position;
2261 static void idetape_create_locate_cmd (ide_drive_t *drive, idetape_pc_t *pc, unsigned int block, u8 partition, int skip)
2263 idetape_init_pc(pc);
2264 pc->c[0] = POSITION_TO_ELEMENT;
2266 put_unaligned(htonl(block), (unsigned int *) &pc->c[3]);
2267 pc->c[8] = partition;
2268 set_bit(PC_WAIT_FOR_DSC, &pc->flags);
2269 pc->callback = &idetape_pc_callback;
2272 static int idetape_create_prevent_cmd (ide_drive_t *drive, idetape_pc_t *pc, int prevent)
2274 idetape_tape_t *tape = drive->driver_data;
2276 /* device supports locking according to capabilities page */
2277 if (!(tape->caps[6] & 0x01))
2280 idetape_init_pc(pc);
2281 pc->c[0] = ALLOW_MEDIUM_REMOVAL;
2283 pc->callback = &idetape_pc_callback;
2287 static int __idetape_discard_read_pipeline (ide_drive_t *drive)
2289 idetape_tape_t *tape = drive->driver_data;
2290 unsigned long flags;
2293 if (tape->chrdev_direction != idetape_direction_read)
2296 /* Remove merge stage. */
2297 cnt = tape->merge_stage_size / tape->tape_block_size;
2298 if (test_and_clear_bit(IDETAPE_FILEMARK, &tape->flags))
2299 ++cnt; /* Filemarks count as 1 sector */
2300 tape->merge_stage_size = 0;
2301 if (tape->merge_stage != NULL) {
2302 __idetape_kfree_stage(tape->merge_stage);
2303 tape->merge_stage = NULL;
2306 /* Clear pipeline flags. */
2307 clear_bit(IDETAPE_PIPELINE_ERROR, &tape->flags);
2308 tape->chrdev_direction = idetape_direction_none;
2310 /* Remove pipeline stages. */
2311 if (tape->first_stage == NULL)
2314 spin_lock_irqsave(&tape->spinlock, flags);
2315 tape->next_stage = NULL;
2316 if (idetape_pipeline_active(tape))
2317 idetape_wait_for_request(drive, tape->active_data_request);
2318 spin_unlock_irqrestore(&tape->spinlock, flags);
2320 while (tape->first_stage != NULL) {
2321 struct request *rq_ptr = &tape->first_stage->rq;
2323 cnt += rq_ptr->nr_sectors - rq_ptr->current_nr_sectors;
2324 if (rq_ptr->errors == IDETAPE_ERROR_FILEMARK)
2326 idetape_remove_stage_head(drive);
2328 tape->nr_pending_stages = 0;
2329 tape->max_stages = tape->min_pipeline;
2334 * idetape_position_tape positions the tape to the requested block
2335 * using the LOCATE packet command. A READ POSITION command is then
2336 * issued to check where we are positioned.
2338 * Like all higher level operations, we queue the commands at the tail
2339 * of the request queue and wait for their completion.
2342 static int idetape_position_tape (ide_drive_t *drive, unsigned int block, u8 partition, int skip)
2344 idetape_tape_t *tape = drive->driver_data;
2348 if (tape->chrdev_direction == idetape_direction_read)
2349 __idetape_discard_read_pipeline(drive);
2350 idetape_wait_ready(drive, 60 * 5 * HZ);
2351 idetape_create_locate_cmd(drive, &pc, block, partition, skip);
2352 retval = idetape_queue_pc_tail(drive, &pc);
2356 idetape_create_read_position_cmd(&pc);
2357 return (idetape_queue_pc_tail(drive, &pc));
2360 static void idetape_discard_read_pipeline (ide_drive_t *drive, int restore_position)
2362 idetape_tape_t *tape = drive->driver_data;
2366 cnt = __idetape_discard_read_pipeline(drive);
2367 if (restore_position) {
2368 position = idetape_read_position(drive);
2369 seek = position > cnt ? position - cnt : 0;
2370 if (idetape_position_tape(drive, seek, 0, 0)) {
2371 printk(KERN_INFO "ide-tape: %s: position_tape failed in discard_pipeline()\n", tape->name);
2378 * idetape_queue_rw_tail generates a read/write request for the block
2379 * device interface and wait for it to be serviced.
2381 static int idetape_queue_rw_tail(ide_drive_t *drive, int cmd, int blocks, struct idetape_bh *bh)
2383 idetape_tape_t *tape = drive->driver_data;
2386 #if IDETAPE_DEBUG_LOG
2387 if (tape->debug_level >= 2)
2388 printk(KERN_INFO "ide-tape: idetape_queue_rw_tail: cmd=%d\n",cmd);
2389 #endif /* IDETAPE_DEBUG_LOG */
2390 if (idetape_pipeline_active(tape)) {
2391 printk(KERN_ERR "ide-tape: bug: the pipeline is active in idetape_queue_rw_tail\n");
2395 idetape_init_rq(&rq, cmd);
2396 rq.rq_disk = tape->disk;
2397 rq.special = (void *)bh;
2398 rq.sector = tape->first_frame_position;
2399 rq.nr_sectors = rq.current_nr_sectors = blocks;
2400 (void) ide_do_drive_cmd(drive, &rq, ide_wait);
2402 if ((cmd & (REQ_IDETAPE_READ | REQ_IDETAPE_WRITE)) == 0)
2405 if (tape->merge_stage)
2406 idetape_init_merge_stage(tape);
2407 if (rq.errors == IDETAPE_ERROR_GENERAL)
2409 return (tape->tape_block_size * (blocks-rq.current_nr_sectors));
2413 * idetape_insert_pipeline_into_queue is used to start servicing the
2414 * pipeline stages, starting from tape->next_stage.
2416 static void idetape_insert_pipeline_into_queue (ide_drive_t *drive)
2418 idetape_tape_t *tape = drive->driver_data;
2420 if (tape->next_stage == NULL)
2422 if (!idetape_pipeline_active(tape)) {
2423 set_bit(IDETAPE_PIPELINE_ACTIVE, &tape->flags);
2424 idetape_active_next_stage(drive);
2425 (void) ide_do_drive_cmd(drive, tape->active_data_request, ide_end);
2429 static void idetape_create_inquiry_cmd (idetape_pc_t *pc)
2431 idetape_init_pc(pc);
2433 pc->c[4] = pc->request_transfer = 254;
2434 pc->callback = &idetape_pc_callback;
2437 static void idetape_create_rewind_cmd (ide_drive_t *drive, idetape_pc_t *pc)
2439 idetape_init_pc(pc);
2440 pc->c[0] = REZERO_UNIT;
2441 set_bit(PC_WAIT_FOR_DSC, &pc->flags);
2442 pc->callback = &idetape_pc_callback;
2445 static void idetape_create_erase_cmd (idetape_pc_t *pc)
2447 idetape_init_pc(pc);
2450 set_bit(PC_WAIT_FOR_DSC, &pc->flags);
2451 pc->callback = &idetape_pc_callback;
2454 static void idetape_create_space_cmd (idetape_pc_t *pc,int count, u8 cmd)
2456 idetape_init_pc(pc);
2458 put_unaligned(htonl(count), (unsigned int *) &pc->c[1]);
2460 set_bit(PC_WAIT_FOR_DSC, &pc->flags);
2461 pc->callback = &idetape_pc_callback;
2464 static void idetape_wait_first_stage (ide_drive_t *drive)
2466 idetape_tape_t *tape = drive->driver_data;
2467 unsigned long flags;
2469 if (tape->first_stage == NULL)
2471 spin_lock_irqsave(&tape->spinlock, flags);
2472 if (tape->active_stage == tape->first_stage)
2473 idetape_wait_for_request(drive, tape->active_data_request);
2474 spin_unlock_irqrestore(&tape->spinlock, flags);
2478 * idetape_add_chrdev_write_request tries to add a character device
2479 * originated write request to our pipeline. In case we don't succeed,
2480 * we revert to non-pipelined operation mode for this request.
2482 * 1. Try to allocate a new pipeline stage.
2483 * 2. If we can't, wait for more and more requests to be serviced
2484 * and try again each time.
2485 * 3. If we still can't allocate a stage, fallback to
2486 * non-pipelined operation mode for this request.
2488 static int idetape_add_chrdev_write_request (ide_drive_t *drive, int blocks)
2490 idetape_tape_t *tape = drive->driver_data;
2491 idetape_stage_t *new_stage;
2492 unsigned long flags;
2495 #if IDETAPE_DEBUG_LOG
2496 if (tape->debug_level >= 3)
2497 printk(KERN_INFO "ide-tape: Reached idetape_add_chrdev_write_request\n");
2498 #endif /* IDETAPE_DEBUG_LOG */
2501 * Attempt to allocate a new stage.
2502 * Pay special attention to possible race conditions.
2504 while ((new_stage = idetape_kmalloc_stage(tape)) == NULL) {
2505 spin_lock_irqsave(&tape->spinlock, flags);
2506 if (idetape_pipeline_active(tape)) {
2507 idetape_wait_for_request(drive, tape->active_data_request);
2508 spin_unlock_irqrestore(&tape->spinlock, flags);
2510 spin_unlock_irqrestore(&tape->spinlock, flags);
2511 idetape_insert_pipeline_into_queue(drive);
2512 if (idetape_pipeline_active(tape))
2515 * Linux is short on memory. Fallback to
2516 * non-pipelined operation mode for this request.
2518 return idetape_queue_rw_tail(drive, REQ_IDETAPE_WRITE, blocks, tape->merge_stage->bh);
2521 rq = &new_stage->rq;
2522 idetape_init_rq(rq, REQ_IDETAPE_WRITE);
2523 /* Doesn't actually matter - We always assume sequential access */
2524 rq->sector = tape->first_frame_position;
2525 rq->nr_sectors = rq->current_nr_sectors = blocks;
2527 idetape_switch_buffers(tape, new_stage);
2528 idetape_add_stage_tail(drive, new_stage);
2529 tape->pipeline_head++;
2530 calculate_speeds(drive);
2533 * Estimate whether the tape has stopped writing by checking
2534 * if our write pipeline is currently empty. If we are not
2535 * writing anymore, wait for the pipeline to be full enough
2536 * (90%) before starting to service requests, so that we will
2537 * be able to keep up with the higher speeds of the tape.
2539 if (!idetape_pipeline_active(tape)) {
2540 if (tape->nr_stages >= tape->max_stages * 9 / 10 ||
2541 tape->nr_stages >= tape->max_stages - tape->uncontrolled_pipeline_head_speed * 3 * 1024 / tape->tape_block_size) {
2542 tape->measure_insert_time = 1;
2543 tape->insert_time = jiffies;
2544 tape->insert_size = 0;
2545 tape->insert_speed = 0;
2546 idetape_insert_pipeline_into_queue(drive);
2549 if (test_and_clear_bit(IDETAPE_PIPELINE_ERROR, &tape->flags))
2550 /* Return a deferred error */
2556 * idetape_wait_for_pipeline will wait until all pending pipeline
2557 * requests are serviced. Typically called on device close.
2559 static void idetape_wait_for_pipeline (ide_drive_t *drive)
2561 idetape_tape_t *tape = drive->driver_data;
2562 unsigned long flags;
2564 while (tape->next_stage || idetape_pipeline_active(tape)) {
2565 idetape_insert_pipeline_into_queue(drive);
2566 spin_lock_irqsave(&tape->spinlock, flags);
2567 if (idetape_pipeline_active(tape))
2568 idetape_wait_for_request(drive, tape->active_data_request);
2569 spin_unlock_irqrestore(&tape->spinlock, flags);
2573 static void idetape_empty_write_pipeline (ide_drive_t *drive)
2575 idetape_tape_t *tape = drive->driver_data;
2577 struct idetape_bh *bh;
2579 if (tape->chrdev_direction != idetape_direction_write) {
2580 printk(KERN_ERR "ide-tape: bug: Trying to empty write pipeline, but we are not writing.\n");
2583 if (tape->merge_stage_size > tape->stage_size) {
2584 printk(KERN_ERR "ide-tape: bug: merge_buffer too big\n");
2585 tape->merge_stage_size = tape->stage_size;
2587 if (tape->merge_stage_size) {
2588 blocks = tape->merge_stage_size / tape->tape_block_size;
2589 if (tape->merge_stage_size % tape->tape_block_size) {
2593 i = tape->tape_block_size - tape->merge_stage_size % tape->tape_block_size;
2594 bh = tape->bh->b_reqnext;
2596 atomic_set(&bh->b_count, 0);
2603 printk(KERN_INFO "ide-tape: bug, bh NULL\n");
2606 min = min(i, (unsigned int)(bh->b_size - atomic_read(&bh->b_count)));
2607 memset(bh->b_data + atomic_read(&bh->b_count), 0, min);
2608 atomic_add(min, &bh->b_count);
2613 (void) idetape_add_chrdev_write_request(drive, blocks);
2614 tape->merge_stage_size = 0;
2616 idetape_wait_for_pipeline(drive);
2617 if (tape->merge_stage != NULL) {
2618 __idetape_kfree_stage(tape->merge_stage);
2619 tape->merge_stage = NULL;
2621 clear_bit(IDETAPE_PIPELINE_ERROR, &tape->flags);
2622 tape->chrdev_direction = idetape_direction_none;
2625 * On the next backup, perform the feedback loop again.
2626 * (I don't want to keep sense information between backups,
2627 * as some systems are constantly on, and the system load
2628 * can be totally different on the next backup).
2630 tape->max_stages = tape->min_pipeline;
2631 if (tape->first_stage != NULL ||
2632 tape->next_stage != NULL ||
2633 tape->last_stage != NULL ||
2634 tape->nr_stages != 0) {
2635 printk(KERN_ERR "ide-tape: ide-tape pipeline bug, "
2636 "first_stage %p, next_stage %p, "
2637 "last_stage %p, nr_stages %d\n",
2638 tape->first_stage, tape->next_stage,
2639 tape->last_stage, tape->nr_stages);
2643 static void idetape_restart_speed_control (ide_drive_t *drive)
2645 idetape_tape_t *tape = drive->driver_data;
2647 tape->restart_speed_control_req = 0;
2648 tape->pipeline_head = 0;
2649 tape->controlled_last_pipeline_head = tape->uncontrolled_last_pipeline_head = 0;
2650 tape->controlled_previous_pipeline_head = tape->uncontrolled_previous_pipeline_head = 0;
2651 tape->pipeline_head_speed = tape->controlled_pipeline_head_speed = 5000;
2652 tape->uncontrolled_pipeline_head_speed = 0;
2653 tape->controlled_pipeline_head_time = tape->uncontrolled_pipeline_head_time = jiffies;
2654 tape->controlled_previous_head_time = tape->uncontrolled_previous_head_time = jiffies;
2657 static int idetape_initiate_read (ide_drive_t *drive, int max_stages)
2659 idetape_tape_t *tape = drive->driver_data;
2660 idetape_stage_t *new_stage;
2663 u16 blocks = *(u16 *)&tape->caps[12];
2665 /* Initialize read operation */
2666 if (tape->chrdev_direction != idetape_direction_read) {
2667 if (tape->chrdev_direction == idetape_direction_write) {
2668 idetape_empty_write_pipeline(drive);
2669 idetape_flush_tape_buffers(drive);
2671 if (tape->merge_stage || tape->merge_stage_size) {
2672 printk (KERN_ERR "ide-tape: merge_stage_size should be 0 now\n");
2673 tape->merge_stage_size = 0;
2675 if ((tape->merge_stage = __idetape_kmalloc_stage(tape, 0, 0)) == NULL)
2677 tape->chrdev_direction = idetape_direction_read;
2680 * Issue a read 0 command to ensure that DSC handshake
2681 * is switched from completion mode to buffer available
2683 * No point in issuing this if DSC overlap isn't supported,
2684 * some drives (Seagate STT3401A) will return an error.
2686 if (drive->dsc_overlap) {
2687 bytes_read = idetape_queue_rw_tail(drive, REQ_IDETAPE_READ, 0, tape->merge_stage->bh);
2688 if (bytes_read < 0) {
2689 __idetape_kfree_stage(tape->merge_stage);
2690 tape->merge_stage = NULL;
2691 tape->chrdev_direction = idetape_direction_none;
2696 if (tape->restart_speed_control_req)
2697 idetape_restart_speed_control(drive);
2698 idetape_init_rq(&rq, REQ_IDETAPE_READ);
2699 rq.sector = tape->first_frame_position;
2700 rq.nr_sectors = rq.current_nr_sectors = blocks;
2701 if (!test_bit(IDETAPE_PIPELINE_ERROR, &tape->flags) &&
2702 tape->nr_stages < max_stages) {
2703 new_stage = idetape_kmalloc_stage(tape);
2704 while (new_stage != NULL) {
2706 idetape_add_stage_tail(drive, new_stage);
2707 if (tape->nr_stages >= max_stages)
2709 new_stage = idetape_kmalloc_stage(tape);
2712 if (!idetape_pipeline_active(tape)) {
2713 if (tape->nr_pending_stages >= 3 * max_stages / 4) {
2714 tape->measure_insert_time = 1;
2715 tape->insert_time = jiffies;
2716 tape->insert_size = 0;
2717 tape->insert_speed = 0;
2718 idetape_insert_pipeline_into_queue(drive);
2725 * idetape_add_chrdev_read_request is called from idetape_chrdev_read
2726 * to service a character device read request and add read-ahead
2727 * requests to our pipeline.
2729 static int idetape_add_chrdev_read_request (ide_drive_t *drive,int blocks)
2731 idetape_tape_t *tape = drive->driver_data;
2732 unsigned long flags;
2733 struct request *rq_ptr;
2736 #if IDETAPE_DEBUG_LOG
2737 if (tape->debug_level >= 4)
2738 printk(KERN_INFO "ide-tape: Reached idetape_add_chrdev_read_request, %d blocks\n", blocks);
2739 #endif /* IDETAPE_DEBUG_LOG */
2742 * If we are at a filemark, return a read length of 0
2744 if (test_bit(IDETAPE_FILEMARK, &tape->flags))
2748 * Wait for the next block to be available at the head
2751 idetape_initiate_read(drive, tape->max_stages);
2752 if (tape->first_stage == NULL) {
2753 if (test_bit(IDETAPE_PIPELINE_ERROR, &tape->flags))
2755 return idetape_queue_rw_tail(drive, REQ_IDETAPE_READ, blocks, tape->merge_stage->bh);
2757 idetape_wait_first_stage(drive);
2758 rq_ptr = &tape->first_stage->rq;
2759 bytes_read = tape->tape_block_size * (rq_ptr->nr_sectors - rq_ptr->current_nr_sectors);
2760 rq_ptr->nr_sectors = rq_ptr->current_nr_sectors = 0;
2763 if (rq_ptr->errors == IDETAPE_ERROR_EOD)
2766 idetape_switch_buffers(tape, tape->first_stage);
2767 if (rq_ptr->errors == IDETAPE_ERROR_FILEMARK)
2768 set_bit(IDETAPE_FILEMARK, &tape->flags);
2769 spin_lock_irqsave(&tape->spinlock, flags);
2770 idetape_remove_stage_head(drive);
2771 spin_unlock_irqrestore(&tape->spinlock, flags);
2772 tape->pipeline_head++;
2773 calculate_speeds(drive);
2775 if (bytes_read > blocks * tape->tape_block_size) {
2776 printk(KERN_ERR "ide-tape: bug: trying to return more bytes than requested\n");
2777 bytes_read = blocks * tape->tape_block_size;
2779 return (bytes_read);
2782 static void idetape_pad_zeros (ide_drive_t *drive, int bcount)
2784 idetape_tape_t *tape = drive->driver_data;
2785 struct idetape_bh *bh;
2791 bh = tape->merge_stage->bh;
2792 count = min(tape->stage_size, bcount);
2794 blocks = count / tape->tape_block_size;
2796 atomic_set(&bh->b_count, min(count, (unsigned int)bh->b_size));
2797 memset(bh->b_data, 0, atomic_read(&bh->b_count));
2798 count -= atomic_read(&bh->b_count);
2801 idetape_queue_rw_tail(drive, REQ_IDETAPE_WRITE, blocks, tape->merge_stage->bh);
2805 static int idetape_pipeline_size (ide_drive_t *drive)
2807 idetape_tape_t *tape = drive->driver_data;
2808 idetape_stage_t *stage;
2812 idetape_wait_for_pipeline(drive);
2813 stage = tape->first_stage;
2814 while (stage != NULL) {
2816 size += tape->tape_block_size * (rq->nr_sectors-rq->current_nr_sectors);
2817 if (rq->errors == IDETAPE_ERROR_FILEMARK)
2818 size += tape->tape_block_size;
2819 stage = stage->next;
2821 size += tape->merge_stage_size;
2826 * Rewinds the tape to the Beginning Of the current Partition (BOP).
2828 * We currently support only one partition.
2830 static int idetape_rewind_tape (ide_drive_t *drive)
2834 #if IDETAPE_DEBUG_LOG
2835 idetape_tape_t *tape = drive->driver_data;
2836 if (tape->debug_level >= 2)
2837 printk(KERN_INFO "ide-tape: Reached idetape_rewind_tape\n");
2838 #endif /* IDETAPE_DEBUG_LOG */
2840 idetape_create_rewind_cmd(drive, &pc);
2841 retval = idetape_queue_pc_tail(drive, &pc);
2845 idetape_create_read_position_cmd(&pc);
2846 retval = idetape_queue_pc_tail(drive, &pc);
2853 * Our special ide-tape ioctl's.
2855 * Currently there aren't any ioctl's.
2856 * mtio.h compatible commands should be issued to the character device
2859 static int idetape_blkdev_ioctl(ide_drive_t *drive, unsigned int cmd, unsigned long arg)
2861 idetape_tape_t *tape = drive->driver_data;
2862 idetape_config_t config;
2863 void __user *argp = (void __user *)arg;
2865 #if IDETAPE_DEBUG_LOG
2866 if (tape->debug_level >= 4)
2867 printk(KERN_INFO "ide-tape: Reached idetape_blkdev_ioctl\n");
2868 #endif /* IDETAPE_DEBUG_LOG */
2871 if (copy_from_user(&config, argp, sizeof (idetape_config_t)))
2873 tape->best_dsc_rw_frequency = config.dsc_rw_frequency;
2874 tape->max_stages = config.nr_stages;
2877 config.dsc_rw_frequency = (int) tape->best_dsc_rw_frequency;
2878 config.nr_stages = tape->max_stages;
2879 if (copy_to_user(argp, &config, sizeof (idetape_config_t)))
2889 * idetape_space_over_filemarks is now a bit more complicated than just
2890 * passing the command to the tape since we may have crossed some
2891 * filemarks during our pipelined read-ahead mode.
2893 * As a minor side effect, the pipeline enables us to support MTFSFM when
2894 * the filemark is in our internal pipeline even if the tape doesn't
2895 * support spacing over filemarks in the reverse direction.
2897 static int idetape_space_over_filemarks (ide_drive_t *drive,short mt_op,int mt_count)
2899 idetape_tape_t *tape = drive->driver_data;
2901 unsigned long flags;
2903 int sprev = !!(tape->caps[4] & 0x20);
2907 if (MTBSF == mt_op || MTBSFM == mt_op) {
2910 mt_count = - mt_count;
2913 if (tape->chrdev_direction == idetape_direction_read) {
2915 * We have a read-ahead buffer. Scan it for crossed
2918 tape->merge_stage_size = 0;
2919 if (test_and_clear_bit(IDETAPE_FILEMARK, &tape->flags))
2921 while (tape->first_stage != NULL) {
2922 if (count == mt_count) {
2923 if (mt_op == MTFSFM)
2924 set_bit(IDETAPE_FILEMARK, &tape->flags);
2927 spin_lock_irqsave(&tape->spinlock, flags);
2928 if (tape->first_stage == tape->active_stage) {
2930 * We have reached the active stage in the read pipeline.
2931 * There is no point in allowing the drive to continue
2932 * reading any farther, so we stop the pipeline.
2934 * This section should be moved to a separate subroutine,
2935 * because a similar function is performed in
2936 * __idetape_discard_read_pipeline(), for example.
2938 tape->next_stage = NULL;
2939 spin_unlock_irqrestore(&tape->spinlock, flags);
2940 idetape_wait_first_stage(drive);
2941 tape->next_stage = tape->first_stage->next;
2943 spin_unlock_irqrestore(&tape->spinlock, flags);
2944 if (tape->first_stage->rq.errors == IDETAPE_ERROR_FILEMARK)
2946 idetape_remove_stage_head(drive);
2948 idetape_discard_read_pipeline(drive, 0);
2952 * The filemark was not found in our internal pipeline.
2953 * Now we can issue the space command.
2958 idetape_create_space_cmd(&pc,mt_count-count,IDETAPE_SPACE_OVER_FILEMARK);
2959 return (idetape_queue_pc_tail(drive, &pc));
2964 retval = idetape_space_over_filemarks(drive, MTFSF, mt_count-count);
2965 if (retval) return (retval);
2966 count = (MTBSFM == mt_op ? 1 : -1);
2967 return (idetape_space_over_filemarks(drive, MTFSF, count));
2969 printk(KERN_ERR "ide-tape: MTIO operation %d not supported\n",mt_op);
2976 * Our character device read / write functions.
2978 * The tape is optimized to maximize throughput when it is transferring
2979 * an integral number of the "continuous transfer limit", which is
2980 * a parameter of the specific tape (26 KB on my particular tape).
2981 * (32 kB for Onstream)
2983 * As of version 1.3 of the driver, the character device provides an
2984 * abstract continuous view of the media - any mix of block sizes (even 1
2985 * byte) on the same backup/restore procedure is supported. The driver
2986 * will internally convert the requests to the recommended transfer unit,
2987 * so that an unmatch between the user's block size to the recommended
2988 * size will only result in a (slightly) increased driver overhead, but
2989 * will no longer hit performance.
2990 * This is not applicable to Onstream.
2992 static ssize_t idetape_chrdev_read (struct file *file, char __user *buf,
2993 size_t count, loff_t *ppos)
2995 struct ide_tape_obj *tape = ide_tape_f(file);
2996 ide_drive_t *drive = tape->drive;
2997 ssize_t bytes_read,temp, actually_read = 0, rc;
2999 u16 ctl = *(u16 *)&tape->caps[12];
3001 #if IDETAPE_DEBUG_LOG
3002 if (tape->debug_level >= 3)
3003 printk(KERN_INFO "ide-tape: Reached idetape_chrdev_read, count %Zd\n", count);
3004 #endif /* IDETAPE_DEBUG_LOG */
3006 if (tape->chrdev_direction != idetape_direction_read) {
3007 if (test_bit(IDETAPE_DETECT_BS, &tape->flags))
3008 if (count > tape->tape_block_size &&
3009 (count % tape->tape_block_size) == 0)
3010 tape->user_bs_factor = count / tape->tape_block_size;
3012 if ((rc = idetape_initiate_read(drive, tape->max_stages)) < 0)
3016 if (tape->merge_stage_size) {
3017 actually_read = min((unsigned int)(tape->merge_stage_size), (unsigned int)count);
3018 if (idetape_copy_stage_to_user(tape, buf, tape->merge_stage, actually_read))
3020 buf += actually_read;
3021 tape->merge_stage_size -= actually_read;
3022 count -= actually_read;
3024 while (count >= tape->stage_size) {
3025 bytes_read = idetape_add_chrdev_read_request(drive, ctl);
3026 if (bytes_read <= 0)
3028 if (idetape_copy_stage_to_user(tape, buf, tape->merge_stage, bytes_read))
3031 count -= bytes_read;
3032 actually_read += bytes_read;
3035 bytes_read = idetape_add_chrdev_read_request(drive, ctl);
3036 if (bytes_read <= 0)
3038 temp = min((unsigned long)count, (unsigned long)bytes_read);
3039 if (idetape_copy_stage_to_user(tape, buf, tape->merge_stage, temp))
3041 actually_read += temp;
3042 tape->merge_stage_size = bytes_read-temp;
3045 if (!actually_read && test_bit(IDETAPE_FILEMARK, &tape->flags)) {
3046 #if IDETAPE_DEBUG_LOG
3047 if (tape->debug_level >= 2)
3048 printk(KERN_INFO "ide-tape: %s: spacing over filemark\n", tape->name);
3050 idetape_space_over_filemarks(drive, MTFSF, 1);
3054 return (ret) ? ret : actually_read;
3057 static ssize_t idetape_chrdev_write (struct file *file, const char __user *buf,
3058 size_t count, loff_t *ppos)
3060 struct ide_tape_obj *tape = ide_tape_f(file);
3061 ide_drive_t *drive = tape->drive;
3062 ssize_t actually_written = 0;
3064 u16 ctl = *(u16 *)&tape->caps[12];
3066 /* The drive is write protected. */
3067 if (tape->write_prot)
3070 #if IDETAPE_DEBUG_LOG
3071 if (tape->debug_level >= 3)
3072 printk(KERN_INFO "ide-tape: Reached idetape_chrdev_write, "
3073 "count %Zd\n", count);
3074 #endif /* IDETAPE_DEBUG_LOG */
3076 /* Initialize write operation */
3077 if (tape->chrdev_direction != idetape_direction_write) {
3078 if (tape->chrdev_direction == idetape_direction_read)
3079 idetape_discard_read_pipeline(drive, 1);
3080 if (tape->merge_stage || tape->merge_stage_size) {
3081 printk(KERN_ERR "ide-tape: merge_stage_size "
3082 "should be 0 now\n");
3083 tape->merge_stage_size = 0;
3085 if ((tape->merge_stage = __idetape_kmalloc_stage(tape, 0, 0)) == NULL)
3087 tape->chrdev_direction = idetape_direction_write;
3088 idetape_init_merge_stage(tape);
3091 * Issue a write 0 command to ensure that DSC handshake
3092 * is switched from completion mode to buffer available
3094 * No point in issuing this if DSC overlap isn't supported,
3095 * some drives (Seagate STT3401A) will return an error.
3097 if (drive->dsc_overlap) {
3098 ssize_t retval = idetape_queue_rw_tail(drive, REQ_IDETAPE_WRITE, 0, tape->merge_stage->bh);
3100 __idetape_kfree_stage(tape->merge_stage);
3101 tape->merge_stage = NULL;
3102 tape->chrdev_direction = idetape_direction_none;
3109 if (tape->restart_speed_control_req)
3110 idetape_restart_speed_control(drive);
3111 if (tape->merge_stage_size) {
3112 if (tape->merge_stage_size >= tape->stage_size) {
3113 printk(KERN_ERR "ide-tape: bug: merge buffer too big\n");
3114 tape->merge_stage_size = 0;
3116 actually_written = min((unsigned int)(tape->stage_size - tape->merge_stage_size), (unsigned int)count);
3117 if (idetape_copy_stage_from_user(tape, tape->merge_stage, buf, actually_written))
3119 buf += actually_written;
3120 tape->merge_stage_size += actually_written;
3121 count -= actually_written;
3123 if (tape->merge_stage_size == tape->stage_size) {
3125 tape->merge_stage_size = 0;
3126 retval = idetape_add_chrdev_write_request(drive, ctl);
3131 while (count >= tape->stage_size) {
3133 if (idetape_copy_stage_from_user(tape, tape->merge_stage, buf, tape->stage_size))
3135 buf += tape->stage_size;
3136 count -= tape->stage_size;
3137 retval = idetape_add_chrdev_write_request(drive, ctl);
3138 actually_written += tape->stage_size;
3143 actually_written += count;
3144 if (idetape_copy_stage_from_user(tape, tape->merge_stage, buf, count))
3146 tape->merge_stage_size += count;
3148 return (ret) ? ret : actually_written;
3151 static int idetape_write_filemark (ide_drive_t *drive)
3155 /* Write a filemark */
3156 idetape_create_write_filemark_cmd(drive, &pc, 1);
3157 if (idetape_queue_pc_tail(drive, &pc)) {
3158 printk(KERN_ERR "ide-tape: Couldn't write a filemark\n");
3165 * idetape_mtioctop is called from idetape_chrdev_ioctl when
3166 * the general mtio MTIOCTOP ioctl is requested.
3168 * We currently support the following mtio.h operations:
3170 * MTFSF - Space over mt_count filemarks in the positive direction.
3171 * The tape is positioned after the last spaced filemark.
3173 * MTFSFM - Same as MTFSF, but the tape is positioned before the
3176 * MTBSF - Steps background over mt_count filemarks, tape is
3177 * positioned before the last filemark.
3179 * MTBSFM - Like MTBSF, only tape is positioned after the last filemark.
3183 * MTBSF and MTBSFM are not supported when the tape doesn't
3184 * support spacing over filemarks in the reverse direction.
3185 * In this case, MTFSFM is also usually not supported (it is
3186 * supported in the rare case in which we crossed the filemark
3187 * during our read-ahead pipelined operation mode).
3189 * MTWEOF - Writes mt_count filemarks. Tape is positioned after
3190 * the last written filemark.
3192 * MTREW - Rewinds tape.
3194 * MTLOAD - Loads the tape.
3196 * MTOFFL - Puts the tape drive "Offline": Rewinds the tape and
3197 * MTUNLOAD prevents further access until the media is replaced.
3199 * MTNOP - Flushes tape buffers.
3201 * MTRETEN - Retension media. This typically consists of one end
3202 * to end pass on the media.
3204 * MTEOM - Moves to the end of recorded data.
3206 * MTERASE - Erases tape.
3208 * MTSETBLK - Sets the user block size to mt_count bytes. If
3209 * mt_count is 0, we will attempt to autodetect
3212 * MTSEEK - Positions the tape in a specific block number, where
3213 * each block is assumed to contain which user_block_size
3216 * MTSETPART - Switches to another tape partition.
3218 * MTLOCK - Locks the tape door.
3220 * MTUNLOCK - Unlocks the tape door.
3222 * The following commands are currently not supported:
3224 * MTFSS, MTBSS, MTWSM, MTSETDENSITY,
3225 * MTSETDRVBUFFER, MT_ST_BOOLEANS, MT_ST_WRITE_THRESHOLD.
3227 static int idetape_mtioctop (ide_drive_t *drive,short mt_op,int mt_count)
3229 idetape_tape_t *tape = drive->driver_data;
3233 #if IDETAPE_DEBUG_LOG
3234 if (tape->debug_level >= 1)
3235 printk(KERN_INFO "ide-tape: Handling MTIOCTOP ioctl: "
3236 "mt_op=%d, mt_count=%d\n", mt_op, mt_count);
3237 #endif /* IDETAPE_DEBUG_LOG */
3239 * Commands which need our pipelined read-ahead stages.
3248 return (idetape_space_over_filemarks(drive,mt_op,mt_count));
3254 if (tape->write_prot)
3256 idetape_discard_read_pipeline(drive, 1);
3257 for (i = 0; i < mt_count; i++) {
3258 retval = idetape_write_filemark(drive);
3264 idetape_discard_read_pipeline(drive, 0);
3265 if (idetape_rewind_tape(drive))
3269 idetape_discard_read_pipeline(drive, 0);
3270 idetape_create_load_unload_cmd(drive, &pc, IDETAPE_LU_LOAD_MASK);
3271 return (idetape_queue_pc_tail(drive, &pc));
3275 * If door is locked, attempt to unlock before
3276 * attempting to eject.
3278 if (tape->door_locked) {
3279 if (idetape_create_prevent_cmd(drive, &pc, 0))
3280 if (!idetape_queue_pc_tail(drive, &pc))
3281 tape->door_locked = DOOR_UNLOCKED;
3283 idetape_discard_read_pipeline(drive, 0);
3284 idetape_create_load_unload_cmd(drive, &pc,!IDETAPE_LU_LOAD_MASK);
3285 retval = idetape_queue_pc_tail(drive, &pc);
3287 clear_bit(IDETAPE_MEDIUM_PRESENT, &tape->flags);
3290 idetape_discard_read_pipeline(drive, 0);
3291 return (idetape_flush_tape_buffers(drive));
3293 idetape_discard_read_pipeline(drive, 0);
3294 idetape_create_load_unload_cmd(drive, &pc,IDETAPE_LU_RETENSION_MASK | IDETAPE_LU_LOAD_MASK);
3295 return (idetape_queue_pc_tail(drive, &pc));
3297 idetape_create_space_cmd(&pc, 0, IDETAPE_SPACE_TO_EOD);
3298 return (idetape_queue_pc_tail(drive, &pc));
3300 (void) idetape_rewind_tape(drive);
3301 idetape_create_erase_cmd(&pc);
3302 return (idetape_queue_pc_tail(drive, &pc));
3305 if (mt_count < tape->tape_block_size || mt_count % tape->tape_block_size)
3307 tape->user_bs_factor = mt_count / tape->tape_block_size;
3308 clear_bit(IDETAPE_DETECT_BS, &tape->flags);
3310 set_bit(IDETAPE_DETECT_BS, &tape->flags);
3313 idetape_discard_read_pipeline(drive, 0);
3314 return idetape_position_tape(drive, mt_count * tape->user_bs_factor, tape->partition, 0);
3316 idetape_discard_read_pipeline(drive, 0);
3317 return (idetape_position_tape(drive, 0, mt_count, 0));
3321 if (!idetape_create_prevent_cmd(drive, &pc, 1))
3323 retval = idetape_queue_pc_tail(drive, &pc);
3324 if (retval) return retval;
3325 tape->door_locked = DOOR_EXPLICITLY_LOCKED;
3328 if (!idetape_create_prevent_cmd(drive, &pc, 0))
3330 retval = idetape_queue_pc_tail(drive, &pc);
3331 if (retval) return retval;
3332 tape->door_locked = DOOR_UNLOCKED;
3335 printk(KERN_ERR "ide-tape: MTIO operation %d not "
3336 "supported\n", mt_op);
3342 * Our character device ioctls.
3344 * General mtio.h magnetic io commands are supported here, and not in
3345 * the corresponding block interface.
3347 * The following ioctls are supported:
3349 * MTIOCTOP - Refer to idetape_mtioctop for detailed description.
3351 * MTIOCGET - The mt_dsreg field in the returned mtget structure
3352 * will be set to (user block size in bytes <<
3353 * MT_ST_BLKSIZE_SHIFT) & MT_ST_BLKSIZE_MASK.
3355 * The mt_blkno is set to the current user block number.
3356 * The other mtget fields are not supported.
3358 * MTIOCPOS - The current tape "block position" is returned. We
3359 * assume that each block contains user_block_size
3362 * Our own ide-tape ioctls are supported on both interfaces.
3364 static int idetape_chrdev_ioctl (struct inode *inode, struct file *file, unsigned int cmd, unsigned long arg)
3366 struct ide_tape_obj *tape = ide_tape_f(file);
3367 ide_drive_t *drive = tape->drive;
3371 int block_offset = 0, position = tape->first_frame_position;
3372 void __user *argp = (void __user *)arg;
3374 #if IDETAPE_DEBUG_LOG
3375 if (tape->debug_level >= 3)
3376 printk(KERN_INFO "ide-tape: Reached idetape_chrdev_ioctl, "
3378 #endif /* IDETAPE_DEBUG_LOG */
3380 tape->restart_speed_control_req = 1;
3381 if (tape->chrdev_direction == idetape_direction_write) {
3382 idetape_empty_write_pipeline(drive);
3383 idetape_flush_tape_buffers(drive);
3385 if (cmd == MTIOCGET || cmd == MTIOCPOS) {
3386 block_offset = idetape_pipeline_size(drive) / (tape->tape_block_size * tape->user_bs_factor);
3387 if ((position = idetape_read_position(drive)) < 0)
3392 if (copy_from_user(&mtop, argp, sizeof (struct mtop)))
3394 return (idetape_mtioctop(drive,mtop.mt_op,mtop.mt_count));
3396 memset(&mtget, 0, sizeof (struct mtget));
3397 mtget.mt_type = MT_ISSCSI2;
3398 mtget.mt_blkno = position / tape->user_bs_factor - block_offset;
3399 mtget.mt_dsreg = ((tape->tape_block_size * tape->user_bs_factor) << MT_ST_BLKSIZE_SHIFT) & MT_ST_BLKSIZE_MASK;
3400 if (tape->drv_write_prot) {
3401 mtget.mt_gstat |= GMT_WR_PROT(0xffffffff);
3403 if (copy_to_user(argp, &mtget, sizeof(struct mtget)))
3407 mtpos.mt_blkno = position / tape->user_bs_factor - block_offset;
3408 if (copy_to_user(argp, &mtpos, sizeof(struct mtpos)))
3412 if (tape->chrdev_direction == idetape_direction_read)
3413 idetape_discard_read_pipeline(drive, 1);
3414 return idetape_blkdev_ioctl(drive, cmd, arg);
3419 * Do a mode sense page 0 with block descriptor and if it succeeds set the tape
3420 * block size with the reported value.
3422 static void ide_tape_get_bsize_from_bdesc(ide_drive_t *drive)
3424 idetape_tape_t *tape = drive->driver_data;
3427 idetape_create_mode_sense_cmd(&pc, IDETAPE_BLOCK_DESCRIPTOR);
3428 if (idetape_queue_pc_tail(drive, &pc)) {
3429 printk(KERN_ERR "ide-tape: Can't get block descriptor\n");
3430 if (tape->tape_block_size == 0) {
3431 printk(KERN_WARNING "ide-tape: Cannot deal with zero "
3432 "block size, assuming 32k\n");
3433 tape->tape_block_size = 32768;
3437 tape->tape_block_size = (pc.buffer[4 + 5] << 16) +
3438 (pc.buffer[4 + 6] << 8) +
3440 tape->drv_write_prot = (pc.buffer[2] & 0x80) >> 7;
3444 * Our character device open function.
3446 static int idetape_chrdev_open (struct inode *inode, struct file *filp)
3448 unsigned int minor = iminor(inode), i = minor & ~0xc0;
3450 idetape_tape_t *tape;
3455 * We really want to do nonseekable_open(inode, filp); here, but some
3456 * versions of tar incorrectly call lseek on tapes and bail out if that
3457 * fails. So we disallow pread() and pwrite(), but permit lseeks.
3459 filp->f_mode &= ~(FMODE_PREAD | FMODE_PWRITE);
3461 #if IDETAPE_DEBUG_LOG
3462 printk(KERN_INFO "ide-tape: Reached idetape_chrdev_open\n");
3463 #endif /* IDETAPE_DEBUG_LOG */
3465 if (i >= MAX_HWIFS * MAX_DRIVES)
3468 if (!(tape = ide_tape_chrdev_get(i)))
3471 drive = tape->drive;
3473 filp->private_data = tape;
3475 if (test_and_set_bit(IDETAPE_BUSY, &tape->flags)) {
3480 retval = idetape_wait_ready(drive, 60 * HZ);
3482 clear_bit(IDETAPE_BUSY, &tape->flags);
3483 printk(KERN_ERR "ide-tape: %s: drive not ready\n", tape->name);
3487 idetape_read_position(drive);
3488 if (!test_bit(IDETAPE_ADDRESS_VALID, &tape->flags))
3489 (void)idetape_rewind_tape(drive);
3491 if (tape->chrdev_direction != idetape_direction_read)
3492 clear_bit(IDETAPE_PIPELINE_ERROR, &tape->flags);
3494 /* Read block size and write protect status from drive. */
3495 ide_tape_get_bsize_from_bdesc(drive);
3497 /* Set write protect flag if device is opened as read-only. */
3498 if ((filp->f_flags & O_ACCMODE) == O_RDONLY)
3499 tape->write_prot = 1;
3501 tape->write_prot = tape->drv_write_prot;
3503 /* Make sure drive isn't write protected if user wants to write. */
3504 if (tape->write_prot) {
3505 if ((filp->f_flags & O_ACCMODE) == O_WRONLY ||
3506 (filp->f_flags & O_ACCMODE) == O_RDWR) {
3507 clear_bit(IDETAPE_BUSY, &tape->flags);
3514 * Lock the tape drive door so user can't eject.
3516 if (tape->chrdev_direction == idetape_direction_none) {
3517 if (idetape_create_prevent_cmd(drive, &pc, 1)) {
3518 if (!idetape_queue_pc_tail(drive, &pc)) {
3519 if (tape->door_locked != DOOR_EXPLICITLY_LOCKED)
3520 tape->door_locked = DOOR_LOCKED;
3524 idetape_restart_speed_control(drive);
3525 tape->restart_speed_control_req = 0;
3533 static void idetape_write_release (ide_drive_t *drive, unsigned int minor)
3535 idetape_tape_t *tape = drive->driver_data;
3537 idetape_empty_write_pipeline(drive);
3538 tape->merge_stage = __idetape_kmalloc_stage(tape, 1, 0);
3539 if (tape->merge_stage != NULL) {
3540 idetape_pad_zeros(drive, tape->tape_block_size * (tape->user_bs_factor - 1));
3541 __idetape_kfree_stage(tape->merge_stage);
3542 tape->merge_stage = NULL;
3544 idetape_write_filemark(drive);
3545 idetape_flush_tape_buffers(drive);
3546 idetape_flush_tape_buffers(drive);
3550 * Our character device release function.
3552 static int idetape_chrdev_release (struct inode *inode, struct file *filp)
3554 struct ide_tape_obj *tape = ide_tape_f(filp);
3555 ide_drive_t *drive = tape->drive;
3557 unsigned int minor = iminor(inode);
3560 tape = drive->driver_data;
3561 #if IDETAPE_DEBUG_LOG
3562 if (tape->debug_level >= 3)
3563 printk(KERN_INFO "ide-tape: Reached idetape_chrdev_release\n");
3564 #endif /* IDETAPE_DEBUG_LOG */
3566 if (tape->chrdev_direction == idetape_direction_write)
3567 idetape_write_release(drive, minor);
3568 if (tape->chrdev_direction == idetape_direction_read) {
3570 idetape_discard_read_pipeline(drive, 1);
3572 idetape_wait_for_pipeline(drive);
3574 if (tape->cache_stage != NULL) {
3575 __idetape_kfree_stage(tape->cache_stage);
3576 tape->cache_stage = NULL;
3578 if (minor < 128 && test_bit(IDETAPE_MEDIUM_PRESENT, &tape->flags))
3579 (void) idetape_rewind_tape(drive);
3580 if (tape->chrdev_direction == idetape_direction_none) {
3581 if (tape->door_locked == DOOR_LOCKED) {
3582 if (idetape_create_prevent_cmd(drive, &pc, 0)) {
3583 if (!idetape_queue_pc_tail(drive, &pc))
3584 tape->door_locked = DOOR_UNLOCKED;
3588 clear_bit(IDETAPE_BUSY, &tape->flags);
3595 * idetape_identify_device is called to check the contents of the
3596 * ATAPI IDENTIFY command results. We return:
3598 * 1 If the tape can be supported by us, based on the information
3601 * 0 If this tape driver is not currently supported by us.
3603 static int idetape_identify_device (ide_drive_t *drive)
3605 struct idetape_id_gcw gcw;
3606 struct hd_driveid *id = drive->id;
3608 if (drive->id_read == 0)
3611 *((unsigned short *) &gcw) = id->config;
3613 /* Check that we can support this device */
3615 if (gcw.protocol != 2)
3616 printk(KERN_ERR "ide-tape: Protocol (0x%02x) is not ATAPI\n",
3618 else if (gcw.device_type != 1)
3619 printk(KERN_ERR "ide-tape: Device type (0x%02x) is not set "
3620 "to tape\n", gcw.device_type);
3621 else if (!gcw.removable)
3622 printk(KERN_ERR "ide-tape: The removable flag is not set\n");
3623 else if (gcw.packet_size != 0) {
3624 printk(KERN_ERR "ide-tape: Packet size (0x%02x) is not 12 "
3625 "bytes long\n", gcw.packet_size);
3631 static void idetape_get_inquiry_results(ide_drive_t *drive)
3634 idetape_tape_t *tape = drive->driver_data;
3637 idetape_create_inquiry_cmd(&pc);
3638 if (idetape_queue_pc_tail(drive, &pc)) {
3639 printk(KERN_ERR "ide-tape: %s: can't get INQUIRY results\n",
3643 memcpy(tape->vendor_id, &pc.buffer[8], 8);
3644 memcpy(tape->product_id, &pc.buffer[16], 16);
3645 memcpy(tape->firmware_revision, &pc.buffer[32], 4);
3647 ide_fixstring(tape->vendor_id, 10, 0);
3648 ide_fixstring(tape->product_id, 18, 0);
3649 ide_fixstring(tape->firmware_revision, 6, 0);
3650 r = tape->firmware_revision;
3651 if (*(r + 1) == '.')
3652 tape->firmware_revision_num = (*r - '0') * 100 +
3653 (*(r + 2) - '0') * 10 + *(r + 3) - '0';
3654 printk(KERN_INFO "ide-tape: %s <-> %s: %s %s rev %s\n",
3655 drive->name, tape->name, tape->vendor_id,
3656 tape->product_id, tape->firmware_revision);
3660 * Ask the tape about its various parameters. In particular, we will adjust our
3661 * data transfer buffer size to the recommended value as returned by the tape.
3663 static void idetape_get_mode_sense_results (ide_drive_t *drive)
3665 idetape_tape_t *tape = drive->driver_data;
3668 u8 speed, max_speed;
3670 idetape_create_mode_sense_cmd(&pc, IDETAPE_CAPABILITIES_PAGE);
3671 if (idetape_queue_pc_tail(drive, &pc)) {
3672 printk(KERN_ERR "ide-tape: Can't get tape parameters - assuming"
3673 " some default values\n");
3674 tape->tape_block_size = 512;
3675 put_unaligned(52, (u16 *)&tape->caps[12]);
3676 put_unaligned(540, (u16 *)&tape->caps[14]);
3677 put_unaligned(6*52, (u16 *)&tape->caps[16]);
3680 caps = pc.buffer + 4 + pc.buffer[3];
3682 /* convert to host order and save for later use */
3683 speed = be16_to_cpu(*(u16 *)&caps[14]);
3684 max_speed = be16_to_cpu(*(u16 *)&caps[8]);
3686 put_unaligned(max_speed, (u16 *)&caps[8]);
3687 put_unaligned(be16_to_cpu(*(u16 *)&caps[12]), (u16 *)&caps[12]);
3688 put_unaligned(speed, (u16 *)&caps[14]);
3689 put_unaligned(be16_to_cpu(*(u16 *)&caps[16]), (u16 *)&caps[16]);
3692 printk(KERN_INFO "ide-tape: %s: invalid tape speed "
3693 "(assuming 650KB/sec)\n", drive->name);
3694 put_unaligned(650, (u16 *)&caps[14]);
3697 printk(KERN_INFO "ide-tape: %s: invalid max_speed "
3698 "(assuming 650KB/sec)\n", drive->name);
3699 put_unaligned(650, (u16 *)&caps[8]);
3702 memcpy(&tape->caps, caps, 20);
3704 tape->tape_block_size = 512;
3705 else if (caps[7] & 0x04)
3706 tape->tape_block_size = 1024;
3709 #ifdef CONFIG_IDE_PROC_FS
3710 static void idetape_add_settings (ide_drive_t *drive)
3712 idetape_tape_t *tape = drive->driver_data;
3715 * drive setting name read/write data type min max mul_factor div_factor data pointer set function
3717 ide_add_setting(drive, "buffer", SETTING_READ, TYPE_SHORT, 0, 0xffff,
3718 1, 2, (u16 *)&tape->caps[16], NULL);
3719 ide_add_setting(drive, "pipeline_min", SETTING_RW, TYPE_INT, 1, 0xffff, tape->stage_size / 1024, 1, &tape->min_pipeline, NULL);
3720 ide_add_setting(drive, "pipeline", SETTING_RW, TYPE_INT, 1, 0xffff, tape->stage_size / 1024, 1, &tape->max_stages, NULL);
3721 ide_add_setting(drive, "pipeline_max", SETTING_RW, TYPE_INT, 1, 0xffff, tape->stage_size / 1024, 1, &tape->max_pipeline, NULL);
3722 ide_add_setting(drive, "pipeline_used", SETTING_READ, TYPE_INT, 0, 0xffff, tape->stage_size / 1024, 1, &tape->nr_stages, NULL);
3723 ide_add_setting(drive, "pipeline_pending", SETTING_READ, TYPE_INT, 0, 0xffff, tape->stage_size / 1024, 1, &tape->nr_pending_stages, NULL);
3724 ide_add_setting(drive, "speed", SETTING_READ, TYPE_SHORT, 0, 0xffff,
3725 1, 1, (u16 *)&tape->caps[14], NULL);
3726 ide_add_setting(drive, "stage", SETTING_READ, TYPE_INT, 0, 0xffff, 1, 1024, &tape->stage_size, NULL);
3727 ide_add_setting(drive, "tdsc", SETTING_RW, TYPE_INT, IDETAPE_DSC_RW_MIN, IDETAPE_DSC_RW_MAX, 1000, HZ, &tape->best_dsc_rw_frequency, NULL);
3728 ide_add_setting(drive, "dsc_overlap", SETTING_RW, TYPE_BYTE, 0, 1, 1, 1, &drive->dsc_overlap, NULL);
3729 ide_add_setting(drive, "pipeline_head_speed_c",SETTING_READ, TYPE_INT, 0, 0xffff, 1, 1, &tape->controlled_pipeline_head_speed, NULL);
3730 ide_add_setting(drive, "pipeline_head_speed_u",SETTING_READ, TYPE_INT, 0, 0xffff, 1, 1, &tape->uncontrolled_pipeline_head_speed,NULL);
3731 ide_add_setting(drive, "avg_speed", SETTING_READ, TYPE_INT, 0, 0xffff, 1, 1, &tape->avg_speed, NULL);
3732 ide_add_setting(drive, "debug_level", SETTING_RW, TYPE_INT, 0, 0xffff, 1, 1, &tape->debug_level, NULL);
3735 static inline void idetape_add_settings(ide_drive_t *drive) { ; }
3739 * ide_setup is called to:
3741 * 1. Initialize our various state variables.
3742 * 2. Ask the tape for its capabilities.
3743 * 3. Allocate a buffer which will be used for data
3744 * transfer. The buffer size is chosen based on
3745 * the recommendation which we received in step (2).
3747 * Note that at this point ide.c already assigned us an irq, so that
3748 * we can queue requests here and wait for their completion.
3750 static void idetape_setup (ide_drive_t *drive, idetape_tape_t *tape, int minor)
3752 unsigned long t1, tmid, tn, t;
3754 struct idetape_id_gcw gcw;
3757 u16 *ctl = (u16 *)&tape->caps[12];
3759 spin_lock_init(&tape->spinlock);
3760 drive->dsc_overlap = 1;
3761 if (drive->hwif->host_flags & IDE_HFLAG_NO_DSC) {
3762 printk(KERN_INFO "ide-tape: %s: disabling DSC overlap\n",
3764 drive->dsc_overlap = 0;
3766 /* Seagate Travan drives do not support DSC overlap. */
3767 if (strstr(drive->id->model, "Seagate STT3401"))
3768 drive->dsc_overlap = 0;
3769 tape->minor = minor;
3770 tape->name[0] = 'h';
3771 tape->name[1] = 't';
3772 tape->name[2] = '0' + minor;
3773 tape->chrdev_direction = idetape_direction_none;
3774 tape->pc = tape->pc_stack;
3775 tape->max_insert_speed = 10000;
3776 tape->speed_control = 1;
3777 *((unsigned short *) &gcw) = drive->id->config;
3778 if (gcw.drq_type == 1)
3779 set_bit(IDETAPE_DRQ_INTERRUPT, &tape->flags);
3781 tape->min_pipeline = tape->max_pipeline = tape->max_stages = 10;
3783 idetape_get_inquiry_results(drive);
3784 idetape_get_mode_sense_results(drive);
3785 ide_tape_get_bsize_from_bdesc(drive);
3786 tape->user_bs_factor = 1;
3787 tape->stage_size = *ctl * tape->tape_block_size;
3788 while (tape->stage_size > 0xffff) {
3789 printk(KERN_NOTICE "ide-tape: decreasing stage size\n");
3791 tape->stage_size = *ctl * tape->tape_block_size;
3793 stage_size = tape->stage_size;
3794 tape->pages_per_stage = stage_size / PAGE_SIZE;
3795 if (stage_size % PAGE_SIZE) {
3796 tape->pages_per_stage++;
3797 tape->excess_bh_size = PAGE_SIZE - stage_size % PAGE_SIZE;
3800 /* Select the "best" DSC read/write polling freq and pipeline size. */
3801 speed = max(*(u16 *)&tape->caps[14], *(u16 *)&tape->caps[8]);
3803 tape->max_stages = speed * 1000 * 10 / tape->stage_size;
3806 * Limit memory use for pipeline to 10% of physical memory
3809 if (tape->max_stages * tape->stage_size > si.totalram * si.mem_unit / 10)
3810 tape->max_stages = si.totalram * si.mem_unit / (10 * tape->stage_size);
3811 tape->max_stages = min(tape->max_stages, IDETAPE_MAX_PIPELINE_STAGES);
3812 tape->min_pipeline = min(tape->max_stages, IDETAPE_MIN_PIPELINE_STAGES);
3813 tape->max_pipeline = min(tape->max_stages * 2, IDETAPE_MAX_PIPELINE_STAGES);
3814 if (tape->max_stages == 0)
3815 tape->max_stages = tape->min_pipeline = tape->max_pipeline = 1;
3817 t1 = (tape->stage_size * HZ) / (speed * 1000);
3818 tmid = (*(u16 *)&tape->caps[16] * 32 * HZ) / (speed * 125);
3819 tn = (IDETAPE_FIFO_THRESHOLD * tape->stage_size * HZ) / (speed * 1000);
3821 if (tape->max_stages)
3827 * Ensure that the number we got makes sense; limit
3828 * it within IDETAPE_DSC_RW_MIN and IDETAPE_DSC_RW_MAX.
3830 tape->best_dsc_rw_frequency = max_t(unsigned long, min_t(unsigned long, t, IDETAPE_DSC_RW_MAX), IDETAPE_DSC_RW_MIN);
3831 printk(KERN_INFO "ide-tape: %s <-> %s: %dKBps, %d*%dkB buffer, "
3832 "%dkB pipeline, %lums tDSC%s\n",
3833 drive->name, tape->name, *(u16 *)&tape->caps[14],
3834 (*(u16 *)&tape->caps[16] * 512) / tape->stage_size,
3835 tape->stage_size / 1024,
3836 tape->max_stages * tape->stage_size / 1024,
3837 tape->best_dsc_rw_frequency * 1000 / HZ,
3838 drive->using_dma ? ", DMA":"");
3840 idetape_add_settings(drive);
3843 static void ide_tape_remove(ide_drive_t *drive)
3845 idetape_tape_t *tape = drive->driver_data;
3847 ide_proc_unregister_driver(drive, tape->driver);
3849 ide_unregister_region(tape->disk);
3854 static void ide_tape_release(struct kref *kref)
3856 struct ide_tape_obj *tape = to_ide_tape(kref);
3857 ide_drive_t *drive = tape->drive;
3858 struct gendisk *g = tape->disk;
3860 BUG_ON(tape->first_stage != NULL || tape->merge_stage_size);
3862 drive->dsc_overlap = 0;
3863 drive->driver_data = NULL;
3864 device_destroy(idetape_sysfs_class, MKDEV(IDETAPE_MAJOR, tape->minor));
3865 device_destroy(idetape_sysfs_class, MKDEV(IDETAPE_MAJOR, tape->minor + 128));
3866 idetape_devs[tape->minor] = NULL;
3867 g->private_data = NULL;
3872 #ifdef CONFIG_IDE_PROC_FS
3873 static int proc_idetape_read_name
3874 (char *page, char **start, off_t off, int count, int *eof, void *data)
3876 ide_drive_t *drive = (ide_drive_t *) data;
3877 idetape_tape_t *tape = drive->driver_data;
3881 len = sprintf(out, "%s\n", tape->name);
3882 PROC_IDE_READ_RETURN(page, start, off, count, eof, len);
3885 static ide_proc_entry_t idetape_proc[] = {
3886 { "capacity", S_IFREG|S_IRUGO, proc_ide_read_capacity, NULL },
3887 { "name", S_IFREG|S_IRUGO, proc_idetape_read_name, NULL },
3888 { NULL, 0, NULL, NULL }
3892 static int ide_tape_probe(ide_drive_t *);
3894 static ide_driver_t idetape_driver = {
3896 .owner = THIS_MODULE,
3898 .bus = &ide_bus_type,
3900 .probe = ide_tape_probe,
3901 .remove = ide_tape_remove,
3902 .version = IDETAPE_VERSION,
3904 .supports_dsc_overlap = 1,
3905 .do_request = idetape_do_request,
3906 .end_request = idetape_end_request,
3907 .error = __ide_error,
3908 .abort = __ide_abort,
3909 #ifdef CONFIG_IDE_PROC_FS
3910 .proc = idetape_proc,
3915 * Our character device supporting functions, passed to register_chrdev.
3917 static const struct file_operations idetape_fops = {
3918 .owner = THIS_MODULE,
3919 .read = idetape_chrdev_read,
3920 .write = idetape_chrdev_write,
3921 .ioctl = idetape_chrdev_ioctl,
3922 .open = idetape_chrdev_open,
3923 .release = idetape_chrdev_release,
3926 static int idetape_open(struct inode *inode, struct file *filp)
3928 struct gendisk *disk = inode->i_bdev->bd_disk;
3929 struct ide_tape_obj *tape;
3931 if (!(tape = ide_tape_get(disk)))
3937 static int idetape_release(struct inode *inode, struct file *filp)
3939 struct gendisk *disk = inode->i_bdev->bd_disk;
3940 struct ide_tape_obj *tape = ide_tape_g(disk);
3947 static int idetape_ioctl(struct inode *inode, struct file *file,
3948 unsigned int cmd, unsigned long arg)
3950 struct block_device *bdev = inode->i_bdev;
3951 struct ide_tape_obj *tape = ide_tape_g(bdev->bd_disk);
3952 ide_drive_t *drive = tape->drive;
3953 int err = generic_ide_ioctl(drive, file, bdev, cmd, arg);
3955 err = idetape_blkdev_ioctl(drive, cmd, arg);
3959 static struct block_device_operations idetape_block_ops = {
3960 .owner = THIS_MODULE,
3961 .open = idetape_open,
3962 .release = idetape_release,
3963 .ioctl = idetape_ioctl,
3966 static int ide_tape_probe(ide_drive_t *drive)
3968 idetape_tape_t *tape;
3972 if (!strstr("ide-tape", drive->driver_req))
3974 if (!drive->present)
3976 if (drive->media != ide_tape)
3978 if (!idetape_identify_device (drive)) {
3979 printk(KERN_ERR "ide-tape: %s: not supported by this version of ide-tape\n", drive->name);
3983 printk("ide-tape: passing drive %s to ide-scsi emulation.\n", drive->name);
3986 if (strstr(drive->id->model, "OnStream DI-")) {
3987 printk(KERN_WARNING "ide-tape: Use drive %s with ide-scsi emulation and osst.\n", drive->name);
3988 printk(KERN_WARNING "ide-tape: OnStream support will be removed soon from ide-tape!\n");
3990 tape = kzalloc(sizeof (idetape_tape_t), GFP_KERNEL);
3992 printk(KERN_ERR "ide-tape: %s: Can't allocate a tape structure\n", drive->name);
3996 g = alloc_disk(1 << PARTN_BITS);
4000 ide_init_disk(g, drive);
4002 ide_proc_register_driver(drive, &idetape_driver);
4004 kref_init(&tape->kref);
4006 tape->drive = drive;
4007 tape->driver = &idetape_driver;
4010 g->private_data = &tape->driver;
4012 drive->driver_data = tape;
4014 mutex_lock(&idetape_ref_mutex);
4015 for (minor = 0; idetape_devs[minor]; minor++)
4017 idetape_devs[minor] = tape;
4018 mutex_unlock(&idetape_ref_mutex);
4020 idetape_setup(drive, tape, minor);
4022 device_create(idetape_sysfs_class, &drive->gendev,
4023 MKDEV(IDETAPE_MAJOR, minor), "%s", tape->name);
4024 device_create(idetape_sysfs_class, &drive->gendev,
4025 MKDEV(IDETAPE_MAJOR, minor + 128), "n%s", tape->name);
4027 g->fops = &idetape_block_ops;
4028 ide_register_region(g);
4038 MODULE_DESCRIPTION("ATAPI Streaming TAPE Driver");
4039 MODULE_LICENSE("GPL");
4041 static void __exit idetape_exit (void)
4043 driver_unregister(&idetape_driver.gen_driver);
4044 class_destroy(idetape_sysfs_class);
4045 unregister_chrdev(IDETAPE_MAJOR, "ht");
4048 static int __init idetape_init(void)
4051 idetape_sysfs_class = class_create(THIS_MODULE, "ide_tape");
4052 if (IS_ERR(idetape_sysfs_class)) {
4053 idetape_sysfs_class = NULL;
4054 printk(KERN_ERR "Unable to create sysfs class for ide tapes\n");
4059 if (register_chrdev(IDETAPE_MAJOR, "ht", &idetape_fops)) {
4060 printk(KERN_ERR "ide-tape: Failed to register character device interface\n");
4062 goto out_free_class;
4065 error = driver_register(&idetape_driver.gen_driver);
4067 goto out_free_driver;
4072 driver_unregister(&idetape_driver.gen_driver);
4074 class_destroy(idetape_sysfs_class);
4079 MODULE_ALIAS("ide:*m-tape*");
4080 module_init(idetape_init);
4081 module_exit(idetape_exit);
4082 MODULE_ALIAS_CHARDEV_MAJOR(IDETAPE_MAJOR);