ia64/linux-2.6.18-xen.hg

view drivers/ide/ide-tape.c @ 893:f994bfe9b93b

linux/blktap2: reduce TLB flush scope

c/s 885 added very coarse TLB flushing. Since these flushes always
follow single page updates, single page flushes (when available) are
sufficient.

Signed-off-by: Jan Beulich <jbeulich@novell.com>
author Keir Fraser <keir.fraser@citrix.com>
date Thu Jun 04 10:32:57 2009 +0100 (2009-06-04)
parents 831230e53067
children
line source
1 /*
2 * linux/drivers/ide/ide-tape.c Version 1.19 Nov, 2003
3 *
4 * Copyright (C) 1995 - 1999 Gadi Oxman <gadio@netvision.net.il>
5 *
6 * $Header$
7 *
8 * This driver was constructed as a student project in the software laboratory
9 * of the faculty of electrical engineering in the Technion - Israel's
10 * Institute Of Technology, with the guide of Avner Lottem and Dr. Ilana David.
11 *
12 * It is hereby placed under the terms of the GNU general public license.
13 * (See linux/COPYING).
14 */
16 /*
17 * IDE ATAPI streaming tape driver.
18 *
19 * This driver is a part of the Linux ide driver and works in co-operation
20 * with linux/drivers/block/ide.c.
21 *
22 * The driver, in co-operation with ide.c, basically traverses the
23 * request-list for the block device interface. The character device
24 * interface, on the other hand, creates new requests, adds them
25 * to the request-list of the block device, and waits for their completion.
26 *
27 * Pipelined operation mode is now supported on both reads and writes.
28 *
29 * The block device major and minor numbers are determined from the
30 * tape's relative position in the ide interfaces, as explained in ide.c.
31 *
32 * The character device interface consists of the following devices:
33 *
34 * ht0 major 37, minor 0 first IDE tape, rewind on close.
35 * ht1 major 37, minor 1 second IDE tape, rewind on close.
36 * ...
37 * nht0 major 37, minor 128 first IDE tape, no rewind on close.
38 * nht1 major 37, minor 129 second IDE tape, no rewind on close.
39 * ...
40 *
41 * Run linux/scripts/MAKEDEV.ide to create the above entries.
42 *
43 * The general magnetic tape commands compatible interface, as defined by
44 * include/linux/mtio.h, is accessible through the character device.
45 *
46 * General ide driver configuration options, such as the interrupt-unmask
47 * flag, can be configured by issuing an ioctl to the block device interface,
48 * as any other ide device.
49 *
50 * Our own ide-tape ioctl's can be issued to either the block device or
51 * the character device interface.
52 *
53 * Maximal throughput with minimal bus load will usually be achieved in the
54 * following scenario:
55 *
56 * 1. ide-tape is operating in the pipelined operation mode.
57 * 2. No buffering is performed by the user backup program.
58 *
59 * Testing was done with a 2 GB CONNER CTMA 4000 IDE ATAPI Streaming Tape Drive.
60 *
61 * Ver 0.1 Nov 1 95 Pre-working code :-)
62 * Ver 0.2 Nov 23 95 A short backup (few megabytes) and restore procedure
63 * was successful ! (Using tar cvf ... on the block
64 * device interface).
65 * A longer backup resulted in major swapping, bad
66 * overall Linux performance and eventually failed as
67 * we received non serial read-ahead requests from the
68 * buffer cache.
69 * Ver 0.3 Nov 28 95 Long backups are now possible, thanks to the
70 * character device interface. Linux's responsiveness
71 * and performance doesn't seem to be much affected
72 * from the background backup procedure.
73 * Some general mtio.h magnetic tape operations are
74 * now supported by our character device. As a result,
75 * popular tape utilities are starting to work with
76 * ide tapes :-)
77 * The following configurations were tested:
78 * 1. An IDE ATAPI TAPE shares the same interface
79 * and irq with an IDE ATAPI CDROM.
80 * 2. An IDE ATAPI TAPE shares the same interface
81 * and irq with a normal IDE disk.
82 * Both configurations seemed to work just fine !
83 * However, to be on the safe side, it is meanwhile
84 * recommended to give the IDE TAPE its own interface
85 * and irq.
86 * The one thing which needs to be done here is to
87 * add a "request postpone" feature to ide.c,
88 * so that we won't have to wait for the tape to finish
89 * performing a long media access (DSC) request (such
90 * as a rewind) before we can access the other device
91 * on the same interface. This effect doesn't disturb
92 * normal operation most of the time because read/write
93 * requests are relatively fast, and once we are
94 * performing one tape r/w request, a lot of requests
95 * from the other device can be queued and ide.c will
96 * service all of them after this single tape request.
97 * Ver 1.0 Dec 11 95 Integrated into Linux 1.3.46 development tree.
98 * On each read / write request, we now ask the drive
99 * if we can transfer a constant number of bytes
100 * (a parameter of the drive) only to its buffers,
101 * without causing actual media access. If we can't,
102 * we just wait until we can by polling the DSC bit.
103 * This ensures that while we are not transferring
104 * more bytes than the constant referred to above, the
105 * interrupt latency will not become too high and
106 * we won't cause an interrupt timeout, as happened
107 * occasionally in the previous version.
108 * While polling for DSC, the current request is
109 * postponed and ide.c is free to handle requests from
110 * the other device. This is handled transparently to
111 * ide.c. The hwgroup locking method which was used
112 * in the previous version was removed.
113 * Use of new general features which are provided by
114 * ide.c for use with atapi devices.
115 * (Programming done by Mark Lord)
116 * Few potential bug fixes (Again, suggested by Mark)
117 * Single character device data transfers are now
118 * not limited in size, as they were before.
119 * We are asking the tape about its recommended
120 * transfer unit and send a larger data transfer
121 * as several transfers of the above size.
122 * For best results, use an integral number of this
123 * basic unit (which is shown during driver
124 * initialization). I will soon add an ioctl to get
125 * this important parameter.
126 * Our data transfer buffer is allocated on startup,
127 * rather than before each data transfer. This should
128 * ensure that we will indeed have a data buffer.
129 * Ver 1.1 Dec 14 95 Fixed random problems which occurred when the tape
130 * shared an interface with another device.
131 * (poll_for_dsc was a complete mess).
132 * Removed some old (non-active) code which had
133 * to do with supporting buffer cache originated
134 * requests.
135 * The block device interface can now be opened, so
136 * that general ide driver features like the unmask
137 * interrupts flag can be selected with an ioctl.
138 * This is the only use of the block device interface.
139 * New fast pipelined operation mode (currently only on
140 * writes). When using the pipelined mode, the
141 * throughput can potentially reach the maximum
142 * tape supported throughput, regardless of the
143 * user backup program. On my tape drive, it sometimes
144 * boosted performance by a factor of 2. Pipelined
145 * mode is enabled by default, but since it has a few
146 * downfalls as well, you may want to disable it.
147 * A short explanation of the pipelined operation mode
148 * is available below.
149 * Ver 1.2 Jan 1 96 Eliminated pipelined mode race condition.
150 * Added pipeline read mode. As a result, restores
151 * are now as fast as backups.
152 * Optimized shared interface behavior. The new behavior
153 * typically results in better IDE bus efficiency and
154 * higher tape throughput.
155 * Pre-calculation of the expected read/write request
156 * service time, based on the tape's parameters. In
157 * the pipelined operation mode, this allows us to
158 * adjust our polling frequency to a much lower value,
159 * and thus to dramatically reduce our load on Linux,
160 * without any decrease in performance.
161 * Implemented additional mtio.h operations.
162 * The recommended user block size is returned by
163 * the MTIOCGET ioctl.
164 * Additional minor changes.
165 * Ver 1.3 Feb 9 96 Fixed pipelined read mode bug which prevented the
166 * use of some block sizes during a restore procedure.
167 * The character device interface will now present a
168 * continuous view of the media - any mix of block sizes
169 * during a backup/restore procedure is supported. The
170 * driver will buffer the requests internally and
171 * convert them to the tape's recommended transfer
172 * unit, making performance almost independent of the
173 * chosen user block size.
174 * Some improvements in error recovery.
175 * By cooperating with ide-dma.c, bus mastering DMA can
176 * now sometimes be used with IDE tape drives as well.
177 * Bus mastering DMA has the potential to dramatically
178 * reduce the CPU's overhead when accessing the device,
179 * and can be enabled by using hdparm -d1 on the tape's
180 * block device interface. For more info, read the
181 * comments in ide-dma.c.
182 * Ver 1.4 Mar 13 96 Fixed serialize support.
183 * Ver 1.5 Apr 12 96 Fixed shared interface operation, broken in 1.3.85.
184 * Fixed pipelined read mode inefficiency.
185 * Fixed nasty null dereferencing bug.
186 * Ver 1.6 Aug 16 96 Fixed FPU usage in the driver.
187 * Fixed end of media bug.
188 * Ver 1.7 Sep 10 96 Minor changes for the CONNER CTT8000-A model.
189 * Ver 1.8 Sep 26 96 Attempt to find a better balance between good
190 * interactive response and high system throughput.
191 * Ver 1.9 Nov 5 96 Automatically cross encountered filemarks rather
192 * than requiring an explicit FSF command.
193 * Abort pending requests at end of media.
194 * MTTELL was sometimes returning incorrect results.
195 * Return the real block size in the MTIOCGET ioctl.
196 * Some error recovery bug fixes.
197 * Ver 1.10 Nov 5 96 Major reorganization.
198 * Reduced CPU overhead a bit by eliminating internal
199 * bounce buffers.
200 * Added module support.
201 * Added multiple tape drives support.
202 * Added partition support.
203 * Rewrote DSC handling.
204 * Some portability fixes.
205 * Removed ide-tape.h.
206 * Additional minor changes.
207 * Ver 1.11 Dec 2 96 Bug fix in previous DSC timeout handling.
208 * Use ide_stall_queue() for DSC overlap.
209 * Use the maximum speed rather than the current speed
210 * to compute the request service time.
211 * Ver 1.12 Dec 7 97 Fix random memory overwriting and/or last block data
212 * corruption, which could occur if the total number
213 * of bytes written to the tape was not an integral
214 * number of tape blocks.
215 * Add support for INTERRUPT DRQ devices.
216 * Ver 1.13 Jan 2 98 Add "speed == 0" work-around for HP COLORADO 5GB
217 * Ver 1.14 Dec 30 98 Partial fixes for the Sony/AIWA tape drives.
218 * Replace cli()/sti() with hwgroup spinlocks.
219 * Ver 1.15 Mar 25 99 Fix SMP race condition by replacing hwgroup
220 * spinlock with private per-tape spinlock.
221 * Ver 1.16 Sep 1 99 Add OnStream tape support.
222 * Abort read pipeline on EOD.
223 * Wait for the tape to become ready in case it returns
224 * "in the process of becoming ready" on open().
225 * Fix zero padding of the last written block in
226 * case the tape block size is larger than PAGE_SIZE.
227 * Decrease the default disconnection time to tn.
228 * Ver 1.16e Oct 3 99 Minor fixes.
229 * Ver 1.16e1 Oct 13 99 Patches by Arnold Niessen,
230 * niessen@iae.nl / arnold.niessen@philips.com
231 * GO-1) Undefined code in idetape_read_position
232 * according to Gadi's email
233 * AJN-1) Minor fix asc == 11 should be asc == 0x11
234 * in idetape_issue_packet_command (did effect
235 * debugging output only)
236 * AJN-2) Added more debugging output, and
237 * added ide-tape: where missing. I would also
238 * like to add tape->name where possible
239 * AJN-3) Added different debug_level's
240 * via /proc/ide/hdc/settings
241 * "debug_level" determines amount of debugging output;
242 * can be changed using /proc/ide/hdx/settings
243 * 0 : almost no debugging output
244 * 1 : 0+output errors only
245 * 2 : 1+output all sensekey/asc
246 * 3 : 2+follow all chrdev related procedures
247 * 4 : 3+follow all procedures
248 * 5 : 4+include pc_stack rq_stack info
249 * 6 : 5+USE_COUNT updates
250 * AJN-4) Fixed timeout for retension in idetape_queue_pc_tail
251 * from 5 to 10 minutes
252 * AJN-5) Changed maximum number of blocks to skip when
253 * reading tapes with multiple consecutive write
254 * errors from 100 to 1000 in idetape_get_logical_blk
255 * Proposed changes to code:
256 * 1) output "logical_blk_num" via /proc
257 * 2) output "current_operation" via /proc
258 * 3) Either solve or document the fact that `mt rewind' is
259 * required after reading from /dev/nhtx to be
260 * able to rmmod the idetape module;
261 * Also, sometimes an application finishes but the
262 * device remains `busy' for some time. Same cause ?
263 * Proposed changes to release-notes:
264 * 4) write a simple `quickstart' section in the
265 * release notes; I volunteer if you don't want to
266 * 5) include a pointer to video4linux in the doc
267 * to stimulate video applications
268 * 6) release notes lines 331 and 362: explain what happens
269 * if the application data rate is higher than 1100 KB/s;
270 * similar approach to lower-than-500 kB/s ?
271 * 7) 6.6 Comparison; wouldn't it be better to allow different
272 * strategies for read and write ?
273 * Wouldn't it be better to control the tape buffer
274 * contents instead of the bandwidth ?
275 * 8) line 536: replace will by would (if I understand
276 * this section correctly, a hypothetical and unwanted situation
277 * is being described)
278 * Ver 1.16f Dec 15 99 Change place of the secondary OnStream header frames.
279 * Ver 1.17 Nov 2000 / Jan 2001 Marcel Mol, marcel@mesa.nl
280 * - Add idetape_onstream_mode_sense_tape_parameter_page
281 * function to get tape capacity in frames: tape->capacity.
282 * - Add support for DI-50 drives( or any DI- drive).
283 * - 'workaround' for read error/blank block around block 3000.
284 * - Implement Early warning for end of media for Onstream.
285 * - Cosmetic code changes for readability.
286 * - Idetape_position_tape should not use SKIP bit during
287 * Onstream read recovery.
288 * - Add capacity, logical_blk_num and first/last_frame_position
289 * to /proc/ide/hd?/settings.
290 * - Module use count was gone in the Linux 2.4 driver.
291 * Ver 1.17a Apr 2001 Willem Riede osst@riede.org
292 * - Get drive's actual block size from mode sense block descriptor
293 * - Limit size of pipeline
294 * Ver 1.17b Oct 2002 Alan Stern <stern@rowland.harvard.edu>
295 * Changed IDETAPE_MIN_PIPELINE_STAGES to 1 and actually used
296 * it in the code!
297 * Actually removed aborted stages in idetape_abort_pipeline
298 * instead of just changing the command code.
299 * Made the transfer byte count for Request Sense equal to the
300 * actual length of the data transfer.
301 * Changed handling of partial data transfers: they do not
302 * cause DMA errors.
303 * Moved initiation of DMA transfers to the correct place.
304 * Removed reference to unallocated memory.
305 * Made __idetape_discard_read_pipeline return the number of
306 * sectors skipped, not the number of stages.
307 * Replaced errant kfree() calls with __idetape_kfree_stage().
308 * Fixed off-by-one error in testing the pipeline length.
309 * Fixed handling of filemarks in the read pipeline.
310 * Small code optimization for MTBSF and MTBSFM ioctls.
311 * Don't try to unlock the door during device close if is
312 * already unlocked!
313 * Cosmetic fixes to miscellaneous debugging output messages.
314 * Set the minimum /proc/ide/hd?/settings values for "pipeline",
315 * "pipeline_min", and "pipeline_max" to 1.
316 *
317 * Here are some words from the first releases of hd.c, which are quoted
318 * in ide.c and apply here as well:
319 *
320 * | Special care is recommended. Have Fun!
321 *
322 */
324 /*
325 * An overview of the pipelined operation mode.
326 *
327 * In the pipelined write mode, we will usually just add requests to our
328 * pipeline and return immediately, before we even start to service them. The
329 * user program will then have enough time to prepare the next request while
330 * we are still busy servicing previous requests. In the pipelined read mode,
331 * the situation is similar - we add read-ahead requests into the pipeline,
332 * before the user even requested them.
333 *
334 * The pipeline can be viewed as a "safety net" which will be activated when
335 * the system load is high and prevents the user backup program from keeping up
336 * with the current tape speed. At this point, the pipeline will get
337 * shorter and shorter but the tape will still be streaming at the same speed.
338 * Assuming we have enough pipeline stages, the system load will hopefully
339 * decrease before the pipeline is completely empty, and the backup program
340 * will be able to "catch up" and refill the pipeline again.
341 *
342 * When using the pipelined mode, it would be best to disable any type of
343 * buffering done by the user program, as ide-tape already provides all the
344 * benefits in the kernel, where it can be done in a more efficient way.
345 * As we will usually not block the user program on a request, the most
346 * efficient user code will then be a simple read-write-read-... cycle.
347 * Any additional logic will usually just slow down the backup process.
348 *
349 * Using the pipelined mode, I get a constant over 400 KBps throughput,
350 * which seems to be the maximum throughput supported by my tape.
351 *
352 * However, there are some downfalls:
353 *
354 * 1. We use memory (for data buffers) in proportional to the number
355 * of pipeline stages (each stage is about 26 KB with my tape).
356 * 2. In the pipelined write mode, we cheat and postpone error codes
357 * to the user task. In read mode, the actual tape position
358 * will be a bit further than the last requested block.
359 *
360 * Concerning (1):
361 *
362 * 1. We allocate stages dynamically only when we need them. When
363 * we don't need them, we don't consume additional memory. In
364 * case we can't allocate stages, we just manage without them
365 * (at the expense of decreased throughput) so when Linux is
366 * tight in memory, we will not pose additional difficulties.
367 *
368 * 2. The maximum number of stages (which is, in fact, the maximum
369 * amount of memory) which we allocate is limited by the compile
370 * time parameter IDETAPE_MAX_PIPELINE_STAGES.
371 *
372 * 3. The maximum number of stages is a controlled parameter - We
373 * don't start from the user defined maximum number of stages
374 * but from the lower IDETAPE_MIN_PIPELINE_STAGES (again, we
375 * will not even allocate this amount of stages if the user
376 * program can't handle the speed). We then implement a feedback
377 * loop which checks if the pipeline is empty, and if it is, we
378 * increase the maximum number of stages as necessary until we
379 * reach the optimum value which just manages to keep the tape
380 * busy with minimum allocated memory or until we reach
381 * IDETAPE_MAX_PIPELINE_STAGES.
382 *
383 * Concerning (2):
384 *
385 * In pipelined write mode, ide-tape can not return accurate error codes
386 * to the user program since we usually just add the request to the
387 * pipeline without waiting for it to be serviced. In case an error
388 * occurs, I will report it on the next user request.
389 *
390 * In the pipelined read mode, subsequent read requests or forward
391 * filemark spacing will perform correctly, as we preserve all blocks
392 * and filemarks which we encountered during our excess read-ahead.
393 *
394 * For accurate tape positioning and error reporting, disabling
395 * pipelined mode might be the best option.
396 *
397 * You can enable/disable/tune the pipelined operation mode by adjusting
398 * the compile time parameters below.
399 */
401 /*
402 * Possible improvements.
403 *
404 * 1. Support for the ATAPI overlap protocol.
405 *
406 * In order to maximize bus throughput, we currently use the DSC
407 * overlap method which enables ide.c to service requests from the
408 * other device while the tape is busy executing a command. The
409 * DSC overlap method involves polling the tape's status register
410 * for the DSC bit, and servicing the other device while the tape
411 * isn't ready.
412 *
413 * In the current QIC development standard (December 1995),
414 * it is recommended that new tape drives will *in addition*
415 * implement the ATAPI overlap protocol, which is used for the
416 * same purpose - efficient use of the IDE bus, but is interrupt
417 * driven and thus has much less CPU overhead.
418 *
419 * ATAPI overlap is likely to be supported in most new ATAPI
420 * devices, including new ATAPI cdroms, and thus provides us
421 * a method by which we can achieve higher throughput when
422 * sharing a (fast) ATA-2 disk with any (slow) new ATAPI device.
423 */
425 #define IDETAPE_VERSION "1.19"
427 #include <linux/module.h>
428 #include <linux/types.h>
429 #include <linux/string.h>
430 #include <linux/kernel.h>
431 #include <linux/delay.h>
432 #include <linux/timer.h>
433 #include <linux/mm.h>
434 #include <linux/interrupt.h>
435 #include <linux/jiffies.h>
436 #include <linux/major.h>
437 #include <linux/errno.h>
438 #include <linux/genhd.h>
439 #include <linux/slab.h>
440 #include <linux/pci.h>
441 #include <linux/ide.h>
442 #include <linux/smp_lock.h>
443 #include <linux/completion.h>
444 #include <linux/bitops.h>
445 #include <linux/mutex.h>
447 #include <asm/byteorder.h>
448 #include <asm/irq.h>
449 #include <asm/uaccess.h>
450 #include <asm/io.h>
451 #include <asm/unaligned.h>
453 /*
454 * partition
455 */
456 typedef struct os_partition_s {
457 __u8 partition_num;
458 __u8 par_desc_ver;
459 __u16 wrt_pass_cntr;
460 __u32 first_frame_addr;
461 __u32 last_frame_addr;
462 __u32 eod_frame_addr;
463 } os_partition_t;
465 /*
466 * DAT entry
467 */
468 typedef struct os_dat_entry_s {
469 __u32 blk_sz;
470 __u16 blk_cnt;
471 __u8 flags;
472 __u8 reserved;
473 } os_dat_entry_t;
475 /*
476 * DAT
477 */
478 #define OS_DAT_FLAGS_DATA (0xc)
479 #define OS_DAT_FLAGS_MARK (0x1)
481 typedef struct os_dat_s {
482 __u8 dat_sz;
483 __u8 reserved1;
484 __u8 entry_cnt;
485 __u8 reserved3;
486 os_dat_entry_t dat_list[16];
487 } os_dat_t;
489 #include <linux/mtio.h>
491 /**************************** Tunable parameters *****************************/
494 /*
495 * Pipelined mode parameters.
496 *
497 * We try to use the minimum number of stages which is enough to
498 * keep the tape constantly streaming. To accomplish that, we implement
499 * a feedback loop around the maximum number of stages:
500 *
501 * We start from MIN maximum stages (we will not even use MIN stages
502 * if we don't need them), increment it by RATE*(MAX-MIN)
503 * whenever we sense that the pipeline is empty, until we reach
504 * the optimum value or until we reach MAX.
505 *
506 * Setting the following parameter to 0 is illegal: the pipelined mode
507 * cannot be disabled (calculate_speeds() divides by tape->max_stages.)
508 */
509 #define IDETAPE_MIN_PIPELINE_STAGES 1
510 #define IDETAPE_MAX_PIPELINE_STAGES 400
511 #define IDETAPE_INCREASE_STAGES_RATE 20
513 /*
514 * The following are used to debug the driver:
515 *
516 * Setting IDETAPE_DEBUG_INFO to 1 will report device capabilities.
517 * Setting IDETAPE_DEBUG_LOG to 1 will log driver flow control.
518 * Setting IDETAPE_DEBUG_BUGS to 1 will enable self-sanity checks in
519 * some places.
520 *
521 * Setting them to 0 will restore normal operation mode:
522 *
523 * 1. Disable logging normal successful operations.
524 * 2. Disable self-sanity checks.
525 * 3. Errors will still be logged, of course.
526 *
527 * All the #if DEBUG code will be removed some day, when the driver
528 * is verified to be stable enough. This will make it much more
529 * esthetic.
530 */
531 #define IDETAPE_DEBUG_INFO 0
532 #define IDETAPE_DEBUG_LOG 0
533 #define IDETAPE_DEBUG_BUGS 1
535 /*
536 * After each failed packet command we issue a request sense command
537 * and retry the packet command IDETAPE_MAX_PC_RETRIES times.
538 *
539 * Setting IDETAPE_MAX_PC_RETRIES to 0 will disable retries.
540 */
541 #define IDETAPE_MAX_PC_RETRIES 3
543 /*
544 * With each packet command, we allocate a buffer of
545 * IDETAPE_PC_BUFFER_SIZE bytes. This is used for several packet
546 * commands (Not for READ/WRITE commands).
547 */
548 #define IDETAPE_PC_BUFFER_SIZE 256
550 /*
551 * In various places in the driver, we need to allocate storage
552 * for packet commands and requests, which will remain valid while
553 * we leave the driver to wait for an interrupt or a timeout event.
554 */
555 #define IDETAPE_PC_STACK (10 + IDETAPE_MAX_PC_RETRIES)
557 /*
558 * Some drives (for example, Seagate STT3401A Travan) require a very long
559 * timeout, because they don't return an interrupt or clear their busy bit
560 * until after the command completes (even retension commands).
561 */
562 #define IDETAPE_WAIT_CMD (900*HZ)
564 /*
565 * The following parameter is used to select the point in the internal
566 * tape fifo in which we will start to refill the buffer. Decreasing
567 * the following parameter will improve the system's latency and
568 * interactive response, while using a high value might improve sytem
569 * throughput.
570 */
571 #define IDETAPE_FIFO_THRESHOLD 2
573 /*
574 * DSC polling parameters.
575 *
576 * Polling for DSC (a single bit in the status register) is a very
577 * important function in ide-tape. There are two cases in which we
578 * poll for DSC:
579 *
580 * 1. Before a read/write packet command, to ensure that we
581 * can transfer data from/to the tape's data buffers, without
582 * causing an actual media access. In case the tape is not
583 * ready yet, we take out our request from the device
584 * request queue, so that ide.c will service requests from
585 * the other device on the same interface meanwhile.
586 *
587 * 2. After the successful initialization of a "media access
588 * packet command", which is a command which can take a long
589 * time to complete (it can be several seconds or even an hour).
590 *
591 * Again, we postpone our request in the middle to free the bus
592 * for the other device. The polling frequency here should be
593 * lower than the read/write frequency since those media access
594 * commands are slow. We start from a "fast" frequency -
595 * IDETAPE_DSC_MA_FAST (one second), and if we don't receive DSC
596 * after IDETAPE_DSC_MA_THRESHOLD (5 minutes), we switch it to a
597 * lower frequency - IDETAPE_DSC_MA_SLOW (1 minute).
598 *
599 * We also set a timeout for the timer, in case something goes wrong.
600 * The timeout should be longer then the maximum execution time of a
601 * tape operation.
602 */
604 /*
605 * DSC timings.
606 */
607 #define IDETAPE_DSC_RW_MIN 5*HZ/100 /* 50 msec */
608 #define IDETAPE_DSC_RW_MAX 40*HZ/100 /* 400 msec */
609 #define IDETAPE_DSC_RW_TIMEOUT 2*60*HZ /* 2 minutes */
610 #define IDETAPE_DSC_MA_FAST 2*HZ /* 2 seconds */
611 #define IDETAPE_DSC_MA_THRESHOLD 5*60*HZ /* 5 minutes */
612 #define IDETAPE_DSC_MA_SLOW 30*HZ /* 30 seconds */
613 #define IDETAPE_DSC_MA_TIMEOUT 2*60*60*HZ /* 2 hours */
615 /*************************** End of tunable parameters ***********************/
617 /*
618 * Debugging/Performance analysis
619 *
620 * I/O trace support
621 */
622 #define USE_IOTRACE 0
623 #if USE_IOTRACE
624 #include <linux/io_trace.h>
625 #define IO_IDETAPE_FIFO 500
626 #endif
628 /*
629 * Read/Write error simulation
630 */
631 #define SIMULATE_ERRORS 0
633 /*
634 * For general magnetic tape device compatibility.
635 */
636 typedef enum {
637 idetape_direction_none,
638 idetape_direction_read,
639 idetape_direction_write
640 } idetape_chrdev_direction_t;
642 struct idetape_bh {
643 unsigned short b_size;
644 atomic_t b_count;
645 struct idetape_bh *b_reqnext;
646 char *b_data;
647 };
649 /*
650 * Our view of a packet command.
651 */
652 typedef struct idetape_packet_command_s {
653 u8 c[12]; /* Actual packet bytes */
654 int retries; /* On each retry, we increment retries */
655 int error; /* Error code */
656 int request_transfer; /* Bytes to transfer */
657 int actually_transferred; /* Bytes actually transferred */
658 int buffer_size; /* Size of our data buffer */
659 struct idetape_bh *bh;
660 char *b_data;
661 int b_count;
662 u8 *buffer; /* Data buffer */
663 u8 *current_position; /* Pointer into the above buffer */
664 ide_startstop_t (*callback) (ide_drive_t *); /* Called when this packet command is completed */
665 u8 pc_buffer[IDETAPE_PC_BUFFER_SIZE]; /* Temporary buffer */
666 unsigned long flags; /* Status/Action bit flags: long for set_bit */
667 } idetape_pc_t;
669 /*
670 * Packet command flag bits.
671 */
672 /* Set when an error is considered normal - We won't retry */
673 #define PC_ABORT 0
674 /* 1 When polling for DSC on a media access command */
675 #define PC_WAIT_FOR_DSC 1
676 /* 1 when we prefer to use DMA if possible */
677 #define PC_DMA_RECOMMENDED 2
678 /* 1 while DMA in progress */
679 #define PC_DMA_IN_PROGRESS 3
680 /* 1 when encountered problem during DMA */
681 #define PC_DMA_ERROR 4
682 /* Data direction */
683 #define PC_WRITING 5
685 /*
686 * Capabilities and Mechanical Status Page
687 */
688 typedef struct {
689 unsigned page_code :6; /* Page code - Should be 0x2a */
690 __u8 reserved0_6 :1;
691 __u8 ps :1; /* parameters saveable */
692 __u8 page_length; /* Page Length - Should be 0x12 */
693 __u8 reserved2, reserved3;
694 unsigned ro :1; /* Read Only Mode */
695 unsigned reserved4_1234 :4;
696 unsigned sprev :1; /* Supports SPACE in the reverse direction */
697 unsigned reserved4_67 :2;
698 unsigned reserved5_012 :3;
699 unsigned efmt :1; /* Supports ERASE command initiated formatting */
700 unsigned reserved5_4 :1;
701 unsigned qfa :1; /* Supports the QFA two partition formats */
702 unsigned reserved5_67 :2;
703 unsigned lock :1; /* Supports locking the volume */
704 unsigned locked :1; /* The volume is locked */
705 unsigned prevent :1; /* The device defaults in the prevent state after power up */
706 unsigned eject :1; /* The device can eject the volume */
707 __u8 disconnect :1; /* The device can break request > ctl */
708 __u8 reserved6_5 :1;
709 unsigned ecc :1; /* Supports error correction */
710 unsigned cmprs :1; /* Supports data compression */
711 unsigned reserved7_0 :1;
712 unsigned blk512 :1; /* Supports 512 bytes block size */
713 unsigned blk1024 :1; /* Supports 1024 bytes block size */
714 unsigned reserved7_3_6 :4;
715 unsigned blk32768 :1; /* slowb - the device restricts the byte count for PIO */
716 /* transfers for slow buffer memory ??? */
717 /* Also 32768 block size in some cases */
718 __u16 max_speed; /* Maximum speed supported in KBps */
719 __u8 reserved10, reserved11;
720 __u16 ctl; /* Continuous Transfer Limit in blocks */
721 __u16 speed; /* Current Speed, in KBps */
722 __u16 buffer_size; /* Buffer Size, in 512 bytes */
723 __u8 reserved18, reserved19;
724 } idetape_capabilities_page_t;
726 /*
727 * Block Size Page
728 */
729 typedef struct {
730 unsigned page_code :6; /* Page code - Should be 0x30 */
731 unsigned reserved1_6 :1;
732 unsigned ps :1;
733 __u8 page_length; /* Page Length - Should be 2 */
734 __u8 reserved2;
735 unsigned play32 :1;
736 unsigned play32_5 :1;
737 unsigned reserved2_23 :2;
738 unsigned record32 :1;
739 unsigned record32_5 :1;
740 unsigned reserved2_6 :1;
741 unsigned one :1;
742 } idetape_block_size_page_t;
744 /*
745 * A pipeline stage.
746 */
747 typedef struct idetape_stage_s {
748 struct request rq; /* The corresponding request */
749 struct idetape_bh *bh; /* The data buffers */
750 struct idetape_stage_s *next; /* Pointer to the next stage */
751 } idetape_stage_t;
753 /*
754 * REQUEST SENSE packet command result - Data Format.
755 */
756 typedef struct {
757 unsigned error_code :7; /* Current of deferred errors */
758 unsigned valid :1; /* The information field conforms to QIC-157C */
759 __u8 reserved1 :8; /* Segment Number - Reserved */
760 unsigned sense_key :4; /* Sense Key */
761 unsigned reserved2_4 :1; /* Reserved */
762 unsigned ili :1; /* Incorrect Length Indicator */
763 unsigned eom :1; /* End Of Medium */
764 unsigned filemark :1; /* Filemark */
765 __u32 information __attribute__ ((packed));
766 __u8 asl; /* Additional sense length (n-7) */
767 __u32 command_specific; /* Additional command specific information */
768 __u8 asc; /* Additional Sense Code */
769 __u8 ascq; /* Additional Sense Code Qualifier */
770 __u8 replaceable_unit_code; /* Field Replaceable Unit Code */
771 unsigned sk_specific1 :7; /* Sense Key Specific */
772 unsigned sksv :1; /* Sense Key Specific information is valid */
773 __u8 sk_specific2; /* Sense Key Specific */
774 __u8 sk_specific3; /* Sense Key Specific */
775 __u8 pad[2]; /* Padding to 20 bytes */
776 } idetape_request_sense_result_t;
779 /*
780 * Most of our global data which we need to save even as we leave the
781 * driver due to an interrupt or a timer event is stored in a variable
782 * of type idetape_tape_t, defined below.
783 */
784 typedef struct ide_tape_obj {
785 ide_drive_t *drive;
786 ide_driver_t *driver;
787 struct gendisk *disk;
788 struct kref kref;
790 /*
791 * Since a typical character device operation requires more
792 * than one packet command, we provide here enough memory
793 * for the maximum of interconnected packet commands.
794 * The packet commands are stored in the circular array pc_stack.
795 * pc_stack_index points to the last used entry, and warps around
796 * to the start when we get to the last array entry.
797 *
798 * pc points to the current processed packet command.
799 *
800 * failed_pc points to the last failed packet command, or contains
801 * NULL if we do not need to retry any packet command. This is
802 * required since an additional packet command is needed before the
803 * retry, to get detailed information on what went wrong.
804 */
805 /* Current packet command */
806 idetape_pc_t *pc;
807 /* Last failed packet command */
808 idetape_pc_t *failed_pc;
809 /* Packet command stack */
810 idetape_pc_t pc_stack[IDETAPE_PC_STACK];
811 /* Next free packet command storage space */
812 int pc_stack_index;
813 struct request rq_stack[IDETAPE_PC_STACK];
814 /* We implement a circular array */
815 int rq_stack_index;
817 /*
818 * DSC polling variables.
819 *
820 * While polling for DSC we use postponed_rq to postpone the
821 * current request so that ide.c will be able to service
822 * pending requests on the other device. Note that at most
823 * we will have only one DSC (usually data transfer) request
824 * in the device request queue. Additional requests can be
825 * queued in our internal pipeline, but they will be visible
826 * to ide.c only one at a time.
827 */
828 struct request *postponed_rq;
829 /* The time in which we started polling for DSC */
830 unsigned long dsc_polling_start;
831 /* Timer used to poll for dsc */
832 struct timer_list dsc_timer;
833 /* Read/Write dsc polling frequency */
834 unsigned long best_dsc_rw_frequency;
835 /* The current polling frequency */
836 unsigned long dsc_polling_frequency;
837 /* Maximum waiting time */
838 unsigned long dsc_timeout;
840 /*
841 * Read position information
842 */
843 u8 partition;
844 /* Current block */
845 unsigned int first_frame_position;
846 unsigned int last_frame_position;
847 unsigned int blocks_in_buffer;
849 /*
850 * Last error information
851 */
852 u8 sense_key, asc, ascq;
854 /*
855 * Character device operation
856 */
857 unsigned int minor;
858 /* device name */
859 char name[4];
860 /* Current character device data transfer direction */
861 idetape_chrdev_direction_t chrdev_direction;
863 /*
864 * Device information
865 */
866 /* Usually 512 or 1024 bytes */
867 unsigned short tape_block_size;
868 int user_bs_factor;
869 /* Copy of the tape's Capabilities and Mechanical Page */
870 idetape_capabilities_page_t capabilities;
872 /*
873 * Active data transfer request parameters.
874 *
875 * At most, there is only one ide-tape originated data transfer
876 * request in the device request queue. This allows ide.c to
877 * easily service requests from the other device when we
878 * postpone our active request. In the pipelined operation
879 * mode, we use our internal pipeline structure to hold
880 * more data requests.
881 *
882 * The data buffer size is chosen based on the tape's
883 * recommendation.
884 */
885 /* Pointer to the request which is waiting in the device request queue */
886 struct request *active_data_request;
887 /* Data buffer size (chosen based on the tape's recommendation */
888 int stage_size;
889 idetape_stage_t *merge_stage;
890 int merge_stage_size;
891 struct idetape_bh *bh;
892 char *b_data;
893 int b_count;
895 /*
896 * Pipeline parameters.
897 *
898 * To accomplish non-pipelined mode, we simply set the following
899 * variables to zero (or NULL, where appropriate).
900 */
901 /* Number of currently used stages */
902 int nr_stages;
903 /* Number of pending stages */
904 int nr_pending_stages;
905 /* We will not allocate more than this number of stages */
906 int max_stages, min_pipeline, max_pipeline;
907 /* The first stage which will be removed from the pipeline */
908 idetape_stage_t *first_stage;
909 /* The currently active stage */
910 idetape_stage_t *active_stage;
911 /* Will be serviced after the currently active request */
912 idetape_stage_t *next_stage;
913 /* New requests will be added to the pipeline here */
914 idetape_stage_t *last_stage;
915 /* Optional free stage which we can use */
916 idetape_stage_t *cache_stage;
917 int pages_per_stage;
918 /* Wasted space in each stage */
919 int excess_bh_size;
921 /* Status/Action flags: long for set_bit */
922 unsigned long flags;
923 /* protects the ide-tape queue */
924 spinlock_t spinlock;
926 /*
927 * Measures average tape speed
928 */
929 unsigned long avg_time;
930 int avg_size;
931 int avg_speed;
933 /* last sense information */
934 idetape_request_sense_result_t sense;
936 char vendor_id[10];
937 char product_id[18];
938 char firmware_revision[6];
939 int firmware_revision_num;
941 /* the door is currently locked */
942 int door_locked;
943 /* the tape hardware is write protected */
944 char drv_write_prot;
945 /* the tape is write protected (hardware or opened as read-only) */
946 char write_prot;
948 /*
949 * Limit the number of times a request can
950 * be postponed, to avoid an infinite postpone
951 * deadlock.
952 */
953 /* request postpone count limit */
954 int postpone_cnt;
956 /*
957 * Measures number of frames:
958 *
959 * 1. written/read to/from the driver pipeline (pipeline_head).
960 * 2. written/read to/from the tape buffers (idetape_bh).
961 * 3. written/read by the tape to/from the media (tape_head).
962 */
963 int pipeline_head;
964 int buffer_head;
965 int tape_head;
966 int last_tape_head;
968 /*
969 * Speed control at the tape buffers input/output
970 */
971 unsigned long insert_time;
972 int insert_size;
973 int insert_speed;
974 int max_insert_speed;
975 int measure_insert_time;
977 /*
978 * Measure tape still time, in milliseconds
979 */
980 unsigned long tape_still_time_begin;
981 int tape_still_time;
983 /*
984 * Speed regulation negative feedback loop
985 */
986 int speed_control;
987 int pipeline_head_speed;
988 int controlled_pipeline_head_speed;
989 int uncontrolled_pipeline_head_speed;
990 int controlled_last_pipeline_head;
991 int uncontrolled_last_pipeline_head;
992 unsigned long uncontrolled_pipeline_head_time;
993 unsigned long controlled_pipeline_head_time;
994 int controlled_previous_pipeline_head;
995 int uncontrolled_previous_pipeline_head;
996 unsigned long controlled_previous_head_time;
997 unsigned long uncontrolled_previous_head_time;
998 int restart_speed_control_req;
1000 /*
1001 * Debug_level determines amount of debugging output;
1002 * can be changed using /proc/ide/hdx/settings
1003 * 0 : almost no debugging output
1004 * 1 : 0+output errors only
1005 * 2 : 1+output all sensekey/asc
1006 * 3 : 2+follow all chrdev related procedures
1007 * 4 : 3+follow all procedures
1008 * 5 : 4+include pc_stack rq_stack info
1009 * 6 : 5+USE_COUNT updates
1010 */
1011 int debug_level;
1012 } idetape_tape_t;
1014 static DEFINE_MUTEX(idetape_ref_mutex);
1016 static struct class *idetape_sysfs_class;
1018 #define to_ide_tape(obj) container_of(obj, struct ide_tape_obj, kref)
1020 #define ide_tape_g(disk) \
1021 container_of((disk)->private_data, struct ide_tape_obj, driver)
1023 static struct ide_tape_obj *ide_tape_get(struct gendisk *disk)
1025 struct ide_tape_obj *tape = NULL;
1027 mutex_lock(&idetape_ref_mutex);
1028 tape = ide_tape_g(disk);
1029 if (tape)
1030 kref_get(&tape->kref);
1031 mutex_unlock(&idetape_ref_mutex);
1032 return tape;
1035 static void ide_tape_release(struct kref *);
1037 static void ide_tape_put(struct ide_tape_obj *tape)
1039 mutex_lock(&idetape_ref_mutex);
1040 kref_put(&tape->kref, ide_tape_release);
1041 mutex_unlock(&idetape_ref_mutex);
1044 /*
1045 * Tape door status
1046 */
1047 #define DOOR_UNLOCKED 0
1048 #define DOOR_LOCKED 1
1049 #define DOOR_EXPLICITLY_LOCKED 2
1051 /*
1052 * Tape flag bits values.
1053 */
1054 #define IDETAPE_IGNORE_DSC 0
1055 #define IDETAPE_ADDRESS_VALID 1 /* 0 When the tape position is unknown */
1056 #define IDETAPE_BUSY 2 /* Device already opened */
1057 #define IDETAPE_PIPELINE_ERROR 3 /* Error detected in a pipeline stage */
1058 #define IDETAPE_DETECT_BS 4 /* Attempt to auto-detect the current user block size */
1059 #define IDETAPE_FILEMARK 5 /* Currently on a filemark */
1060 #define IDETAPE_DRQ_INTERRUPT 6 /* DRQ interrupt device */
1061 #define IDETAPE_READ_ERROR 7
1062 #define IDETAPE_PIPELINE_ACTIVE 8 /* pipeline active */
1063 /* 0 = no tape is loaded, so we don't rewind after ejecting */
1064 #define IDETAPE_MEDIUM_PRESENT 9
1066 /*
1067 * Supported ATAPI tape drives packet commands
1068 */
1069 #define IDETAPE_TEST_UNIT_READY_CMD 0x00
1070 #define IDETAPE_REWIND_CMD 0x01
1071 #define IDETAPE_REQUEST_SENSE_CMD 0x03
1072 #define IDETAPE_READ_CMD 0x08
1073 #define IDETAPE_WRITE_CMD 0x0a
1074 #define IDETAPE_WRITE_FILEMARK_CMD 0x10
1075 #define IDETAPE_SPACE_CMD 0x11
1076 #define IDETAPE_INQUIRY_CMD 0x12
1077 #define IDETAPE_ERASE_CMD 0x19
1078 #define IDETAPE_MODE_SENSE_CMD 0x1a
1079 #define IDETAPE_MODE_SELECT_CMD 0x15
1080 #define IDETAPE_LOAD_UNLOAD_CMD 0x1b
1081 #define IDETAPE_PREVENT_CMD 0x1e
1082 #define IDETAPE_LOCATE_CMD 0x2b
1083 #define IDETAPE_READ_POSITION_CMD 0x34
1084 #define IDETAPE_READ_BUFFER_CMD 0x3c
1085 #define IDETAPE_SET_SPEED_CMD 0xbb
1087 /*
1088 * Some defines for the READ BUFFER command
1089 */
1090 #define IDETAPE_RETRIEVE_FAULTY_BLOCK 6
1092 /*
1093 * Some defines for the SPACE command
1094 */
1095 #define IDETAPE_SPACE_OVER_FILEMARK 1
1096 #define IDETAPE_SPACE_TO_EOD 3
1098 /*
1099 * Some defines for the LOAD UNLOAD command
1100 */
1101 #define IDETAPE_LU_LOAD_MASK 1
1102 #define IDETAPE_LU_RETENSION_MASK 2
1103 #define IDETAPE_LU_EOT_MASK 4
1105 /*
1106 * Special requests for our block device strategy routine.
1108 * In order to service a character device command, we add special
1109 * requests to the tail of our block device request queue and wait
1110 * for their completion.
1111 */
1113 enum {
1114 REQ_IDETAPE_PC1 = (1 << 0), /* packet command (first stage) */
1115 REQ_IDETAPE_PC2 = (1 << 1), /* packet command (second stage) */
1116 REQ_IDETAPE_READ = (1 << 2),
1117 REQ_IDETAPE_WRITE = (1 << 3),
1118 REQ_IDETAPE_READ_BUFFER = (1 << 4),
1119 };
1121 /*
1122 * Error codes which are returned in rq->errors to the higher part
1123 * of the driver.
1124 */
1125 #define IDETAPE_ERROR_GENERAL 101
1126 #define IDETAPE_ERROR_FILEMARK 102
1127 #define IDETAPE_ERROR_EOD 103
1129 /*
1130 * The following is used to format the general configuration word of
1131 * the ATAPI IDENTIFY DEVICE command.
1132 */
1133 struct idetape_id_gcw {
1134 unsigned packet_size :2; /* Packet Size */
1135 unsigned reserved234 :3; /* Reserved */
1136 unsigned drq_type :2; /* Command packet DRQ type */
1137 unsigned removable :1; /* Removable media */
1138 unsigned device_type :5; /* Device type */
1139 unsigned reserved13 :1; /* Reserved */
1140 unsigned protocol :2; /* Protocol type */
1141 };
1143 /*
1144 * INQUIRY packet command - Data Format (From Table 6-8 of QIC-157C)
1145 */
1146 typedef struct {
1147 unsigned device_type :5; /* Peripheral Device Type */
1148 unsigned reserved0_765 :3; /* Peripheral Qualifier - Reserved */
1149 unsigned reserved1_6t0 :7; /* Reserved */
1150 unsigned rmb :1; /* Removable Medium Bit */
1151 unsigned ansi_version :3; /* ANSI Version */
1152 unsigned ecma_version :3; /* ECMA Version */
1153 unsigned iso_version :2; /* ISO Version */
1154 unsigned response_format :4; /* Response Data Format */
1155 unsigned reserved3_45 :2; /* Reserved */
1156 unsigned reserved3_6 :1; /* TrmIOP - Reserved */
1157 unsigned reserved3_7 :1; /* AENC - Reserved */
1158 __u8 additional_length; /* Additional Length (total_length-4) */
1159 __u8 rsv5, rsv6, rsv7; /* Reserved */
1160 __u8 vendor_id[8]; /* Vendor Identification */
1161 __u8 product_id[16]; /* Product Identification */
1162 __u8 revision_level[4]; /* Revision Level */
1163 __u8 vendor_specific[20]; /* Vendor Specific - Optional */
1164 __u8 reserved56t95[40]; /* Reserved - Optional */
1165 /* Additional information may be returned */
1166 } idetape_inquiry_result_t;
1168 /*
1169 * READ POSITION packet command - Data Format (From Table 6-57)
1170 */
1171 typedef struct {
1172 unsigned reserved0_10 :2; /* Reserved */
1173 unsigned bpu :1; /* Block Position Unknown */
1174 unsigned reserved0_543 :3; /* Reserved */
1175 unsigned eop :1; /* End Of Partition */
1176 unsigned bop :1; /* Beginning Of Partition */
1177 u8 partition; /* Partition Number */
1178 u8 reserved2, reserved3; /* Reserved */
1179 u32 first_block; /* First Block Location */
1180 u32 last_block; /* Last Block Location (Optional) */
1181 u8 reserved12; /* Reserved */
1182 u8 blocks_in_buffer[3]; /* Blocks In Buffer - (Optional) */
1183 u32 bytes_in_buffer; /* Bytes In Buffer (Optional) */
1184 } idetape_read_position_result_t;
1186 /*
1187 * Follows structures which are related to the SELECT SENSE / MODE SENSE
1188 * packet commands. Those packet commands are still not supported
1189 * by ide-tape.
1190 */
1191 #define IDETAPE_BLOCK_DESCRIPTOR 0
1192 #define IDETAPE_CAPABILITIES_PAGE 0x2a
1193 #define IDETAPE_PARAMTR_PAGE 0x2b /* Onstream DI-x0 only */
1194 #define IDETAPE_BLOCK_SIZE_PAGE 0x30
1195 #define IDETAPE_BUFFER_FILLING_PAGE 0x33
1197 /*
1198 * Mode Parameter Header for the MODE SENSE packet command
1199 */
1200 typedef struct {
1201 __u8 mode_data_length; /* Length of the following data transfer */
1202 __u8 medium_type; /* Medium Type */
1203 __u8 dsp; /* Device Specific Parameter */
1204 __u8 bdl; /* Block Descriptor Length */
1205 #if 0
1206 /* data transfer page */
1207 __u8 page_code :6;
1208 __u8 reserved0_6 :1;
1209 __u8 ps :1; /* parameters saveable */
1210 __u8 page_length; /* page Length == 0x02 */
1211 __u8 reserved2;
1212 __u8 read32k :1; /* 32k blk size (data only) */
1213 __u8 read32k5 :1; /* 32.5k blk size (data&AUX) */
1214 __u8 reserved3_23 :2;
1215 __u8 write32k :1; /* 32k blk size (data only) */
1216 __u8 write32k5 :1; /* 32.5k blk size (data&AUX) */
1217 __u8 reserved3_6 :1;
1218 __u8 streaming :1; /* streaming mode enable */
1219 #endif
1220 } idetape_mode_parameter_header_t;
1222 /*
1223 * Mode Parameter Block Descriptor the MODE SENSE packet command
1225 * Support for block descriptors is optional.
1226 */
1227 typedef struct {
1228 __u8 density_code; /* Medium density code */
1229 __u8 blocks[3]; /* Number of blocks */
1230 __u8 reserved4; /* Reserved */
1231 __u8 length[3]; /* Block Length */
1232 } idetape_parameter_block_descriptor_t;
1234 /*
1235 * The Data Compression Page, as returned by the MODE SENSE packet command.
1236 */
1237 typedef struct {
1238 unsigned page_code :6; /* Page Code - Should be 0xf */
1239 unsigned reserved0 :1; /* Reserved */
1240 unsigned ps :1;
1241 __u8 page_length; /* Page Length - Should be 14 */
1242 unsigned reserved2 :6; /* Reserved */
1243 unsigned dcc :1; /* Data Compression Capable */
1244 unsigned dce :1; /* Data Compression Enable */
1245 unsigned reserved3 :5; /* Reserved */
1246 unsigned red :2; /* Report Exception on Decompression */
1247 unsigned dde :1; /* Data Decompression Enable */
1248 __u32 ca; /* Compression Algorithm */
1249 __u32 da; /* Decompression Algorithm */
1250 __u8 reserved[4]; /* Reserved */
1251 } idetape_data_compression_page_t;
1253 /*
1254 * The Medium Partition Page, as returned by the MODE SENSE packet command.
1255 */
1256 typedef struct {
1257 unsigned page_code :6; /* Page Code - Should be 0x11 */
1258 unsigned reserved1_6 :1; /* Reserved */
1259 unsigned ps :1;
1260 __u8 page_length; /* Page Length - Should be 6 */
1261 __u8 map; /* Maximum Additional Partitions - Should be 0 */
1262 __u8 apd; /* Additional Partitions Defined - Should be 0 */
1263 unsigned reserved4_012 :3; /* Reserved */
1264 unsigned psum :2; /* Should be 0 */
1265 unsigned idp :1; /* Should be 0 */
1266 unsigned sdp :1; /* Should be 0 */
1267 unsigned fdp :1; /* Fixed Data Partitions */
1268 __u8 mfr; /* Medium Format Recognition */
1269 __u8 reserved[2]; /* Reserved */
1270 } idetape_medium_partition_page_t;
1272 /*
1273 * Run time configurable parameters.
1274 */
1275 typedef struct {
1276 int dsc_rw_frequency;
1277 int dsc_media_access_frequency;
1278 int nr_stages;
1279 } idetape_config_t;
1281 /*
1282 * The variables below are used for the character device interface.
1283 * Additional state variables are defined in our ide_drive_t structure.
1284 */
1285 static struct ide_tape_obj * idetape_devs[MAX_HWIFS * MAX_DRIVES];
1287 #define ide_tape_f(file) ((file)->private_data)
1289 static struct ide_tape_obj *ide_tape_chrdev_get(unsigned int i)
1291 struct ide_tape_obj *tape = NULL;
1293 mutex_lock(&idetape_ref_mutex);
1294 tape = idetape_devs[i];
1295 if (tape)
1296 kref_get(&tape->kref);
1297 mutex_unlock(&idetape_ref_mutex);
1298 return tape;
1301 /*
1302 * Function declarations
1304 */
1305 static int idetape_chrdev_release (struct inode *inode, struct file *filp);
1306 static void idetape_write_release (ide_drive_t *drive, unsigned int minor);
1308 /*
1309 * Too bad. The drive wants to send us data which we are not ready to accept.
1310 * Just throw it away.
1311 */
1312 static void idetape_discard_data (ide_drive_t *drive, unsigned int bcount)
1314 while (bcount--)
1315 (void) HWIF(drive)->INB(IDE_DATA_REG);
1318 static void idetape_input_buffers (ide_drive_t *drive, idetape_pc_t *pc, unsigned int bcount)
1320 struct idetape_bh *bh = pc->bh;
1321 int count;
1323 while (bcount) {
1324 #if IDETAPE_DEBUG_BUGS
1325 if (bh == NULL) {
1326 printk(KERN_ERR "ide-tape: bh == NULL in "
1327 "idetape_input_buffers\n");
1328 idetape_discard_data(drive, bcount);
1329 return;
1331 #endif /* IDETAPE_DEBUG_BUGS */
1332 count = min((unsigned int)(bh->b_size - atomic_read(&bh->b_count)), bcount);
1333 HWIF(drive)->atapi_input_bytes(drive, bh->b_data + atomic_read(&bh->b_count), count);
1334 bcount -= count;
1335 atomic_add(count, &bh->b_count);
1336 if (atomic_read(&bh->b_count) == bh->b_size) {
1337 bh = bh->b_reqnext;
1338 if (bh)
1339 atomic_set(&bh->b_count, 0);
1342 pc->bh = bh;
1345 static void idetape_output_buffers (ide_drive_t *drive, idetape_pc_t *pc, unsigned int bcount)
1347 struct idetape_bh *bh = pc->bh;
1348 int count;
1350 while (bcount) {
1351 #if IDETAPE_DEBUG_BUGS
1352 if (bh == NULL) {
1353 printk(KERN_ERR "ide-tape: bh == NULL in "
1354 "idetape_output_buffers\n");
1355 return;
1357 #endif /* IDETAPE_DEBUG_BUGS */
1358 count = min((unsigned int)pc->b_count, (unsigned int)bcount);
1359 HWIF(drive)->atapi_output_bytes(drive, pc->b_data, count);
1360 bcount -= count;
1361 pc->b_data += count;
1362 pc->b_count -= count;
1363 if (!pc->b_count) {
1364 pc->bh = bh = bh->b_reqnext;
1365 if (bh) {
1366 pc->b_data = bh->b_data;
1367 pc->b_count = atomic_read(&bh->b_count);
1373 static void idetape_update_buffers (idetape_pc_t *pc)
1375 struct idetape_bh *bh = pc->bh;
1376 int count;
1377 unsigned int bcount = pc->actually_transferred;
1379 if (test_bit(PC_WRITING, &pc->flags))
1380 return;
1381 while (bcount) {
1382 #if IDETAPE_DEBUG_BUGS
1383 if (bh == NULL) {
1384 printk(KERN_ERR "ide-tape: bh == NULL in "
1385 "idetape_update_buffers\n");
1386 return;
1388 #endif /* IDETAPE_DEBUG_BUGS */
1389 count = min((unsigned int)bh->b_size, (unsigned int)bcount);
1390 atomic_set(&bh->b_count, count);
1391 if (atomic_read(&bh->b_count) == bh->b_size)
1392 bh = bh->b_reqnext;
1393 bcount -= count;
1395 pc->bh = bh;
1398 /*
1399 * idetape_next_pc_storage returns a pointer to a place in which we can
1400 * safely store a packet command, even though we intend to leave the
1401 * driver. A storage space for a maximum of IDETAPE_PC_STACK packet
1402 * commands is allocated at initialization time.
1403 */
1404 static idetape_pc_t *idetape_next_pc_storage (ide_drive_t *drive)
1406 idetape_tape_t *tape = drive->driver_data;
1408 #if IDETAPE_DEBUG_LOG
1409 if (tape->debug_level >= 5)
1410 printk(KERN_INFO "ide-tape: pc_stack_index=%d\n",
1411 tape->pc_stack_index);
1412 #endif /* IDETAPE_DEBUG_LOG */
1413 if (tape->pc_stack_index == IDETAPE_PC_STACK)
1414 tape->pc_stack_index=0;
1415 return (&tape->pc_stack[tape->pc_stack_index++]);
1418 /*
1419 * idetape_next_rq_storage is used along with idetape_next_pc_storage.
1420 * Since we queue packet commands in the request queue, we need to
1421 * allocate a request, along with the allocation of a packet command.
1422 */
1424 /**************************************************************
1425 * *
1426 * This should get fixed to use kmalloc(.., GFP_ATOMIC) *
1427 * followed later on by kfree(). -ml *
1428 * *
1429 **************************************************************/
1431 static struct request *idetape_next_rq_storage (ide_drive_t *drive)
1433 idetape_tape_t *tape = drive->driver_data;
1435 #if IDETAPE_DEBUG_LOG
1436 if (tape->debug_level >= 5)
1437 printk(KERN_INFO "ide-tape: rq_stack_index=%d\n",
1438 tape->rq_stack_index);
1439 #endif /* IDETAPE_DEBUG_LOG */
1440 if (tape->rq_stack_index == IDETAPE_PC_STACK)
1441 tape->rq_stack_index=0;
1442 return (&tape->rq_stack[tape->rq_stack_index++]);
1445 /*
1446 * idetape_init_pc initializes a packet command.
1447 */
1448 static void idetape_init_pc (idetape_pc_t *pc)
1450 memset(pc->c, 0, 12);
1451 pc->retries = 0;
1452 pc->flags = 0;
1453 pc->request_transfer = 0;
1454 pc->buffer = pc->pc_buffer;
1455 pc->buffer_size = IDETAPE_PC_BUFFER_SIZE;
1456 pc->bh = NULL;
1457 pc->b_data = NULL;
1460 /*
1461 * idetape_analyze_error is called on each failed packet command retry
1462 * to analyze the request sense. We currently do not utilize this
1463 * information.
1464 */
1465 static void idetape_analyze_error (ide_drive_t *drive, idetape_request_sense_result_t *result)
1467 idetape_tape_t *tape = drive->driver_data;
1468 idetape_pc_t *pc = tape->failed_pc;
1470 tape->sense = *result;
1471 tape->sense_key = result->sense_key;
1472 tape->asc = result->asc;
1473 tape->ascq = result->ascq;
1474 #if IDETAPE_DEBUG_LOG
1475 /*
1476 * Without debugging, we only log an error if we decided to
1477 * give up retrying.
1478 */
1479 if (tape->debug_level >= 1)
1480 printk(KERN_INFO "ide-tape: pc = %x, sense key = %x, "
1481 "asc = %x, ascq = %x\n",
1482 pc->c[0], result->sense_key,
1483 result->asc, result->ascq);
1484 #endif /* IDETAPE_DEBUG_LOG */
1486 /*
1487 * Correct pc->actually_transferred by asking the tape.
1488 */
1489 if (test_bit(PC_DMA_ERROR, &pc->flags)) {
1490 pc->actually_transferred = pc->request_transfer - tape->tape_block_size * ntohl(get_unaligned(&result->information));
1491 idetape_update_buffers(pc);
1494 /*
1495 * If error was the result of a zero-length read or write command,
1496 * with sense key=5, asc=0x22, ascq=0, let it slide. Some drives
1497 * (i.e. Seagate STT3401A Travan) don't support 0-length read/writes.
1498 */
1499 if ((pc->c[0] == IDETAPE_READ_CMD || pc->c[0] == IDETAPE_WRITE_CMD)
1500 && pc->c[4] == 0 && pc->c[3] == 0 && pc->c[2] == 0) { /* length==0 */
1501 if (result->sense_key == 5) {
1502 /* don't report an error, everything's ok */
1503 pc->error = 0;
1504 /* don't retry read/write */
1505 set_bit(PC_ABORT, &pc->flags);
1508 if (pc->c[0] == IDETAPE_READ_CMD && result->filemark) {
1509 pc->error = IDETAPE_ERROR_FILEMARK;
1510 set_bit(PC_ABORT, &pc->flags);
1512 if (pc->c[0] == IDETAPE_WRITE_CMD) {
1513 if (result->eom ||
1514 (result->sense_key == 0xd && result->asc == 0x0 &&
1515 result->ascq == 0x2)) {
1516 pc->error = IDETAPE_ERROR_EOD;
1517 set_bit(PC_ABORT, &pc->flags);
1520 if (pc->c[0] == IDETAPE_READ_CMD || pc->c[0] == IDETAPE_WRITE_CMD) {
1521 if (result->sense_key == 8) {
1522 pc->error = IDETAPE_ERROR_EOD;
1523 set_bit(PC_ABORT, &pc->flags);
1525 if (!test_bit(PC_ABORT, &pc->flags) &&
1526 pc->actually_transferred)
1527 pc->retries = IDETAPE_MAX_PC_RETRIES + 1;
1531 /*
1532 * idetape_active_next_stage will declare the next stage as "active".
1533 */
1534 static void idetape_active_next_stage (ide_drive_t *drive)
1536 idetape_tape_t *tape = drive->driver_data;
1537 idetape_stage_t *stage = tape->next_stage;
1538 struct request *rq = &stage->rq;
1540 #if IDETAPE_DEBUG_LOG
1541 if (tape->debug_level >= 4)
1542 printk(KERN_INFO "ide-tape: Reached idetape_active_next_stage\n");
1543 #endif /* IDETAPE_DEBUG_LOG */
1544 #if IDETAPE_DEBUG_BUGS
1545 if (stage == NULL) {
1546 printk(KERN_ERR "ide-tape: bug: Trying to activate a non existing stage\n");
1547 return;
1549 #endif /* IDETAPE_DEBUG_BUGS */
1551 rq->rq_disk = tape->disk;
1552 rq->buffer = NULL;
1553 rq->special = (void *)stage->bh;
1554 tape->active_data_request = rq;
1555 tape->active_stage = stage;
1556 tape->next_stage = stage->next;
1559 /*
1560 * idetape_increase_max_pipeline_stages is a part of the feedback
1561 * loop which tries to find the optimum number of stages. In the
1562 * feedback loop, we are starting from a minimum maximum number of
1563 * stages, and if we sense that the pipeline is empty, we try to
1564 * increase it, until we reach the user compile time memory limit.
1565 */
1566 static void idetape_increase_max_pipeline_stages (ide_drive_t *drive)
1568 idetape_tape_t *tape = drive->driver_data;
1569 int increase = (tape->max_pipeline - tape->min_pipeline) / 10;
1571 #if IDETAPE_DEBUG_LOG
1572 if (tape->debug_level >= 4)
1573 printk (KERN_INFO "ide-tape: Reached idetape_increase_max_pipeline_stages\n");
1574 #endif /* IDETAPE_DEBUG_LOG */
1576 tape->max_stages += max(increase, 1);
1577 tape->max_stages = max(tape->max_stages, tape->min_pipeline);
1578 tape->max_stages = min(tape->max_stages, tape->max_pipeline);
1581 /*
1582 * idetape_kfree_stage calls kfree to completely free a stage, along with
1583 * its related buffers.
1584 */
1585 static void __idetape_kfree_stage (idetape_stage_t *stage)
1587 struct idetape_bh *prev_bh, *bh = stage->bh;
1588 int size;
1590 while (bh != NULL) {
1591 if (bh->b_data != NULL) {
1592 size = (int) bh->b_size;
1593 while (size > 0) {
1594 free_page((unsigned long) bh->b_data);
1595 size -= PAGE_SIZE;
1596 bh->b_data += PAGE_SIZE;
1599 prev_bh = bh;
1600 bh = bh->b_reqnext;
1601 kfree(prev_bh);
1603 kfree(stage);
1606 static void idetape_kfree_stage (idetape_tape_t *tape, idetape_stage_t *stage)
1608 __idetape_kfree_stage(stage);
1611 /*
1612 * idetape_remove_stage_head removes tape->first_stage from the pipeline.
1613 * The caller should avoid race conditions.
1614 */
1615 static void idetape_remove_stage_head (ide_drive_t *drive)
1617 idetape_tape_t *tape = drive->driver_data;
1618 idetape_stage_t *stage;
1620 #if IDETAPE_DEBUG_LOG
1621 if (tape->debug_level >= 4)
1622 printk(KERN_INFO "ide-tape: Reached idetape_remove_stage_head\n");
1623 #endif /* IDETAPE_DEBUG_LOG */
1624 #if IDETAPE_DEBUG_BUGS
1625 if (tape->first_stage == NULL) {
1626 printk(KERN_ERR "ide-tape: bug: tape->first_stage is NULL\n");
1627 return;
1629 if (tape->active_stage == tape->first_stage) {
1630 printk(KERN_ERR "ide-tape: bug: Trying to free our active pipeline stage\n");
1631 return;
1633 #endif /* IDETAPE_DEBUG_BUGS */
1634 stage = tape->first_stage;
1635 tape->first_stage = stage->next;
1636 idetape_kfree_stage(tape, stage);
1637 tape->nr_stages--;
1638 if (tape->first_stage == NULL) {
1639 tape->last_stage = NULL;
1640 #if IDETAPE_DEBUG_BUGS
1641 if (tape->next_stage != NULL)
1642 printk(KERN_ERR "ide-tape: bug: tape->next_stage != NULL\n");
1643 if (tape->nr_stages)
1644 printk(KERN_ERR "ide-tape: bug: nr_stages should be 0 now\n");
1645 #endif /* IDETAPE_DEBUG_BUGS */
1649 /*
1650 * This will free all the pipeline stages starting from new_last_stage->next
1651 * to the end of the list, and point tape->last_stage to new_last_stage.
1652 */
1653 static void idetape_abort_pipeline(ide_drive_t *drive,
1654 idetape_stage_t *new_last_stage)
1656 idetape_tape_t *tape = drive->driver_data;
1657 idetape_stage_t *stage = new_last_stage->next;
1658 idetape_stage_t *nstage;
1660 #if IDETAPE_DEBUG_LOG
1661 if (tape->debug_level >= 4)
1662 printk(KERN_INFO "ide-tape: %s: idetape_abort_pipeline called\n", tape->name);
1663 #endif
1664 while (stage) {
1665 nstage = stage->next;
1666 idetape_kfree_stage(tape, stage);
1667 --tape->nr_stages;
1668 --tape->nr_pending_stages;
1669 stage = nstage;
1671 if (new_last_stage)
1672 new_last_stage->next = NULL;
1673 tape->last_stage = new_last_stage;
1674 tape->next_stage = NULL;
1677 /*
1678 * idetape_end_request is used to finish servicing a request, and to
1679 * insert a pending pipeline request into the main device queue.
1680 */
1681 static int idetape_end_request(ide_drive_t *drive, int uptodate, int nr_sects)
1683 struct request *rq = HWGROUP(drive)->rq;
1684 idetape_tape_t *tape = drive->driver_data;
1685 unsigned long flags;
1686 int error;
1687 int remove_stage = 0;
1688 idetape_stage_t *active_stage;
1690 #if IDETAPE_DEBUG_LOG
1691 if (tape->debug_level >= 4)
1692 printk(KERN_INFO "ide-tape: Reached idetape_end_request\n");
1693 #endif /* IDETAPE_DEBUG_LOG */
1695 switch (uptodate) {
1696 case 0: error = IDETAPE_ERROR_GENERAL; break;
1697 case 1: error = 0; break;
1698 default: error = uptodate;
1700 rq->errors = error;
1701 if (error)
1702 tape->failed_pc = NULL;
1704 spin_lock_irqsave(&tape->spinlock, flags);
1706 /* The request was a pipelined data transfer request */
1707 if (tape->active_data_request == rq) {
1708 active_stage = tape->active_stage;
1709 tape->active_stage = NULL;
1710 tape->active_data_request = NULL;
1711 tape->nr_pending_stages--;
1712 if (rq->cmd[0] & REQ_IDETAPE_WRITE) {
1713 remove_stage = 1;
1714 if (error) {
1715 set_bit(IDETAPE_PIPELINE_ERROR, &tape->flags);
1716 if (error == IDETAPE_ERROR_EOD)
1717 idetape_abort_pipeline(drive, active_stage);
1719 } else if (rq->cmd[0] & REQ_IDETAPE_READ) {
1720 if (error == IDETAPE_ERROR_EOD) {
1721 set_bit(IDETAPE_PIPELINE_ERROR, &tape->flags);
1722 idetape_abort_pipeline(drive, active_stage);
1725 if (tape->next_stage != NULL) {
1726 idetape_active_next_stage(drive);
1728 /*
1729 * Insert the next request into the request queue.
1730 */
1731 (void) ide_do_drive_cmd(drive, tape->active_data_request, ide_end);
1732 } else if (!error) {
1733 idetape_increase_max_pipeline_stages(drive);
1736 ide_end_drive_cmd(drive, 0, 0);
1737 // blkdev_dequeue_request(rq);
1738 // drive->rq = NULL;
1739 // end_that_request_last(rq);
1741 if (remove_stage)
1742 idetape_remove_stage_head(drive);
1743 if (tape->active_data_request == NULL)
1744 clear_bit(IDETAPE_PIPELINE_ACTIVE, &tape->flags);
1745 spin_unlock_irqrestore(&tape->spinlock, flags);
1746 return 0;
1749 static ide_startstop_t idetape_request_sense_callback (ide_drive_t *drive)
1751 idetape_tape_t *tape = drive->driver_data;
1753 #if IDETAPE_DEBUG_LOG
1754 if (tape->debug_level >= 4)
1755 printk(KERN_INFO "ide-tape: Reached idetape_request_sense_callback\n");
1756 #endif /* IDETAPE_DEBUG_LOG */
1757 if (!tape->pc->error) {
1758 idetape_analyze_error(drive, (idetape_request_sense_result_t *) tape->pc->buffer);
1759 idetape_end_request(drive, 1, 0);
1760 } else {
1761 printk(KERN_ERR "ide-tape: Error in REQUEST SENSE itself - Aborting request!\n");
1762 idetape_end_request(drive, 0, 0);
1764 return ide_stopped;
1767 static void idetape_create_request_sense_cmd (idetape_pc_t *pc)
1769 idetape_init_pc(pc);
1770 pc->c[0] = IDETAPE_REQUEST_SENSE_CMD;
1771 pc->c[4] = 20;
1772 pc->request_transfer = 20;
1773 pc->callback = &idetape_request_sense_callback;
1776 static void idetape_init_rq(struct request *rq, u8 cmd)
1778 memset(rq, 0, sizeof(*rq));
1779 rq->flags = REQ_SPECIAL;
1780 rq->cmd[0] = cmd;
1783 /*
1784 * idetape_queue_pc_head generates a new packet command request in front
1785 * of the request queue, before the current request, so that it will be
1786 * processed immediately, on the next pass through the driver.
1788 * idetape_queue_pc_head is called from the request handling part of
1789 * the driver (the "bottom" part). Safe storage for the request should
1790 * be allocated with idetape_next_pc_storage and idetape_next_rq_storage
1791 * before calling idetape_queue_pc_head.
1793 * Memory for those requests is pre-allocated at initialization time, and
1794 * is limited to IDETAPE_PC_STACK requests. We assume that we have enough
1795 * space for the maximum possible number of inter-dependent packet commands.
1797 * The higher level of the driver - The ioctl handler and the character
1798 * device handling functions should queue request to the lower level part
1799 * and wait for their completion using idetape_queue_pc_tail or
1800 * idetape_queue_rw_tail.
1801 */
1802 static void idetape_queue_pc_head (ide_drive_t *drive, idetape_pc_t *pc,struct request *rq)
1804 struct ide_tape_obj *tape = drive->driver_data;
1806 idetape_init_rq(rq, REQ_IDETAPE_PC1);
1807 rq->buffer = (char *) pc;
1808 rq->rq_disk = tape->disk;
1809 (void) ide_do_drive_cmd(drive, rq, ide_preempt);
1812 /*
1813 * idetape_retry_pc is called when an error was detected during the
1814 * last packet command. We queue a request sense packet command in
1815 * the head of the request list.
1816 */
1817 static ide_startstop_t idetape_retry_pc (ide_drive_t *drive)
1819 idetape_tape_t *tape = drive->driver_data;
1820 idetape_pc_t *pc;
1821 struct request *rq;
1822 atapi_error_t error;
1824 error.all = HWIF(drive)->INB(IDE_ERROR_REG);
1825 pc = idetape_next_pc_storage(drive);
1826 rq = idetape_next_rq_storage(drive);
1827 idetape_create_request_sense_cmd(pc);
1828 set_bit(IDETAPE_IGNORE_DSC, &tape->flags);
1829 idetape_queue_pc_head(drive, pc, rq);
1830 return ide_stopped;
1833 /*
1834 * idetape_postpone_request postpones the current request so that
1835 * ide.c will be able to service requests from another device on
1836 * the same hwgroup while we are polling for DSC.
1837 */
1838 static void idetape_postpone_request (ide_drive_t *drive)
1840 idetape_tape_t *tape = drive->driver_data;
1842 #if IDETAPE_DEBUG_LOG
1843 if (tape->debug_level >= 4)
1844 printk(KERN_INFO "ide-tape: idetape_postpone_request\n");
1845 #endif
1846 tape->postponed_rq = HWGROUP(drive)->rq;
1847 ide_stall_queue(drive, tape->dsc_polling_frequency);
1850 /*
1851 * idetape_pc_intr is the usual interrupt handler which will be called
1852 * during a packet command. We will transfer some of the data (as
1853 * requested by the drive) and will re-point interrupt handler to us.
1854 * When data transfer is finished, we will act according to the
1855 * algorithm described before idetape_issue_packet_command.
1857 */
1858 static ide_startstop_t idetape_pc_intr (ide_drive_t *drive)
1860 ide_hwif_t *hwif = drive->hwif;
1861 idetape_tape_t *tape = drive->driver_data;
1862 atapi_status_t status;
1863 atapi_bcount_t bcount;
1864 atapi_ireason_t ireason;
1865 idetape_pc_t *pc = tape->pc;
1867 unsigned int temp;
1868 #if SIMULATE_ERRORS
1869 static int error_sim_count = 0;
1870 #endif
1872 #if IDETAPE_DEBUG_LOG
1873 if (tape->debug_level >= 4)
1874 printk(KERN_INFO "ide-tape: Reached idetape_pc_intr "
1875 "interrupt handler\n");
1876 #endif /* IDETAPE_DEBUG_LOG */
1878 /* Clear the interrupt */
1879 status.all = HWIF(drive)->INB(IDE_STATUS_REG);
1881 if (test_bit(PC_DMA_IN_PROGRESS, &pc->flags)) {
1882 if (HWIF(drive)->ide_dma_end(drive) || status.b.check) {
1883 /*
1884 * A DMA error is sometimes expected. For example,
1885 * if the tape is crossing a filemark during a
1886 * READ command, it will issue an irq and position
1887 * itself before the filemark, so that only a partial
1888 * data transfer will occur (which causes the DMA
1889 * error). In that case, we will later ask the tape
1890 * how much bytes of the original request were
1891 * actually transferred (we can't receive that
1892 * information from the DMA engine on most chipsets).
1893 */
1895 /*
1896 * On the contrary, a DMA error is never expected;
1897 * it usually indicates a hardware error or abort.
1898 * If the tape crosses a filemark during a READ
1899 * command, it will issue an irq and position itself
1900 * after the filemark (not before). Only a partial
1901 * data transfer will occur, but no DMA error.
1902 * (AS, 19 Apr 2001)
1903 */
1904 set_bit(PC_DMA_ERROR, &pc->flags);
1905 } else {
1906 pc->actually_transferred = pc->request_transfer;
1907 idetape_update_buffers(pc);
1909 #if IDETAPE_DEBUG_LOG
1910 if (tape->debug_level >= 4)
1911 printk(KERN_INFO "ide-tape: DMA finished\n");
1912 #endif /* IDETAPE_DEBUG_LOG */
1915 /* No more interrupts */
1916 if (!status.b.drq) {
1917 #if IDETAPE_DEBUG_LOG
1918 if (tape->debug_level >= 2)
1919 printk(KERN_INFO "ide-tape: Packet command completed, %d bytes transferred\n", pc->actually_transferred);
1920 #endif /* IDETAPE_DEBUG_LOG */
1921 clear_bit(PC_DMA_IN_PROGRESS, &pc->flags);
1923 local_irq_enable();
1925 #if SIMULATE_ERRORS
1926 if ((pc->c[0] == IDETAPE_WRITE_CMD ||
1927 pc->c[0] == IDETAPE_READ_CMD) &&
1928 (++error_sim_count % 100) == 0) {
1929 printk(KERN_INFO "ide-tape: %s: simulating error\n",
1930 tape->name);
1931 status.b.check = 1;
1933 #endif
1934 if (status.b.check && pc->c[0] == IDETAPE_REQUEST_SENSE_CMD)
1935 status.b.check = 0;
1936 if (status.b.check || test_bit(PC_DMA_ERROR, &pc->flags)) { /* Error detected */
1937 #if IDETAPE_DEBUG_LOG
1938 if (tape->debug_level >= 1)
1939 printk(KERN_INFO "ide-tape: %s: I/O error\n",
1940 tape->name);
1941 #endif /* IDETAPE_DEBUG_LOG */
1942 if (pc->c[0] == IDETAPE_REQUEST_SENSE_CMD) {
1943 printk(KERN_ERR "ide-tape: I/O error in request sense command\n");
1944 return ide_do_reset(drive);
1946 #if IDETAPE_DEBUG_LOG
1947 if (tape->debug_level >= 1)
1948 printk(KERN_INFO "ide-tape: [cmd %x]: check condition\n", pc->c[0]);
1949 #endif
1950 /* Retry operation */
1951 return idetape_retry_pc(drive);
1953 pc->error = 0;
1954 if (test_bit(PC_WAIT_FOR_DSC, &pc->flags) &&
1955 !status.b.dsc) {
1956 /* Media access command */
1957 tape->dsc_polling_start = jiffies;
1958 tape->dsc_polling_frequency = IDETAPE_DSC_MA_FAST;
1959 tape->dsc_timeout = jiffies + IDETAPE_DSC_MA_TIMEOUT;
1960 /* Allow ide.c to handle other requests */
1961 idetape_postpone_request(drive);
1962 return ide_stopped;
1964 if (tape->failed_pc == pc)
1965 tape->failed_pc = NULL;
1966 /* Command finished - Call the callback function */
1967 return pc->callback(drive);
1969 if (test_and_clear_bit(PC_DMA_IN_PROGRESS, &pc->flags)) {
1970 printk(KERN_ERR "ide-tape: The tape wants to issue more "
1971 "interrupts in DMA mode\n");
1972 printk(KERN_ERR "ide-tape: DMA disabled, reverting to PIO\n");
1973 (void)__ide_dma_off(drive);
1974 return ide_do_reset(drive);
1976 /* Get the number of bytes to transfer on this interrupt. */
1977 bcount.b.high = hwif->INB(IDE_BCOUNTH_REG);
1978 bcount.b.low = hwif->INB(IDE_BCOUNTL_REG);
1980 ireason.all = hwif->INB(IDE_IREASON_REG);
1982 if (ireason.b.cod) {
1983 printk(KERN_ERR "ide-tape: CoD != 0 in idetape_pc_intr\n");
1984 return ide_do_reset(drive);
1986 if (ireason.b.io == test_bit(PC_WRITING, &pc->flags)) {
1987 /* Hopefully, we will never get here */
1988 printk(KERN_ERR "ide-tape: We wanted to %s, ",
1989 ireason.b.io ? "Write":"Read");
1990 printk(KERN_ERR "ide-tape: but the tape wants us to %s !\n",
1991 ireason.b.io ? "Read":"Write");
1992 return ide_do_reset(drive);
1994 if (!test_bit(PC_WRITING, &pc->flags)) {
1995 /* Reading - Check that we have enough space */
1996 temp = pc->actually_transferred + bcount.all;
1997 if (temp > pc->request_transfer) {
1998 if (temp > pc->buffer_size) {
1999 printk(KERN_ERR "ide-tape: The tape wants to send us more data than expected - discarding data\n");
2000 idetape_discard_data(drive, bcount.all);
2001 ide_set_handler(drive, &idetape_pc_intr, IDETAPE_WAIT_CMD, NULL);
2002 return ide_started;
2004 #if IDETAPE_DEBUG_LOG
2005 if (tape->debug_level >= 2)
2006 printk(KERN_NOTICE "ide-tape: The tape wants to send us more data than expected - allowing transfer\n");
2007 #endif /* IDETAPE_DEBUG_LOG */
2010 if (test_bit(PC_WRITING, &pc->flags)) {
2011 if (pc->bh != NULL)
2012 idetape_output_buffers(drive, pc, bcount.all);
2013 else
2014 /* Write the current buffer */
2015 HWIF(drive)->atapi_output_bytes(drive, pc->current_position, bcount.all);
2016 } else {
2017 if (pc->bh != NULL)
2018 idetape_input_buffers(drive, pc, bcount.all);
2019 else
2020 /* Read the current buffer */
2021 HWIF(drive)->atapi_input_bytes(drive, pc->current_position, bcount.all);
2023 /* Update the current position */
2024 pc->actually_transferred += bcount.all;
2025 pc->current_position += bcount.all;
2026 #if IDETAPE_DEBUG_LOG
2027 if (tape->debug_level >= 2)
2028 printk(KERN_INFO "ide-tape: [cmd %x] transferred %d bytes on that interrupt\n", pc->c[0], bcount.all);
2029 #endif
2030 /* And set the interrupt handler again */
2031 ide_set_handler(drive, &idetape_pc_intr, IDETAPE_WAIT_CMD, NULL);
2032 return ide_started;
2035 /*
2036 * Packet Command Interface
2038 * The current Packet Command is available in tape->pc, and will not
2039 * change until we finish handling it. Each packet command is associated
2040 * with a callback function that will be called when the command is
2041 * finished.
2043 * The handling will be done in three stages:
2045 * 1. idetape_issue_packet_command will send the packet command to the
2046 * drive, and will set the interrupt handler to idetape_pc_intr.
2048 * 2. On each interrupt, idetape_pc_intr will be called. This step
2049 * will be repeated until the device signals us that no more
2050 * interrupts will be issued.
2052 * 3. ATAPI Tape media access commands have immediate status with a
2053 * delayed process. In case of a successful initiation of a
2054 * media access packet command, the DSC bit will be set when the
2055 * actual execution of the command is finished.
2056 * Since the tape drive will not issue an interrupt, we have to
2057 * poll for this event. In this case, we define the request as
2058 * "low priority request" by setting rq_status to
2059 * IDETAPE_RQ_POSTPONED, set a timer to poll for DSC and exit
2060 * the driver.
2062 * ide.c will then give higher priority to requests which
2063 * originate from the other device, until will change rq_status
2064 * to RQ_ACTIVE.
2066 * 4. When the packet command is finished, it will be checked for errors.
2068 * 5. In case an error was found, we queue a request sense packet
2069 * command in front of the request queue and retry the operation
2070 * up to IDETAPE_MAX_PC_RETRIES times.
2072 * 6. In case no error was found, or we decided to give up and not
2073 * to retry again, the callback function will be called and then
2074 * we will handle the next request.
2076 */
2077 static ide_startstop_t idetape_transfer_pc(ide_drive_t *drive)
2079 ide_hwif_t *hwif = drive->hwif;
2080 idetape_tape_t *tape = drive->driver_data;
2081 idetape_pc_t *pc = tape->pc;
2082 atapi_ireason_t ireason;
2083 int retries = 100;
2084 ide_startstop_t startstop;
2086 if (ide_wait_stat(&startstop,drive,DRQ_STAT,BUSY_STAT,WAIT_READY)) {
2087 printk(KERN_ERR "ide-tape: Strange, packet command initiated yet DRQ isn't asserted\n");
2088 return startstop;
2090 ireason.all = hwif->INB(IDE_IREASON_REG);
2091 while (retries-- && (!ireason.b.cod || ireason.b.io)) {
2092 printk(KERN_ERR "ide-tape: (IO,CoD != (0,1) while issuing "
2093 "a packet command, retrying\n");
2094 udelay(100);
2095 ireason.all = hwif->INB(IDE_IREASON_REG);
2096 if (retries == 0) {
2097 printk(KERN_ERR "ide-tape: (IO,CoD != (0,1) while "
2098 "issuing a packet command, ignoring\n");
2099 ireason.b.cod = 1;
2100 ireason.b.io = 0;
2103 if (!ireason.b.cod || ireason.b.io) {
2104 printk(KERN_ERR "ide-tape: (IO,CoD) != (0,1) while issuing "
2105 "a packet command\n");
2106 return ide_do_reset(drive);
2108 /* Set the interrupt routine */
2109 ide_set_handler(drive, &idetape_pc_intr, IDETAPE_WAIT_CMD, NULL);
2110 #ifdef CONFIG_BLK_DEV_IDEDMA
2111 /* Begin DMA, if necessary */
2112 if (test_bit(PC_DMA_IN_PROGRESS, &pc->flags))
2113 hwif->dma_start(drive);
2114 #endif
2115 /* Send the actual packet */
2116 HWIF(drive)->atapi_output_bytes(drive, pc->c, 12);
2117 return ide_started;
2120 static ide_startstop_t idetape_issue_packet_command (ide_drive_t *drive, idetape_pc_t *pc)
2122 ide_hwif_t *hwif = drive->hwif;
2123 idetape_tape_t *tape = drive->driver_data;
2124 atapi_bcount_t bcount;
2125 int dma_ok = 0;
2127 #if IDETAPE_DEBUG_BUGS
2128 if (tape->pc->c[0] == IDETAPE_REQUEST_SENSE_CMD &&
2129 pc->c[0] == IDETAPE_REQUEST_SENSE_CMD) {
2130 printk(KERN_ERR "ide-tape: possible ide-tape.c bug - "
2131 "Two request sense in serial were issued\n");
2133 #endif /* IDETAPE_DEBUG_BUGS */
2135 if (tape->failed_pc == NULL && pc->c[0] != IDETAPE_REQUEST_SENSE_CMD)
2136 tape->failed_pc = pc;
2137 /* Set the current packet command */
2138 tape->pc = pc;
2140 if (pc->retries > IDETAPE_MAX_PC_RETRIES ||
2141 test_bit(PC_ABORT, &pc->flags)) {
2142 /*
2143 * We will "abort" retrying a packet command in case
2144 * a legitimate error code was received (crossing a
2145 * filemark, or end of the media, for example).
2146 */
2147 if (!test_bit(PC_ABORT, &pc->flags)) {
2148 if (!(pc->c[0] == IDETAPE_TEST_UNIT_READY_CMD &&
2149 tape->sense_key == 2 && tape->asc == 4 &&
2150 (tape->ascq == 1 || tape->ascq == 8))) {
2151 printk(KERN_ERR "ide-tape: %s: I/O error, "
2152 "pc = %2x, key = %2x, "
2153 "asc = %2x, ascq = %2x\n",
2154 tape->name, pc->c[0],
2155 tape->sense_key, tape->asc,
2156 tape->ascq);
2158 /* Giving up */
2159 pc->error = IDETAPE_ERROR_GENERAL;
2161 tape->failed_pc = NULL;
2162 return pc->callback(drive);
2164 #if IDETAPE_DEBUG_LOG
2165 if (tape->debug_level >= 2)
2166 printk(KERN_INFO "ide-tape: Retry number - %d, cmd = %02X\n", pc->retries, pc->c[0]);
2167 #endif /* IDETAPE_DEBUG_LOG */
2169 pc->retries++;
2170 /* We haven't transferred any data yet */
2171 pc->actually_transferred = 0;
2172 pc->current_position = pc->buffer;
2173 /* Request to transfer the entire buffer at once */
2174 bcount.all = pc->request_transfer;
2176 if (test_and_clear_bit(PC_DMA_ERROR, &pc->flags)) {
2177 printk(KERN_WARNING "ide-tape: DMA disabled, "
2178 "reverting to PIO\n");
2179 (void)__ide_dma_off(drive);
2181 if (test_bit(PC_DMA_RECOMMENDED, &pc->flags) && drive->using_dma)
2182 dma_ok = !hwif->dma_setup(drive);
2184 if (IDE_CONTROL_REG)
2185 hwif->OUTB(drive->ctl, IDE_CONTROL_REG);
2186 hwif->OUTB(dma_ok ? 1 : 0, IDE_FEATURE_REG); /* Use PIO/DMA */
2187 hwif->OUTB(bcount.b.high, IDE_BCOUNTH_REG);
2188 hwif->OUTB(bcount.b.low, IDE_BCOUNTL_REG);
2189 hwif->OUTB(drive->select.all, IDE_SELECT_REG);
2190 if (dma_ok) /* Will begin DMA later */
2191 set_bit(PC_DMA_IN_PROGRESS, &pc->flags);
2192 if (test_bit(IDETAPE_DRQ_INTERRUPT, &tape->flags)) {
2193 ide_set_handler(drive, &idetape_transfer_pc, IDETAPE_WAIT_CMD, NULL);
2194 hwif->OUTB(WIN_PACKETCMD, IDE_COMMAND_REG);
2195 return ide_started;
2196 } else {
2197 hwif->OUTB(WIN_PACKETCMD, IDE_COMMAND_REG);
2198 return idetape_transfer_pc(drive);
2202 /*
2203 * General packet command callback function.
2204 */
2205 static ide_startstop_t idetape_pc_callback (ide_drive_t *drive)
2207 idetape_tape_t *tape = drive->driver_data;
2209 #if IDETAPE_DEBUG_LOG
2210 if (tape->debug_level >= 4)
2211 printk(KERN_INFO "ide-tape: Reached idetape_pc_callback\n");
2212 #endif /* IDETAPE_DEBUG_LOG */
2214 idetape_end_request(drive, tape->pc->error ? 0 : 1, 0);
2215 return ide_stopped;
2218 /*
2219 * A mode sense command is used to "sense" tape parameters.
2220 */
2221 static void idetape_create_mode_sense_cmd (idetape_pc_t *pc, u8 page_code)
2223 idetape_init_pc(pc);
2224 pc->c[0] = IDETAPE_MODE_SENSE_CMD;
2225 if (page_code != IDETAPE_BLOCK_DESCRIPTOR)
2226 pc->c[1] = 8; /* DBD = 1 - Don't return block descriptors */
2227 pc->c[2] = page_code;
2228 /*
2229 * Changed pc->c[3] to 0 (255 will at best return unused info).
2231 * For SCSI this byte is defined as subpage instead of high byte
2232 * of length and some IDE drives seem to interpret it this way
2233 * and return an error when 255 is used.
2234 */
2235 pc->c[3] = 0;
2236 pc->c[4] = 255; /* (We will just discard data in that case) */
2237 if (page_code == IDETAPE_BLOCK_DESCRIPTOR)
2238 pc->request_transfer = 12;
2239 else if (page_code == IDETAPE_CAPABILITIES_PAGE)
2240 pc->request_transfer = 24;
2241 else
2242 pc->request_transfer = 50;
2243 pc->callback = &idetape_pc_callback;
2246 static void calculate_speeds(ide_drive_t *drive)
2248 idetape_tape_t *tape = drive->driver_data;
2249 int full = 125, empty = 75;
2251 if (time_after(jiffies, tape->controlled_pipeline_head_time + 120 * HZ)) {
2252 tape->controlled_previous_pipeline_head = tape->controlled_last_pipeline_head;
2253 tape->controlled_previous_head_time = tape->controlled_pipeline_head_time;
2254 tape->controlled_last_pipeline_head = tape->pipeline_head;
2255 tape->controlled_pipeline_head_time = jiffies;
2257 if (time_after(jiffies, tape->controlled_pipeline_head_time + 60 * HZ))
2258 tape->controlled_pipeline_head_speed = (tape->pipeline_head - tape->controlled_last_pipeline_head) * 32 * HZ / (jiffies - tape->controlled_pipeline_head_time);
2259 else if (time_after(jiffies, tape->controlled_previous_head_time))
2260 tape->controlled_pipeline_head_speed = (tape->pipeline_head - tape->controlled_previous_pipeline_head) * 32 * HZ / (jiffies - tape->controlled_previous_head_time);
2262 if (tape->nr_pending_stages < tape->max_stages /*- 1 */) {
2263 /* -1 for read mode error recovery */
2264 if (time_after(jiffies, tape->uncontrolled_previous_head_time + 10 * HZ)) {
2265 tape->uncontrolled_pipeline_head_time = jiffies;
2266 tape->uncontrolled_pipeline_head_speed = (tape->pipeline_head - tape->uncontrolled_previous_pipeline_head) * 32 * HZ / (jiffies - tape->uncontrolled_previous_head_time);
2268 } else {
2269 tape->uncontrolled_previous_head_time = jiffies;
2270 tape->uncontrolled_previous_pipeline_head = tape->pipeline_head;
2271 if (time_after(jiffies, tape->uncontrolled_pipeline_head_time + 30 * HZ)) {
2272 tape->uncontrolled_pipeline_head_time = jiffies;
2275 tape->pipeline_head_speed = max(tape->uncontrolled_pipeline_head_speed, tape->controlled_pipeline_head_speed);
2276 if (tape->speed_control == 0) {
2277 tape->max_insert_speed = 5000;
2278 } else if (tape->speed_control == 1) {
2279 if (tape->nr_pending_stages >= tape->max_stages / 2)
2280 tape->max_insert_speed = tape->pipeline_head_speed +
2281 (1100 - tape->pipeline_head_speed) * 2 * (tape->nr_pending_stages - tape->max_stages / 2) / tape->max_stages;
2282 else
2283 tape->max_insert_speed = 500 +
2284 (tape->pipeline_head_speed - 500) * 2 * tape->nr_pending_stages / tape->max_stages;
2285 if (tape->nr_pending_stages >= tape->max_stages * 99 / 100)
2286 tape->max_insert_speed = 5000;
2287 } else if (tape->speed_control == 2) {
2288 tape->max_insert_speed = tape->pipeline_head_speed * empty / 100 +
2289 (tape->pipeline_head_speed * full / 100 - tape->pipeline_head_speed * empty / 100) * tape->nr_pending_stages / tape->max_stages;
2290 } else
2291 tape->max_insert_speed = tape->speed_control;
2292 tape->max_insert_speed = max(tape->max_insert_speed, 500);
2295 static ide_startstop_t idetape_media_access_finished (ide_drive_t *drive)
2297 idetape_tape_t *tape = drive->driver_data;
2298 idetape_pc_t *pc = tape->pc;
2299 atapi_status_t status;
2301 status.all = HWIF(drive)->INB(IDE_STATUS_REG);
2302 if (status.b.dsc) {
2303 if (status.b.check) {
2304 /* Error detected */
2305 if (pc->c[0] != IDETAPE_TEST_UNIT_READY_CMD)
2306 printk(KERN_ERR "ide-tape: %s: I/O error, ",
2307 tape->name);
2308 /* Retry operation */
2309 return idetape_retry_pc(drive);
2311 pc->error = 0;
2312 if (tape->failed_pc == pc)
2313 tape->failed_pc = NULL;
2314 } else {
2315 pc->error = IDETAPE_ERROR_GENERAL;
2316 tape->failed_pc = NULL;
2318 return pc->callback(drive);
2321 static ide_startstop_t idetape_rw_callback (ide_drive_t *drive)
2323 idetape_tape_t *tape = drive->driver_data;
2324 struct request *rq = HWGROUP(drive)->rq;
2325 int blocks = tape->pc->actually_transferred / tape->tape_block_size;
2327 tape->avg_size += blocks * tape->tape_block_size;
2328 tape->insert_size += blocks * tape->tape_block_size;
2329 if (tape->insert_size > 1024 * 1024)
2330 tape->measure_insert_time = 1;
2331 if (tape->measure_insert_time) {
2332 tape->measure_insert_time = 0;
2333 tape->insert_time = jiffies;
2334 tape->insert_size = 0;
2336 if (time_after(jiffies, tape->insert_time))
2337 tape->insert_speed = tape->insert_size / 1024 * HZ / (jiffies - tape->insert_time);
2338 if (time_after_eq(jiffies, tape->avg_time + HZ)) {
2339 tape->avg_speed = tape->avg_size * HZ / (jiffies - tape->avg_time) / 1024;
2340 tape->avg_size = 0;
2341 tape->avg_time = jiffies;
2344 #if IDETAPE_DEBUG_LOG
2345 if (tape->debug_level >= 4)
2346 printk(KERN_INFO "ide-tape: Reached idetape_rw_callback\n");
2347 #endif /* IDETAPE_DEBUG_LOG */
2349 tape->first_frame_position += blocks;
2350 rq->current_nr_sectors -= blocks;
2352 if (!tape->pc->error)
2353 idetape_end_request(drive, 1, 0);
2354 else
2355 idetape_end_request(drive, tape->pc->error, 0);
2356 return ide_stopped;
2359 static void idetape_create_read_cmd(idetape_tape_t *tape, idetape_pc_t *pc, unsigned int length, struct idetape_bh *bh)
2361 idetape_init_pc(pc);
2362 pc->c[0] = IDETAPE_READ_CMD;
2363 put_unaligned(htonl(length), (unsigned int *) &pc->c[1]);
2364 pc->c[1] = 1;
2365 pc->callback = &idetape_rw_callback;
2366 pc->bh = bh;
2367 atomic_set(&bh->b_count, 0);
2368 pc->buffer = NULL;
2369 pc->request_transfer = pc->buffer_size = length * tape->tape_block_size;
2370 if (pc->request_transfer == tape->stage_size)
2371 set_bit(PC_DMA_RECOMMENDED, &pc->flags);
2374 static void idetape_create_read_buffer_cmd(idetape_tape_t *tape, idetape_pc_t *pc, unsigned int length, struct idetape_bh *bh)
2376 int size = 32768;
2377 struct idetape_bh *p = bh;
2379 idetape_init_pc(pc);
2380 pc->c[0] = IDETAPE_READ_BUFFER_CMD;
2381 pc->c[1] = IDETAPE_RETRIEVE_FAULTY_BLOCK;
2382 pc->c[7] = size >> 8;
2383 pc->c[8] = size & 0xff;
2384 pc->callback = &idetape_pc_callback;
2385 pc->bh = bh;
2386 atomic_set(&bh->b_count, 0);
2387 pc->buffer = NULL;
2388 while (p) {
2389 atomic_set(&p->b_count, 0);
2390 p = p->b_reqnext;
2392 pc->request_transfer = pc->buffer_size = size;
2395 static void idetape_create_write_cmd(idetape_tape_t *tape, idetape_pc_t *pc, unsigned int length, struct idetape_bh *bh)
2397 idetape_init_pc(pc);
2398 pc->c[0] = IDETAPE_WRITE_CMD;
2399 put_unaligned(htonl(length), (unsigned int *) &pc->c[1]);
2400 pc->c[1] = 1;
2401 pc->callback = &idetape_rw_callback;
2402 set_bit(PC_WRITING, &pc->flags);
2403 pc->bh = bh;
2404 pc->b_data = bh->b_data;
2405 pc->b_count = atomic_read(&bh->b_count);
2406 pc->buffer = NULL;
2407 pc->request_transfer = pc->buffer_size = length * tape->tape_block_size;
2408 if (pc->request_transfer == tape->stage_size)
2409 set_bit(PC_DMA_RECOMMENDED, &pc->flags);
2412 /*
2413 * idetape_do_request is our request handling function.
2414 */
2415 static ide_startstop_t idetape_do_request(ide_drive_t *drive,
2416 struct request *rq, sector_t block)
2418 idetape_tape_t *tape = drive->driver_data;
2419 idetape_pc_t *pc = NULL;
2420 struct request *postponed_rq = tape->postponed_rq;
2421 atapi_status_t status;
2423 #if IDETAPE_DEBUG_LOG
2424 #if 0
2425 if (tape->debug_level >= 5)
2426 printk(KERN_INFO "ide-tape: rq_status: %d, "
2427 "dev: %s, cmd: %ld, errors: %d\n", rq->rq_status,
2428 rq->rq_disk->disk_name, rq->cmd[0], rq->errors);
2429 #endif
2430 if (tape->debug_level >= 2)
2431 printk(KERN_INFO "ide-tape: sector: %ld, "
2432 "nr_sectors: %ld, current_nr_sectors: %d\n",
2433 rq->sector, rq->nr_sectors, rq->current_nr_sectors);
2434 #endif /* IDETAPE_DEBUG_LOG */
2436 if ((rq->flags & REQ_SPECIAL) == 0) {
2437 /*
2438 * We do not support buffer cache originated requests.
2439 */
2440 printk(KERN_NOTICE "ide-tape: %s: Unsupported request in "
2441 "request queue (%ld)\n", drive->name, rq->flags);
2442 ide_end_request(drive, 0, 0);
2443 return ide_stopped;
2446 /*
2447 * Retry a failed packet command
2448 */
2449 if (tape->failed_pc != NULL &&
2450 tape->pc->c[0] == IDETAPE_REQUEST_SENSE_CMD) {
2451 return idetape_issue_packet_command(drive, tape->failed_pc);
2453 #if IDETAPE_DEBUG_BUGS
2454 if (postponed_rq != NULL)
2455 if (rq != postponed_rq) {
2456 printk(KERN_ERR "ide-tape: ide-tape.c bug - "
2457 "Two DSC requests were queued\n");
2458 idetape_end_request(drive, 0, 0);
2459 return ide_stopped;
2461 #endif /* IDETAPE_DEBUG_BUGS */
2463 tape->postponed_rq = NULL;
2465 /*
2466 * If the tape is still busy, postpone our request and service
2467 * the other device meanwhile.
2468 */
2469 status.all = HWIF(drive)->INB(IDE_STATUS_REG);
2471 if (!drive->dsc_overlap && !(rq->cmd[0] & REQ_IDETAPE_PC2))
2472 set_bit(IDETAPE_IGNORE_DSC, &tape->flags);
2474 if (drive->post_reset == 1) {
2475 set_bit(IDETAPE_IGNORE_DSC, &tape->flags);
2476 drive->post_reset = 0;
2479 if (tape->tape_still_time > 100 && tape->tape_still_time < 200)
2480 tape->measure_insert_time = 1;
2481 if (time_after(jiffies, tape->insert_time))
2482 tape->insert_speed = tape->insert_size / 1024 * HZ / (jiffies - tape->insert_time);
2483 calculate_speeds(drive);
2484 if (!test_and_clear_bit(IDETAPE_IGNORE_DSC, &tape->flags) &&
2485 !status.b.dsc) {
2486 if (postponed_rq == NULL) {
2487 tape->dsc_polling_start = jiffies;
2488 tape->dsc_polling_frequency = tape->best_dsc_rw_frequency;
2489 tape->dsc_timeout = jiffies + IDETAPE_DSC_RW_TIMEOUT;
2490 } else if (time_after(jiffies, tape->dsc_timeout)) {
2491 printk(KERN_ERR "ide-tape: %s: DSC timeout\n",
2492 tape->name);
2493 if (rq->cmd[0] & REQ_IDETAPE_PC2) {
2494 idetape_media_access_finished(drive);
2495 return ide_stopped;
2496 } else {
2497 return ide_do_reset(drive);
2499 } else if (time_after(jiffies, tape->dsc_polling_start + IDETAPE_DSC_MA_THRESHOLD))
2500 tape->dsc_polling_frequency = IDETAPE_DSC_MA_SLOW;
2501 idetape_postpone_request(drive);
2502 return ide_stopped;
2504 if (rq->cmd[0] & REQ_IDETAPE_READ) {
2505 tape->buffer_head++;
2506 #if USE_IOTRACE
2507 IO_trace(IO_IDETAPE_FIFO, tape->pipeline_head, tape->buffer_head, tape->tape_head, tape->minor);
2508 #endif
2509 tape->postpone_cnt = 0;
2510 pc = idetape_next_pc_storage(drive);
2511 idetape_create_read_cmd(tape, pc, rq->current_nr_sectors, (struct idetape_bh *)rq->special);
2512 goto out;
2514 if (rq->cmd[0] & REQ_IDETAPE_WRITE) {
2515 tape->buffer_head++;
2516 #if USE_IOTRACE
2517 IO_trace(IO_IDETAPE_FIFO, tape->pipeline_head, tape->buffer_head, tape->tape_head, tape->minor);
2518 #endif
2519 tape->postpone_cnt = 0;
2520 pc = idetape_next_pc_storage(drive);
2521 idetape_create_write_cmd(tape, pc, rq->current_nr_sectors, (struct idetape_bh *)rq->special);
2522 goto out;
2524 if (rq->cmd[0] & REQ_IDETAPE_READ_BUFFER) {
2525 tape->postpone_cnt = 0;
2526 pc = idetape_next_pc_storage(drive);
2527 idetape_create_read_buffer_cmd(tape, pc, rq->current_nr_sectors, (struct idetape_bh *)rq->special);
2528 goto out;
2530 if (rq->cmd[0] & REQ_IDETAPE_PC1) {
2531 pc = (idetape_pc_t *) rq->buffer;
2532 rq->cmd[0] &= ~(REQ_IDETAPE_PC1);
2533 rq->cmd[0] |= REQ_IDETAPE_PC2;
2534 goto out;
2536 if (rq->cmd[0] & REQ_IDETAPE_PC2) {
2537 idetape_media_access_finished(drive);
2538 return ide_stopped;
2540 BUG();
2541 out:
2542 return idetape_issue_packet_command(drive, pc);
2545 /*
2546 * Pipeline related functions
2547 */
2548 static inline int idetape_pipeline_active (idetape_tape_t *tape)
2550 int rc1, rc2;
2552 rc1 = test_bit(IDETAPE_PIPELINE_ACTIVE, &tape->flags);
2553 rc2 = (tape->active_data_request != NULL);
2554 return rc1;
2557 /*
2558 * idetape_kmalloc_stage uses __get_free_page to allocate a pipeline
2559 * stage, along with all the necessary small buffers which together make
2560 * a buffer of size tape->stage_size (or a bit more). We attempt to
2561 * combine sequential pages as much as possible.
2563 * Returns a pointer to the new allocated stage, or NULL if we
2564 * can't (or don't want to) allocate a stage.
2566 * Pipeline stages are optional and are used to increase performance.
2567 * If we can't allocate them, we'll manage without them.
2568 */
2569 static idetape_stage_t *__idetape_kmalloc_stage (idetape_tape_t *tape, int full, int clear)
2571 idetape_stage_t *stage;
2572 struct idetape_bh *prev_bh, *bh;
2573 int pages = tape->pages_per_stage;
2574 char *b_data = NULL;
2576 if ((stage = (idetape_stage_t *) kmalloc (sizeof (idetape_stage_t),GFP_KERNEL)) == NULL)
2577 return NULL;
2578 stage->next = NULL;
2580 bh = stage->bh = (struct idetape_bh *)kmalloc(sizeof(struct idetape_bh), GFP_KERNEL);
2581 if (bh == NULL)
2582 goto abort;
2583 bh->b_reqnext = NULL;
2584 if ((bh->b_data = (char *) __get_free_page (GFP_KERNEL)) == NULL)
2585 goto abort;
2586 if (clear)
2587 memset(bh->b_data, 0, PAGE_SIZE);
2588 bh->b_size = PAGE_SIZE;
2589 atomic_set(&bh->b_count, full ? bh->b_size : 0);
2591 while (--pages) {
2592 if ((b_data = (char *) __get_free_page (GFP_KERNEL)) == NULL)
2593 goto abort;
2594 if (clear)
2595 memset(b_data, 0, PAGE_SIZE);
2596 if (bh->b_data == b_data + PAGE_SIZE) {
2597 bh->b_size += PAGE_SIZE;
2598 bh->b_data -= PAGE_SIZE;
2599 if (full)
2600 atomic_add(PAGE_SIZE, &bh->b_count);
2601 continue;
2603 if (b_data == bh->b_data + bh->b_size) {
2604 bh->b_size += PAGE_SIZE;
2605 if (full)
2606 atomic_add(PAGE_SIZE, &bh->b_count);
2607 continue;
2609 prev_bh = bh;
2610 if ((bh = (struct idetape_bh *)kmalloc(sizeof(struct idetape_bh), GFP_KERNEL)) == NULL) {
2611 free_page((unsigned long) b_data);
2612 goto abort;
2614 bh->b_reqnext = NULL;
2615 bh->b_data = b_data;
2616 bh->b_size = PAGE_SIZE;
2617 atomic_set(&bh->b_count, full ? bh->b_size : 0);
2618 prev_bh->b_reqnext = bh;
2620 bh->b_size -= tape->excess_bh_size;
2621 if (full)
2622 atomic_sub(tape->excess_bh_size, &bh->b_count);
2623 return stage;
2624 abort:
2625 __idetape_kfree_stage(stage);
2626 return NULL;
2629 static idetape_stage_t *idetape_kmalloc_stage (idetape_tape_t *tape)
2631 idetape_stage_t *cache_stage = tape->cache_stage;
2633 #if IDETAPE_DEBUG_LOG
2634 if (tape->debug_level >= 4)
2635 printk(KERN_INFO "ide-tape: Reached idetape_kmalloc_stage\n");
2636 #endif /* IDETAPE_DEBUG_LOG */
2638 if (tape->nr_stages >= tape->max_stages)
2639 return NULL;
2640 if (cache_stage != NULL) {
2641 tape->cache_stage = NULL;
2642 return cache_stage;
2644 return __idetape_kmalloc_stage(tape, 0, 0);
2647 static int idetape_copy_stage_from_user (idetape_tape_t *tape, idetape_stage_t *stage, const char __user *buf, int n)
2649 struct idetape_bh *bh = tape->bh;
2650 int count;
2651 int ret = 0;
2653 while (n) {
2654 #if IDETAPE_DEBUG_BUGS
2655 if (bh == NULL) {
2656 printk(KERN_ERR "ide-tape: bh == NULL in "
2657 "idetape_copy_stage_from_user\n");
2658 return 1;
2660 #endif /* IDETAPE_DEBUG_BUGS */
2661 count = min((unsigned int)(bh->b_size - atomic_read(&bh->b_count)), (unsigned int)n);
2662 if (copy_from_user(bh->b_data + atomic_read(&bh->b_count), buf, count))
2663 ret = 1;
2664 n -= count;
2665 atomic_add(count, &bh->b_count);
2666 buf += count;
2667 if (atomic_read(&bh->b_count) == bh->b_size) {
2668 bh = bh->b_reqnext;
2669 if (bh)
2670 atomic_set(&bh->b_count, 0);
2673 tape->bh = bh;
2674 return ret;
2677 static int idetape_copy_stage_to_user (idetape_tape_t *tape, char __user *buf, idetape_stage_t *stage, int n)
2679 struct idetape_bh *bh = tape->bh;
2680 int count;
2681 int ret = 0;
2683 while (n) {
2684 #if IDETAPE_DEBUG_BUGS
2685 if (bh == NULL) {
2686 printk(KERN_ERR "ide-tape: bh == NULL in "
2687 "idetape_copy_stage_to_user\n");
2688 return 1;
2690 #endif /* IDETAPE_DEBUG_BUGS */
2691 count = min(tape->b_count, n);
2692 if (copy_to_user(buf, tape->b_data, count))
2693 ret = 1;
2694 n -= count;
2695 tape->b_data += count;
2696 tape->b_count -= count;
2697 buf += count;
2698 if (!tape->b_count) {
2699 tape->bh = bh = bh->b_reqnext;
2700 if (bh) {
2701 tape->b_data = bh->b_data;
2702 tape->b_count = atomic_read(&bh->b_count);
2706 return ret;
2709 static void idetape_init_merge_stage (idetape_tape_t *tape)
2711 struct idetape_bh *bh = tape->merge_stage->bh;
2713 tape->bh = bh;
2714 if (tape->chrdev_direction == idetape_direction_write)
2715 atomic_set(&bh->b_count, 0);
2716 else {
2717 tape->b_data = bh->b_data;
2718 tape->b_count = atomic_read(&bh->b_count);
2722 static void idetape_switch_buffers (idetape_tape_t *tape, idetape_stage_t *stage)
2724 struct idetape_bh *tmp;
2726 tmp = stage->bh;
2727 stage->bh = tape->merge_stage->bh;
2728 tape->merge_stage->bh = tmp;
2729 idetape_init_merge_stage(tape);
2732 /*
2733 * idetape_add_stage_tail adds a new stage at the end of the pipeline.
2734 */
2735 static void idetape_add_stage_tail (ide_drive_t *drive,idetape_stage_t *stage)
2737 idetape_tape_t *tape = drive->driver_data;
2738 unsigned long flags;
2740 #if IDETAPE_DEBUG_LOG
2741 if (tape->debug_level >= 4)
2742 printk (KERN_INFO "ide-tape: Reached idetape_add_stage_tail\n");
2743 #endif /* IDETAPE_DEBUG_LOG */
2744 spin_lock_irqsave(&tape->spinlock, flags);
2745 stage->next = NULL;
2746 if (tape->last_stage != NULL)
2747 tape->last_stage->next=stage;
2748 else
2749 tape->first_stage = tape->next_stage=stage;
2750 tape->last_stage = stage;
2751 if (tape->next_stage == NULL)
2752 tape->next_stage = tape->last_stage;
2753 tape->nr_stages++;
2754 tape->nr_pending_stages++;
2755 spin_unlock_irqrestore(&tape->spinlock, flags);
2758 /*
2759 * idetape_wait_for_request installs a completion in a pending request
2760 * and sleeps until it is serviced.
2762 * The caller should ensure that the request will not be serviced
2763 * before we install the completion (usually by disabling interrupts).
2764 */
2765 static void idetape_wait_for_request (ide_drive_t *drive, struct request *rq)
2767 DECLARE_COMPLETION(wait);
2768 idetape_tape_t *tape = drive->driver_data;
2770 #if IDETAPE_DEBUG_BUGS
2771 if (rq == NULL || (rq->flags & REQ_SPECIAL) == 0) {
2772 printk (KERN_ERR "ide-tape: bug: Trying to sleep on non-valid request\n");
2773 return;
2775 #endif /* IDETAPE_DEBUG_BUGS */
2776 rq->waiting = &wait;
2777 rq->end_io = blk_end_sync_rq;
2778 spin_unlock_irq(&tape->spinlock);
2779 wait_for_completion(&wait);
2780 /* The stage and its struct request have been deallocated */
2781 spin_lock_irq(&tape->spinlock);
2784 static ide_startstop_t idetape_read_position_callback (ide_drive_t *drive)
2786 idetape_tape_t *tape = drive->driver_data;
2787 idetape_read_position_result_t *result;
2789 #if IDETAPE_DEBUG_LOG
2790 if (tape->debug_level >= 4)
2791 printk(KERN_INFO "ide-tape: Reached idetape_read_position_callback\n");
2792 #endif /* IDETAPE_DEBUG_LOG */
2794 if (!tape->pc->error) {
2795 result = (idetape_read_position_result_t *) tape->pc->buffer;
2796 #if IDETAPE_DEBUG_LOG
2797 if (tape->debug_level >= 2)
2798 printk(KERN_INFO "ide-tape: BOP - %s\n",result->bop ? "Yes":"No");
2799 if (tape->debug_level >= 2)
2800 printk(KERN_INFO "ide-tape: EOP - %s\n",result->eop ? "Yes":"No");
2801 #endif /* IDETAPE_DEBUG_LOG */
2802 if (result->bpu) {
2803 printk(KERN_INFO "ide-tape: Block location is unknown to the tape\n");
2804 clear_bit(IDETAPE_ADDRESS_VALID, &tape->flags);
2805 idetape_end_request(drive, 0, 0);
2806 } else {
2807 #if IDETAPE_DEBUG_LOG
2808 if (tape->debug_level >= 2)
2809 printk(KERN_INFO "ide-tape: Block Location - %u\n", ntohl(result->first_block));
2810 #endif /* IDETAPE_DEBUG_LOG */
2811 tape->partition = result->partition;
2812 tape->first_frame_position = ntohl(result->first_block);
2813 tape->last_frame_position = ntohl(result->last_block);
2814 tape->blocks_in_buffer = result->blocks_in_buffer[2];
2815 set_bit(IDETAPE_ADDRESS_VALID, &tape->flags);
2816 idetape_end_request(drive, 1, 0);
2818 } else {
2819 idetape_end_request(drive, 0, 0);
2821 return ide_stopped;
2824 /*
2825 * idetape_create_write_filemark_cmd will:
2827 * 1. Write a filemark if write_filemark=1.
2828 * 2. Flush the device buffers without writing a filemark
2829 * if write_filemark=0.
2831 */
2832 static void idetape_create_write_filemark_cmd (ide_drive_t *drive, idetape_pc_t *pc,int write_filemark)
2834 idetape_init_pc(pc);
2835 pc->c[0] = IDETAPE_WRITE_FILEMARK_CMD;
2836 pc->c[4] = write_filemark;
2837 set_bit(PC_WAIT_FOR_DSC, &pc->flags);
2838 pc->callback = &idetape_pc_callback;
2841 static void idetape_create_test_unit_ready_cmd(idetape_pc_t *pc)
2843 idetape_init_pc(pc);
2844 pc->c[0] = IDETAPE_TEST_UNIT_READY_CMD;
2845 pc->callback = &idetape_pc_callback;
2848 /*
2849 * idetape_queue_pc_tail is based on the following functions:
2851 * ide_do_drive_cmd from ide.c
2852 * cdrom_queue_request and cdrom_queue_packet_command from ide-cd.c
2854 * We add a special packet command request to the tail of the request
2855 * queue, and wait for it to be serviced.
2857 * This is not to be called from within the request handling part
2858 * of the driver ! We allocate here data in the stack, and it is valid
2859 * until the request is finished. This is not the case for the bottom
2860 * part of the driver, where we are always leaving the functions to wait
2861 * for an interrupt or a timer event.
2863 * From the bottom part of the driver, we should allocate safe memory
2864 * using idetape_next_pc_storage and idetape_next_rq_storage, and add
2865 * the request to the request list without waiting for it to be serviced !
2866 * In that case, we usually use idetape_queue_pc_head.
2867 */
2868 static int __idetape_queue_pc_tail (ide_drive_t *drive, idetape_pc_t *pc)
2870 struct ide_tape_obj *tape = drive->driver_data;
2871 struct request rq;
2873 idetape_init_rq(&rq, REQ_IDETAPE_PC1);
2874 rq.buffer = (char *) pc;
2875 rq.rq_disk = tape->disk;
2876 return ide_do_drive_cmd(drive, &rq, ide_wait);
2879 static void idetape_create_load_unload_cmd (ide_drive_t *drive, idetape_pc_t *pc,int cmd)
2881 idetape_init_pc(pc);
2882 pc->c[0] = IDETAPE_LOAD_UNLOAD_CMD;
2883 pc->c[4] = cmd;
2884 set_bit(PC_WAIT_FOR_DSC, &pc->flags);
2885 pc->callback = &idetape_pc_callback;
2888 static int idetape_wait_ready(ide_drive_t *drive, unsigned long timeout)
2890 idetape_tape_t *tape = drive->driver_data;
2891 idetape_pc_t pc;
2892 int load_attempted = 0;
2894 /*
2895 * Wait for the tape to become ready
2896 */
2897 set_bit(IDETAPE_MEDIUM_PRESENT, &tape->flags);
2898 timeout += jiffies;
2899 while (time_before(jiffies, timeout)) {
2900 idetape_create_test_unit_ready_cmd(&pc);
2901 if (!__idetape_queue_pc_tail(drive, &pc))
2902 return 0;
2903 if ((tape->sense_key == 2 && tape->asc == 4 && tape->ascq == 2)
2904 || (tape->asc == 0x3A)) { /* no media */
2905 if (load_attempted)
2906 return -ENOMEDIUM;
2907 idetape_create_load_unload_cmd(drive, &pc, IDETAPE_LU_LOAD_MASK);
2908 __idetape_queue_pc_tail(drive, &pc);
2909 load_attempted = 1;
2910 /* not about to be ready */
2911 } else if (!(tape->sense_key == 2 && tape->asc == 4 &&
2912 (tape->ascq == 1 || tape->ascq == 8)))
2913 return -EIO;
2914 msleep(100);
2916 return -EIO;
2919 static int idetape_queue_pc_tail (ide_drive_t *drive,idetape_pc_t *pc)
2921 return __idetape_queue_pc_tail(drive, pc);
2924 static int idetape_flush_tape_buffers (ide_drive_t *drive)
2926 idetape_pc_t pc;
2927 int rc;
2929 idetape_create_write_filemark_cmd(drive, &pc, 0);
2930 if ((rc = idetape_queue_pc_tail(drive, &pc)))
2931 return rc;
2932 idetape_wait_ready(drive, 60 * 5 * HZ);
2933 return 0;
2936 static void idetape_create_read_position_cmd (idetape_pc_t *pc)
2938 idetape_init_pc(pc);
2939 pc->c[0] = IDETAPE_READ_POSITION_CMD;
2940 pc->request_transfer = 20;
2941 pc->callback = &idetape_read_position_callback;
2944 static int idetape_read_position (ide_drive_t *drive)
2946 idetape_tape_t *tape = drive->driver_data;
2947 idetape_pc_t pc;
2948 int position;
2950 #if IDETAPE_DEBUG_LOG
2951 if (tape->debug_level >= 4)
2952 printk(KERN_INFO "ide-tape: Reached idetape_read_position\n");
2953 #endif /* IDETAPE_DEBUG_LOG */
2955 idetape_create_read_position_cmd(&pc);
2956 if (idetape_queue_pc_tail(drive, &pc))
2957 return -1;
2958 position = tape->first_frame_position;
2959 return position;
2962 static void idetape_create_locate_cmd (ide_drive_t *drive, idetape_pc_t *pc, unsigned int block, u8 partition, int skip)
2964 idetape_init_pc(pc);
2965 pc->c[0] = IDETAPE_LOCATE_CMD;
2966 pc->c[1] = 2;
2967 put_unaligned(htonl(block), (unsigned int *) &pc->c[3]);
2968 pc->c[8] = partition;
2969 set_bit(PC_WAIT_FOR_DSC, &pc->flags);
2970 pc->callback = &idetape_pc_callback;
2973 static int idetape_create_prevent_cmd (ide_drive_t *drive, idetape_pc_t *pc, int prevent)
2975 idetape_tape_t *tape = drive->driver_data;
2977 if (!tape->capabilities.lock)
2978 return 0;
2980 idetape_init_pc(pc);
2981 pc->c[0] = IDETAPE_PREVENT_CMD;
2982 pc->c[4] = prevent;
2983 pc->callback = &idetape_pc_callback;
2984 return 1;
2987 static int __idetape_discard_read_pipeline (ide_drive_t *drive)
2989 idetape_tape_t *tape = drive->driver_data;
2990 unsigned long flags;
2991 int cnt;
2993 if (tape->chrdev_direction != idetape_direction_read)
2994 return 0;
2996 /* Remove merge stage. */
2997 cnt = tape->merge_stage_size / tape->tape_block_size;
2998 if (test_and_clear_bit(IDETAPE_FILEMARK, &tape->flags))
2999 ++cnt; /* Filemarks count as 1 sector */
3000 tape->merge_stage_size = 0;
3001 if (tape->merge_stage != NULL) {
3002 __idetape_kfree_stage(tape->merge_stage);
3003 tape->merge_stage = NULL;
3006 /* Clear pipeline flags. */
3007 clear_bit(IDETAPE_PIPELINE_ERROR, &tape->flags);
3008 tape->chrdev_direction = idetape_direction_none;
3010 /* Remove pipeline stages. */
3011 if (tape->first_stage == NULL)
3012 return 0;
3014 spin_lock_irqsave(&tape->spinlock, flags);
3015 tape->next_stage = NULL;
3016 if (idetape_pipeline_active(tape))
3017 idetape_wait_for_request(drive, tape->active_data_request);
3018 spin_unlock_irqrestore(&tape->spinlock, flags);
3020 while (tape->first_stage != NULL) {
3021 struct request *rq_ptr = &tape->first_stage->rq;
3023 cnt += rq_ptr->nr_sectors - rq_ptr->current_nr_sectors;
3024 if (rq_ptr->errors == IDETAPE_ERROR_FILEMARK)
3025 ++cnt;
3026 idetape_remove_stage_head(drive);
3028 tape->nr_pending_stages = 0;
3029 tape->max_stages = tape->min_pipeline;
3030 return cnt;
3033 /*
3034 * idetape_position_tape positions the tape to the requested block
3035 * using the LOCATE packet command. A READ POSITION command is then
3036 * issued to check where we are positioned.
3038 * Like all higher level operations, we queue the commands at the tail
3039 * of the request queue and wait for their completion.
3041 */
3042 static int idetape_position_tape (ide_drive_t *drive, unsigned int block, u8 partition, int skip)
3044 idetape_tape_t *tape = drive->driver_data;
3045 int retval;
3046 idetape_pc_t pc;
3048 if (tape->chrdev_direction == idetape_direction_read)
3049 __idetape_discard_read_pipeline(drive);
3050 idetape_wait_ready(drive, 60 * 5 * HZ);
3051 idetape_create_locate_cmd(drive, &pc, block, partition, skip);
3052 retval = idetape_queue_pc_tail(drive, &pc);
3053 if (retval)
3054 return (retval);
3056 idetape_create_read_position_cmd(&pc);
3057 return (idetape_queue_pc_tail(drive, &pc));
3060 static void idetape_discard_read_pipeline (ide_drive_t *drive, int restore_position)
3062 idetape_tape_t *tape = drive->driver_data;
3063 int cnt;
3064 int seek, position;
3066 cnt = __idetape_discard_read_pipeline(drive);
3067 if (restore_position) {
3068 position = idetape_read_position(drive);
3069 seek = position > cnt ? position - cnt : 0;
3070 if (idetape_position_tape(drive, seek, 0, 0)) {
3071 printk(KERN_INFO "ide-tape: %s: position_tape failed in discard_pipeline()\n", tape->name);
3072 return;
3077 /*
3078 * idetape_queue_rw_tail generates a read/write request for the block
3079 * device interface and wait for it to be serviced.
3080 */
3081 static int idetape_queue_rw_tail(ide_drive_t *drive, int cmd, int blocks, struct idetape_bh *bh)
3083 idetape_tape_t *tape = drive->driver_data;
3084 struct request rq;
3086 #if IDETAPE_DEBUG_LOG
3087 if (tape->debug_level >= 2)
3088 printk(KERN_INFO "ide-tape: idetape_queue_rw_tail: cmd=%d\n",cmd);
3089 #endif /* IDETAPE_DEBUG_LOG */
3090 #if IDETAPE_DEBUG_BUGS
3091 if (idetape_pipeline_active(tape)) {
3092 printk(KERN_ERR "ide-tape: bug: the pipeline is active in idetape_queue_rw_tail\n");
3093 return (0);
3095 #endif /* IDETAPE_DEBUG_BUGS */
3097 idetape_init_rq(&rq, cmd);
3098 rq.rq_disk = tape->disk;
3099 rq.special = (void *)bh;
3100 rq.sector = tape->first_frame_position;
3101 rq.nr_sectors = rq.current_nr_sectors = blocks;
3102 (void) ide_do_drive_cmd(drive, &rq, ide_wait);
3104 if ((cmd & (REQ_IDETAPE_READ | REQ_IDETAPE_WRITE)) == 0)
3105 return 0;
3107 if (tape->merge_stage)
3108 idetape_init_merge_stage(tape);
3109 if (rq.errors == IDETAPE_ERROR_GENERAL)
3110 return -EIO;
3111 return (tape->tape_block_size * (blocks-rq.current_nr_sectors));
3114 /*
3115 * idetape_insert_pipeline_into_queue is used to start servicing the
3116 * pipeline stages, starting from tape->next_stage.
3117 */
3118 static void idetape_insert_pipeline_into_queue (ide_drive_t *drive)
3120 idetape_tape_t *tape = drive->driver_data;
3122 if (tape->next_stage == NULL)
3123 return;
3124 if (!idetape_pipeline_active(tape)) {
3125 set_bit(IDETAPE_PIPELINE_ACTIVE, &tape->flags);
3126 idetape_active_next_stage(drive);
3127 (void) ide_do_drive_cmd(drive, tape->active_data_request, ide_end);
3131 static void idetape_create_inquiry_cmd (idetape_pc_t *pc)
3133 idetape_init_pc(pc);
3134 pc->c[0] = IDETAPE_INQUIRY_CMD;
3135 pc->c[4] = pc->request_transfer = 254;
3136 pc->callback = &idetape_pc_callback;
3139 static void idetape_create_rewind_cmd (ide_drive_t *drive, idetape_pc_t *pc)
3141 idetape_init_pc(pc);
3142 pc->c[0] = IDETAPE_REWIND_CMD;
3143 set_bit(PC_WAIT_FOR_DSC, &pc->flags);
3144 pc->callback = &idetape_pc_callback;
3147 #if 0
3148 static void idetape_create_mode_select_cmd (idetape_pc_t *pc, int length)
3150 idetape_init_pc(pc);
3151 set_bit(PC_WRITING, &pc->flags);
3152 pc->c[0] = IDETAPE_MODE_SELECT_CMD;
3153 pc->c[1] = 0x10;
3154 put_unaligned(htons(length), (unsigned short *) &pc->c[3]);
3155 pc->request_transfer = 255;
3156 pc->callback = &idetape_pc_callback;
3158 #endif
3160 static void idetape_create_erase_cmd (idetape_pc_t *pc)
3162 idetape_init_pc(pc);
3163 pc->c[0] = IDETAPE_ERASE_CMD;
3164 pc->c[1] = 1;
3165 set_bit(PC_WAIT_FOR_DSC, &pc->flags);
3166 pc->callback = &idetape_pc_callback;
3169 static void idetape_create_space_cmd (idetape_pc_t *pc,int count, u8 cmd)
3171 idetape_init_pc(pc);
3172 pc->c[0] = IDETAPE_SPACE_CMD;
3173 put_unaligned(htonl(count), (unsigned int *) &pc->c[1]);
3174 pc->c[1] = cmd;
3175 set_bit(PC_WAIT_FOR_DSC, &pc->flags);
3176 pc->callback = &idetape_pc_callback;
3179 static void idetape_wait_first_stage (ide_drive_t *drive)
3181 idetape_tape_t *tape = drive->driver_data;
3182 unsigned long flags;
3184 if (tape->first_stage == NULL)
3185 return;
3186 spin_lock_irqsave(&tape->spinlock, flags);
3187 if (tape->active_stage == tape->first_stage)
3188 idetape_wait_for_request(drive, tape->active_data_request);
3189 spin_unlock_irqrestore(&tape->spinlock, flags);
3192 /*
3193 * idetape_add_chrdev_write_request tries to add a character device
3194 * originated write request to our pipeline. In case we don't succeed,
3195 * we revert to non-pipelined operation mode for this request.
3197 * 1. Try to allocate a new pipeline stage.
3198 * 2. If we can't, wait for more and more requests to be serviced
3199 * and try again each time.
3200 * 3. If we still can't allocate a stage, fallback to
3201 * non-pipelined operation mode for this request.
3202 */
3203 static int idetape_add_chrdev_write_request (ide_drive_t *drive, int blocks)
3205 idetape_tape_t *tape = drive->driver_data;
3206 idetape_stage_t *new_stage;
3207 unsigned long flags;
3208 struct request *rq;
3210 #if IDETAPE_DEBUG_LOG
3211 if (tape->debug_level >= 3)
3212 printk(KERN_INFO "ide-tape: Reached idetape_add_chrdev_write_request\n");
3213 #endif /* IDETAPE_DEBUG_LOG */
3215 /*
3216 * Attempt to allocate a new stage.
3217 * Pay special attention to possible race conditions.
3218 */
3219 while ((new_stage = idetape_kmalloc_stage(tape)) == NULL) {
3220 spin_lock_irqsave(&tape->spinlock, flags);
3221 if (idetape_pipeline_active(tape)) {
3222 idetape_wait_for_request(drive, tape->active_data_request);
3223 spin_unlock_irqrestore(&tape->spinlock, flags);
3224 } else {
3225 spin_unlock_irqrestore(&tape->spinlock, flags);
3226 idetape_insert_pipeline_into_queue(drive);
3227 if (idetape_pipeline_active(tape))
3228 continue;
3229 /*
3230 * Linux is short on memory. Fallback to
3231 * non-pipelined operation mode for this request.
3232 */
3233 return idetape_queue_rw_tail(drive, REQ_IDETAPE_WRITE, blocks, tape->merge_stage->bh);
3236 rq = &new_stage->rq;
3237 idetape_init_rq(rq, REQ_IDETAPE_WRITE);
3238 /* Doesn't actually matter - We always assume sequential access */
3239 rq->sector = tape->first_frame_position;
3240 rq->nr_sectors = rq->current_nr_sectors = blocks;
3242 idetape_switch_buffers(tape, new_stage);
3243 idetape_add_stage_tail(drive, new_stage);
3244 tape->pipeline_head++;
3245 #if USE_IOTRACE
3246 IO_trace(IO_IDETAPE_FIFO, tape->pipeline_head, tape->buffer_head, tape->tape_head, tape->minor);
3247 #endif
3248 calculate_speeds(drive);
3250 /*
3251 * Estimate whether the tape has stopped writing by checking
3252 * if our write pipeline is currently empty. If we are not
3253 * writing anymore, wait for the pipeline to be full enough
3254 * (90%) before starting to service requests, so that we will
3255 * be able to keep up with the higher speeds of the tape.
3256 */
3257 if (!idetape_pipeline_active(tape)) {
3258 if (tape->nr_stages >= tape->max_stages * 9 / 10 ||
3259 tape->nr_stages >= tape->max_stages - tape->uncontrolled_pipeline_head_speed * 3 * 1024 / tape->tape_block_size) {
3260 tape->measure_insert_time = 1;
3261 tape->insert_time = jiffies;
3262 tape->insert_size = 0;
3263 tape->insert_speed = 0;
3264 idetape_insert_pipeline_into_queue(drive);
3267 if (test_and_clear_bit(IDETAPE_PIPELINE_ERROR, &tape->flags))
3268 /* Return a deferred error */
3269 return -EIO;
3270 return blocks;
3273 /*
3274 * idetape_wait_for_pipeline will wait until all pending pipeline
3275 * requests are serviced. Typically called on device close.
3276 */
3277 static void idetape_wait_for_pipeline (ide_drive_t *drive)
3279 idetape_tape_t *tape = drive->driver_data;
3280 unsigned long flags;
3282 while (tape->next_stage || idetape_pipeline_active(tape)) {
3283 idetape_insert_pipeline_into_queue(drive);
3284 spin_lock_irqsave(&tape->spinlock, flags);
3285 if (idetape_pipeline_active(tape))
3286 idetape_wait_for_request(drive, tape->active_data_request);
3287 spin_unlock_irqrestore(&tape->spinlock, flags);
3291 static void idetape_empty_write_pipeline (ide_drive_t *drive)
3293 idetape_tape_t *tape = drive->driver_data;
3294 int blocks, min;
3295 struct idetape_bh *bh;
3297 #if IDETAPE_DEBUG_BUGS
3298 if (tape->chrdev_direction != idetape_direction_write) {
3299 printk(KERN_ERR "ide-tape: bug: Trying to empty write pipeline, but we are not writing.\n");
3300 return;
3302 if (tape->merge_stage_size > tape->stage_size) {
3303 printk(KERN_ERR "ide-tape: bug: merge_buffer too big\n");
3304 tape->merge_stage_size = tape->stage_size;
3306 #endif /* IDETAPE_DEBUG_BUGS */
3307 if (tape->merge_stage_size) {
3308 blocks = tape->merge_stage_size / tape->tape_block_size;
3309 if (tape->merge_stage_size % tape->tape_block_size) {
3310 unsigned int i;
3312 blocks++;
3313 i = tape->tape_block_size - tape->merge_stage_size % tape->tape_block_size;
3314 bh = tape->bh->b_reqnext;
3315 while (bh) {
3316 atomic_set(&bh->b_count, 0);
3317 bh = bh->b_reqnext;
3319 bh = tape->bh;
3320 while (i) {
3321 if (bh == NULL) {
3323 printk(KERN_INFO "ide-tape: bug, bh NULL\n");
3324 break;
3326 min = min(i, (unsigned int)(bh->b_size - atomic_read(&bh->b_count)));
3327 memset(bh->b_data + atomic_read(&bh->b_count), 0, min);
3328 atomic_add(min, &bh->b_count);
3329 i -= min;
3330 bh = bh->b_reqnext;
3333 (void) idetape_add_chrdev_write_request(drive, blocks);
3334 tape->merge_stage_size = 0;
3336 idetape_wait_for_pipeline(drive);
3337 if (tape->merge_stage != NULL) {
3338 __idetape_kfree_stage(tape->merge_stage);
3339 tape->merge_stage = NULL;
3341 clear_bit(IDETAPE_PIPELINE_ERROR, &tape->flags);
3342 tape->chrdev_direction = idetape_direction_none;
3344 /*
3345 * On the next backup, perform the feedback loop again.
3346 * (I don't want to keep sense information between backups,
3347 * as some systems are constantly on, and the system load
3348 * can be totally different on the next backup).
3349 */
3350 tape->max_stages = tape->min_pipeline;
3351 #if IDETAPE_DEBUG_BUGS
3352 if (tape->first_stage != NULL ||
3353 tape->next_stage != NULL ||
3354 tape->last_stage != NULL ||
3355 tape->nr_stages != 0) {
3356 printk(KERN_ERR "ide-tape: ide-tape pipeline bug, "
3357 "first_stage %p, next_stage %p, "
3358 "last_stage %p, nr_stages %d\n",
3359 tape->first_stage, tape->next_stage,
3360 tape->last_stage, tape->nr_stages);
3362 #endif /* IDETAPE_DEBUG_BUGS */
3365 static void idetape_restart_speed_control (ide_drive_t *drive)
3367 idetape_tape_t *tape = drive->driver_data;
3369 tape->restart_speed_control_req = 0;
3370 tape->pipeline_head = 0;
3371 tape->controlled_last_pipeline_head = tape->uncontrolled_last_pipeline_head = 0;
3372 tape->controlled_previous_pipeline_head = tape->uncontrolled_previous_pipeline_head = 0;
3373 tape->pipeline_head_speed = tape->controlled_pipeline_head_speed = 5000;
3374 tape->uncontrolled_pipeline_head_speed = 0;
3375 tape->controlled_pipeline_head_time = tape->uncontrolled_pipeline_head_time = jiffies;
3376 tape->controlled_previous_head_time = tape->uncontrolled_previous_head_time = jiffies;
3379 static int idetape_initiate_read (ide_drive_t *drive, int max_stages)
3381 idetape_tape_t *tape = drive->driver_data;
3382 idetape_stage_t *new_stage;
3383 struct request rq;
3384 int bytes_read;
3385 int blocks = tape->capabilities.ctl;
3387 /* Initialize read operation */
3388 if (tape->chrdev_direction != idetape_direction_read) {
3389 if (tape->chrdev_direction == idetape_direction_write) {
3390 idetape_empty_write_pipeline(drive);
3391 idetape_flush_tape_buffers(drive);
3393 #if IDETAPE_DEBUG_BUGS
3394 if (tape->merge_stage || tape->merge_stage_size) {
3395 printk (KERN_ERR "ide-tape: merge_stage_size should be 0 now\n");
3396 tape->merge_stage_size = 0;
3398 #endif /* IDETAPE_DEBUG_BUGS */
3399 if ((tape->merge_stage = __idetape_kmalloc_stage(tape, 0, 0)) == NULL)
3400 return -ENOMEM;
3401 tape->chrdev_direction = idetape_direction_read;
3403 /*
3404 * Issue a read 0 command to ensure that DSC handshake
3405 * is switched from completion mode to buffer available
3406 * mode.
3407 * No point in issuing this if DSC overlap isn't supported,
3408 * some drives (Seagate STT3401A) will return an error.
3409 */
3410 if (drive->dsc_overlap) {
3411 bytes_read = idetape_queue_rw_tail(drive, REQ_IDETAPE_READ, 0, tape->merge_stage->bh);
3412 if (bytes_read < 0) {
3413 __idetape_kfree_stage(tape->merge_stage);
3414 tape->merge_stage = NULL;
3415 tape->chrdev_direction = idetape_direction_none;
3416 return bytes_read;
3420 if (tape->restart_speed_control_req)
3421 idetape_restart_speed_control(drive);
3422 idetape_init_rq(&rq, REQ_IDETAPE_READ);
3423 rq.sector = tape->first_frame_position;
3424 rq.nr_sectors = rq.current_nr_sectors = blocks;
3425 if (!test_bit(IDETAPE_PIPELINE_ERROR, &tape->flags) &&
3426 tape->nr_stages < max_stages) {
3427 new_stage = idetape_kmalloc_stage(tape);
3428 while (new_stage != NULL) {
3429 new_stage->rq = rq;
3430 idetape_add_stage_tail(drive, new_stage);
3431 if (tape->nr_stages >= max_stages)
3432 break;
3433 new_stage = idetape_kmalloc_stage(tape);
3436 if (!idetape_pipeline_active(tape)) {
3437 if (tape->nr_pending_stages >= 3 * max_stages / 4) {
3438 tape->measure_insert_time = 1;
3439 tape->insert_time = jiffies;
3440 tape->insert_size = 0;
3441 tape->insert_speed = 0;
3442 idetape_insert_pipeline_into_queue(drive);
3445 return 0;
3448 /*
3449 * idetape_add_chrdev_read_request is called from idetape_chrdev_read
3450 * to service a character device read request and add read-ahead
3451 * requests to our pipeline.
3452 */
3453 static int idetape_add_chrdev_read_request (ide_drive_t *drive,int blocks)
3455 idetape_tape_t *tape = drive->driver_data;
3456 unsigned long flags;
3457 struct request *rq_ptr;
3458 int bytes_read;
3460 #if IDETAPE_DEBUG_LOG
3461 if (tape->debug_level >= 4)
3462 printk(KERN_INFO "ide-tape: Reached idetape_add_chrdev_read_request, %d blocks\n", blocks);
3463 #endif /* IDETAPE_DEBUG_LOG */
3465 /*
3466 * If we are at a filemark, return a read length of 0
3467 */
3468 if (test_bit(IDETAPE_FILEMARK, &tape->flags))
3469 return 0;
3471 /*
3472 * Wait for the next block to be available at the head
3473 * of the pipeline
3474 */
3475 idetape_initiate_read(drive, tape->max_stages);
3476 if (tape->first_stage == NULL) {
3477 if (test_bit(IDETAPE_PIPELINE_ERROR, &tape->flags))
3478 return 0;
3479 return idetape_queue_rw_tail(drive, REQ_IDETAPE_READ, blocks, tape->merge_stage->bh);
3481 idetape_wait_first_stage(drive);
3482 rq_ptr = &tape->first_stage->rq;
3483 bytes_read = tape->tape_block_size * (rq_ptr->nr_sectors - rq_ptr->current_nr_sectors);
3484 rq_ptr->nr_sectors = rq_ptr->current_nr_sectors = 0;
3487 if (rq_ptr->errors == IDETAPE_ERROR_EOD)
3488 return 0;
3489 else {
3490 idetape_switch_buffers(tape, tape->first_stage);
3491 if (rq_ptr->errors == IDETAPE_ERROR_FILEMARK)
3492 set_bit(IDETAPE_FILEMARK, &tape->flags);
3493 spin_lock_irqsave(&tape->spinlock, flags);
3494 idetape_remove_stage_head(drive);
3495 spin_unlock_irqrestore(&tape->spinlock, flags);
3496 tape->pipeline_head++;
3497 #if USE_IOTRACE
3498 IO_trace(IO_IDETAPE_FIFO, tape->pipeline_head, tape->buffer_head, tape->tape_head, tape->minor);
3499 #endif
3500 calculate_speeds(drive);
3502 #if IDETAPE_DEBUG_BUGS
3503 if (bytes_read > blocks * tape->tape_block_size) {
3504 printk(KERN_ERR "ide-tape: bug: trying to return more bytes than requested\n");
3505 bytes_read = blocks * tape->tape_block_size;
3507 #endif /* IDETAPE_DEBUG_BUGS */
3508 return (bytes_read);
3511 static void idetape_pad_zeros (ide_drive_t *drive, int bcount)
3513 idetape_tape_t *tape = drive->driver_data;
3514 struct idetape_bh *bh;
3515 int blocks;
3517 while (bcount) {
3518 unsigned int count;
3520 bh = tape->merge_stage->bh;
3521 count = min(tape->stage_size, bcount);
3522 bcount -= count;
3523 blocks = count / tape->tape_block_size;
3524 while (count) {
3525 atomic_set(&bh->b_count, min(count, (unsigned int)bh->b_size));
3526 memset(bh->b_data, 0, atomic_read(&bh->b_count));
3527 count -= atomic_read(&bh->b_count);
3528 bh = bh->b_reqnext;
3530 idetape_queue_rw_tail(drive, REQ_IDETAPE_WRITE, blocks, tape->merge_stage->bh);
3534 static int idetape_pipeline_size (ide_drive_t *drive)
3536 idetape_tape_t *tape = drive->driver_data;
3537 idetape_stage_t *stage;
3538 struct request *rq;
3539 int size = 0;
3541 idetape_wait_for_pipeline(drive);
3542 stage = tape->first_stage;
3543 while (stage != NULL) {
3544 rq = &stage->rq;
3545 size += tape->tape_block_size * (rq->nr_sectors-rq->current_nr_sectors);
3546 if (rq->errors == IDETAPE_ERROR_FILEMARK)
3547 size += tape->tape_block_size;
3548 stage = stage->next;
3550 size += tape->merge_stage_size;
3551 return size;
3554 /*
3555 * Rewinds the tape to the Beginning Of the current Partition (BOP).
3557 * We currently support only one partition.
3558 */
3559 static int idetape_rewind_tape (ide_drive_t *drive)
3561 int retval;
3562 idetape_pc_t pc;
3563 #if IDETAPE_DEBUG_LOG
3564 idetape_tape_t *tape = drive->driver_data;
3565 if (tape->debug_level >= 2)
3566 printk(KERN_INFO "ide-tape: Reached idetape_rewind_tape\n");
3567 #endif /* IDETAPE_DEBUG_LOG */
3569 idetape_create_rewind_cmd(drive, &pc);
3570 retval = idetape_queue_pc_tail(drive, &pc);
3571 if (retval)
3572 return retval;
3574 idetape_create_read_position_cmd(&pc);
3575 retval = idetape_queue_pc_tail(drive, &pc);
3576 if (retval)
3577 return retval;
3578 return 0;
3581 /*
3582 * Our special ide-tape ioctl's.
3584 * Currently there aren't any ioctl's.
3585 * mtio.h compatible commands should be issued to the character device
3586 * interface.
3587 */
3588 static int idetape_blkdev_ioctl(ide_drive_t *drive, unsigned int cmd, unsigned long arg)
3590 idetape_tape_t *tape = drive->driver_data;
3591 idetape_config_t config;
3592 void __user *argp = (void __user *)arg;
3594 #if IDETAPE_DEBUG_LOG
3595 if (tape->debug_level >= 4)
3596 printk(KERN_INFO "ide-tape: Reached idetape_blkdev_ioctl\n");
3597 #endif /* IDETAPE_DEBUG_LOG */
3598 switch (cmd) {
3599 case 0x0340:
3600 if (copy_from_user(&config, argp, sizeof (idetape_config_t)))
3601 return -EFAULT;
3602 tape->best_dsc_rw_frequency = config.dsc_rw_frequency;
3603 tape->max_stages = config.nr_stages;
3604 break;
3605 case 0x0350:
3606 config.dsc_rw_frequency = (int) tape->best_dsc_rw_frequency;
3607 config.nr_stages = tape->max_stages;
3608 if (copy_to_user(argp, &config, sizeof (idetape_config_t)))
3609 return -EFAULT;
3610 break;
3611 default:
3612 return -EIO;
3614 return 0;
3617 /*
3618 * idetape_space_over_filemarks is now a bit more complicated than just
3619 * passing the command to the tape since we may have crossed some
3620 * filemarks during our pipelined read-ahead mode.
3622 * As a minor side effect, the pipeline enables us to support MTFSFM when
3623 * the filemark is in our internal pipeline even if the tape doesn't
3624 * support spacing over filemarks in the reverse direction.
3625 */
3626 static int idetape_space_over_filemarks (ide_drive_t *drive,short mt_op,int mt_count)
3628 idetape_tape_t *tape = drive->driver_data;
3629 idetape_pc_t pc;
3630 unsigned long flags;
3631 int retval,count=0;
3633 if (mt_count == 0)
3634 return 0;
3635 if (MTBSF == mt_op || MTBSFM == mt_op) {
3636 if (!tape->capabilities.sprev)
3637 return -EIO;
3638 mt_count = - mt_count;
3641 if (tape->chrdev_direction == idetape_direction_read) {
3642 /*
3643 * We have a read-ahead buffer. Scan it for crossed
3644 * filemarks.
3645 */
3646 tape->merge_stage_size = 0;
3647 if (test_and_clear_bit(IDETAPE_FILEMARK, &tape->flags))
3648 ++count;
3649 while (tape->first_stage != NULL) {
3650 if (count == mt_count) {
3651 if (mt_op == MTFSFM)
3652 set_bit(IDETAPE_FILEMARK, &tape->flags);
3653 return 0;
3655 spin_lock_irqsave(&tape->spinlock, flags);
3656 if (tape->first_stage == tape->active_stage) {
3657 /*
3658 * We have reached the active stage in the read pipeline.
3659 * There is no point in allowing the drive to continue
3660 * reading any farther, so we stop the pipeline.
3662 * This section should be moved to a separate subroutine,
3663 * because a similar function is performed in
3664 * __idetape_discard_read_pipeline(), for example.
3665 */
3666 tape->next_stage = NULL;
3667 spin_unlock_irqrestore(&tape->spinlock, flags);
3668 idetape_wait_first_stage(drive);
3669 tape->next_stage = tape->first_stage->next;
3670 } else
3671 spin_unlock_irqrestore(&tape->spinlock, flags);
3672 if (tape->first_stage->rq.errors == IDETAPE_ERROR_FILEMARK)
3673 ++count;
3674 idetape_remove_stage_head(drive);
3676 idetape_discard_read_pipeline(drive, 0);
3679 /*
3680 * The filemark was not found in our internal pipeline.
3681 * Now we can issue the space command.
3682 */
3683 switch (mt_op) {
3684 case MTFSF:
3685 case MTBSF:
3686 idetape_create_space_cmd(&pc,mt_count-count,IDETAPE_SPACE_OVER_FILEMARK);
3687 return (idetape_queue_pc_tail(drive, &pc));
3688 case MTFSFM:
3689 case MTBSFM:
3690 if (!tape->capabilities.sprev)
3691 return (-EIO);
3692 retval = idetape_space_over_filemarks(drive, MTFSF, mt_count-count);
3693 if (retval) return (retval);
3694 count = (MTBSFM == mt_op ? 1 : -1);
3695 return (idetape_space_over_filemarks(drive, MTFSF, count));
3696 default:
3697 printk(KERN_ERR "ide-tape: MTIO operation %d not supported\n",mt_op);
3698 return (-EIO);
3703 /*
3704 * Our character device read / write functions.
3706 * The tape is optimized to maximize throughput when it is transferring
3707 * an integral number of the "continuous transfer limit", which is
3708 * a parameter of the specific tape (26 KB on my particular tape).
3709 * (32 kB for Onstream)
3711 * As of version 1.3 of the driver, the character device provides an
3712 * abstract continuous view of the media - any mix of block sizes (even 1
3713 * byte) on the same backup/restore procedure is supported. The driver
3714 * will internally convert the requests to the recommended transfer unit,
3715 * so that an unmatch between the user's block size to the recommended
3716 * size will only result in a (slightly) increased driver overhead, but
3717 * will no longer hit performance.
3718 * This is not applicable to Onstream.
3719 */
3720 static ssize_t idetape_chrdev_read (struct file *file, char __user *buf,
3721 size_t count, loff_t *ppos)
3723 struct ide_tape_obj *tape = ide_tape_f(file);
3724 ide_drive_t *drive = tape->drive;
3725 ssize_t bytes_read,temp, actually_read = 0, rc;
3726 ssize_t ret = 0;
3728 #if IDETAPE_DEBUG_LOG
3729 if (tape->debug_level >= 3)
3730 printk(KERN_INFO "ide-tape: Reached idetape_chrdev_read, count %Zd\n", count);
3731 #endif /* IDETAPE_DEBUG_LOG */
3733 if (tape->chrdev_direction != idetape_direction_read) {
3734 if (test_bit(IDETAPE_DETECT_BS, &tape->flags))
3735 if (count > tape->tape_block_size &&
3736 (count % tape->tape_block_size) == 0)
3737 tape->user_bs_factor = count / tape->tape_block_size;
3739 if ((rc = idetape_initiate_read(drive, tape->max_stages)) < 0)
3740 return rc;
3741 if (count == 0)
3742 return (0);
3743 if (tape->merge_stage_size) {
3744 actually_read = min((unsigned int)(tape->merge_stage_size), (unsigned int)count);
3745 if (idetape_copy_stage_to_user(tape, buf, tape->merge_stage, actually_read))
3746 ret = -EFAULT;
3747 buf += actually_read;
3748 tape->merge_stage_size -= actually_read;
3749 count -= actually_read;
3751 while (count >= tape->stage_size) {
3752 bytes_read = idetape_add_chrdev_read_request(drive, tape->capabilities.ctl);
3753 if (bytes_read <= 0)
3754 goto finish;
3755 if (idetape_copy_stage_to_user(tape, buf, tape->merge_stage, bytes_read))
3756 ret = -EFAULT;
3757 buf += bytes_read;
3758 count -= bytes_read;
3759 actually_read += bytes_read;
3761 if (count) {
3762 bytes_read = idetape_add_chrdev_read_request(drive, tape->capabilities.ctl);
3763 if (bytes_read <= 0)
3764 goto finish;
3765 temp = min((unsigned long)count, (unsigned long)bytes_read);
3766 if (idetape_copy_stage_to_user(tape, buf, tape->merge_stage, temp))
3767 ret = -EFAULT;
3768 actually_read += temp;
3769 tape->merge_stage_size = bytes_read-temp;
3771 finish:
3772 if (!actually_read && test_bit(IDETAPE_FILEMARK, &tape->flags)) {
3773 #if IDETAPE_DEBUG_LOG
3774 if (tape->debug_level >= 2)
3775 printk(KERN_INFO "ide-tape: %s: spacing over filemark\n", tape->name);
3776 #endif
3777 idetape_space_over_filemarks(drive, MTFSF, 1);
3778 return 0;
3781 return (ret) ? ret : actually_read;
3784 static ssize_t idetape_chrdev_write (struct file *file, const char __user *buf,
3785 size_t count, loff_t *ppos)
3787 struct ide_tape_obj *tape = ide_tape_f(file);
3788 ide_drive_t *drive = tape->drive;
3789 ssize_t actually_written = 0;
3790 ssize_t ret = 0;
3792 /* The drive is write protected. */
3793 if (tape->write_prot)
3794 return -EACCES;
3796 #if IDETAPE_DEBUG_LOG
3797 if (tape->debug_level >= 3)
3798 printk(KERN_INFO "ide-tape: Reached idetape_chrdev_write, "
3799 "count %Zd\n", count);
3800 #endif /* IDETAPE_DEBUG_LOG */
3802 /* Initialize write operation */
3803 if (tape->chrdev_direction != idetape_direction_write) {
3804 if (tape->chrdev_direction == idetape_direction_read)
3805 idetape_discard_read_pipeline(drive, 1);
3806 #if IDETAPE_DEBUG_BUGS
3807 if (tape->merge_stage || tape->merge_stage_size) {
3808 printk(KERN_ERR "ide-tape: merge_stage_size "
3809 "should be 0 now\n");
3810 tape->merge_stage_size = 0;
3812 #endif /* IDETAPE_DEBUG_BUGS */
3813 if ((tape->merge_stage = __idetape_kmalloc_stage(tape, 0, 0)) == NULL)
3814 return -ENOMEM;
3815 tape->chrdev_direction = idetape_direction_write;
3816 idetape_init_merge_stage(tape);
3818 /*
3819 * Issue a write 0 command to ensure that DSC handshake
3820 * is switched from completion mode to buffer available
3821 * mode.
3822 * No point in issuing this if DSC overlap isn't supported,
3823 * some drives (Seagate STT3401A) will return an error.
3824 */
3825 if (drive->dsc_overlap) {
3826 ssize_t retval = idetape_queue_rw_tail(drive, REQ_IDETAPE_WRITE, 0, tape->merge_stage->bh);
3827 if (retval < 0) {
3828 __idetape_kfree_stage(tape->merge_stage);
3829 tape->merge_stage = NULL;
3830 tape->chrdev_direction = idetape_direction_none;
3831 return retval;
3835 if (count == 0)
3836 return (0);
3837 if (tape->restart_speed_control_req)
3838 idetape_restart_speed_control(drive);
3839 if (tape->merge_stage_size) {
3840 #if IDETAPE_DEBUG_BUGS
3841 if (tape->merge_stage_size >= tape->stage_size) {
3842 printk(KERN_ERR "ide-tape: bug: merge buffer too big\n");
3843 tape->merge_stage_size = 0;
3845 #endif /* IDETAPE_DEBUG_BUGS */
3846 actually_written = min((unsigned int)(tape->stage_size - tape->merge_stage_size), (unsigned int)count);
3847 if (idetape_copy_stage_from_user(tape, tape->merge_stage, buf, actually_written))
3848 ret = -EFAULT;
3849 buf += actually_written;
3850 tape->merge_stage_size += actually_written;
3851 count -= actually_written;
3853 if (tape->merge_stage_size == tape->stage_size) {
3854 ssize_t retval;
3855 tape->merge_stage_size = 0;
3856 retval = idetape_add_chrdev_write_request(drive, tape->capabilities.ctl);
3857 if (retval <= 0)
3858 return (retval);
3861 while (count >= tape->stage_size) {
3862 ssize_t retval;
3863 if (idetape_copy_stage_from_user(tape, tape->merge_stage, buf, tape->stage_size))
3864 ret = -EFAULT;
3865 buf += tape->stage_size;
3866 count -= tape->stage_size;
3867 retval = idetape_add_chrdev_write_request(drive, tape->capabilities.ctl);
3868 actually_written += tape->stage_size;
3869 if (retval <= 0)
3870 return (retval);
3872 if (count) {
3873 actually_written += count;
3874 if (idetape_copy_stage_from_user(tape, tape->merge_stage, buf, count))
3875 ret = -EFAULT;
3876 tape->merge_stage_size += count;
3878 return (ret) ? ret : actually_written;
3881 static int idetape_write_filemark (ide_drive_t *drive)
3883 idetape_pc_t pc;
3885 /* Write a filemark */
3886 idetape_create_write_filemark_cmd(drive, &pc, 1);
3887 if (idetape_queue_pc_tail(drive, &pc)) {
3888 printk(KERN_ERR "ide-tape: Couldn't write a filemark\n");
3889 return -EIO;
3891 return 0;
3894 /*
3895 * idetape_mtioctop is called from idetape_chrdev_ioctl when
3896 * the general mtio MTIOCTOP ioctl is requested.
3898 * We currently support the following mtio.h operations:
3900 * MTFSF - Space over mt_count filemarks in the positive direction.
3901 * The tape is positioned after the last spaced filemark.
3903 * MTFSFM - Same as MTFSF, but the tape is positioned before the
3904 * last filemark.
3906 * MTBSF - Steps background over mt_count filemarks, tape is
3907 * positioned before the last filemark.
3909 * MTBSFM - Like MTBSF, only tape is positioned after the last filemark.
3911 * Note:
3913 * MTBSF and MTBSFM are not supported when the tape doesn't
3914 * support spacing over filemarks in the reverse direction.
3915 * In this case, MTFSFM is also usually not supported (it is
3916 * supported in the rare case in which we crossed the filemark
3917 * during our read-ahead pipelined operation mode).
3919 * MTWEOF - Writes mt_count filemarks. Tape is positioned after
3920 * the last written filemark.
3922 * MTREW - Rewinds tape.
3924 * MTLOAD - Loads the tape.
3926 * MTOFFL - Puts the tape drive "Offline": Rewinds the tape and
3927 * MTUNLOAD prevents further access until the media is replaced.
3929 * MTNOP - Flushes tape buffers.
3931 * MTRETEN - Retension media. This typically consists of one end
3932 * to end pass on the media.
3934 * MTEOM - Moves to the end of recorded data.
3936 * MTERASE - Erases tape.
3938 * MTSETBLK - Sets the user block size to mt_count bytes. If
3939 * mt_count is 0, we will attempt to autodetect
3940 * the block size.
3942 * MTSEEK - Positions the tape in a specific block number, where
3943 * each block is assumed to contain which user_block_size
3944 * bytes.
3946 * MTSETPART - Switches to another tape partition.
3948 * MTLOCK - Locks the tape door.
3950 * MTUNLOCK - Unlocks the tape door.
3952 * The following commands are currently not supported:
3954 * MTFSS, MTBSS, MTWSM, MTSETDENSITY,
3955 * MTSETDRVBUFFER, MT_ST_BOOLEANS, MT_ST_WRITE_THRESHOLD.
3956 */
3957 static int idetape_mtioctop (ide_drive_t *drive,short mt_op,int mt_count)
3959 idetape_tape_t *tape = drive->driver_data;
3960 idetape_pc_t pc;
3961 int i,retval;
3963 #if IDETAPE_DEBUG_LOG
3964 if (tape->debug_level >= 1)
3965 printk(KERN_INFO "ide-tape: Handling MTIOCTOP ioctl: "
3966 "mt_op=%d, mt_count=%d\n", mt_op, mt_count);
3967 #endif /* IDETAPE_DEBUG_LOG */
3968 /*
3969 * Commands which need our pipelined read-ahead stages.
3970 */
3971 switch (mt_op) {
3972 case MTFSF:
3973 case MTFSFM:
3974 case MTBSF:
3975 case MTBSFM:
3976 if (!mt_count)
3977 return (0);
3978 return (idetape_space_over_filemarks(drive,mt_op,mt_count));
3979 default:
3980 break;
3982 switch (mt_op) {
3983 case MTWEOF:
3984 if (tape->write_prot)
3985 return -EACCES;
3986 idetape_discard_read_pipeline(drive, 1);
3987 for (i = 0; i < mt_count; i++) {
3988 retval = idetape_write_filemark(drive);
3989 if (retval)
3990 return retval;
3992 return (0);
3993 case MTREW:
3994 idetape_discard_read_pipeline(drive, 0);
3995 if (idetape_rewind_tape(drive))
3996 return -EIO;
3997 return 0;
3998 case MTLOAD:
3999 idetape_discard_read_pipeline(drive, 0);
4000 idetape_create_load_unload_cmd(drive, &pc, IDETAPE_LU_LOAD_MASK);
4001 return (idetape_queue_pc_tail(drive, &pc));
4002 case MTUNLOAD:
4003 case MTOFFL:
4004 /*
4005 * If door is locked, attempt to unlock before
4006 * attempting to eject.
4007 */
4008 if (tape->door_locked) {
4009 if (idetape_create_prevent_cmd(drive, &pc, 0))
4010 if (!idetape_queue_pc_tail(drive, &pc))
4011 tape->door_locked = DOOR_UNLOCKED;
4013 idetape_discard_read_pipeline(drive, 0);
4014 idetape_create_load_unload_cmd(drive, &pc,!IDETAPE_LU_LOAD_MASK);
4015 retval = idetape_queue_pc_tail(drive, &pc);
4016 if (!retval)
4017 clear_bit(IDETAPE_MEDIUM_PRESENT, &tape->flags);
4018 return retval;
4019 case MTNOP:
4020 idetape_discard_read_pipeline(drive, 0);
4021 return (idetape_flush_tape_buffers(drive));
4022 case MTRETEN:
4023 idetape_discard_read_pipeline(drive, 0);
4024 idetape_create_load_unload_cmd(drive, &pc,IDETAPE_LU_RETENSION_MASK | IDETAPE_LU_LOAD_MASK);
4025 return (idetape_queue_pc_tail(drive, &pc));
4026 case MTEOM:
4027 idetape_create_space_cmd(&pc, 0, IDETAPE_SPACE_TO_EOD);
4028 return (idetape_queue_pc_tail(drive, &pc));
4029 case MTERASE:
4030 (void) idetape_rewind_tape(drive);
4031 idetape_create_erase_cmd(&pc);
4032 return (idetape_queue_pc_tail(drive, &pc));
4033 case MTSETBLK:
4034 if (mt_count) {
4035 if (mt_count < tape->tape_block_size || mt_count % tape->tape_block_size)
4036 return -EIO;
4037 tape->user_bs_factor = mt_count / tape->tape_block_size;
4038 clear_bit(IDETAPE_DETECT_BS, &tape->flags);
4039 } else
4040 set_bit(IDETAPE_DETECT_BS, &tape->flags);
4041 return 0;
4042 case MTSEEK:
4043 idetape_discard_read_pipeline(drive, 0);
4044 return idetape_position_tape(drive, mt_count * tape->user_bs_factor, tape->partition, 0);
4045 case MTSETPART:
4046 idetape_discard_read_pipeline(drive, 0);
4047 return (idetape_position_tape(drive, 0, mt_count, 0));
4048 case MTFSR:
4049 case MTBSR:
4050 case MTLOCK:
4051 if (!idetape_create_prevent_cmd(drive, &pc, 1))
4052 return 0;
4053 retval = idetape_queue_pc_tail(drive, &pc);
4054 if (retval) return retval;
4055 tape->door_locked = DOOR_EXPLICITLY_LOCKED;
4056 return 0;
4057 case MTUNLOCK:
4058 if (!idetape_create_prevent_cmd(drive, &pc, 0))
4059 return 0;
4060 retval = idetape_queue_pc_tail(drive, &pc);
4061 if (retval) return retval;
4062 tape->door_locked = DOOR_UNLOCKED;
4063 return 0;
4064 default:
4065 printk(KERN_ERR "ide-tape: MTIO operation %d not "
4066 "supported\n", mt_op);
4067 return (-EIO);
4071 /*
4072 * Our character device ioctls.
4074 * General mtio.h magnetic io commands are supported here, and not in
4075 * the corresponding block interface.
4077 * The following ioctls are supported:
4079 * MTIOCTOP - Refer to idetape_mtioctop for detailed description.
4081 * MTIOCGET - The mt_dsreg field in the returned mtget structure
4082 * will be set to (user block size in bytes <<
4083 * MT_ST_BLKSIZE_SHIFT) & MT_ST_BLKSIZE_MASK.
4085 * The mt_blkno is set to the current user block number.
4086 * The other mtget fields are not supported.
4088 * MTIOCPOS - The current tape "block position" is returned. We
4089 * assume that each block contains user_block_size
4090 * bytes.
4092 * Our own ide-tape ioctls are supported on both interfaces.
4093 */
4094 static int idetape_chrdev_ioctl (struct inode *inode, struct file *file, unsigned int cmd, unsigned long arg)
4096 struct ide_tape_obj *tape = ide_tape_f(file);
4097 ide_drive_t *drive = tape->drive;
4098 struct mtop mtop;
4099 struct mtget mtget;
4100 struct mtpos mtpos;
4101 int block_offset = 0, position = tape->first_frame_position;
4102 void __user *argp = (void __user *)arg;
4104 #if IDETAPE_DEBUG_LOG
4105 if (tape->debug_level >= 3)
4106 printk(KERN_INFO "ide-tape: Reached idetape_chrdev_ioctl, "
4107 "cmd=%u\n", cmd);
4108 #endif /* IDETAPE_DEBUG_LOG */
4110 tape->restart_speed_control_req = 1;
4111 if (tape->chrdev_direction == idetape_direction_write) {
4112 idetape_empty_write_pipeline(drive);
4113 idetape_flush_tape_buffers(drive);
4115 if (cmd == MTIOCGET || cmd == MTIOCPOS) {
4116 block_offset = idetape_pipeline_size(drive) / (tape->tape_block_size * tape->user_bs_factor);
4117 if ((position = idetape_read_position(drive)) < 0)
4118 return -EIO;
4120 switch (cmd) {
4121 case MTIOCTOP:
4122 if (copy_from_user(&mtop, argp, sizeof (struct mtop)))
4123 return -EFAULT;
4124 return (idetape_mtioctop(drive,mtop.mt_op,mtop.mt_count));
4125 case MTIOCGET:
4126 memset(&mtget, 0, sizeof (struct mtget));
4127 mtget.mt_type = MT_ISSCSI2;
4128 mtget.mt_blkno = position / tape->user_bs_factor - block_offset;
4129 mtget.mt_dsreg = ((tape->tape_block_size * tape->user_bs_factor) << MT_ST_BLKSIZE_SHIFT) & MT_ST_BLKSIZE_MASK;
4130 if (tape->drv_write_prot) {
4131 mtget.mt_gstat |= GMT_WR_PROT(0xffffffff);
4133 if (copy_to_user(argp, &mtget, sizeof(struct mtget)))
4134 return -EFAULT;
4135 return 0;
4136 case MTIOCPOS:
4137 mtpos.mt_blkno = position / tape->user_bs_factor - block_offset;
4138 if (copy_to_user(argp, &mtpos, sizeof(struct mtpos)))
4139 return -EFAULT;
4140 return 0;
4141 default:
4142 if (tape->chrdev_direction == idetape_direction_read)
4143 idetape_discard_read_pipeline(drive, 1);
4144 return idetape_blkdev_ioctl(drive, cmd, arg);
4148 static void idetape_get_blocksize_from_block_descriptor(ide_drive_t *drive);
4150 /*
4151 * Our character device open function.
4152 */
4153 static int idetape_chrdev_open (struct inode *inode, struct file *filp)
4155 unsigned int minor = iminor(inode), i = minor & ~0xc0;
4156 ide_drive_t *drive;
4157 idetape_tape_t *tape;
4158 idetape_pc_t pc;
4159 int retval;
4161 /*
4162 * We really want to do nonseekable_open(inode, filp); here, but some
4163 * versions of tar incorrectly call lseek on tapes and bail out if that
4164 * fails. So we disallow pread() and pwrite(), but permit lseeks.
4165 */
4166 filp->f_mode &= ~(FMODE_PREAD | FMODE_PWRITE);
4168 #if IDETAPE_DEBUG_LOG
4169 printk(KERN_INFO "ide-tape: Reached idetape_chrdev_open\n");
4170 #endif /* IDETAPE_DEBUG_LOG */
4172 if (i >= MAX_HWIFS * MAX_DRIVES)
4173 return -ENXIO;
4175 if (!(tape = ide_tape_chrdev_get(i)))
4176 return -ENXIO;
4178 drive = tape->drive;
4180 filp->private_data = tape;
4182 if (test_and_set_bit(IDETAPE_BUSY, &tape->flags)) {
4183 retval = -EBUSY;
4184 goto out_put_tape;
4187 retval = idetape_wait_ready(drive, 60 * HZ);
4188 if (retval) {
4189 clear_bit(IDETAPE_BUSY, &tape->flags);
4190 printk(KERN_ERR "ide-tape: %s: drive not ready\n", tape->name);
4191 goto out_put_tape;
4194 idetape_read_position(drive);
4195 if (!test_bit(IDETAPE_ADDRESS_VALID, &tape->flags))
4196 (void)idetape_rewind_tape(drive);
4198 if (tape->chrdev_direction != idetape_direction_read)
4199 clear_bit(IDETAPE_PIPELINE_ERROR, &tape->flags);
4201 /* Read block size and write protect status from drive. */
4202 idetape_get_blocksize_from_block_descriptor(drive);
4204 /* Set write protect flag if device is opened as read-only. */
4205 if ((filp->f_flags & O_ACCMODE) == O_RDONLY)
4206 tape->write_prot = 1;
4207 else
4208 tape->write_prot = tape->drv_write_prot;
4210 /* Make sure drive isn't write protected if user wants to write. */
4211 if (tape->write_prot) {
4212 if ((filp->f_flags & O_ACCMODE) == O_WRONLY ||
4213 (filp->f_flags & O_ACCMODE) == O_RDWR) {
4214 clear_bit(IDETAPE_BUSY, &tape->flags);
4215 retval = -EROFS;
4216 goto out_put_tape;
4220 /*
4221 * Lock the tape drive door so user can't eject.
4222 */
4223 if (tape->chrdev_direction == idetape_direction_none) {
4224 if (idetape_create_prevent_cmd(drive, &pc, 1)) {
4225 if (!idetape_queue_pc_tail(drive, &pc)) {
4226 if (tape->door_locked != DOOR_EXPLICITLY_LOCKED)
4227 tape->door_locked = DOOR_LOCKED;
4231 idetape_restart_speed_control(drive);
4232 tape->restart_speed_control_req = 0;
4233 return 0;
4235 out_put_tape:
4236 ide_tape_put(tape);
4237 return retval;
4240 static void idetape_write_release (ide_drive_t *drive, unsigned int minor)
4242 idetape_tape_t *tape = drive->driver_data;
4244 idetape_empty_write_pipeline(drive);
4245 tape->merge_stage = __idetape_kmalloc_stage(tape, 1, 0);
4246 if (tape->merge_stage != NULL) {
4247 idetape_pad_zeros(drive, tape->tape_block_size * (tape->user_bs_factor - 1));
4248 __idetape_kfree_stage(tape->merge_stage);
4249 tape->merge_stage = NULL;
4251 idetape_write_filemark(drive);
4252 idetape_flush_tape_buffers(drive);
4253 idetape_flush_tape_buffers(drive);
4256 /*
4257 * Our character device release function.
4258 */
4259 static int idetape_chrdev_release (struct inode *inode, struct file *filp)
4261 struct ide_tape_obj *tape = ide_tape_f(filp);
4262 ide_drive_t *drive = tape->drive;
4263 idetape_pc_t pc;
4264 unsigned int minor = iminor(inode);
4266 lock_kernel();
4267 tape = drive->driver_data;
4268 #if IDETAPE_DEBUG_LOG
4269 if (tape->debug_level >= 3)
4270 printk(KERN_INFO "ide-tape: Reached idetape_chrdev_release\n");
4271 #endif /* IDETAPE_DEBUG_LOG */
4273 if (tape->chrdev_direction == idetape_direction_write)
4274 idetape_write_release(drive, minor);
4275 if (tape->chrdev_direction == idetape_direction_read) {
4276 if (minor < 128)
4277 idetape_discard_read_pipeline(drive, 1);
4278 else
4279 idetape_wait_for_pipeline(drive);
4281 if (tape->cache_stage != NULL) {
4282 __idetape_kfree_stage(tape->cache_stage);
4283 tape->cache_stage = NULL;
4285 if (minor < 128 && test_bit(IDETAPE_MEDIUM_PRESENT, &tape->flags))
4286 (void) idetape_rewind_tape(drive);
4287 if (tape->chrdev_direction == idetape_direction_none) {
4288 if (tape->door_locked == DOOR_LOCKED) {
4289 if (idetape_create_prevent_cmd(drive, &pc, 0)) {
4290 if (!idetape_queue_pc_tail(drive, &pc))
4291 tape->door_locked = DOOR_UNLOCKED;
4295 clear_bit(IDETAPE_BUSY, &tape->flags);
4296 ide_tape_put(tape);
4297 unlock_kernel();
4298 return 0;
4301 /*
4302 * idetape_identify_device is called to check the contents of the
4303 * ATAPI IDENTIFY command results. We return:
4305 * 1 If the tape can be supported by us, based on the information
4306 * we have so far.
4308 * 0 If this tape driver is not currently supported by us.
4309 */
4310 static int idetape_identify_device (ide_drive_t *drive)
4312 struct idetape_id_gcw gcw;
4313 struct hd_driveid *id = drive->id;
4314 #if IDETAPE_DEBUG_INFO
4315 unsigned short mask,i;
4316 #endif /* IDETAPE_DEBUG_INFO */
4318 if (drive->id_read == 0)
4319 return 1;
4321 *((unsigned short *) &gcw) = id->config;
4323 #if IDETAPE_DEBUG_INFO
4324 printk(KERN_INFO "ide-tape: Dumping ATAPI Identify Device tape parameters\n");
4325 printk(KERN_INFO "ide-tape: Protocol Type: ");
4326 switch (gcw.protocol) {
4327 case 0: case 1: printk("ATA\n");break;
4328 case 2: printk("ATAPI\n");break;
4329 case 3: printk("Reserved (Unknown to ide-tape)\n");break;
4331 printk(KERN_INFO "ide-tape: Device Type: %x - ",gcw.device_type);
4332 switch (gcw.device_type) {
4333 case 0: printk("Direct-access Device\n");break;
4334 case 1: printk("Streaming Tape Device\n");break;
4335 case 2: case 3: case 4: printk("Reserved\n");break;
4336 case 5: printk("CD-ROM Device\n");break;
4337 case 6: printk("Reserved\n");
4338 case 7: printk("Optical memory Device\n");break;
4339 case 0x1f: printk("Unknown or no Device type\n");break;
4340 default: printk("Reserved\n");
4342 printk(KERN_INFO "ide-tape: Removable: %s",gcw.removable ? "Yes\n":"No\n");
4343 printk(KERN_INFO "ide-tape: Command Packet DRQ Type: ");
4344 switch (gcw.drq_type) {
4345 case 0: printk("Microprocessor DRQ\n");break;
4346 case 1: printk("Interrupt DRQ\n");break;
4347 case 2: printk("Accelerated DRQ\n");break;
4348 case 3: printk("Reserved\n");break;
4350 printk(KERN_INFO "ide-tape: Command Packet Size: ");
4351 switch (gcw.packet_size) {
4352 case 0: printk("12 bytes\n");break;
4353 case 1: printk("16 bytes\n");break;
4354 default: printk("Reserved\n");break;
4356 printk(KERN_INFO "ide-tape: Model: %.40s\n",id->model);
4357 printk(KERN_INFO "ide-tape: Firmware Revision: %.8s\n",id->fw_rev);
4358 printk(KERN_INFO "ide-tape: Serial Number: %.20s\n",id->serial_no);
4359 printk(KERN_INFO "ide-tape: Write buffer size: %d bytes\n",id->buf_size*512);
4360 printk(KERN_INFO "ide-tape: DMA: %s",id->capability & 0x01 ? "Yes\n":"No\n");
4361 printk(KERN_INFO "ide-tape: LBA: %s",id->capability & 0x02 ? "Yes\n":"No\n");
4362 printk(KERN_INFO "ide-tape: IORDY can be disabled: %s",id->capability & 0x04 ? "Yes\n":"No\n");
4363 printk(KERN_INFO "ide-tape: IORDY supported: %s",id->capability & 0x08 ? "Yes\n":"Unknown\n");
4364 printk(KERN_INFO "ide-tape: ATAPI overlap supported: %s",id->capability & 0x20 ? "Yes\n":"No\n");
4365 printk(KERN_INFO "ide-tape: PIO Cycle Timing Category: %d\n",id->tPIO);
4366 printk(KERN_INFO "ide-tape: DMA Cycle Timing Category: %d\n",id->tDMA);
4367 printk(KERN_INFO "ide-tape: Single Word DMA supported modes: ");
4368 for (i=0,mask=1;i<8;i++,mask=mask << 1) {
4369 if (id->dma_1word & mask)
4370 printk("%d ",i);
4371 if (id->dma_1word & (mask << 8))
4372 printk("(active) ");
4374 printk("\n");
4375 printk(KERN_INFO "ide-tape: Multi Word DMA supported modes: ");
4376 for (i=0,mask=1;i<8;i++,mask=mask << 1) {
4377 if (id->dma_mword & mask)
4378 printk("%d ",i);
4379 if (id->dma_mword & (mask << 8))
4380 printk("(active) ");
4382 printk("\n");
4383 if (id->field_valid & 0x0002) {
4384 printk(KERN_INFO "ide-tape: Enhanced PIO Modes: %s\n",
4385 id->eide_pio_modes & 1 ? "Mode 3":"None");
4386 printk(KERN_INFO "ide-tape: Minimum Multi-word DMA cycle per word: ");
4387 if (id->eide_dma_min == 0)
4388 printk("Not supported\n");
4389 else
4390 printk("%d ns\n",id->eide_dma_min);
4392 printk(KERN_INFO "ide-tape: Manufacturer\'s Recommended Multi-word cycle: ");
4393 if (id->eide_dma_time == 0)
4394 printk("Not supported\n");
4395 else
4396 printk("%d ns\n",id->eide_dma_time);
4398 printk(KERN_INFO "ide-tape: Minimum PIO cycle without IORDY: ");
4399 if (id->eide_pio == 0)
4400 printk("Not supported\n");
4401 else
4402 printk("%d ns\n",id->eide_pio);
4404 printk(KERN_INFO "ide-tape: Minimum PIO cycle with IORDY: ");
4405 if (id->eide_pio_iordy == 0)
4406 printk("Not supported\n");
4407 else
4408 printk("%d ns\n",id->eide_pio_iordy);
4410 } else
4411 printk(KERN_INFO "ide-tape: According to the device, fields 64-70 are not valid.\n");
4412 #endif /* IDETAPE_DEBUG_INFO */
4414 /* Check that we can support this device */
4416 if (gcw.protocol !=2 )
4417 printk(KERN_ERR "ide-tape: Protocol is not ATAPI\n");
4418 else if (gcw.device_type != 1)
4419 printk(KERN_ERR "ide-tape: Device type is not set to tape\n");
4420 else if (!gcw.removable)
4421 printk(KERN_ERR "ide-tape: The removable flag is not set\n");
4422 else if (gcw.packet_size != 0) {
4423 printk(KERN_ERR "ide-tape: Packet size is not 12 bytes long\n");
4424 if (gcw.packet_size == 1)
4425 printk(KERN_ERR "ide-tape: Sorry, padding to 16 bytes is still not supported\n");
4426 } else
4427 return 1;
4428 return 0;
4431 /*
4432 * Use INQUIRY to get the firmware revision
4433 */
4434 static void idetape_get_inquiry_results (ide_drive_t *drive)
4436 char *r;
4437 idetape_tape_t *tape = drive->driver_data;
4438 idetape_pc_t pc;
4439 idetape_inquiry_result_t *inquiry;
4441 idetape_create_inquiry_cmd(&pc);
4442 if (idetape_queue_pc_tail(drive, &pc)) {
4443 printk(KERN_ERR "ide-tape: %s: can't get INQUIRY results\n", tape->name);
4444 return;
4446 inquiry = (idetape_inquiry_result_t *) pc.buffer;
4447 memcpy(tape->vendor_id, inquiry->vendor_id, 8);
4448 memcpy(tape->product_id, inquiry->product_id, 16);
4449 memcpy(tape->firmware_revision, inquiry->revision_level, 4);
4450 ide_fixstring(tape->vendor_id, 10, 0);
4451 ide_fixstring(tape->product_id, 18, 0);
4452 ide_fixstring(tape->firmware_revision, 6, 0);
4453 r = tape->firmware_revision;
4454 if (*(r + 1) == '.')
4455 tape->firmware_revision_num = (*r - '0') * 100 + (*(r + 2) - '0') * 10 + *(r + 3) - '0';
4456 printk(KERN_INFO "ide-tape: %s <-> %s: %s %s rev %s\n", drive->name, tape->name, tape->vendor_id, tape->product_id, tape->firmware_revision);
4459 /*
4460 * idetape_get_mode_sense_results asks the tape about its various
4461 * parameters. In particular, we will adjust our data transfer buffer
4462 * size to the recommended value as returned by the tape.
4463 */
4464 static void idetape_get_mode_sense_results (ide_drive_t *drive)
4466 idetape_tape_t *tape = drive->driver_data;
4467 idetape_pc_t pc;
4468 idetape_mode_parameter_header_t *header;
4469 idetape_capabilities_page_t *capabilities;
4471 idetape_create_mode_sense_cmd(&pc, IDETAPE_CAPABILITIES_PAGE);
4472 if (idetape_queue_pc_tail(drive, &pc)) {
4473 printk(KERN_ERR "ide-tape: Can't get tape parameters - assuming some default values\n");
4474 tape->tape_block_size = 512;
4475 tape->capabilities.ctl = 52;
4476 tape->capabilities.speed = 450;
4477 tape->capabilities.buffer_size = 6 * 52;
4478 return;
4480 header = (idetape_mode_parameter_header_t *) pc.buffer;
4481 capabilities = (idetape_capabilities_page_t *) (pc.buffer + sizeof(idetape_mode_parameter_header_t) + header->bdl);
4483 capabilities->max_speed = ntohs(capabilities->max_speed);
4484 capabilities->ctl = ntohs(capabilities->ctl);
4485 capabilities->speed = ntohs(capabilities->speed);
4486 capabilities->buffer_size = ntohs(capabilities->buffer_size);
4488 if (!capabilities->speed) {
4489 printk(KERN_INFO "ide-tape: %s: overriding capabilities->speed (assuming 650KB/sec)\n", drive->name);
4490 capabilities->speed = 650;
4492 if (!capabilities->max_speed) {
4493 printk(KERN_INFO "ide-tape: %s: overriding capabilities->max_speed (assuming 650KB/sec)\n", drive->name);
4494 capabilities->max_speed = 650;
4497 tape->capabilities = *capabilities; /* Save us a copy */
4498 if (capabilities->blk512)
4499 tape->tape_block_size = 512;
4500 else if (capabilities->blk1024)
4501 tape->tape_block_size = 1024;
4503 #if IDETAPE_DEBUG_INFO
4504 printk(KERN_INFO "ide-tape: Dumping the results of the MODE SENSE packet command\n");
4505 printk(KERN_INFO "ide-tape: Mode Parameter Header:\n");
4506 printk(KERN_INFO "ide-tape: Mode Data Length - %d\n",header->mode_data_length);
4507 printk(KERN_INFO "ide-tape: Medium Type - %d\n",header->medium_type);
4508 printk(KERN_INFO "ide-tape: Device Specific Parameter - %d\n",header->dsp);
4509 printk(KERN_INFO "ide-tape: Block Descriptor Length - %d\n",header->bdl);
4511 printk(KERN_INFO "ide-tape: Capabilities and Mechanical Status Page:\n");
4512 printk(KERN_INFO "ide-tape: Page code - %d\n",capabilities->page_code);
4513 printk(KERN_INFO "ide-tape: Page length - %d\n",capabilities->page_length);
4514 printk(KERN_INFO "ide-tape: Read only - %s\n",capabilities->ro ? "Yes":"No");
4515 printk(KERN_INFO "ide-tape: Supports reverse space - %s\n",capabilities->sprev ? "Yes":"No");
4516 printk(KERN_INFO "ide-tape: Supports erase initiated formatting - %s\n",capabilities->efmt ? "Yes":"No");
4517 printk(KERN_INFO "ide-tape: Supports QFA two Partition format - %s\n",capabilities->qfa ? "Yes":"No");
4518 printk(KERN_INFO "ide-tape: Supports locking the medium - %s\n",capabilities->lock ? "Yes":"No");
4519 printk(KERN_INFO "ide-tape: The volume is currently locked - %s\n",capabilities->locked ? "Yes":"No");
4520 printk(KERN_INFO "ide-tape: The device defaults in the prevent state - %s\n",capabilities->prevent ? "Yes":"No");
4521 printk(KERN_INFO "ide-tape: Supports ejecting the medium - %s\n",capabilities->eject ? "Yes":"No");
4522 printk(KERN_INFO "ide-tape: Supports error correction - %s\n",capabilities->ecc ? "Yes":"No");
4523 printk(KERN_INFO "ide-tape: Supports data compression - %s\n",capabilities->cmprs ? "Yes":"No");
4524 printk(KERN_INFO "ide-tape: Supports 512 bytes block size - %s\n",capabilities->blk512 ? "Yes":"No");
4525 printk(KERN_INFO "ide-tape: Supports 1024 bytes block size - %s\n",capabilities->blk1024 ? "Yes":"No");
4526 printk(KERN_INFO "ide-tape: Supports 32768 bytes block size / Restricted byte count for PIO transfers - %s\n",capabilities->blk32768 ? "Yes":"No");
4527 printk(KERN_INFO "ide-tape: Maximum supported speed in KBps - %d\n",capabilities->max_speed);
4528 printk(KERN_INFO "ide-tape: Continuous transfer limits in blocks - %d\n",capabilities->ctl);
4529 printk(KERN_INFO "ide-tape: Current speed in KBps - %d\n",capabilities->speed);
4530 printk(KERN_INFO "ide-tape: Buffer size - %d\n",capabilities->buffer_size*512);
4531 #endif /* IDETAPE_DEBUG_INFO */
4534 /*
4535 * ide_get_blocksize_from_block_descriptor does a mode sense page 0 with block descriptor
4536 * and if it succeeds sets the tape block size with the reported value
4537 */
4538 static void idetape_get_blocksize_from_block_descriptor(ide_drive_t *drive)
4541 idetape_tape_t *tape = drive->driver_data;
4542 idetape_pc_t pc;
4543 idetape_mode_parameter_header_t *header;
4544 idetape_parameter_block_descriptor_t *block_descrp;
4546 idetape_create_mode_sense_cmd(&pc, IDETAPE_BLOCK_DESCRIPTOR);
4547 if (idetape_queue_pc_tail(drive, &pc)) {
4548 printk(KERN_ERR "ide-tape: Can't get block descriptor\n");
4549 if (tape->tape_block_size == 0) {
4550 printk(KERN_WARNING "ide-tape: Cannot deal with zero block size, assume 32k\n");
4551 tape->tape_block_size = 32768;
4553 return;
4555 header = (idetape_mode_parameter_header_t *) pc.buffer;
4556 block_descrp = (idetape_parameter_block_descriptor_t *) (pc.buffer + sizeof(idetape_mode_parameter_header_t));
4557 tape->tape_block_size =( block_descrp->length[0]<<16) + (block_descrp->length[1]<<8) + block_descrp->length[2];
4558 tape->drv_write_prot = (header->dsp & 0x80) >> 7;
4560 #if IDETAPE_DEBUG_INFO
4561 printk(KERN_INFO "ide-tape: Adjusted block size - %d\n", tape->tape_block_size);
4562 #endif /* IDETAPE_DEBUG_INFO */
4564 static void idetape_add_settings (ide_drive_t *drive)
4566 idetape_tape_t *tape = drive->driver_data;
4568 /*
4569 * drive setting name read/write ioctl ioctl data type min max mul_factor div_factor data pointer set function
4570 */
4571 ide_add_setting(drive, "buffer", SETTING_READ, -1, -1, TYPE_SHORT, 0, 0xffff, 1, 2, &tape->capabilities.buffer_size, NULL);
4572 ide_add_setting(drive, "pipeline_min", SETTING_RW, -1, -1, TYPE_INT, 1, 0xffff, tape->stage_size / 1024, 1, &tape->min_pipeline, NULL);
4573 ide_add_setting(drive, "pipeline", SETTING_RW, -1, -1, TYPE_INT, 1, 0xffff, tape->stage_size / 1024, 1, &tape->max_stages, NULL);
4574 ide_add_setting(drive, "pipeline_max", SETTING_RW, -1, -1, TYPE_INT, 1, 0xffff, tape->stage_size / 1024, 1, &tape->max_pipeline, NULL);
4575 ide_add_setting(drive, "pipeline_used",SETTING_READ, -1, -1, TYPE_INT, 0, 0xffff, tape->stage_size / 1024, 1, &tape->nr_stages, NULL);
4576 ide_add_setting(drive, "pipeline_pending",SETTING_READ,-1, -1, TYPE_INT, 0, 0xffff, tape->stage_size / 1024, 1, &tape->nr_pending_stages, NULL);
4577 ide_add_setting(drive, "speed", SETTING_READ, -1, -1, TYPE_SHORT, 0, 0xffff, 1, 1, &tape->capabilities.speed, NULL);
4578 ide_add_setting(drive, "stage", SETTING_READ, -1, -1, TYPE_INT, 0, 0xffff, 1, 1024, &tape->stage_size, NULL);
4579 ide_add_setting(drive, "tdsc", SETTING_RW, -1, -1, TYPE_INT, IDETAPE_DSC_RW_MIN, IDETAPE_DSC_RW_MAX, 1000, HZ, &tape->best_dsc_rw_frequency, NULL);
4580 ide_add_setting(drive, "dsc_overlap", SETTING_RW, -1, -1, TYPE_BYTE, 0, 1, 1, 1, &drive->dsc_overlap, NULL);
4581 ide_add_setting(drive, "pipeline_head_speed_c",SETTING_READ, -1, -1, TYPE_INT, 0, 0xffff, 1, 1, &tape->controlled_pipeline_head_speed, NULL);
4582 ide_add_setting(drive, "pipeline_head_speed_u",SETTING_READ, -1, -1, TYPE_INT, 0, 0xffff, 1, 1, &tape->uncontrolled_pipeline_head_speed, NULL);
4583 ide_add_setting(drive, "avg_speed", SETTING_READ, -1, -1, TYPE_INT, 0, 0xffff, 1, 1, &tape->avg_speed, NULL);
4584 ide_add_setting(drive, "debug_level",SETTING_RW, -1, -1, TYPE_INT, 0, 0xffff, 1, 1, &tape->debug_level, NULL);
4587 /*
4588 * ide_setup is called to:
4590 * 1. Initialize our various state variables.
4591 * 2. Ask the tape for its capabilities.
4592 * 3. Allocate a buffer which will be used for data
4593 * transfer. The buffer size is chosen based on
4594 * the recommendation which we received in step (2).
4596 * Note that at this point ide.c already assigned us an irq, so that
4597 * we can queue requests here and wait for their completion.
4598 */
4599 static void idetape_setup (ide_drive_t *drive, idetape_tape_t *tape, int minor)
4601 unsigned long t1, tmid, tn, t;
4602 int speed;
4603 struct idetape_id_gcw gcw;
4604 int stage_size;
4605 struct sysinfo si;
4607 spin_lock_init(&tape->spinlock);
4608 drive->dsc_overlap = 1;
4609 #ifdef CONFIG_BLK_DEV_IDEPCI
4610 if (HWIF(drive)->pci_dev != NULL) {
4611 /*
4612 * These two ide-pci host adapters appear to need DSC overlap disabled.
4613 * This probably needs further analysis.
4614 */
4615 if ((HWIF(drive)->pci_dev->device == PCI_DEVICE_ID_ARTOP_ATP850UF) ||
4616 (HWIF(drive)->pci_dev->device == PCI_DEVICE_ID_TTI_HPT343)) {
4617 printk(KERN_INFO "ide-tape: %s: disabling DSC overlap\n", tape->name);
4618 drive->dsc_overlap = 0;
4621 #endif /* CONFIG_BLK_DEV_IDEPCI */
4622 /* Seagate Travan drives do not support DSC overlap. */
4623 if (strstr(drive->id->model, "Seagate STT3401"))
4624 drive->dsc_overlap = 0;
4625 tape->minor = minor;
4626 tape->name[0] = 'h';
4627 tape->name[1] = 't';
4628 tape->name[2] = '0' + minor;
4629 tape->chrdev_direction = idetape_direction_none;
4630 tape->pc = tape->pc_stack;
4631 tape->max_insert_speed = 10000;
4632 tape->speed_control = 1;
4633 *((unsigned short *) &gcw) = drive->id->config;
4634 if (gcw.drq_type == 1)
4635 set_bit(IDETAPE_DRQ_INTERRUPT, &tape->flags);
4637 tape->min_pipeline = tape->max_pipeline = tape->max_stages = 10;
4639 idetape_get_inquiry_results(drive);
4640 idetape_get_mode_sense_results(drive);
4641 idetape_get_blocksize_from_block_descriptor(drive);
4642 tape->user_bs_factor = 1;
4643 tape->stage_size = tape->capabilities.ctl * tape->tape_block_size;
4644 while (tape->stage_size > 0xffff) {
4645 printk(KERN_NOTICE "ide-tape: decreasing stage size\n");
4646 tape->capabilities.ctl /= 2;
4647 tape->stage_size = tape->capabilities.ctl * tape->tape_block_size;
4649 stage_size = tape->stage_size;
4650 tape->pages_per_stage = stage_size / PAGE_SIZE;
4651 if (stage_size % PAGE_SIZE) {
4652 tape->pages_per_stage++;
4653 tape->excess_bh_size = PAGE_SIZE - stage_size % PAGE_SIZE;
4656 /*
4657 * Select the "best" DSC read/write polling frequency
4658 * and pipeline size.
4659 */
4660 speed = max(tape->capabilities.speed, tape->capabilities.max_speed);
4662 tape->max_stages = speed * 1000 * 10 / tape->stage_size;
4664 /*
4665 * Limit memory use for pipeline to 10% of physical memory
4666 */
4667 si_meminfo(&si);
4668 if (tape->max_stages * tape->stage_size > si.totalram * si.mem_unit / 10)
4669 tape->max_stages = si.totalram * si.mem_unit / (10 * tape->stage_size);
4670 tape->max_stages = min(tape->max_stages, IDETAPE_MAX_PIPELINE_STAGES);
4671 tape->min_pipeline = min(tape->max_stages, IDETAPE_MIN_PIPELINE_STAGES);
4672 tape->max_pipeline = min(tape->max_stages * 2, IDETAPE_MAX_PIPELINE_STAGES);
4673 if (tape->max_stages == 0)
4674 tape->max_stages = tape->min_pipeline = tape->max_pipeline = 1;
4676 t1 = (tape->stage_size * HZ) / (speed * 1000);
4677 tmid = (tape->capabilities.buffer_size * 32 * HZ) / (speed * 125);
4678 tn = (IDETAPE_FIFO_THRESHOLD * tape->stage_size * HZ) / (speed * 1000);
4680 if (tape->max_stages)
4681 t = tn;
4682 else
4683 t = t1;
4685 /*
4686 * Ensure that the number we got makes sense; limit
4687 * it within IDETAPE_DSC_RW_MIN and IDETAPE_DSC_RW_MAX.
4688 */
4689 tape->best_dsc_rw_frequency = max_t(unsigned long, min_t(unsigned long, t, IDETAPE_DSC_RW_MAX), IDETAPE_DSC_RW_MIN);
4690 printk(KERN_INFO "ide-tape: %s <-> %s: %dKBps, %d*%dkB buffer, "
4691 "%dkB pipeline, %lums tDSC%s\n",
4692 drive->name, tape->name, tape->capabilities.speed,
4693 (tape->capabilities.buffer_size * 512) / tape->stage_size,
4694 tape->stage_size / 1024,
4695 tape->max_stages * tape->stage_size / 1024,
4696 tape->best_dsc_rw_frequency * 1000 / HZ,
4697 drive->using_dma ? ", DMA":"");
4699 idetape_add_settings(drive);
4702 static void ide_tape_remove(ide_drive_t *drive)
4704 idetape_tape_t *tape = drive->driver_data;
4706 ide_unregister_subdriver(drive, tape->driver);
4708 ide_unregister_region(tape->disk);
4710 ide_tape_put(tape);
4713 static void ide_tape_release(struct kref *kref)
4715 struct ide_tape_obj *tape = to_ide_tape(kref);
4716 ide_drive_t *drive = tape->drive;
4717 struct gendisk *g = tape->disk;
4719 BUG_ON(tape->first_stage != NULL || tape->merge_stage_size);
4721 drive->dsc_overlap = 0;
4722 drive->driver_data = NULL;
4723 class_device_destroy(idetape_sysfs_class,
4724 MKDEV(IDETAPE_MAJOR, tape->minor));
4725 class_device_destroy(idetape_sysfs_class,
4726 MKDEV(IDETAPE_MAJOR, tape->minor + 128));
4727 idetape_devs[tape->minor] = NULL;
4728 g->private_data = NULL;
4729 put_disk(g);
4730 kfree(tape);
4733 #ifdef CONFIG_PROC_FS
4735 static int proc_idetape_read_name
4736 (char *page, char **start, off_t off, int count, int *eof, void *data)
4738 ide_drive_t *drive = (ide_drive_t *) data;
4739 idetape_tape_t *tape = drive->driver_data;
4740 char *out = page;
4741 int len;
4743 len = sprintf(out, "%s\n", tape->name);
4744 PROC_IDE_READ_RETURN(page, start, off, count, eof, len);
4747 static ide_proc_entry_t idetape_proc[] = {
4748 { "capacity", S_IFREG|S_IRUGO, proc_ide_read_capacity, NULL },
4749 { "name", S_IFREG|S_IRUGO, proc_idetape_read_name, NULL },
4750 { NULL, 0, NULL, NULL }
4751 };
4753 #else
4755 #define idetape_proc NULL
4757 #endif
4759 static int ide_tape_probe(ide_drive_t *);
4761 static ide_driver_t idetape_driver = {
4762 .gen_driver = {
4763 .owner = THIS_MODULE,
4764 .name = "ide-tape",
4765 .bus = &ide_bus_type,
4766 },
4767 .probe = ide_tape_probe,
4768 .remove = ide_tape_remove,
4769 .version = IDETAPE_VERSION,
4770 .media = ide_tape,
4771 .supports_dsc_overlap = 1,
4772 .do_request = idetape_do_request,
4773 .end_request = idetape_end_request,
4774 .error = __ide_error,
4775 .abort = __ide_abort,
4776 .proc = idetape_proc,
4777 };
4779 /*
4780 * Our character device supporting functions, passed to register_chrdev.
4781 */
4782 static struct file_operations idetape_fops = {
4783 .owner = THIS_MODULE,
4784 .read = idetape_chrdev_read,
4785 .write = idetape_chrdev_write,
4786 .ioctl = idetape_chrdev_ioctl,
4787 .open = idetape_chrdev_open,
4788 .release = idetape_chrdev_release,
4789 };
4791 static int idetape_open(struct inode *inode, struct file *filp)
4793 struct gendisk *disk = inode->i_bdev->bd_disk;
4794 struct ide_tape_obj *tape;
4795 ide_drive_t *drive;
4797 if (!(tape = ide_tape_get(disk)))
4798 return -ENXIO;
4800 drive = tape->drive;
4802 drive->usage++;
4804 return 0;
4807 static int idetape_release(struct inode *inode, struct file *filp)
4809 struct gendisk *disk = inode->i_bdev->bd_disk;
4810 struct ide_tape_obj *tape = ide_tape_g(disk);
4811 ide_drive_t *drive = tape->drive;
4813 drive->usage--;
4815 ide_tape_put(tape);
4817 return 0;
4820 static int idetape_ioctl(struct inode *inode, struct file *file,
4821 unsigned int cmd, unsigned long arg)
4823 struct block_device *bdev = inode->i_bdev;
4824 struct ide_tape_obj *tape = ide_tape_g(bdev->bd_disk);
4825 ide_drive_t *drive = tape->drive;
4826 int err = generic_ide_ioctl(drive, file, bdev, cmd, arg);
4827 if (err == -EINVAL)
4828 err = idetape_blkdev_ioctl(drive, cmd, arg);
4829 return err;
4832 static struct block_device_operations idetape_block_ops = {
4833 .owner = THIS_MODULE,
4834 .open = idetape_open,
4835 .release = idetape_release,
4836 .ioctl = idetape_ioctl,
4837 };
4839 static int ide_tape_probe(ide_drive_t *drive)
4841 idetape_tape_t *tape;
4842 struct gendisk *g;
4843 int minor;
4845 if (!strstr("ide-tape", drive->driver_req))
4846 goto failed;
4847 if (!drive->present)
4848 goto failed;
4849 if (drive->media != ide_tape)
4850 goto failed;
4851 if (!idetape_identify_device (drive)) {
4852 printk(KERN_ERR "ide-tape: %s: not supported by this version of ide-tape\n", drive->name);
4853 goto failed;
4855 if (drive->scsi) {
4856 printk("ide-tape: passing drive %s to ide-scsi emulation.\n", drive->name);
4857 goto failed;
4859 if (strstr(drive->id->model, "OnStream DI-")) {
4860 printk(KERN_WARNING "ide-tape: Use drive %s with ide-scsi emulation and osst.\n", drive->name);
4861 printk(KERN_WARNING "ide-tape: OnStream support will be removed soon from ide-tape!\n");
4863 tape = (idetape_tape_t *) kzalloc (sizeof (idetape_tape_t), GFP_KERNEL);
4864 if (tape == NULL) {
4865 printk(KERN_ERR "ide-tape: %s: Can't allocate a tape structure\n", drive->name);
4866 goto failed;
4869 g = alloc_disk(1 << PARTN_BITS);
4870 if (!g)
4871 goto out_free_tape;
4873 ide_init_disk(g, drive);
4875 ide_register_subdriver(drive, &idetape_driver);
4877 kref_init(&tape->kref);
4879 tape->drive = drive;
4880 tape->driver = &idetape_driver;
4881 tape->disk = g;
4883 g->private_data = &tape->driver;
4885 drive->driver_data = tape;
4887 mutex_lock(&idetape_ref_mutex);
4888 for (minor = 0; idetape_devs[minor]; minor++)
4890 idetape_devs[minor] = tape;
4891 mutex_unlock(&idetape_ref_mutex);
4893 idetape_setup(drive, tape, minor);
4895 class_device_create(idetape_sysfs_class, NULL,
4896 MKDEV(IDETAPE_MAJOR, minor), &drive->gendev, "%s", tape->name);
4897 class_device_create(idetape_sysfs_class, NULL,
4898 MKDEV(IDETAPE_MAJOR, minor + 128), &drive->gendev, "n%s", tape->name);
4900 g->fops = &idetape_block_ops;
4901 ide_register_region(g);
4903 return 0;
4905 out_free_tape:
4906 kfree(tape);
4907 failed:
4908 return -ENODEV;
4911 MODULE_DESCRIPTION("ATAPI Streaming TAPE Driver");
4912 MODULE_LICENSE("GPL");
4914 static void __exit idetape_exit (void)
4916 driver_unregister(&idetape_driver.gen_driver);
4917 class_destroy(idetape_sysfs_class);
4918 unregister_chrdev(IDETAPE_MAJOR, "ht");
4921 static int __init idetape_init(void)
4923 int error = 1;
4924 idetape_sysfs_class = class_create(THIS_MODULE, "ide_tape");
4925 if (IS_ERR(idetape_sysfs_class)) {
4926 idetape_sysfs_class = NULL;
4927 printk(KERN_ERR "Unable to create sysfs class for ide tapes\n");
4928 error = -EBUSY;
4929 goto out;
4932 if (register_chrdev(IDETAPE_MAJOR, "ht", &idetape_fops)) {
4933 printk(KERN_ERR "ide-tape: Failed to register character device interface\n");
4934 error = -EBUSY;
4935 goto out_free_class;
4938 error = driver_register(&idetape_driver.gen_driver);
4939 if (error)
4940 goto out_free_driver;
4942 return 0;
4944 out_free_driver:
4945 driver_unregister(&idetape_driver.gen_driver);
4946 out_free_class:
4947 class_destroy(idetape_sysfs_class);
4948 out:
4949 return error;
4952 MODULE_ALIAS("ide:*m-tape*");
4953 module_init(idetape_init);
4954 module_exit(idetape_exit);
4955 MODULE_ALIAS_CHARDEV_MAJOR(IDETAPE_MAJOR);