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authorLinus Torvalds <torvalds@ppc970.osdl.org>2005-04-16 18:20:36 -0400
committerLinus Torvalds <torvalds@ppc970.osdl.org>2005-04-16 18:20:36 -0400
commit1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 (patch)
tree0bba044c4ce775e45a88a51686b5d9f90697ea9d /drivers/ide/ide-tape.c
Linux-2.6.12-rc2v2.6.12-rc2
Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
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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 */
15
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 */
323
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 */
400
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 */
424
425#define IDETAPE_VERSION "1.19"
426
427#include <linux/config.h>
428#include <linux/module.h>
429#include <linux/types.h>
430#include <linux/string.h>
431#include <linux/kernel.h>
432#include <linux/delay.h>
433#include <linux/timer.h>
434#include <linux/mm.h>
435#include <linux/interrupt.h>
436#include <linux/major.h>
437#include <linux/devfs_fs_kernel.h>
438#include <linux/errno.h>
439#include <linux/genhd.h>
440#include <linux/slab.h>
441#include <linux/pci.h>
442#include <linux/ide.h>
443#include <linux/smp_lock.h>
444#include <linux/completion.h>
445#include <linux/bitops.h>
446
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>
452
453/*
454 * partition
455 */
456typedef 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;
464
465/*
466 * DAT entry
467 */
468typedef struct os_dat_entry_s {
469 __u32 blk_sz;
470 __u16 blk_cnt;
471 __u8 flags;
472 __u8 reserved;
473} os_dat_entry_t;
474
475/*
476 * DAT
477 */
478#define OS_DAT_FLAGS_DATA (0xc)
479#define OS_DAT_FLAGS_MARK (0x1)
480
481typedef 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;
488
489#include <linux/mtio.h>
490
491/**************************** Tunable parameters *****************************/
492
493
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
512
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
534
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
542
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
549
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)
556
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)
563
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
572
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 */
603
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 */
614
615/*************************** End of tunable parameters ***********************/
616
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
627
628/*
629 * Read/Write error simulation
630 */
631#define SIMULATE_ERRORS 0
632
633/*
634 * For general magnetic tape device compatibility.
635 */
636typedef enum {
637 idetape_direction_none,
638 idetape_direction_read,
639 idetape_direction_write
640} idetape_chrdev_direction_t;
641
642struct idetape_bh {
643 unsigned short b_size;
644 atomic_t b_count;
645 struct idetape_bh *b_reqnext;
646 char *b_data;
647};
648
649/*
650 * Our view of a packet command.
651 */
652typedef 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;
668
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
684
685/*
686 * Capabilities and Mechanical Status Page
687 */
688typedef 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;
725
726/*
727 * Block Size Page
728 */
729typedef 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;
743
744/*
745 * A pipeline stage.
746 */
747typedef 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;
752
753/*
754 * REQUEST SENSE packet command result - Data Format.
755 */
756typedef 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;
777
778
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 */
784typedef struct ide_tape_obj {
785 ide_drive_t *drive;
786 ide_driver_t *driver;
787 struct gendisk *disk;
788 struct kref kref;
789
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;
816
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;
839
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;
848
849 /*
850 * Last error information
851 */
852 u8 sense_key, asc, ascq;
853
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;
862
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;
871
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;
894
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;
920
921 /* Status/Action flags: long for set_bit */
922 unsigned long flags;
923 /* protects the ide-tape queue */
924 spinlock_t spinlock;
925
926 /*
927 * Measures average tape speed
928 */
929 unsigned long avg_time;
930 int avg_size;
931 int avg_speed;
932
933 /* last sense information */
934 idetape_request_sense_result_t sense;
935
936 char vendor_id[10];
937 char product_id[18];
938 char firmware_revision[6];
939 int firmware_revision_num;
940
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;
947
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;
955
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;
967
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;
976
977 /*
978 * Measure tape still time, in milliseconds
979 */
980 unsigned long tape_still_time_begin;
981 int tape_still_time;
982
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;
999
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;
1013
1014static DECLARE_MUTEX(idetape_ref_sem);
1015
1016#define to_ide_tape(obj) container_of(obj, struct ide_tape_obj, kref)
1017
1018#define ide_tape_g(disk) \
1019 container_of((disk)->private_data, struct ide_tape_obj, driver)
1020
1021static struct ide_tape_obj *ide_tape_get(struct gendisk *disk)
1022{
1023 struct ide_tape_obj *tape = NULL;
1024
1025 down(&idetape_ref_sem);
1026 tape = ide_tape_g(disk);
1027 if (tape)
1028 kref_get(&tape->kref);
1029 up(&idetape_ref_sem);
1030 return tape;
1031}
1032
1033static void ide_tape_release(struct kref *);
1034
1035static void ide_tape_put(struct ide_tape_obj *tape)
1036{
1037 down(&idetape_ref_sem);
1038 kref_put(&tape->kref, ide_tape_release);
1039 up(&idetape_ref_sem);
1040}
1041
1042/*
1043 * Tape door status
1044 */
1045#define DOOR_UNLOCKED 0
1046#define DOOR_LOCKED 1
1047#define DOOR_EXPLICITLY_LOCKED 2
1048
1049/*
1050 * Tape flag bits values.
1051 */
1052#define IDETAPE_IGNORE_DSC 0
1053#define IDETAPE_ADDRESS_VALID 1 /* 0 When the tape position is unknown */
1054#define IDETAPE_BUSY 2 /* Device already opened */
1055#define IDETAPE_PIPELINE_ERROR 3 /* Error detected in a pipeline stage */
1056#define IDETAPE_DETECT_BS 4 /* Attempt to auto-detect the current user block size */
1057#define IDETAPE_FILEMARK 5 /* Currently on a filemark */
1058#define IDETAPE_DRQ_INTERRUPT 6 /* DRQ interrupt device */
1059#define IDETAPE_READ_ERROR 7
1060#define IDETAPE_PIPELINE_ACTIVE 8 /* pipeline active */
1061/* 0 = no tape is loaded, so we don't rewind after ejecting */
1062#define IDETAPE_MEDIUM_PRESENT 9
1063
1064/*
1065 * Supported ATAPI tape drives packet commands
1066 */
1067#define IDETAPE_TEST_UNIT_READY_CMD 0x00
1068#define IDETAPE_REWIND_CMD 0x01
1069#define IDETAPE_REQUEST_SENSE_CMD 0x03
1070#define IDETAPE_READ_CMD 0x08
1071#define IDETAPE_WRITE_CMD 0x0a
1072#define IDETAPE_WRITE_FILEMARK_CMD 0x10
1073#define IDETAPE_SPACE_CMD 0x11
1074#define IDETAPE_INQUIRY_CMD 0x12
1075#define IDETAPE_ERASE_CMD 0x19
1076#define IDETAPE_MODE_SENSE_CMD 0x1a
1077#define IDETAPE_MODE_SELECT_CMD 0x15
1078#define IDETAPE_LOAD_UNLOAD_CMD 0x1b
1079#define IDETAPE_PREVENT_CMD 0x1e
1080#define IDETAPE_LOCATE_CMD 0x2b
1081#define IDETAPE_READ_POSITION_CMD 0x34
1082#define IDETAPE_READ_BUFFER_CMD 0x3c
1083#define IDETAPE_SET_SPEED_CMD 0xbb
1084
1085/*
1086 * Some defines for the READ BUFFER command
1087 */
1088#define IDETAPE_RETRIEVE_FAULTY_BLOCK 6
1089
1090/*
1091 * Some defines for the SPACE command
1092 */
1093#define IDETAPE_SPACE_OVER_FILEMARK 1
1094#define IDETAPE_SPACE_TO_EOD 3
1095
1096/*
1097 * Some defines for the LOAD UNLOAD command
1098 */
1099#define IDETAPE_LU_LOAD_MASK 1
1100#define IDETAPE_LU_RETENSION_MASK 2
1101#define IDETAPE_LU_EOT_MASK 4
1102
1103/*
1104 * Special requests for our block device strategy routine.
1105 *
1106 * In order to service a character device command, we add special
1107 * requests to the tail of our block device request queue and wait
1108 * for their completion.
1109 */
1110
1111enum {
1112 REQ_IDETAPE_PC1 = (1 << 0), /* packet command (first stage) */
1113 REQ_IDETAPE_PC2 = (1 << 1), /* packet command (second stage) */
1114 REQ_IDETAPE_READ = (1 << 2),
1115 REQ_IDETAPE_WRITE = (1 << 3),
1116 REQ_IDETAPE_READ_BUFFER = (1 << 4),
1117};
1118
1119/*
1120 * Error codes which are returned in rq->errors to the higher part
1121 * of the driver.
1122 */
1123#define IDETAPE_ERROR_GENERAL 101
1124#define IDETAPE_ERROR_FILEMARK 102
1125#define IDETAPE_ERROR_EOD 103
1126
1127/*
1128 * The following is used to format the general configuration word of
1129 * the ATAPI IDENTIFY DEVICE command.
1130 */
1131struct idetape_id_gcw {
1132 unsigned packet_size :2; /* Packet Size */
1133 unsigned reserved234 :3; /* Reserved */
1134 unsigned drq_type :2; /* Command packet DRQ type */
1135 unsigned removable :1; /* Removable media */
1136 unsigned device_type :5; /* Device type */
1137 unsigned reserved13 :1; /* Reserved */
1138 unsigned protocol :2; /* Protocol type */
1139};
1140
1141/*
1142 * INQUIRY packet command - Data Format (From Table 6-8 of QIC-157C)
1143 */
1144typedef struct {
1145 unsigned device_type :5; /* Peripheral Device Type */
1146 unsigned reserved0_765 :3; /* Peripheral Qualifier - Reserved */
1147 unsigned reserved1_6t0 :7; /* Reserved */
1148 unsigned rmb :1; /* Removable Medium Bit */
1149 unsigned ansi_version :3; /* ANSI Version */
1150 unsigned ecma_version :3; /* ECMA Version */
1151 unsigned iso_version :2; /* ISO Version */
1152 unsigned response_format :4; /* Response Data Format */
1153 unsigned reserved3_45 :2; /* Reserved */
1154 unsigned reserved3_6 :1; /* TrmIOP - Reserved */
1155 unsigned reserved3_7 :1; /* AENC - Reserved */
1156 __u8 additional_length; /* Additional Length (total_length-4) */
1157 __u8 rsv5, rsv6, rsv7; /* Reserved */
1158 __u8 vendor_id[8]; /* Vendor Identification */
1159 __u8 product_id[16]; /* Product Identification */
1160 __u8 revision_level[4]; /* Revision Level */
1161 __u8 vendor_specific[20]; /* Vendor Specific - Optional */
1162 __u8 reserved56t95[40]; /* Reserved - Optional */
1163 /* Additional information may be returned */
1164} idetape_inquiry_result_t;
1165
1166/*
1167 * READ POSITION packet command - Data Format (From Table 6-57)
1168 */
1169typedef struct {
1170 unsigned reserved0_10 :2; /* Reserved */
1171 unsigned bpu :1; /* Block Position Unknown */
1172 unsigned reserved0_543 :3; /* Reserved */
1173 unsigned eop :1; /* End Of Partition */
1174 unsigned bop :1; /* Beginning Of Partition */
1175 u8 partition; /* Partition Number */
1176 u8 reserved2, reserved3; /* Reserved */
1177 u32 first_block; /* First Block Location */
1178 u32 last_block; /* Last Block Location (Optional) */
1179 u8 reserved12; /* Reserved */
1180 u8 blocks_in_buffer[3]; /* Blocks In Buffer - (Optional) */
1181 u32 bytes_in_buffer; /* Bytes In Buffer (Optional) */
1182} idetape_read_position_result_t;
1183
1184/*
1185 * Follows structures which are related to the SELECT SENSE / MODE SENSE
1186 * packet commands. Those packet commands are still not supported
1187 * by ide-tape.
1188 */
1189#define IDETAPE_BLOCK_DESCRIPTOR 0
1190#define IDETAPE_CAPABILITIES_PAGE 0x2a
1191#define IDETAPE_PARAMTR_PAGE 0x2b /* Onstream DI-x0 only */
1192#define IDETAPE_BLOCK_SIZE_PAGE 0x30
1193#define IDETAPE_BUFFER_FILLING_PAGE 0x33
1194
1195/*
1196 * Mode Parameter Header for the MODE SENSE packet command
1197 */
1198typedef struct {
1199 __u8 mode_data_length; /* Length of the following data transfer */
1200 __u8 medium_type; /* Medium Type */
1201 __u8 dsp; /* Device Specific Parameter */
1202 __u8 bdl; /* Block Descriptor Length */
1203#if 0
1204 /* data transfer page */
1205 __u8 page_code :6;
1206 __u8 reserved0_6 :1;
1207 __u8 ps :1; /* parameters saveable */
1208 __u8 page_length; /* page Length == 0x02 */
1209 __u8 reserved2;
1210 __u8 read32k :1; /* 32k blk size (data only) */
1211 __u8 read32k5 :1; /* 32.5k blk size (data&AUX) */
1212 __u8 reserved3_23 :2;
1213 __u8 write32k :1; /* 32k blk size (data only) */
1214 __u8 write32k5 :1; /* 32.5k blk size (data&AUX) */
1215 __u8 reserved3_6 :1;
1216 __u8 streaming :1; /* streaming mode enable */
1217#endif
1218} idetape_mode_parameter_header_t;
1219
1220/*
1221 * Mode Parameter Block Descriptor the MODE SENSE packet command
1222 *
1223 * Support for block descriptors is optional.
1224 */
1225typedef struct {
1226 __u8 density_code; /* Medium density code */
1227 __u8 blocks[3]; /* Number of blocks */
1228 __u8 reserved4; /* Reserved */
1229 __u8 length[3]; /* Block Length */
1230} idetape_parameter_block_descriptor_t;
1231
1232/*
1233 * The Data Compression Page, as returned by the MODE SENSE packet command.
1234 */
1235typedef struct {
1236 unsigned page_code :6; /* Page Code - Should be 0xf */
1237 unsigned reserved0 :1; /* Reserved */
1238 unsigned ps :1;
1239 __u8 page_length; /* Page Length - Should be 14 */
1240 unsigned reserved2 :6; /* Reserved */
1241 unsigned dcc :1; /* Data Compression Capable */
1242 unsigned dce :1; /* Data Compression Enable */
1243 unsigned reserved3 :5; /* Reserved */
1244 unsigned red :2; /* Report Exception on Decompression */
1245 unsigned dde :1; /* Data Decompression Enable */
1246 __u32 ca; /* Compression Algorithm */
1247 __u32 da; /* Decompression Algorithm */
1248 __u8 reserved[4]; /* Reserved */
1249} idetape_data_compression_page_t;
1250
1251/*
1252 * The Medium Partition Page, as returned by the MODE SENSE packet command.
1253 */
1254typedef struct {
1255 unsigned page_code :6; /* Page Code - Should be 0x11 */
1256 unsigned reserved1_6 :1; /* Reserved */
1257 unsigned ps :1;
1258 __u8 page_length; /* Page Length - Should be 6 */
1259 __u8 map; /* Maximum Additional Partitions - Should be 0 */
1260 __u8 apd; /* Additional Partitions Defined - Should be 0 */
1261 unsigned reserved4_012 :3; /* Reserved */
1262 unsigned psum :2; /* Should be 0 */
1263 unsigned idp :1; /* Should be 0 */
1264 unsigned sdp :1; /* Should be 0 */
1265 unsigned fdp :1; /* Fixed Data Partitions */
1266 __u8 mfr; /* Medium Format Recognition */
1267 __u8 reserved[2]; /* Reserved */
1268} idetape_medium_partition_page_t;
1269
1270/*
1271 * Run time configurable parameters.
1272 */
1273typedef struct {
1274 int dsc_rw_frequency;
1275 int dsc_media_access_frequency;
1276 int nr_stages;
1277} idetape_config_t;
1278
1279/*
1280 * The variables below are used for the character device interface.
1281 * Additional state variables are defined in our ide_drive_t structure.
1282 */
1283static struct ide_tape_obj * idetape_devs[MAX_HWIFS * MAX_DRIVES];
1284
1285#define ide_tape_f(file) ((file)->private_data)
1286
1287static struct ide_tape_obj *ide_tape_chrdev_get(unsigned int i)
1288{
1289 struct ide_tape_obj *tape = NULL;
1290
1291 down(&idetape_ref_sem);
1292 tape = idetape_devs[i];
1293 if (tape)
1294 kref_get(&tape->kref);
1295 up(&idetape_ref_sem);
1296 return tape;
1297}
1298
1299/*
1300 * Function declarations
1301 *
1302 */
1303static int idetape_chrdev_release (struct inode *inode, struct file *filp);
1304static void idetape_write_release (ide_drive_t *drive, unsigned int minor);
1305
1306/*
1307 * Too bad. The drive wants to send us data which we are not ready to accept.
1308 * Just throw it away.
1309 */
1310static void idetape_discard_data (ide_drive_t *drive, unsigned int bcount)
1311{
1312 while (bcount--)
1313 (void) HWIF(drive)->INB(IDE_DATA_REG);
1314}
1315
1316static void idetape_input_buffers (ide_drive_t *drive, idetape_pc_t *pc, unsigned int bcount)
1317{
1318 struct idetape_bh *bh = pc->bh;
1319 int count;
1320
1321 while (bcount) {
1322#if IDETAPE_DEBUG_BUGS
1323 if (bh == NULL) {
1324 printk(KERN_ERR "ide-tape: bh == NULL in "
1325 "idetape_input_buffers\n");
1326 idetape_discard_data(drive, bcount);
1327 return;
1328 }
1329#endif /* IDETAPE_DEBUG_BUGS */
1330 count = min((unsigned int)(bh->b_size - atomic_read(&bh->b_count)), bcount);
1331 HWIF(drive)->atapi_input_bytes(drive, bh->b_data + atomic_read(&bh->b_count), count);
1332 bcount -= count;
1333 atomic_add(count, &bh->b_count);
1334 if (atomic_read(&bh->b_count) == bh->b_size) {
1335 bh = bh->b_reqnext;
1336 if (bh)
1337 atomic_set(&bh->b_count, 0);
1338 }
1339 }
1340 pc->bh = bh;
1341}
1342
1343static void idetape_output_buffers (ide_drive_t *drive, idetape_pc_t *pc, unsigned int bcount)
1344{
1345 struct idetape_bh *bh = pc->bh;
1346 int count;
1347
1348 while (bcount) {
1349#if IDETAPE_DEBUG_BUGS
1350 if (bh == NULL) {
1351 printk(KERN_ERR "ide-tape: bh == NULL in "
1352 "idetape_output_buffers\n");
1353 return;
1354 }
1355#endif /* IDETAPE_DEBUG_BUGS */
1356 count = min((unsigned int)pc->b_count, (unsigned int)bcount);
1357 HWIF(drive)->atapi_output_bytes(drive, pc->b_data, count);
1358 bcount -= count;
1359 pc->b_data += count;
1360 pc->b_count -= count;
1361 if (!pc->b_count) {
1362 pc->bh = bh = bh->b_reqnext;
1363 if (bh) {
1364 pc->b_data = bh->b_data;
1365 pc->b_count = atomic_read(&bh->b_count);
1366 }
1367 }
1368 }
1369}
1370
1371static void idetape_update_buffers (idetape_pc_t *pc)
1372{
1373 struct idetape_bh *bh = pc->bh;
1374 int count;
1375 unsigned int bcount = pc->actually_transferred;
1376
1377 if (test_bit(PC_WRITING, &pc->flags))
1378 return;
1379 while (bcount) {
1380#if IDETAPE_DEBUG_BUGS
1381 if (bh == NULL) {
1382 printk(KERN_ERR "ide-tape: bh == NULL in "
1383 "idetape_update_buffers\n");
1384 return;
1385 }
1386#endif /* IDETAPE_DEBUG_BUGS */
1387 count = min((unsigned int)bh->b_size, (unsigned int)bcount);
1388 atomic_set(&bh->b_count, count);
1389 if (atomic_read(&bh->b_count) == bh->b_size)
1390 bh = bh->b_reqnext;
1391 bcount -= count;
1392 }
1393 pc->bh = bh;
1394}
1395
1396/*
1397 * idetape_next_pc_storage returns a pointer to a place in which we can
1398 * safely store a packet command, even though we intend to leave the
1399 * driver. A storage space for a maximum of IDETAPE_PC_STACK packet
1400 * commands is allocated at initialization time.
1401 */
1402static idetape_pc_t *idetape_next_pc_storage (ide_drive_t *drive)
1403{
1404 idetape_tape_t *tape = drive->driver_data;
1405
1406#if IDETAPE_DEBUG_LOG
1407 if (tape->debug_level >= 5)
1408 printk(KERN_INFO "ide-tape: pc_stack_index=%d\n",
1409 tape->pc_stack_index);
1410#endif /* IDETAPE_DEBUG_LOG */
1411 if (tape->pc_stack_index == IDETAPE_PC_STACK)
1412 tape->pc_stack_index=0;
1413 return (&tape->pc_stack[tape->pc_stack_index++]);
1414}
1415
1416/*
1417 * idetape_next_rq_storage is used along with idetape_next_pc_storage.
1418 * Since we queue packet commands in the request queue, we need to
1419 * allocate a request, along with the allocation of a packet command.
1420 */
1421
1422/**************************************************************
1423 * *
1424 * This should get fixed to use kmalloc(.., GFP_ATOMIC) *
1425 * followed later on by kfree(). -ml *
1426 * *
1427 **************************************************************/
1428
1429static struct request *idetape_next_rq_storage (ide_drive_t *drive)
1430{
1431 idetape_tape_t *tape = drive->driver_data;
1432
1433#if IDETAPE_DEBUG_LOG
1434 if (tape->debug_level >= 5)
1435 printk(KERN_INFO "ide-tape: rq_stack_index=%d\n",
1436 tape->rq_stack_index);
1437#endif /* IDETAPE_DEBUG_LOG */
1438 if (tape->rq_stack_index == IDETAPE_PC_STACK)
1439 tape->rq_stack_index=0;
1440 return (&tape->rq_stack[tape->rq_stack_index++]);
1441}
1442
1443/*
1444 * idetape_init_pc initializes a packet command.
1445 */
1446static void idetape_init_pc (idetape_pc_t *pc)
1447{
1448 memset(pc->c, 0, 12);
1449 pc->retries = 0;
1450 pc->flags = 0;
1451 pc->request_transfer = 0;
1452 pc->buffer = pc->pc_buffer;
1453 pc->buffer_size = IDETAPE_PC_BUFFER_SIZE;
1454 pc->bh = NULL;
1455 pc->b_data = NULL;
1456}
1457
1458/*
1459 * idetape_analyze_error is called on each failed packet command retry
1460 * to analyze the request sense. We currently do not utilize this
1461 * information.
1462 */
1463static void idetape_analyze_error (ide_drive_t *drive, idetape_request_sense_result_t *result)
1464{
1465 idetape_tape_t *tape = drive->driver_data;
1466 idetape_pc_t *pc = tape->failed_pc;
1467
1468 tape->sense = *result;
1469 tape->sense_key = result->sense_key;
1470 tape->asc = result->asc;
1471 tape->ascq = result->ascq;
1472#if IDETAPE_DEBUG_LOG
1473 /*
1474 * Without debugging, we only log an error if we decided to
1475 * give up retrying.
1476 */
1477 if (tape->debug_level >= 1)
1478 printk(KERN_INFO "ide-tape: pc = %x, sense key = %x, "
1479 "asc = %x, ascq = %x\n",
1480 pc->c[0], result->sense_key,
1481 result->asc, result->ascq);
1482#endif /* IDETAPE_DEBUG_LOG */
1483
1484 /*
1485 * Correct pc->actually_transferred by asking the tape.
1486 */
1487 if (test_bit(PC_DMA_ERROR, &pc->flags)) {
1488 pc->actually_transferred = pc->request_transfer - tape->tape_block_size * ntohl(get_unaligned(&result->information));
1489 idetape_update_buffers(pc);
1490 }
1491
1492 /*
1493 * If error was the result of a zero-length read or write command,
1494 * with sense key=5, asc=0x22, ascq=0, let it slide. Some drives
1495 * (i.e. Seagate STT3401A Travan) don't support 0-length read/writes.
1496 */
1497 if ((pc->c[0] == IDETAPE_READ_CMD || pc->c[0] == IDETAPE_WRITE_CMD)
1498 && pc->c[4] == 0 && pc->c[3] == 0 && pc->c[2] == 0) { /* length==0 */
1499 if (result->sense_key == 5) {
1500 /* don't report an error, everything's ok */
1501 pc->error = 0;
1502 /* don't retry read/write */
1503 set_bit(PC_ABORT, &pc->flags);
1504 }
1505 }
1506 if (pc->c[0] == IDETAPE_READ_CMD && result->filemark) {
1507 pc->error = IDETAPE_ERROR_FILEMARK;
1508 set_bit(PC_ABORT, &pc->flags);
1509 }
1510 if (pc->c[0] == IDETAPE_WRITE_CMD) {
1511 if (result->eom ||
1512 (result->sense_key == 0xd && result->asc == 0x0 &&
1513 result->ascq == 0x2)) {
1514 pc->error = IDETAPE_ERROR_EOD;
1515 set_bit(PC_ABORT, &pc->flags);
1516 }
1517 }
1518 if (pc->c[0] == IDETAPE_READ_CMD || pc->c[0] == IDETAPE_WRITE_CMD) {
1519 if (result->sense_key == 8) {
1520 pc->error = IDETAPE_ERROR_EOD;
1521 set_bit(PC_ABORT, &pc->flags);
1522 }
1523 if (!test_bit(PC_ABORT, &pc->flags) &&
1524 pc->actually_transferred)
1525 pc->retries = IDETAPE_MAX_PC_RETRIES + 1;
1526 }
1527}
1528
1529/*
1530 * idetape_active_next_stage will declare the next stage as "active".
1531 */
1532static void idetape_active_next_stage (ide_drive_t *drive)
1533{
1534 idetape_tape_t *tape = drive->driver_data;
1535 idetape_stage_t *stage = tape->next_stage;
1536 struct request *rq = &stage->rq;
1537
1538#if IDETAPE_DEBUG_LOG
1539 if (tape->debug_level >= 4)
1540 printk(KERN_INFO "ide-tape: Reached idetape_active_next_stage\n");
1541#endif /* IDETAPE_DEBUG_LOG */
1542#if IDETAPE_DEBUG_BUGS
1543 if (stage == NULL) {
1544 printk(KERN_ERR "ide-tape: bug: Trying to activate a non existing stage\n");
1545 return;
1546 }
1547#endif /* IDETAPE_DEBUG_BUGS */
1548
1549 rq->rq_disk = tape->disk;
1550 rq->buffer = NULL;
1551 rq->special = (void *)stage->bh;
1552 tape->active_data_request = rq;
1553 tape->active_stage = stage;
1554 tape->next_stage = stage->next;
1555}
1556
1557/*
1558 * idetape_increase_max_pipeline_stages is a part of the feedback
1559 * loop which tries to find the optimum number of stages. In the
1560 * feedback loop, we are starting from a minimum maximum number of
1561 * stages, and if we sense that the pipeline is empty, we try to
1562 * increase it, until we reach the user compile time memory limit.
1563 */
1564static void idetape_increase_max_pipeline_stages (ide_drive_t *drive)
1565{
1566 idetape_tape_t *tape = drive->driver_data;
1567 int increase = (tape->max_pipeline - tape->min_pipeline) / 10;
1568
1569#if IDETAPE_DEBUG_LOG
1570 if (tape->debug_level >= 4)
1571 printk (KERN_INFO "ide-tape: Reached idetape_increase_max_pipeline_stages\n");
1572#endif /* IDETAPE_DEBUG_LOG */
1573
1574 tape->max_stages += max(increase, 1);
1575 tape->max_stages = max(tape->max_stages, tape->min_pipeline);
1576 tape->max_stages = min(tape->max_stages, tape->max_pipeline);
1577}
1578
1579/*
1580 * idetape_kfree_stage calls kfree to completely free a stage, along with
1581 * its related buffers.
1582 */
1583static void __idetape_kfree_stage (idetape_stage_t *stage)
1584{
1585 struct idetape_bh *prev_bh, *bh = stage->bh;
1586 int size;
1587
1588 while (bh != NULL) {
1589 if (bh->b_data != NULL) {
1590 size = (int) bh->b_size;
1591 while (size > 0) {
1592 free_page((unsigned long) bh->b_data);
1593 size -= PAGE_SIZE;
1594 bh->b_data += PAGE_SIZE;
1595 }
1596 }
1597 prev_bh = bh;
1598 bh = bh->b_reqnext;
1599 kfree(prev_bh);
1600 }
1601 kfree(stage);
1602}
1603
1604static void idetape_kfree_stage (idetape_tape_t *tape, idetape_stage_t *stage)
1605{
1606 __idetape_kfree_stage(stage);
1607}
1608
1609/*
1610 * idetape_remove_stage_head removes tape->first_stage from the pipeline.
1611 * The caller should avoid race conditions.
1612 */
1613static void idetape_remove_stage_head (ide_drive_t *drive)
1614{
1615 idetape_tape_t *tape = drive->driver_data;
1616 idetape_stage_t *stage;
1617
1618#if IDETAPE_DEBUG_LOG
1619 if (tape->debug_level >= 4)
1620 printk(KERN_INFO "ide-tape: Reached idetape_remove_stage_head\n");
1621#endif /* IDETAPE_DEBUG_LOG */
1622#if IDETAPE_DEBUG_BUGS
1623 if (tape->first_stage == NULL) {
1624 printk(KERN_ERR "ide-tape: bug: tape->first_stage is NULL\n");
1625 return;
1626 }
1627 if (tape->active_stage == tape->first_stage) {
1628 printk(KERN_ERR "ide-tape: bug: Trying to free our active pipeline stage\n");
1629 return;
1630 }
1631#endif /* IDETAPE_DEBUG_BUGS */
1632 stage = tape->first_stage;
1633 tape->first_stage = stage->next;
1634 idetape_kfree_stage(tape, stage);
1635 tape->nr_stages--;
1636 if (tape->first_stage == NULL) {
1637 tape->last_stage = NULL;
1638#if IDETAPE_DEBUG_BUGS
1639 if (tape->next_stage != NULL)
1640 printk(KERN_ERR "ide-tape: bug: tape->next_stage != NULL\n");
1641 if (tape->nr_stages)
1642 printk(KERN_ERR "ide-tape: bug: nr_stages should be 0 now\n");
1643#endif /* IDETAPE_DEBUG_BUGS */
1644 }
1645}
1646
1647/*
1648 * This will free all the pipeline stages starting from new_last_stage->next
1649 * to the end of the list, and point tape->last_stage to new_last_stage.
1650 */
1651static void idetape_abort_pipeline(ide_drive_t *drive,
1652 idetape_stage_t *new_last_stage)
1653{
1654 idetape_tape_t *tape = drive->driver_data;
1655 idetape_stage_t *stage = new_last_stage->next;
1656 idetape_stage_t *nstage;
1657
1658#if IDETAPE_DEBUG_LOG
1659 if (tape->debug_level >= 4)
1660 printk(KERN_INFO "ide-tape: %s: idetape_abort_pipeline called\n", tape->name);
1661#endif
1662 while (stage) {
1663 nstage = stage->next;
1664 idetape_kfree_stage(tape, stage);
1665 --tape->nr_stages;
1666 --tape->nr_pending_stages;
1667 stage = nstage;
1668 }
1669 if (new_last_stage)
1670 new_last_stage->next = NULL;
1671 tape->last_stage = new_last_stage;
1672 tape->next_stage = NULL;
1673}
1674
1675/*
1676 * idetape_end_request is used to finish servicing a request, and to
1677 * insert a pending pipeline request into the main device queue.
1678 */
1679static int idetape_end_request(ide_drive_t *drive, int uptodate, int nr_sects)
1680{
1681 struct request *rq = HWGROUP(drive)->rq;
1682 idetape_tape_t *tape = drive->driver_data;
1683 unsigned long flags;
1684 int error;
1685 int remove_stage = 0;
1686 idetape_stage_t *active_stage;
1687
1688#if IDETAPE_DEBUG_LOG
1689 if (tape->debug_level >= 4)
1690 printk(KERN_INFO "ide-tape: Reached idetape_end_request\n");
1691#endif /* IDETAPE_DEBUG_LOG */
1692
1693 switch (uptodate) {
1694 case 0: error = IDETAPE_ERROR_GENERAL; break;
1695 case 1: error = 0; break;
1696 default: error = uptodate;
1697 }
1698 rq->errors = error;
1699 if (error)
1700 tape->failed_pc = NULL;
1701
1702 spin_lock_irqsave(&tape->spinlock, flags);
1703
1704 /* The request was a pipelined data transfer request */
1705 if (tape->active_data_request == rq) {
1706 active_stage = tape->active_stage;
1707 tape->active_stage = NULL;
1708 tape->active_data_request = NULL;
1709 tape->nr_pending_stages--;
1710 if (rq->cmd[0] & REQ_IDETAPE_WRITE) {
1711 remove_stage = 1;
1712 if (error) {
1713 set_bit(IDETAPE_PIPELINE_ERROR, &tape->flags);
1714 if (error == IDETAPE_ERROR_EOD)
1715 idetape_abort_pipeline(drive, active_stage);
1716 }
1717 } else if (rq->cmd[0] & REQ_IDETAPE_READ) {
1718 if (error == IDETAPE_ERROR_EOD) {
1719 set_bit(IDETAPE_PIPELINE_ERROR, &tape->flags);
1720 idetape_abort_pipeline(drive, active_stage);
1721 }
1722 }
1723 if (tape->next_stage != NULL) {
1724 idetape_active_next_stage(drive);
1725
1726 /*
1727 * Insert the next request into the request queue.
1728 */
1729 (void) ide_do_drive_cmd(drive, tape->active_data_request, ide_end);
1730 } else if (!error) {
1731 idetape_increase_max_pipeline_stages(drive);
1732 }
1733 }
1734 ide_end_drive_cmd(drive, 0, 0);
1735// blkdev_dequeue_request(rq);
1736// drive->rq = NULL;
1737// end_that_request_last(rq);
1738
1739 if (remove_stage)
1740 idetape_remove_stage_head(drive);
1741 if (tape->active_data_request == NULL)
1742 clear_bit(IDETAPE_PIPELINE_ACTIVE, &tape->flags);
1743 spin_unlock_irqrestore(&tape->spinlock, flags);
1744 return 0;
1745}
1746
1747static ide_startstop_t idetape_request_sense_callback (ide_drive_t *drive)
1748{
1749 idetape_tape_t *tape = drive->driver_data;
1750
1751#if IDETAPE_DEBUG_LOG
1752 if (tape->debug_level >= 4)
1753 printk(KERN_INFO "ide-tape: Reached idetape_request_sense_callback\n");
1754#endif /* IDETAPE_DEBUG_LOG */
1755 if (!tape->pc->error) {
1756 idetape_analyze_error(drive, (idetape_request_sense_result_t *) tape->pc->buffer);
1757 idetape_end_request(drive, 1, 0);
1758 } else {
1759 printk(KERN_ERR "ide-tape: Error in REQUEST SENSE itself - Aborting request!\n");
1760 idetape_end_request(drive, 0, 0);
1761 }
1762 return ide_stopped;
1763}
1764
1765static void idetape_create_request_sense_cmd (idetape_pc_t *pc)
1766{
1767 idetape_init_pc(pc);
1768 pc->c[0] = IDETAPE_REQUEST_SENSE_CMD;
1769 pc->c[4] = 20;
1770 pc->request_transfer = 20;
1771 pc->callback = &idetape_request_sense_callback;
1772}
1773
1774static void idetape_init_rq(struct request *rq, u8 cmd)
1775{
1776 memset(rq, 0, sizeof(*rq));
1777 rq->flags = REQ_SPECIAL;
1778 rq->cmd[0] = cmd;
1779}
1780
1781/*
1782 * idetape_queue_pc_head generates a new packet command request in front
1783 * of the request queue, before the current request, so that it will be
1784 * processed immediately, on the next pass through the driver.
1785 *
1786 * idetape_queue_pc_head is called from the request handling part of
1787 * the driver (the "bottom" part). Safe storage for the request should
1788 * be allocated with idetape_next_pc_storage and idetape_next_rq_storage
1789 * before calling idetape_queue_pc_head.
1790 *
1791 * Memory for those requests is pre-allocated at initialization time, and
1792 * is limited to IDETAPE_PC_STACK requests. We assume that we have enough
1793 * space for the maximum possible number of inter-dependent packet commands.
1794 *
1795 * The higher level of the driver - The ioctl handler and the character
1796 * device handling functions should queue request to the lower level part
1797 * and wait for their completion using idetape_queue_pc_tail or
1798 * idetape_queue_rw_tail.
1799 */
1800static void idetape_queue_pc_head (ide_drive_t *drive, idetape_pc_t *pc,struct request *rq)
1801{
1802 struct ide_tape_obj *tape = drive->driver_data;
1803
1804 idetape_init_rq(rq, REQ_IDETAPE_PC1);
1805 rq->buffer = (char *) pc;
1806 rq->rq_disk = tape->disk;
1807 (void) ide_do_drive_cmd(drive, rq, ide_preempt);
1808}
1809
1810/*
1811 * idetape_retry_pc is called when an error was detected during the
1812 * last packet command. We queue a request sense packet command in
1813 * the head of the request list.
1814 */
1815static ide_startstop_t idetape_retry_pc (ide_drive_t *drive)
1816{
1817 idetape_tape_t *tape = drive->driver_data;
1818 idetape_pc_t *pc;
1819 struct request *rq;
1820 atapi_error_t error;
1821
1822 error.all = HWIF(drive)->INB(IDE_ERROR_REG);
1823 pc = idetape_next_pc_storage(drive);
1824 rq = idetape_next_rq_storage(drive);
1825 idetape_create_request_sense_cmd(pc);
1826 set_bit(IDETAPE_IGNORE_DSC, &tape->flags);
1827 idetape_queue_pc_head(drive, pc, rq);
1828 return ide_stopped;
1829}
1830
1831/*
1832 * idetape_postpone_request postpones the current request so that
1833 * ide.c will be able to service requests from another device on
1834 * the same hwgroup while we are polling for DSC.
1835 */
1836static void idetape_postpone_request (ide_drive_t *drive)
1837{
1838 idetape_tape_t *tape = drive->driver_data;
1839
1840#if IDETAPE_DEBUG_LOG
1841 if (tape->debug_level >= 4)
1842 printk(KERN_INFO "ide-tape: idetape_postpone_request\n");
1843#endif
1844 tape->postponed_rq = HWGROUP(drive)->rq;
1845 ide_stall_queue(drive, tape->dsc_polling_frequency);
1846}
1847
1848/*
1849 * idetape_pc_intr is the usual interrupt handler which will be called
1850 * during a packet command. We will transfer some of the data (as
1851 * requested by the drive) and will re-point interrupt handler to us.
1852 * When data transfer is finished, we will act according to the
1853 * algorithm described before idetape_issue_packet_command.
1854 *
1855 */
1856static ide_startstop_t idetape_pc_intr (ide_drive_t *drive)
1857{
1858 ide_hwif_t *hwif = drive->hwif;
1859 idetape_tape_t *tape = drive->driver_data;
1860 atapi_status_t status;
1861 atapi_bcount_t bcount;
1862 atapi_ireason_t ireason;
1863 idetape_pc_t *pc = tape->pc;
1864
1865 unsigned int temp;
1866#if SIMULATE_ERRORS
1867 static int error_sim_count = 0;
1868#endif
1869
1870#if IDETAPE_DEBUG_LOG
1871 if (tape->debug_level >= 4)
1872 printk(KERN_INFO "ide-tape: Reached idetape_pc_intr "
1873 "interrupt handler\n");
1874#endif /* IDETAPE_DEBUG_LOG */
1875
1876 /* Clear the interrupt */
1877 status.all = HWIF(drive)->INB(IDE_STATUS_REG);
1878
1879 if (test_bit(PC_DMA_IN_PROGRESS, &pc->flags)) {
1880 if (HWIF(drive)->ide_dma_end(drive) || status.b.check) {
1881 /*
1882 * A DMA error is sometimes expected. For example,
1883 * if the tape is crossing a filemark during a
1884 * READ command, it will issue an irq and position
1885 * itself before the filemark, so that only a partial
1886 * data transfer will occur (which causes the DMA
1887 * error). In that case, we will later ask the tape
1888 * how much bytes of the original request were
1889 * actually transferred (we can't receive that
1890 * information from the DMA engine on most chipsets).
1891 */
1892
1893 /*
1894 * On the contrary, a DMA error is never expected;
1895 * it usually indicates a hardware error or abort.
1896 * If the tape crosses a filemark during a READ
1897 * command, it will issue an irq and position itself
1898 * after the filemark (not before). Only a partial
1899 * data transfer will occur, but no DMA error.
1900 * (AS, 19 Apr 2001)
1901 */
1902 set_bit(PC_DMA_ERROR, &pc->flags);
1903 } else {
1904 pc->actually_transferred = pc->request_transfer;
1905 idetape_update_buffers(pc);
1906 }
1907#if IDETAPE_DEBUG_LOG
1908 if (tape->debug_level >= 4)
1909 printk(KERN_INFO "ide-tape: DMA finished\n");
1910#endif /* IDETAPE_DEBUG_LOG */
1911 }
1912
1913 /* No more interrupts */
1914 if (!status.b.drq) {
1915#if IDETAPE_DEBUG_LOG
1916 if (tape->debug_level >= 2)
1917 printk(KERN_INFO "ide-tape: Packet command completed, %d bytes transferred\n", pc->actually_transferred);
1918#endif /* IDETAPE_DEBUG_LOG */
1919 clear_bit(PC_DMA_IN_PROGRESS, &pc->flags);
1920
1921 local_irq_enable();
1922
1923#if SIMULATE_ERRORS
1924 if ((pc->c[0] == IDETAPE_WRITE_CMD ||
1925 pc->c[0] == IDETAPE_READ_CMD) &&
1926 (++error_sim_count % 100) == 0) {
1927 printk(KERN_INFO "ide-tape: %s: simulating error\n",
1928 tape->name);
1929 status.b.check = 1;
1930 }
1931#endif
1932 if (status.b.check && pc->c[0] == IDETAPE_REQUEST_SENSE_CMD)
1933 status.b.check = 0;
1934 if (status.b.check || test_bit(PC_DMA_ERROR, &pc->flags)) { /* Error detected */
1935#if IDETAPE_DEBUG_LOG
1936 if (tape->debug_level >= 1)
1937 printk(KERN_INFO "ide-tape: %s: I/O error\n",
1938 tape->name);
1939#endif /* IDETAPE_DEBUG_LOG */
1940 if (pc->c[0] == IDETAPE_REQUEST_SENSE_CMD) {
1941 printk(KERN_ERR "ide-tape: I/O error in request sense command\n");
1942 return ide_do_reset(drive);
1943 }
1944#if IDETAPE_DEBUG_LOG
1945 if (tape->debug_level >= 1)
1946 printk(KERN_INFO "ide-tape: [cmd %x]: check condition\n", pc->c[0]);
1947#endif
1948 /* Retry operation */
1949 return idetape_retry_pc(drive);
1950 }
1951 pc->error = 0;
1952 if (test_bit(PC_WAIT_FOR_DSC, &pc->flags) &&
1953 !status.b.dsc) {
1954 /* Media access command */
1955 tape->dsc_polling_start = jiffies;
1956 tape->dsc_polling_frequency = IDETAPE_DSC_MA_FAST;
1957 tape->dsc_timeout = jiffies + IDETAPE_DSC_MA_TIMEOUT;
1958 /* Allow ide.c to handle other requests */
1959 idetape_postpone_request(drive);
1960 return ide_stopped;
1961 }
1962 if (tape->failed_pc == pc)
1963 tape->failed_pc = NULL;
1964 /* Command finished - Call the callback function */
1965 return pc->callback(drive);
1966 }
1967 if (test_and_clear_bit(PC_DMA_IN_PROGRESS, &pc->flags)) {
1968 printk(KERN_ERR "ide-tape: The tape wants to issue more "
1969 "interrupts in DMA mode\n");
1970 printk(KERN_ERR "ide-tape: DMA disabled, reverting to PIO\n");
1971 (void)__ide_dma_off(drive);
1972 return ide_do_reset(drive);
1973 }
1974 /* Get the number of bytes to transfer on this interrupt. */
1975 bcount.b.high = hwif->INB(IDE_BCOUNTH_REG);
1976 bcount.b.low = hwif->INB(IDE_BCOUNTL_REG);
1977
1978 ireason.all = hwif->INB(IDE_IREASON_REG);
1979
1980 if (ireason.b.cod) {
1981 printk(KERN_ERR "ide-tape: CoD != 0 in idetape_pc_intr\n");
1982 return ide_do_reset(drive);
1983 }
1984 if (ireason.b.io == test_bit(PC_WRITING, &pc->flags)) {
1985 /* Hopefully, we will never get here */
1986 printk(KERN_ERR "ide-tape: We wanted to %s, ",
1987 ireason.b.io ? "Write":"Read");
1988 printk(KERN_ERR "ide-tape: but the tape wants us to %s !\n",
1989 ireason.b.io ? "Read":"Write");
1990 return ide_do_reset(drive);
1991 }
1992 if (!test_bit(PC_WRITING, &pc->flags)) {
1993 /* Reading - Check that we have enough space */
1994 temp = pc->actually_transferred + bcount.all;
1995 if (temp > pc->request_transfer) {
1996 if (temp > pc->buffer_size) {
1997 printk(KERN_ERR "ide-tape: The tape wants to send us more data than expected - discarding data\n");
1998 idetape_discard_data(drive, bcount.all);
1999 ide_set_handler(drive, &idetape_pc_intr, IDETAPE_WAIT_CMD, NULL);
2000 return ide_started;
2001 }
2002#if IDETAPE_DEBUG_LOG
2003 if (tape->debug_level >= 2)
2004 printk(KERN_NOTICE "ide-tape: The tape wants to send us more data than expected - allowing transfer\n");
2005#endif /* IDETAPE_DEBUG_LOG */
2006 }
2007 }
2008 if (test_bit(PC_WRITING, &pc->flags)) {
2009 if (pc->bh != NULL)
2010 idetape_output_buffers(drive, pc, bcount.all);
2011 else
2012 /* Write the current buffer */
2013 HWIF(drive)->atapi_output_bytes(drive, pc->current_position, bcount.all);
2014 } else {
2015 if (pc->bh != NULL)
2016 idetape_input_buffers(drive, pc, bcount.all);
2017 else
2018 /* Read the current buffer */
2019 HWIF(drive)->atapi_input_bytes(drive, pc->current_position, bcount.all);
2020 }
2021 /* Update the current position */
2022 pc->actually_transferred += bcount.all;
2023 pc->current_position += bcount.all;
2024#if IDETAPE_DEBUG_LOG
2025 if (tape->debug_level >= 2)
2026 printk(KERN_INFO "ide-tape: [cmd %x] transferred %d bytes on that interrupt\n", pc->c[0], bcount.all);
2027#endif
2028 /* And set the interrupt handler again */
2029 ide_set_handler(drive, &idetape_pc_intr, IDETAPE_WAIT_CMD, NULL);
2030 return ide_started;
2031}
2032
2033/*
2034 * Packet Command Interface
2035 *
2036 * The current Packet Command is available in tape->pc, and will not
2037 * change until we finish handling it. Each packet command is associated
2038 * with a callback function that will be called when the command is
2039 * finished.
2040 *
2041 * The handling will be done in three stages:
2042 *
2043 * 1. idetape_issue_packet_command will send the packet command to the
2044 * drive, and will set the interrupt handler to idetape_pc_intr.
2045 *
2046 * 2. On each interrupt, idetape_pc_intr will be called. This step
2047 * will be repeated until the device signals us that no more
2048 * interrupts will be issued.
2049 *
2050 * 3. ATAPI Tape media access commands have immediate status with a
2051 * delayed process. In case of a successful initiation of a
2052 * media access packet command, the DSC bit will be set when the
2053 * actual execution of the command is finished.
2054 * Since the tape drive will not issue an interrupt, we have to
2055 * poll for this event. In this case, we define the request as
2056 * "low priority request" by setting rq_status to
2057 * IDETAPE_RQ_POSTPONED, set a timer to poll for DSC and exit
2058 * the driver.
2059 *
2060 * ide.c will then give higher priority to requests which
2061 * originate from the other device, until will change rq_status
2062 * to RQ_ACTIVE.
2063 *
2064 * 4. When the packet command is finished, it will be checked for errors.
2065 *
2066 * 5. In case an error was found, we queue a request sense packet
2067 * command in front of the request queue and retry the operation
2068 * up to IDETAPE_MAX_PC_RETRIES times.
2069 *
2070 * 6. In case no error was found, or we decided to give up and not
2071 * to retry again, the callback function will be called and then
2072 * we will handle the next request.
2073 *
2074 */
2075static ide_startstop_t idetape_transfer_pc(ide_drive_t *drive)
2076{
2077 ide_hwif_t *hwif = drive->hwif;
2078 idetape_tape_t *tape = drive->driver_data;
2079 idetape_pc_t *pc = tape->pc;
2080 atapi_ireason_t ireason;
2081 int retries = 100;
2082 ide_startstop_t startstop;
2083
2084 if (ide_wait_stat(&startstop,drive,DRQ_STAT,BUSY_STAT,WAIT_READY)) {
2085 printk(KERN_ERR "ide-tape: Strange, packet command initiated yet DRQ isn't asserted\n");
2086 return startstop;
2087 }
2088 ireason.all = hwif->INB(IDE_IREASON_REG);
2089 while (retries-- && (!ireason.b.cod || ireason.b.io)) {
2090 printk(KERN_ERR "ide-tape: (IO,CoD != (0,1) while issuing "
2091 "a packet command, retrying\n");
2092 udelay(100);
2093 ireason.all = hwif->INB(IDE_IREASON_REG);
2094 if (retries == 0) {
2095 printk(KERN_ERR "ide-tape: (IO,CoD != (0,1) while "
2096 "issuing a packet command, ignoring\n");
2097 ireason.b.cod = 1;
2098 ireason.b.io = 0;
2099 }
2100 }
2101 if (!ireason.b.cod || ireason.b.io) {
2102 printk(KERN_ERR "ide-tape: (IO,CoD) != (0,1) while issuing "
2103 "a packet command\n");
2104 return ide_do_reset(drive);
2105 }
2106 /* Set the interrupt routine */
2107 ide_set_handler(drive, &idetape_pc_intr, IDETAPE_WAIT_CMD, NULL);
2108#ifdef CONFIG_BLK_DEV_IDEDMA
2109 /* Begin DMA, if necessary */
2110 if (test_bit(PC_DMA_IN_PROGRESS, &pc->flags))
2111 hwif->dma_start(drive);
2112#endif
2113 /* Send the actual packet */
2114 HWIF(drive)->atapi_output_bytes(drive, pc->c, 12);
2115 return ide_started;
2116}
2117
2118static ide_startstop_t idetape_issue_packet_command (ide_drive_t *drive, idetape_pc_t *pc)
2119{
2120 ide_hwif_t *hwif = drive->hwif;
2121 idetape_tape_t *tape = drive->driver_data;
2122 atapi_bcount_t bcount;
2123 int dma_ok = 0;
2124
2125#if IDETAPE_DEBUG_BUGS
2126 if (tape->pc->c[0] == IDETAPE_REQUEST_SENSE_CMD &&
2127 pc->c[0] == IDETAPE_REQUEST_SENSE_CMD) {
2128 printk(KERN_ERR "ide-tape: possible ide-tape.c bug - "
2129 "Two request sense in serial were issued\n");
2130 }
2131#endif /* IDETAPE_DEBUG_BUGS */
2132
2133 if (tape->failed_pc == NULL && pc->c[0] != IDETAPE_REQUEST_SENSE_CMD)
2134 tape->failed_pc = pc;
2135 /* Set the current packet command */
2136 tape->pc = pc;
2137
2138 if (pc->retries > IDETAPE_MAX_PC_RETRIES ||
2139 test_bit(PC_ABORT, &pc->flags)) {
2140 /*
2141 * We will "abort" retrying a packet command in case
2142 * a legitimate error code was received (crossing a
2143 * filemark, or end of the media, for example).
2144 */
2145 if (!test_bit(PC_ABORT, &pc->flags)) {
2146 if (!(pc->c[0] == IDETAPE_TEST_UNIT_READY_CMD &&
2147 tape->sense_key == 2 && tape->asc == 4 &&
2148 (tape->ascq == 1 || tape->ascq == 8))) {
2149 printk(KERN_ERR "ide-tape: %s: I/O error, "
2150 "pc = %2x, key = %2x, "
2151 "asc = %2x, ascq = %2x\n",
2152 tape->name, pc->c[0],
2153 tape->sense_key, tape->asc,
2154 tape->ascq);
2155 }
2156 /* Giving up */
2157 pc->error = IDETAPE_ERROR_GENERAL;
2158 }
2159 tape->failed_pc = NULL;
2160 return pc->callback(drive);
2161 }
2162#if IDETAPE_DEBUG_LOG
2163 if (tape->debug_level >= 2)
2164 printk(KERN_INFO "ide-tape: Retry number - %d, cmd = %02X\n", pc->retries, pc->c[0]);
2165#endif /* IDETAPE_DEBUG_LOG */
2166
2167 pc->retries++;
2168 /* We haven't transferred any data yet */
2169 pc->actually_transferred = 0;
2170 pc->current_position = pc->buffer;
2171 /* Request to transfer the entire buffer at once */
2172 bcount.all = pc->request_transfer;
2173
2174 if (test_and_clear_bit(PC_DMA_ERROR, &pc->flags)) {
2175 printk(KERN_WARNING "ide-tape: DMA disabled, "
2176 "reverting to PIO\n");
2177 (void)__ide_dma_off(drive);
2178 }
2179 if (test_bit(PC_DMA_RECOMMENDED, &pc->flags) && drive->using_dma)
2180 dma_ok = !hwif->dma_setup(drive);
2181
2182 if (IDE_CONTROL_REG)
2183 hwif->OUTB(drive->ctl, IDE_CONTROL_REG);
2184 hwif->OUTB(dma_ok ? 1 : 0, IDE_FEATURE_REG); /* Use PIO/DMA */
2185 hwif->OUTB(bcount.b.high, IDE_BCOUNTH_REG);
2186 hwif->OUTB(bcount.b.low, IDE_BCOUNTL_REG);
2187 hwif->OUTB(drive->select.all, IDE_SELECT_REG);
2188 if (dma_ok) /* Will begin DMA later */
2189 set_bit(PC_DMA_IN_PROGRESS, &pc->flags);
2190 if (test_bit(IDETAPE_DRQ_INTERRUPT, &tape->flags)) {
2191 ide_set_handler(drive, &idetape_transfer_pc, IDETAPE_WAIT_CMD, NULL);
2192 hwif->OUTB(WIN_PACKETCMD, IDE_COMMAND_REG);
2193 return ide_started;
2194 } else {
2195 hwif->OUTB(WIN_PACKETCMD, IDE_COMMAND_REG);
2196 return idetape_transfer_pc(drive);
2197 }
2198}
2199
2200/*
2201 * General packet command callback function.
2202 */
2203static ide_startstop_t idetape_pc_callback (ide_drive_t *drive)
2204{
2205 idetape_tape_t *tape = drive->driver_data;
2206
2207#if IDETAPE_DEBUG_LOG
2208 if (tape->debug_level >= 4)
2209 printk(KERN_INFO "ide-tape: Reached idetape_pc_callback\n");
2210#endif /* IDETAPE_DEBUG_LOG */
2211
2212 idetape_end_request(drive, tape->pc->error ? 0 : 1, 0);
2213 return ide_stopped;
2214}
2215
2216/*
2217 * A mode sense command is used to "sense" tape parameters.
2218 */
2219static void idetape_create_mode_sense_cmd (idetape_pc_t *pc, u8 page_code)
2220{
2221 idetape_init_pc(pc);
2222 pc->c[0] = IDETAPE_MODE_SENSE_CMD;
2223 if (page_code != IDETAPE_BLOCK_DESCRIPTOR)
2224 pc->c[1] = 8; /* DBD = 1 - Don't return block descriptors */
2225 pc->c[2] = page_code;
2226 /*
2227 * Changed pc->c[3] to 0 (255 will at best return unused info).
2228 *
2229 * For SCSI this byte is defined as subpage instead of high byte
2230 * of length and some IDE drives seem to interpret it this way
2231 * and return an error when 255 is used.
2232 */
2233 pc->c[3] = 0;
2234 pc->c[4] = 255; /* (We will just discard data in that case) */
2235 if (page_code == IDETAPE_BLOCK_DESCRIPTOR)
2236 pc->request_transfer = 12;
2237 else if (page_code == IDETAPE_CAPABILITIES_PAGE)
2238 pc->request_transfer = 24;
2239 else
2240 pc->request_transfer = 50;
2241 pc->callback = &idetape_pc_callback;
2242}
2243
2244static void calculate_speeds(ide_drive_t *drive)
2245{
2246 idetape_tape_t *tape = drive->driver_data;
2247 int full = 125, empty = 75;
2248
2249 if (time_after(jiffies, tape->controlled_pipeline_head_time + 120 * HZ)) {
2250 tape->controlled_previous_pipeline_head = tape->controlled_last_pipeline_head;
2251 tape->controlled_previous_head_time = tape->controlled_pipeline_head_time;
2252 tape->controlled_last_pipeline_head = tape->pipeline_head;
2253 tape->controlled_pipeline_head_time = jiffies;
2254 }
2255 if (time_after(jiffies, tape->controlled_pipeline_head_time + 60 * HZ))
2256 tape->controlled_pipeline_head_speed = (tape->pipeline_head - tape->controlled_last_pipeline_head) * 32 * HZ / (jiffies - tape->controlled_pipeline_head_time);
2257 else if (time_after(jiffies, tape->controlled_previous_head_time))
2258 tape->controlled_pipeline_head_speed = (tape->pipeline_head - tape->controlled_previous_pipeline_head) * 32 * HZ / (jiffies - tape->controlled_previous_head_time);
2259
2260 if (tape->nr_pending_stages < tape->max_stages /*- 1 */) {
2261 /* -1 for read mode error recovery */
2262 if (time_after(jiffies, tape->uncontrolled_previous_head_time + 10 * HZ)) {
2263 tape->uncontrolled_pipeline_head_time = jiffies;
2264 tape->uncontrolled_pipeline_head_speed = (tape->pipeline_head - tape->uncontrolled_previous_pipeline_head) * 32 * HZ / (jiffies - tape->uncontrolled_previous_head_time);
2265 }
2266 } else {
2267 tape->uncontrolled_previous_head_time = jiffies;
2268 tape->uncontrolled_previous_pipeline_head = tape->pipeline_head;
2269 if (time_after(jiffies, tape->uncontrolled_pipeline_head_time + 30 * HZ)) {
2270 tape->uncontrolled_pipeline_head_time = jiffies;
2271 }
2272 }
2273 tape->pipeline_head_speed = max(tape->uncontrolled_pipeline_head_speed, tape->controlled_pipeline_head_speed);
2274 if (tape->speed_control == 0) {
2275 tape->max_insert_speed = 5000;
2276 } else if (tape->speed_control == 1) {
2277 if (tape->nr_pending_stages >= tape->max_stages / 2)
2278 tape->max_insert_speed = tape->pipeline_head_speed +
2279 (1100 - tape->pipeline_head_speed) * 2 * (tape->nr_pending_stages - tape->max_stages / 2) / tape->max_stages;
2280 else
2281 tape->max_insert_speed = 500 +
2282 (tape->pipeline_head_speed - 500) * 2 * tape->nr_pending_stages / tape->max_stages;
2283 if (tape->nr_pending_stages >= tape->max_stages * 99 / 100)
2284 tape->max_insert_speed = 5000;
2285 } else if (tape->speed_control == 2) {
2286 tape->max_insert_speed = tape->pipeline_head_speed * empty / 100 +
2287 (tape->pipeline_head_speed * full / 100 - tape->pipeline_head_speed * empty / 100) * tape->nr_pending_stages / tape->max_stages;
2288 } else
2289 tape->max_insert_speed = tape->speed_control;
2290 tape->max_insert_speed = max(tape->max_insert_speed, 500);
2291}
2292
2293static ide_startstop_t idetape_media_access_finished (ide_drive_t *drive)
2294{
2295 idetape_tape_t *tape = drive->driver_data;
2296 idetape_pc_t *pc = tape->pc;
2297 atapi_status_t status;
2298
2299 status.all = HWIF(drive)->INB(IDE_STATUS_REG);
2300 if (status.b.dsc) {
2301 if (status.b.check) {
2302 /* Error detected */
2303 if (pc->c[0] != IDETAPE_TEST_UNIT_READY_CMD)
2304 printk(KERN_ERR "ide-tape: %s: I/O error, ",
2305 tape->name);
2306 /* Retry operation */
2307 return idetape_retry_pc(drive);
2308 }
2309 pc->error = 0;
2310 if (tape->failed_pc == pc)
2311 tape->failed_pc = NULL;
2312 } else {
2313 pc->error = IDETAPE_ERROR_GENERAL;
2314 tape->failed_pc = NULL;
2315 }
2316 return pc->callback(drive);
2317}
2318
2319static ide_startstop_t idetape_rw_callback (ide_drive_t *drive)
2320{
2321 idetape_tape_t *tape = drive->driver_data;
2322 struct request *rq = HWGROUP(drive)->rq;
2323 int blocks = tape->pc->actually_transferred / tape->tape_block_size;
2324
2325 tape->avg_size += blocks * tape->tape_block_size;
2326 tape->insert_size += blocks * tape->tape_block_size;
2327 if (tape->insert_size > 1024 * 1024)
2328 tape->measure_insert_time = 1;
2329 if (tape->measure_insert_time) {
2330 tape->measure_insert_time = 0;
2331 tape->insert_time = jiffies;
2332 tape->insert_size = 0;
2333 }
2334 if (time_after(jiffies, tape->insert_time))
2335 tape->insert_speed = tape->insert_size / 1024 * HZ / (jiffies - tape->insert_time);
2336 if (jiffies - tape->avg_time >= HZ) {
2337 tape->avg_speed = tape->avg_size * HZ / (jiffies - tape->avg_time) / 1024;
2338 tape->avg_size = 0;
2339 tape->avg_time = jiffies;
2340 }
2341
2342#if IDETAPE_DEBUG_LOG
2343 if (tape->debug_level >= 4)
2344 printk(KERN_INFO "ide-tape: Reached idetape_rw_callback\n");
2345#endif /* IDETAPE_DEBUG_LOG */
2346
2347 tape->first_frame_position += blocks;
2348 rq->current_nr_sectors -= blocks;
2349
2350 if (!tape->pc->error)
2351 idetape_end_request(drive, 1, 0);
2352 else
2353 idetape_end_request(drive, tape->pc->error, 0);
2354 return ide_stopped;
2355}
2356
2357static void idetape_create_read_cmd(idetape_tape_t *tape, idetape_pc_t *pc, unsigned int length, struct idetape_bh *bh)
2358{
2359 idetape_init_pc(pc);
2360 pc->c[0] = IDETAPE_READ_CMD;
2361 put_unaligned(htonl(length), (unsigned int *) &pc->c[1]);
2362 pc->c[1] = 1;
2363 pc->callback = &idetape_rw_callback;
2364 pc->bh = bh;
2365 atomic_set(&bh->b_count, 0);
2366 pc->buffer = NULL;
2367 pc->request_transfer = pc->buffer_size = length * tape->tape_block_size;
2368 if (pc->request_transfer == tape->stage_size)
2369 set_bit(PC_DMA_RECOMMENDED, &pc->flags);
2370}
2371
2372static void idetape_create_read_buffer_cmd(idetape_tape_t *tape, idetape_pc_t *pc, unsigned int length, struct idetape_bh *bh)
2373{
2374 int size = 32768;
2375 struct idetape_bh *p = bh;
2376
2377 idetape_init_pc(pc);
2378 pc->c[0] = IDETAPE_READ_BUFFER_CMD;
2379 pc->c[1] = IDETAPE_RETRIEVE_FAULTY_BLOCK;
2380 pc->c[7] = size >> 8;
2381 pc->c[8] = size & 0xff;
2382 pc->callback = &idetape_pc_callback;
2383 pc->bh = bh;
2384 atomic_set(&bh->b_count, 0);
2385 pc->buffer = NULL;
2386 while (p) {
2387 atomic_set(&p->b_count, 0);
2388 p = p->b_reqnext;
2389 }
2390 pc->request_transfer = pc->buffer_size = size;
2391}
2392
2393static void idetape_create_write_cmd(idetape_tape_t *tape, idetape_pc_t *pc, unsigned int length, struct idetape_bh *bh)
2394{
2395 idetape_init_pc(pc);
2396 pc->c[0] = IDETAPE_WRITE_CMD;
2397 put_unaligned(htonl(length), (unsigned int *) &pc->c[1]);
2398 pc->c[1] = 1;
2399 pc->callback = &idetape_rw_callback;
2400 set_bit(PC_WRITING, &pc->flags);
2401 pc->bh = bh;
2402 pc->b_data = bh->b_data;
2403 pc->b_count = atomic_read(&bh->b_count);
2404 pc->buffer = NULL;
2405 pc->request_transfer = pc->buffer_size = length * tape->tape_block_size;
2406 if (pc->request_transfer == tape->stage_size)
2407 set_bit(PC_DMA_RECOMMENDED, &pc->flags);
2408}
2409
2410/*
2411 * idetape_do_request is our request handling function.
2412 */
2413static ide_startstop_t idetape_do_request(ide_drive_t *drive,
2414 struct request *rq, sector_t block)
2415{
2416 idetape_tape_t *tape = drive->driver_data;
2417 idetape_pc_t *pc = NULL;
2418 struct request *postponed_rq = tape->postponed_rq;
2419 atapi_status_t status;
2420
2421#if IDETAPE_DEBUG_LOG
2422#if 0
2423 if (tape->debug_level >= 5)
2424 printk(KERN_INFO "ide-tape: rq_status: %d, "
2425 "dev: %s, cmd: %ld, errors: %d\n", rq->rq_status,
2426 rq->rq_disk->disk_name, rq->cmd[0], rq->errors);
2427#endif
2428 if (tape->debug_level >= 2)
2429 printk(KERN_INFO "ide-tape: sector: %ld, "
2430 "nr_sectors: %ld, current_nr_sectors: %d\n",
2431 rq->sector, rq->nr_sectors, rq->current_nr_sectors);
2432#endif /* IDETAPE_DEBUG_LOG */
2433
2434 if ((rq->flags & REQ_SPECIAL) == 0) {
2435 /*
2436 * We do not support buffer cache originated requests.
2437 */
2438 printk(KERN_NOTICE "ide-tape: %s: Unsupported request in "
2439 "request queue (%ld)\n", drive->name, rq->flags);
2440 ide_end_request(drive, 0, 0);
2441 return ide_stopped;
2442 }
2443
2444 /*
2445 * Retry a failed packet command
2446 */
2447 if (tape->failed_pc != NULL &&
2448 tape->pc->c[0] == IDETAPE_REQUEST_SENSE_CMD) {
2449 return idetape_issue_packet_command(drive, tape->failed_pc);
2450 }
2451#if IDETAPE_DEBUG_BUGS
2452 if (postponed_rq != NULL)
2453 if (rq != postponed_rq) {
2454 printk(KERN_ERR "ide-tape: ide-tape.c bug - "
2455 "Two DSC requests were queued\n");
2456 idetape_end_request(drive, 0, 0);
2457 return ide_stopped;
2458 }
2459#endif /* IDETAPE_DEBUG_BUGS */
2460
2461 tape->postponed_rq = NULL;
2462
2463 /*
2464 * If the tape is still busy, postpone our request and service
2465 * the other device meanwhile.
2466 */
2467 status.all = HWIF(drive)->INB(IDE_STATUS_REG);
2468
2469 if (!drive->dsc_overlap && !(rq->cmd[0] & REQ_IDETAPE_PC2))
2470 set_bit(IDETAPE_IGNORE_DSC, &tape->flags);
2471
2472 if (drive->post_reset == 1) {
2473 set_bit(IDETAPE_IGNORE_DSC, &tape->flags);
2474 drive->post_reset = 0;
2475 }
2476
2477 if (tape->tape_still_time > 100 && tape->tape_still_time < 200)
2478 tape->measure_insert_time = 1;
2479 if (time_after(jiffies, tape->insert_time))
2480 tape->insert_speed = tape->insert_size / 1024 * HZ / (jiffies - tape->insert_time);
2481 calculate_speeds(drive);
2482 if (!test_and_clear_bit(IDETAPE_IGNORE_DSC, &tape->flags) &&
2483 !status.b.dsc) {
2484 if (postponed_rq == NULL) {
2485 tape->dsc_polling_start = jiffies;
2486 tape->dsc_polling_frequency = tape->best_dsc_rw_frequency;
2487 tape->dsc_timeout = jiffies + IDETAPE_DSC_RW_TIMEOUT;
2488 } else if (time_after(jiffies, tape->dsc_timeout)) {
2489 printk(KERN_ERR "ide-tape: %s: DSC timeout\n",
2490 tape->name);
2491 if (rq->cmd[0] & REQ_IDETAPE_PC2) {
2492 idetape_media_access_finished(drive);
2493 return ide_stopped;
2494 } else {
2495 return ide_do_reset(drive);
2496 }
2497 } else if (jiffies - tape->dsc_polling_start > IDETAPE_DSC_MA_THRESHOLD)
2498 tape->dsc_polling_frequency = IDETAPE_DSC_MA_SLOW;
2499 idetape_postpone_request(drive);
2500 return ide_stopped;
2501 }
2502 if (rq->cmd[0] & REQ_IDETAPE_READ) {
2503 tape->buffer_head++;
2504#if USE_IOTRACE
2505 IO_trace(IO_IDETAPE_FIFO, tape->pipeline_head, tape->buffer_head, tape->tape_head, tape->minor);
2506#endif
2507 tape->postpone_cnt = 0;
2508 pc = idetape_next_pc_storage(drive);
2509 idetape_create_read_cmd(tape, pc, rq->current_nr_sectors, (struct idetape_bh *)rq->special);
2510 goto out;
2511 }
2512 if (rq->cmd[0] & REQ_IDETAPE_WRITE) {
2513 tape->buffer_head++;
2514#if USE_IOTRACE
2515 IO_trace(IO_IDETAPE_FIFO, tape->pipeline_head, tape->buffer_head, tape->tape_head, tape->minor);
2516#endif
2517 tape->postpone_cnt = 0;
2518 pc = idetape_next_pc_storage(drive);
2519 idetape_create_write_cmd(tape, pc, rq->current_nr_sectors, (struct idetape_bh *)rq->special);
2520 goto out;
2521 }
2522 if (rq->cmd[0] & REQ_IDETAPE_READ_BUFFER) {
2523 tape->postpone_cnt = 0;
2524 pc = idetape_next_pc_storage(drive);
2525 idetape_create_read_buffer_cmd(tape, pc, rq->current_nr_sectors, (struct idetape_bh *)rq->special);
2526 goto out;
2527 }
2528 if (rq->cmd[0] & REQ_IDETAPE_PC1) {
2529 pc = (idetape_pc_t *) rq->buffer;
2530 rq->cmd[0] &= ~(REQ_IDETAPE_PC1);
2531 rq->cmd[0] |= REQ_IDETAPE_PC2;
2532 goto out;
2533 }
2534 if (rq->cmd[0] & REQ_IDETAPE_PC2) {
2535 idetape_media_access_finished(drive);
2536 return ide_stopped;
2537 }
2538 BUG();
2539out:
2540 return idetape_issue_packet_command(drive, pc);
2541}
2542
2543/*
2544 * Pipeline related functions
2545 */
2546static inline int idetape_pipeline_active (idetape_tape_t *tape)
2547{
2548 int rc1, rc2;
2549
2550 rc1 = test_bit(IDETAPE_PIPELINE_ACTIVE, &tape->flags);
2551 rc2 = (tape->active_data_request != NULL);
2552 return rc1;
2553}
2554
2555/*
2556 * idetape_kmalloc_stage uses __get_free_page to allocate a pipeline
2557 * stage, along with all the necessary small buffers which together make
2558 * a buffer of size tape->stage_size (or a bit more). We attempt to
2559 * combine sequential pages as much as possible.
2560 *
2561 * Returns a pointer to the new allocated stage, or NULL if we
2562 * can't (or don't want to) allocate a stage.
2563 *
2564 * Pipeline stages are optional and are used to increase performance.
2565 * If we can't allocate them, we'll manage without them.
2566 */
2567static idetape_stage_t *__idetape_kmalloc_stage (idetape_tape_t *tape, int full, int clear)
2568{
2569 idetape_stage_t *stage;
2570 struct idetape_bh *prev_bh, *bh;
2571 int pages = tape->pages_per_stage;
2572 char *b_data = NULL;
2573
2574 if ((stage = (idetape_stage_t *) kmalloc (sizeof (idetape_stage_t),GFP_KERNEL)) == NULL)
2575 return NULL;
2576 stage->next = NULL;
2577
2578 bh = stage->bh = (struct idetape_bh *)kmalloc(sizeof(struct idetape_bh), GFP_KERNEL);
2579 if (bh == NULL)
2580 goto abort;
2581 bh->b_reqnext = NULL;
2582 if ((bh->b_data = (char *) __get_free_page (GFP_KERNEL)) == NULL)
2583 goto abort;
2584 if (clear)
2585 memset(bh->b_data, 0, PAGE_SIZE);
2586 bh->b_size = PAGE_SIZE;
2587 atomic_set(&bh->b_count, full ? bh->b_size : 0);
2588
2589 while (--pages) {
2590 if ((b_data = (char *) __get_free_page (GFP_KERNEL)) == NULL)
2591 goto abort;
2592 if (clear)
2593 memset(b_data, 0, PAGE_SIZE);
2594 if (bh->b_data == b_data + PAGE_SIZE) {
2595 bh->b_size += PAGE_SIZE;
2596 bh->b_data -= PAGE_SIZE;
2597 if (full)
2598 atomic_add(PAGE_SIZE, &bh->b_count);
2599 continue;
2600 }
2601 if (b_data == bh->b_data + bh->b_size) {
2602 bh->b_size += PAGE_SIZE;
2603 if (full)
2604 atomic_add(PAGE_SIZE, &bh->b_count);
2605 continue;
2606 }
2607 prev_bh = bh;
2608 if ((bh = (struct idetape_bh *)kmalloc(sizeof(struct idetape_bh), GFP_KERNEL)) == NULL) {
2609 free_page((unsigned long) b_data);
2610 goto abort;
2611 }
2612 bh->b_reqnext = NULL;
2613 bh->b_data = b_data;
2614 bh->b_size = PAGE_SIZE;
2615 atomic_set(&bh->b_count, full ? bh->b_size : 0);
2616 prev_bh->b_reqnext = bh;
2617 }
2618 bh->b_size -= tape->excess_bh_size;
2619 if (full)
2620 atomic_sub(tape->excess_bh_size, &bh->b_count);
2621 return stage;
2622abort:
2623 __idetape_kfree_stage(stage);
2624 return NULL;
2625}
2626
2627static idetape_stage_t *idetape_kmalloc_stage (idetape_tape_t *tape)
2628{
2629 idetape_stage_t *cache_stage = tape->cache_stage;
2630
2631#if IDETAPE_DEBUG_LOG
2632 if (tape->debug_level >= 4)
2633 printk(KERN_INFO "ide-tape: Reached idetape_kmalloc_stage\n");
2634#endif /* IDETAPE_DEBUG_LOG */
2635
2636 if (tape->nr_stages >= tape->max_stages)
2637 return NULL;
2638 if (cache_stage != NULL) {
2639 tape->cache_stage = NULL;
2640 return cache_stage;
2641 }
2642 return __idetape_kmalloc_stage(tape, 0, 0);
2643}
2644
2645static void idetape_copy_stage_from_user (idetape_tape_t *tape, idetape_stage_t *stage, const char __user *buf, int n)
2646{
2647 struct idetape_bh *bh = tape->bh;
2648 int count;
2649
2650 while (n) {
2651#if IDETAPE_DEBUG_BUGS
2652 if (bh == NULL) {
2653 printk(KERN_ERR "ide-tape: bh == NULL in "
2654 "idetape_copy_stage_from_user\n");
2655 return;
2656 }
2657#endif /* IDETAPE_DEBUG_BUGS */
2658 count = min((unsigned int)(bh->b_size - atomic_read(&bh->b_count)), (unsigned int)n);
2659 copy_from_user(bh->b_data + atomic_read(&bh->b_count), buf, count);
2660 n -= count;
2661 atomic_add(count, &bh->b_count);
2662 buf += count;
2663 if (atomic_read(&bh->b_count) == bh->b_size) {
2664 bh = bh->b_reqnext;
2665 if (bh)
2666 atomic_set(&bh->b_count, 0);
2667 }
2668 }
2669 tape->bh = bh;
2670}
2671
2672static void idetape_copy_stage_to_user (idetape_tape_t *tape, char __user *buf, idetape_stage_t *stage, int n)
2673{
2674 struct idetape_bh *bh = tape->bh;
2675 int count;
2676
2677 while (n) {
2678#if IDETAPE_DEBUG_BUGS
2679 if (bh == NULL) {
2680 printk(KERN_ERR "ide-tape: bh == NULL in "
2681 "idetape_copy_stage_to_user\n");
2682 return;
2683 }
2684#endif /* IDETAPE_DEBUG_BUGS */
2685 count = min(tape->b_count, n);
2686 copy_to_user(buf, tape->b_data, count);
2687 n -= count;
2688 tape->b_data += count;
2689 tape->b_count -= count;
2690 buf += count;
2691 if (!tape->b_count) {
2692 tape->bh = bh = bh->b_reqnext;
2693 if (bh) {
2694 tape->b_data = bh->b_data;
2695 tape->b_count = atomic_read(&bh->b_count);
2696 }
2697 }
2698 }
2699}
2700
2701static void idetape_init_merge_stage (idetape_tape_t *tape)
2702{
2703 struct idetape_bh *bh = tape->merge_stage->bh;
2704
2705 tape->bh = bh;
2706 if (tape->chrdev_direction == idetape_direction_write)
2707 atomic_set(&bh->b_count, 0);
2708 else {
2709 tape->b_data = bh->b_data;
2710 tape->b_count = atomic_read(&bh->b_count);
2711 }
2712}
2713
2714static void idetape_switch_buffers (idetape_tape_t *tape, idetape_stage_t *stage)
2715{
2716 struct idetape_bh *tmp;
2717
2718 tmp = stage->bh;
2719 stage->bh = tape->merge_stage->bh;
2720 tape->merge_stage->bh = tmp;
2721 idetape_init_merge_stage(tape);
2722}
2723
2724/*
2725 * idetape_add_stage_tail adds a new stage at the end of the pipeline.
2726 */
2727static void idetape_add_stage_tail (ide_drive_t *drive,idetape_stage_t *stage)
2728{
2729 idetape_tape_t *tape = drive->driver_data;
2730 unsigned long flags;
2731
2732#if IDETAPE_DEBUG_LOG
2733 if (tape->debug_level >= 4)
2734 printk (KERN_INFO "ide-tape: Reached idetape_add_stage_tail\n");
2735#endif /* IDETAPE_DEBUG_LOG */
2736 spin_lock_irqsave(&tape->spinlock, flags);
2737 stage->next = NULL;
2738 if (tape->last_stage != NULL)
2739 tape->last_stage->next=stage;
2740 else
2741 tape->first_stage = tape->next_stage=stage;
2742 tape->last_stage = stage;
2743 if (tape->next_stage == NULL)
2744 tape->next_stage = tape->last_stage;
2745 tape->nr_stages++;
2746 tape->nr_pending_stages++;
2747 spin_unlock_irqrestore(&tape->spinlock, flags);
2748}
2749
2750/*
2751 * idetape_wait_for_request installs a completion in a pending request
2752 * and sleeps until it is serviced.
2753 *
2754 * The caller should ensure that the request will not be serviced
2755 * before we install the completion (usually by disabling interrupts).
2756 */
2757static void idetape_wait_for_request (ide_drive_t *drive, struct request *rq)
2758{
2759 DECLARE_COMPLETION(wait);
2760 idetape_tape_t *tape = drive->driver_data;
2761
2762#if IDETAPE_DEBUG_BUGS
2763 if (rq == NULL || (rq->flags & REQ_SPECIAL) == 0) {
2764 printk (KERN_ERR "ide-tape: bug: Trying to sleep on non-valid request\n");
2765 return;
2766 }
2767#endif /* IDETAPE_DEBUG_BUGS */
2768 rq->waiting = &wait;
2769 rq->end_io = blk_end_sync_rq;
2770 spin_unlock_irq(&tape->spinlock);
2771 wait_for_completion(&wait);
2772 /* The stage and its struct request have been deallocated */
2773 spin_lock_irq(&tape->spinlock);
2774}
2775
2776static ide_startstop_t idetape_read_position_callback (ide_drive_t *drive)
2777{
2778 idetape_tape_t *tape = drive->driver_data;
2779 idetape_read_position_result_t *result;
2780
2781#if IDETAPE_DEBUG_LOG
2782 if (tape->debug_level >= 4)
2783 printk(KERN_INFO "ide-tape: Reached idetape_read_position_callback\n");
2784#endif /* IDETAPE_DEBUG_LOG */
2785
2786 if (!tape->pc->error) {
2787 result = (idetape_read_position_result_t *) tape->pc->buffer;
2788#if IDETAPE_DEBUG_LOG
2789 if (tape->debug_level >= 2)
2790 printk(KERN_INFO "ide-tape: BOP - %s\n",result->bop ? "Yes":"No");
2791 if (tape->debug_level >= 2)
2792 printk(KERN_INFO "ide-tape: EOP - %s\n",result->eop ? "Yes":"No");
2793#endif /* IDETAPE_DEBUG_LOG */
2794 if (result->bpu) {
2795 printk(KERN_INFO "ide-tape: Block location is unknown to the tape\n");
2796 clear_bit(IDETAPE_ADDRESS_VALID, &tape->flags);
2797 idetape_end_request(drive, 0, 0);
2798 } else {
2799#if IDETAPE_DEBUG_LOG
2800 if (tape->debug_level >= 2)
2801 printk(KERN_INFO "ide-tape: Block Location - %u\n", ntohl(result->first_block));
2802#endif /* IDETAPE_DEBUG_LOG */
2803 tape->partition = result->partition;
2804 tape->first_frame_position = ntohl(result->first_block);
2805 tape->last_frame_position = ntohl(result->last_block);
2806 tape->blocks_in_buffer = result->blocks_in_buffer[2];
2807 set_bit(IDETAPE_ADDRESS_VALID, &tape->flags);
2808 idetape_end_request(drive, 1, 0);
2809 }
2810 } else {
2811 idetape_end_request(drive, 0, 0);
2812 }
2813 return ide_stopped;
2814}
2815
2816/*
2817 * idetape_create_write_filemark_cmd will:
2818 *
2819 * 1. Write a filemark if write_filemark=1.
2820 * 2. Flush the device buffers without writing a filemark
2821 * if write_filemark=0.
2822 *
2823 */
2824static void idetape_create_write_filemark_cmd (ide_drive_t *drive, idetape_pc_t *pc,int write_filemark)
2825{
2826 idetape_init_pc(pc);
2827 pc->c[0] = IDETAPE_WRITE_FILEMARK_CMD;
2828 pc->c[4] = write_filemark;
2829 set_bit(PC_WAIT_FOR_DSC, &pc->flags);
2830 pc->callback = &idetape_pc_callback;
2831}
2832
2833static void idetape_create_test_unit_ready_cmd(idetape_pc_t *pc)
2834{
2835 idetape_init_pc(pc);
2836 pc->c[0] = IDETAPE_TEST_UNIT_READY_CMD;
2837 pc->callback = &idetape_pc_callback;
2838}
2839
2840/*
2841 * idetape_queue_pc_tail is based on the following functions:
2842 *
2843 * ide_do_drive_cmd from ide.c
2844 * cdrom_queue_request and cdrom_queue_packet_command from ide-cd.c
2845 *
2846 * We add a special packet command request to the tail of the request
2847 * queue, and wait for it to be serviced.
2848 *
2849 * This is not to be called from within the request handling part
2850 * of the driver ! We allocate here data in the stack, and it is valid
2851 * until the request is finished. This is not the case for the bottom
2852 * part of the driver, where we are always leaving the functions to wait
2853 * for an interrupt or a timer event.
2854 *
2855 * From the bottom part of the driver, we should allocate safe memory
2856 * using idetape_next_pc_storage and idetape_next_rq_storage, and add
2857 * the request to the request list without waiting for it to be serviced !
2858 * In that case, we usually use idetape_queue_pc_head.
2859 */
2860static int __idetape_queue_pc_tail (ide_drive_t *drive, idetape_pc_t *pc)
2861{
2862 struct ide_tape_obj *tape = drive->driver_data;
2863 struct request rq;
2864
2865 idetape_init_rq(&rq, REQ_IDETAPE_PC1);
2866 rq.buffer = (char *) pc;
2867 rq.rq_disk = tape->disk;
2868 return ide_do_drive_cmd(drive, &rq, ide_wait);
2869}
2870
2871static void idetape_create_load_unload_cmd (ide_drive_t *drive, idetape_pc_t *pc,int cmd)
2872{
2873 idetape_init_pc(pc);
2874 pc->c[0] = IDETAPE_LOAD_UNLOAD_CMD;
2875 pc->c[4] = cmd;
2876 set_bit(PC_WAIT_FOR_DSC, &pc->flags);
2877 pc->callback = &idetape_pc_callback;
2878}
2879
2880static int idetape_wait_ready(ide_drive_t *drive, unsigned long timeout)
2881{
2882 idetape_tape_t *tape = drive->driver_data;
2883 idetape_pc_t pc;
2884 int load_attempted = 0;
2885
2886 /*
2887 * Wait for the tape to become ready
2888 */
2889 set_bit(IDETAPE_MEDIUM_PRESENT, &tape->flags);
2890 timeout += jiffies;
2891 while (time_before(jiffies, timeout)) {
2892 idetape_create_test_unit_ready_cmd(&pc);
2893 if (!__idetape_queue_pc_tail(drive, &pc))
2894 return 0;
2895 if ((tape->sense_key == 2 && tape->asc == 4 && tape->ascq == 2)
2896 || (tape->asc == 0x3A)) { /* no media */
2897 if (load_attempted)
2898 return -ENOMEDIUM;
2899 idetape_create_load_unload_cmd(drive, &pc, IDETAPE_LU_LOAD_MASK);
2900 __idetape_queue_pc_tail(drive, &pc);
2901 load_attempted = 1;
2902 /* not about to be ready */
2903 } else if (!(tape->sense_key == 2 && tape->asc == 4 &&
2904 (tape->ascq == 1 || tape->ascq == 8)))
2905 return -EIO;
2906 current->state = TASK_INTERRUPTIBLE;
2907 schedule_timeout(HZ / 10);
2908 }
2909 return -EIO;
2910}
2911
2912static int idetape_queue_pc_tail (ide_drive_t *drive,idetape_pc_t *pc)
2913{
2914 return __idetape_queue_pc_tail(drive, pc);
2915}
2916
2917static int idetape_flush_tape_buffers (ide_drive_t *drive)
2918{
2919 idetape_pc_t pc;
2920 int rc;
2921
2922 idetape_create_write_filemark_cmd(drive, &pc, 0);
2923 if ((rc = idetape_queue_pc_tail(drive, &pc)))
2924 return rc;
2925 idetape_wait_ready(drive, 60 * 5 * HZ);
2926 return 0;
2927}
2928
2929static void idetape_create_read_position_cmd (idetape_pc_t *pc)
2930{
2931 idetape_init_pc(pc);
2932 pc->c[0] = IDETAPE_READ_POSITION_CMD;
2933 pc->request_transfer = 20;
2934 pc->callback = &idetape_read_position_callback;
2935}
2936
2937static int idetape_read_position (ide_drive_t *drive)
2938{
2939 idetape_tape_t *tape = drive->driver_data;
2940 idetape_pc_t pc;
2941 int position;
2942
2943#if IDETAPE_DEBUG_LOG
2944 if (tape->debug_level >= 4)
2945 printk(KERN_INFO "ide-tape: Reached idetape_read_position\n");
2946#endif /* IDETAPE_DEBUG_LOG */
2947
2948 idetape_create_read_position_cmd(&pc);
2949 if (idetape_queue_pc_tail(drive, &pc))
2950 return -1;
2951 position = tape->first_frame_position;
2952 return position;
2953}
2954
2955static void idetape_create_locate_cmd (ide_drive_t *drive, idetape_pc_t *pc, unsigned int block, u8 partition, int skip)
2956{
2957 idetape_init_pc(pc);
2958 pc->c[0] = IDETAPE_LOCATE_CMD;
2959 pc->c[1] = 2;
2960 put_unaligned(htonl(block), (unsigned int *) &pc->c[3]);
2961 pc->c[8] = partition;
2962 set_bit(PC_WAIT_FOR_DSC, &pc->flags);
2963 pc->callback = &idetape_pc_callback;
2964}
2965
2966static int idetape_create_prevent_cmd (ide_drive_t *drive, idetape_pc_t *pc, int prevent)
2967{
2968 idetape_tape_t *tape = drive->driver_data;
2969
2970 if (!tape->capabilities.lock)
2971 return 0;
2972
2973 idetape_init_pc(pc);
2974 pc->c[0] = IDETAPE_PREVENT_CMD;
2975 pc->c[4] = prevent;
2976 pc->callback = &idetape_pc_callback;
2977 return 1;
2978}
2979
2980static int __idetape_discard_read_pipeline (ide_drive_t *drive)
2981{
2982 idetape_tape_t *tape = drive->driver_data;
2983 unsigned long flags;
2984 int cnt;
2985
2986 if (tape->chrdev_direction != idetape_direction_read)
2987 return 0;
2988
2989 /* Remove merge stage. */
2990 cnt = tape->merge_stage_size / tape->tape_block_size;
2991 if (test_and_clear_bit(IDETAPE_FILEMARK, &tape->flags))
2992 ++cnt; /* Filemarks count as 1 sector */
2993 tape->merge_stage_size = 0;
2994 if (tape->merge_stage != NULL) {
2995 __idetape_kfree_stage(tape->merge_stage);
2996 tape->merge_stage = NULL;
2997 }
2998
2999 /* Clear pipeline flags. */
3000 clear_bit(IDETAPE_PIPELINE_ERROR, &tape->flags);
3001 tape->chrdev_direction = idetape_direction_none;
3002
3003 /* Remove pipeline stages. */
3004 if (tape->first_stage == NULL)
3005 return 0;
3006
3007 spin_lock_irqsave(&tape->spinlock, flags);
3008 tape->next_stage = NULL;
3009 if (idetape_pipeline_active(tape))
3010 idetape_wait_for_request(drive, tape->active_data_request);
3011 spin_unlock_irqrestore(&tape->spinlock, flags);
3012
3013 while (tape->first_stage != NULL) {
3014 struct request *rq_ptr = &tape->first_stage->rq;
3015
3016 cnt += rq_ptr->nr_sectors - rq_ptr->current_nr_sectors;
3017 if (rq_ptr->errors == IDETAPE_ERROR_FILEMARK)
3018 ++cnt;
3019 idetape_remove_stage_head(drive);
3020 }
3021 tape->nr_pending_stages = 0;
3022 tape->max_stages = tape->min_pipeline;
3023 return cnt;
3024}
3025
3026/*
3027 * idetape_position_tape positions the tape to the requested block
3028 * using the LOCATE packet command. A READ POSITION command is then
3029 * issued to check where we are positioned.
3030 *
3031 * Like all higher level operations, we queue the commands at the tail
3032 * of the request queue and wait for their completion.
3033 *
3034 */
3035static int idetape_position_tape (ide_drive_t *drive, unsigned int block, u8 partition, int skip)
3036{
3037 idetape_tape_t *tape = drive->driver_data;
3038 int retval;
3039 idetape_pc_t pc;
3040
3041 if (tape->chrdev_direction == idetape_direction_read)
3042 __idetape_discard_read_pipeline(drive);
3043 idetape_wait_ready(drive, 60 * 5 * HZ);
3044 idetape_create_locate_cmd(drive, &pc, block, partition, skip);
3045 retval = idetape_queue_pc_tail(drive, &pc);
3046 if (retval)
3047 return (retval);
3048
3049 idetape_create_read_position_cmd(&pc);
3050 return (idetape_queue_pc_tail(drive, &pc));
3051}
3052
3053static void idetape_discard_read_pipeline (ide_drive_t *drive, int restore_position)
3054{
3055 idetape_tape_t *tape = drive->driver_data;
3056 int cnt;
3057 int seek, position;
3058
3059 cnt = __idetape_discard_read_pipeline(drive);
3060 if (restore_position) {
3061 position = idetape_read_position(drive);
3062 seek = position > cnt ? position - cnt : 0;
3063 if (idetape_position_tape(drive, seek, 0, 0)) {
3064 printk(KERN_INFO "ide-tape: %s: position_tape failed in discard_pipeline()\n", tape->name);
3065 return;
3066 }
3067 }
3068}
3069
3070/*
3071 * idetape_queue_rw_tail generates a read/write request for the block
3072 * device interface and wait for it to be serviced.
3073 */
3074static int idetape_queue_rw_tail(ide_drive_t *drive, int cmd, int blocks, struct idetape_bh *bh)
3075{
3076 idetape_tape_t *tape = drive->driver_data;
3077 struct request rq;
3078
3079#if IDETAPE_DEBUG_LOG
3080 if (tape->debug_level >= 2)
3081 printk(KERN_INFO "ide-tape: idetape_queue_rw_tail: cmd=%d\n",cmd);
3082#endif /* IDETAPE_DEBUG_LOG */
3083#if IDETAPE_DEBUG_BUGS
3084 if (idetape_pipeline_active(tape)) {
3085 printk(KERN_ERR "ide-tape: bug: the pipeline is active in idetape_queue_rw_tail\n");
3086 return (0);
3087 }
3088#endif /* IDETAPE_DEBUG_BUGS */
3089
3090 idetape_init_rq(&rq, cmd);
3091 rq.rq_disk = tape->disk;
3092 rq.special = (void *)bh;
3093 rq.sector = tape->first_frame_position;
3094 rq.nr_sectors = rq.current_nr_sectors = blocks;
3095 (void) ide_do_drive_cmd(drive, &rq, ide_wait);
3096
3097 if ((cmd & (REQ_IDETAPE_READ | REQ_IDETAPE_WRITE)) == 0)
3098 return 0;
3099
3100 if (tape->merge_stage)
3101 idetape_init_merge_stage(tape);
3102 if (rq.errors == IDETAPE_ERROR_GENERAL)
3103 return -EIO;
3104 return (tape->tape_block_size * (blocks-rq.current_nr_sectors));
3105}
3106
3107/*
3108 * idetape_insert_pipeline_into_queue is used to start servicing the
3109 * pipeline stages, starting from tape->next_stage.
3110 */
3111static void idetape_insert_pipeline_into_queue (ide_drive_t *drive)
3112{
3113 idetape_tape_t *tape = drive->driver_data;
3114
3115 if (tape->next_stage == NULL)
3116 return;
3117 if (!idetape_pipeline_active(tape)) {
3118 set_bit(IDETAPE_PIPELINE_ACTIVE, &tape->flags);
3119 idetape_active_next_stage(drive);
3120 (void) ide_do_drive_cmd(drive, tape->active_data_request, ide_end);
3121 }
3122}
3123
3124static void idetape_create_inquiry_cmd (idetape_pc_t *pc)
3125{
3126 idetape_init_pc(pc);
3127 pc->c[0] = IDETAPE_INQUIRY_CMD;
3128 pc->c[4] = pc->request_transfer = 254;
3129 pc->callback = &idetape_pc_callback;
3130}
3131
3132static void idetape_create_rewind_cmd (ide_drive_t *drive, idetape_pc_t *pc)
3133{
3134 idetape_init_pc(pc);
3135 pc->c[0] = IDETAPE_REWIND_CMD;
3136 set_bit(PC_WAIT_FOR_DSC, &pc->flags);
3137 pc->callback = &idetape_pc_callback;
3138}
3139
3140#if 0
3141static void idetape_create_mode_select_cmd (idetape_pc_t *pc, int length)
3142{
3143 idetape_init_pc(pc);
3144 set_bit(PC_WRITING, &pc->flags);
3145 pc->c[0] = IDETAPE_MODE_SELECT_CMD;
3146 pc->c[1] = 0x10;
3147 put_unaligned(htons(length), (unsigned short *) &pc->c[3]);
3148 pc->request_transfer = 255;
3149 pc->callback = &idetape_pc_callback;
3150}
3151#endif
3152
3153static void idetape_create_erase_cmd (idetape_pc_t *pc)
3154{
3155 idetape_init_pc(pc);
3156 pc->c[0] = IDETAPE_ERASE_CMD;
3157 pc->c[1] = 1;
3158 set_bit(PC_WAIT_FOR_DSC, &pc->flags);
3159 pc->callback = &idetape_pc_callback;
3160}
3161
3162static void idetape_create_space_cmd (idetape_pc_t *pc,int count, u8 cmd)
3163{
3164 idetape_init_pc(pc);
3165 pc->c[0] = IDETAPE_SPACE_CMD;
3166 put_unaligned(htonl(count), (unsigned int *) &pc->c[1]);
3167 pc->c[1] = cmd;
3168 set_bit(PC_WAIT_FOR_DSC, &pc->flags);
3169 pc->callback = &idetape_pc_callback;
3170}
3171
3172static void idetape_wait_first_stage (ide_drive_t *drive)
3173{
3174 idetape_tape_t *tape = drive->driver_data;
3175 unsigned long flags;
3176
3177 if (tape->first_stage == NULL)
3178 return;
3179 spin_lock_irqsave(&tape->spinlock, flags);
3180 if (tape->active_stage == tape->first_stage)
3181 idetape_wait_for_request(drive, tape->active_data_request);
3182 spin_unlock_irqrestore(&tape->spinlock, flags);
3183}
3184
3185/*
3186 * idetape_add_chrdev_write_request tries to add a character device
3187 * originated write request to our pipeline. In case we don't succeed,
3188 * we revert to non-pipelined operation mode for this request.
3189 *
3190 * 1. Try to allocate a new pipeline stage.
3191 * 2. If we can't, wait for more and more requests to be serviced
3192 * and try again each time.
3193 * 3. If we still can't allocate a stage, fallback to
3194 * non-pipelined operation mode for this request.
3195 */
3196static int idetape_add_chrdev_write_request (ide_drive_t *drive, int blocks)
3197{
3198 idetape_tape_t *tape = drive->driver_data;
3199 idetape_stage_t *new_stage;
3200 unsigned long flags;
3201 struct request *rq;
3202
3203#if IDETAPE_DEBUG_LOG
3204 if (tape->debug_level >= 3)
3205 printk(KERN_INFO "ide-tape: Reached idetape_add_chrdev_write_request\n");
3206#endif /* IDETAPE_DEBUG_LOG */
3207
3208 /*
3209 * Attempt to allocate a new stage.
3210 * Pay special attention to possible race conditions.
3211 */
3212 while ((new_stage = idetape_kmalloc_stage(tape)) == NULL) {
3213 spin_lock_irqsave(&tape->spinlock, flags);
3214 if (idetape_pipeline_active(tape)) {
3215 idetape_wait_for_request(drive, tape->active_data_request);
3216 spin_unlock_irqrestore(&tape->spinlock, flags);
3217 } else {
3218 spin_unlock_irqrestore(&tape->spinlock, flags);
3219 idetape_insert_pipeline_into_queue(drive);
3220 if (idetape_pipeline_active(tape))
3221 continue;
3222 /*
3223 * Linux is short on memory. Fallback to
3224 * non-pipelined operation mode for this request.
3225 */
3226 return idetape_queue_rw_tail(drive, REQ_IDETAPE_WRITE, blocks, tape->merge_stage->bh);
3227 }
3228 }
3229 rq = &new_stage->rq;
3230 idetape_init_rq(rq, REQ_IDETAPE_WRITE);
3231 /* Doesn't actually matter - We always assume sequential access */
3232 rq->sector = tape->first_frame_position;
3233 rq->nr_sectors = rq->current_nr_sectors = blocks;
3234
3235 idetape_switch_buffers(tape, new_stage);
3236 idetape_add_stage_tail(drive, new_stage);
3237 tape->pipeline_head++;
3238#if USE_IOTRACE
3239 IO_trace(IO_IDETAPE_FIFO, tape->pipeline_head, tape->buffer_head, tape->tape_head, tape->minor);
3240#endif
3241 calculate_speeds(drive);
3242
3243 /*
3244 * Estimate whether the tape has stopped writing by checking
3245 * if our write pipeline is currently empty. If we are not
3246 * writing anymore, wait for the pipeline to be full enough
3247 * (90%) before starting to service requests, so that we will
3248 * be able to keep up with the higher speeds of the tape.
3249 */
3250 if (!idetape_pipeline_active(tape)) {
3251 if (tape->nr_stages >= tape->max_stages * 9 / 10 ||
3252 tape->nr_stages >= tape->max_stages - tape->uncontrolled_pipeline_head_speed * 3 * 1024 / tape->tape_block_size) {
3253 tape->measure_insert_time = 1;
3254 tape->insert_time = jiffies;
3255 tape->insert_size = 0;
3256 tape->insert_speed = 0;
3257 idetape_insert_pipeline_into_queue(drive);
3258 }
3259 }
3260 if (test_and_clear_bit(IDETAPE_PIPELINE_ERROR, &tape->flags))
3261 /* Return a deferred error */
3262 return -EIO;
3263 return blocks;
3264}
3265
3266/*
3267 * idetape_wait_for_pipeline will wait until all pending pipeline
3268 * requests are serviced. Typically called on device close.
3269 */
3270static void idetape_wait_for_pipeline (ide_drive_t *drive)
3271{
3272 idetape_tape_t *tape = drive->driver_data;
3273 unsigned long flags;
3274
3275 while (tape->next_stage || idetape_pipeline_active(tape)) {
3276 idetape_insert_pipeline_into_queue(drive);
3277 spin_lock_irqsave(&tape->spinlock, flags);
3278 if (idetape_pipeline_active(tape))
3279 idetape_wait_for_request(drive, tape->active_data_request);
3280 spin_unlock_irqrestore(&tape->spinlock, flags);
3281 }
3282}
3283
3284static void idetape_empty_write_pipeline (ide_drive_t *drive)
3285{
3286 idetape_tape_t *tape = drive->driver_data;
3287 int blocks, min;
3288 struct idetape_bh *bh;
3289
3290#if IDETAPE_DEBUG_BUGS
3291 if (tape->chrdev_direction != idetape_direction_write) {
3292 printk(KERN_ERR "ide-tape: bug: Trying to empty write pipeline, but we are not writing.\n");
3293 return;
3294 }
3295 if (tape->merge_stage_size > tape->stage_size) {
3296 printk(KERN_ERR "ide-tape: bug: merge_buffer too big\n");
3297 tape->merge_stage_size = tape->stage_size;
3298 }
3299#endif /* IDETAPE_DEBUG_BUGS */
3300 if (tape->merge_stage_size) {
3301 blocks = tape->merge_stage_size / tape->tape_block_size;
3302 if (tape->merge_stage_size % tape->tape_block_size) {
3303 unsigned int i;
3304
3305 blocks++;
3306 i = tape->tape_block_size - tape->merge_stage_size % tape->tape_block_size;
3307 bh = tape->bh->b_reqnext;
3308 while (bh) {
3309 atomic_set(&bh->b_count, 0);
3310 bh = bh->b_reqnext;
3311 }
3312 bh = tape->bh;
3313 while (i) {
3314 if (bh == NULL) {
3315
3316 printk(KERN_INFO "ide-tape: bug, bh NULL\n");
3317 break;
3318 }
3319 min = min(i, (unsigned int)(bh->b_size - atomic_read(&bh->b_count)));
3320 memset(bh->b_data + atomic_read(&bh->b_count), 0, min);
3321 atomic_add(min, &bh->b_count);
3322 i -= min;
3323 bh = bh->b_reqnext;
3324 }
3325 }
3326 (void) idetape_add_chrdev_write_request(drive, blocks);
3327 tape->merge_stage_size = 0;
3328 }
3329 idetape_wait_for_pipeline(drive);
3330 if (tape->merge_stage != NULL) {
3331 __idetape_kfree_stage(tape->merge_stage);
3332 tape->merge_stage = NULL;
3333 }
3334 clear_bit(IDETAPE_PIPELINE_ERROR, &tape->flags);
3335 tape->chrdev_direction = idetape_direction_none;
3336
3337 /*
3338 * On the next backup, perform the feedback loop again.
3339 * (I don't want to keep sense information between backups,
3340 * as some systems are constantly on, and the system load
3341 * can be totally different on the next backup).
3342 */
3343 tape->max_stages = tape->min_pipeline;
3344#if IDETAPE_DEBUG_BUGS
3345 if (tape->first_stage != NULL ||
3346 tape->next_stage != NULL ||
3347 tape->last_stage != NULL ||
3348 tape->nr_stages != 0) {
3349 printk(KERN_ERR "ide-tape: ide-tape pipeline bug, "
3350 "first_stage %p, next_stage %p, "
3351 "last_stage %p, nr_stages %d\n",
3352 tape->first_stage, tape->next_stage,
3353 tape->last_stage, tape->nr_stages);
3354 }
3355#endif /* IDETAPE_DEBUG_BUGS */
3356}
3357
3358static void idetape_restart_speed_control (ide_drive_t *drive)
3359{
3360 idetape_tape_t *tape = drive->driver_data;
3361
3362 tape->restart_speed_control_req = 0;
3363 tape->pipeline_head = 0;
3364 tape->controlled_last_pipeline_head = tape->uncontrolled_last_pipeline_head = 0;
3365 tape->controlled_previous_pipeline_head = tape->uncontrolled_previous_pipeline_head = 0;
3366 tape->pipeline_head_speed = tape->controlled_pipeline_head_speed = 5000;
3367 tape->uncontrolled_pipeline_head_speed = 0;
3368 tape->controlled_pipeline_head_time = tape->uncontrolled_pipeline_head_time = jiffies;
3369 tape->controlled_previous_head_time = tape->uncontrolled_previous_head_time = jiffies;
3370}
3371
3372static int idetape_initiate_read (ide_drive_t *drive, int max_stages)
3373{
3374 idetape_tape_t *tape = drive->driver_data;
3375 idetape_stage_t *new_stage;
3376 struct request rq;
3377 int bytes_read;
3378 int blocks = tape->capabilities.ctl;
3379
3380 /* Initialize read operation */
3381 if (tape->chrdev_direction != idetape_direction_read) {
3382 if (tape->chrdev_direction == idetape_direction_write) {
3383 idetape_empty_write_pipeline(drive);
3384 idetape_flush_tape_buffers(drive);
3385 }
3386#if IDETAPE_DEBUG_BUGS
3387 if (tape->merge_stage || tape->merge_stage_size) {
3388 printk (KERN_ERR "ide-tape: merge_stage_size should be 0 now\n");
3389 tape->merge_stage_size = 0;
3390 }
3391#endif /* IDETAPE_DEBUG_BUGS */
3392 if ((tape->merge_stage = __idetape_kmalloc_stage(tape, 0, 0)) == NULL)
3393 return -ENOMEM;
3394 tape->chrdev_direction = idetape_direction_read;
3395
3396 /*
3397 * Issue a read 0 command to ensure that DSC handshake
3398 * is switched from completion mode to buffer available
3399 * mode.
3400 * No point in issuing this if DSC overlap isn't supported,
3401 * some drives (Seagate STT3401A) will return an error.
3402 */
3403 if (drive->dsc_overlap) {
3404 bytes_read = idetape_queue_rw_tail(drive, REQ_IDETAPE_READ, 0, tape->merge_stage->bh);
3405 if (bytes_read < 0) {
3406 __idetape_kfree_stage(tape->merge_stage);
3407 tape->merge_stage = NULL;
3408 tape->chrdev_direction = idetape_direction_none;
3409 return bytes_read;
3410 }
3411 }
3412 }
3413 if (tape->restart_speed_control_req)
3414 idetape_restart_speed_control(drive);
3415 idetape_init_rq(&rq, REQ_IDETAPE_READ);
3416 rq.sector = tape->first_frame_position;
3417 rq.nr_sectors = rq.current_nr_sectors = blocks;
3418 if (!test_bit(IDETAPE_PIPELINE_ERROR, &tape->flags) &&
3419 tape->nr_stages < max_stages) {
3420 new_stage = idetape_kmalloc_stage(tape);
3421 while (new_stage != NULL) {
3422 new_stage->rq = rq;
3423 idetape_add_stage_tail(drive, new_stage);
3424 if (tape->nr_stages >= max_stages)
3425 break;
3426 new_stage = idetape_kmalloc_stage(tape);
3427 }
3428 }
3429 if (!idetape_pipeline_active(tape)) {
3430 if (tape->nr_pending_stages >= 3 * max_stages / 4) {
3431 tape->measure_insert_time = 1;
3432 tape->insert_time = jiffies;
3433 tape->insert_size = 0;
3434 tape->insert_speed = 0;
3435 idetape_insert_pipeline_into_queue(drive);
3436 }
3437 }
3438 return 0;
3439}
3440
3441/*
3442 * idetape_add_chrdev_read_request is called from idetape_chrdev_read
3443 * to service a character device read request and add read-ahead
3444 * requests to our pipeline.
3445 */
3446static int idetape_add_chrdev_read_request (ide_drive_t *drive,int blocks)
3447{
3448 idetape_tape_t *tape = drive->driver_data;
3449 unsigned long flags;
3450 struct request *rq_ptr;
3451 int bytes_read;
3452
3453#if IDETAPE_DEBUG_LOG
3454 if (tape->debug_level >= 4)
3455 printk(KERN_INFO "ide-tape: Reached idetape_add_chrdev_read_request, %d blocks\n", blocks);
3456#endif /* IDETAPE_DEBUG_LOG */
3457
3458 /*
3459 * If we are at a filemark, return a read length of 0
3460 */
3461 if (test_bit(IDETAPE_FILEMARK, &tape->flags))
3462 return 0;
3463
3464 /*
3465 * Wait for the next block to be available at the head
3466 * of the pipeline
3467 */
3468 idetape_initiate_read(drive, tape->max_stages);
3469 if (tape->first_stage == NULL) {
3470 if (test_bit(IDETAPE_PIPELINE_ERROR, &tape->flags))
3471 return 0;
3472 return idetape_queue_rw_tail(drive, REQ_IDETAPE_READ, blocks, tape->merge_stage->bh);
3473 }
3474 idetape_wait_first_stage(drive);
3475 rq_ptr = &tape->first_stage->rq;
3476 bytes_read = tape->tape_block_size * (rq_ptr->nr_sectors - rq_ptr->current_nr_sectors);
3477 rq_ptr->nr_sectors = rq_ptr->current_nr_sectors = 0;
3478
3479
3480 if (rq_ptr->errors == IDETAPE_ERROR_EOD)
3481 return 0;
3482 else {
3483 idetape_switch_buffers(tape, tape->first_stage);
3484 if (rq_ptr->errors == IDETAPE_ERROR_FILEMARK)
3485 set_bit(IDETAPE_FILEMARK, &tape->flags);
3486 spin_lock_irqsave(&tape->spinlock, flags);
3487 idetape_remove_stage_head(drive);
3488 spin_unlock_irqrestore(&tape->spinlock, flags);
3489 tape->pipeline_head++;
3490#if USE_IOTRACE
3491 IO_trace(IO_IDETAPE_FIFO, tape->pipeline_head, tape->buffer_head, tape->tape_head, tape->minor);
3492#endif
3493 calculate_speeds(drive);
3494 }
3495#if IDETAPE_DEBUG_BUGS
3496 if (bytes_read > blocks * tape->tape_block_size) {
3497 printk(KERN_ERR "ide-tape: bug: trying to return more bytes than requested\n");
3498 bytes_read = blocks * tape->tape_block_size;
3499 }
3500#endif /* IDETAPE_DEBUG_BUGS */
3501 return (bytes_read);
3502}
3503
3504static void idetape_pad_zeros (ide_drive_t *drive, int bcount)
3505{
3506 idetape_tape_t *tape = drive->driver_data;
3507 struct idetape_bh *bh;
3508 int blocks;
3509
3510 while (bcount) {
3511 unsigned int count;
3512
3513 bh = tape->merge_stage->bh;
3514 count = min(tape->stage_size, bcount);
3515 bcount -= count;
3516 blocks = count / tape->tape_block_size;
3517 while (count) {
3518 atomic_set(&bh->b_count, min(count, (unsigned int)bh->b_size));
3519 memset(bh->b_data, 0, atomic_read(&bh->b_count));
3520 count -= atomic_read(&bh->b_count);
3521 bh = bh->b_reqnext;
3522 }
3523 idetape_queue_rw_tail(drive, REQ_IDETAPE_WRITE, blocks, tape->merge_stage->bh);
3524 }
3525}
3526
3527static int idetape_pipeline_size (ide_drive_t *drive)
3528{
3529 idetape_tape_t *tape = drive->driver_data;
3530 idetape_stage_t *stage;
3531 struct request *rq;
3532 int size = 0;
3533
3534 idetape_wait_for_pipeline(drive);
3535 stage = tape->first_stage;
3536 while (stage != NULL) {
3537 rq = &stage->rq;
3538 size += tape->tape_block_size * (rq->nr_sectors-rq->current_nr_sectors);
3539 if (rq->errors == IDETAPE_ERROR_FILEMARK)
3540 size += tape->tape_block_size;
3541 stage = stage->next;
3542 }
3543 size += tape->merge_stage_size;
3544 return size;
3545}
3546
3547/*
3548 * Rewinds the tape to the Beginning Of the current Partition (BOP).
3549 *
3550 * We currently support only one partition.
3551 */
3552static int idetape_rewind_tape (ide_drive_t *drive)
3553{
3554 int retval;
3555 idetape_pc_t pc;
3556#if IDETAPE_DEBUG_LOG
3557 idetape_tape_t *tape = drive->driver_data;
3558 if (tape->debug_level >= 2)
3559 printk(KERN_INFO "ide-tape: Reached idetape_rewind_tape\n");
3560#endif /* IDETAPE_DEBUG_LOG */
3561
3562 idetape_create_rewind_cmd(drive, &pc);
3563 retval = idetape_queue_pc_tail(drive, &pc);
3564 if (retval)
3565 return retval;
3566
3567 idetape_create_read_position_cmd(&pc);
3568 retval = idetape_queue_pc_tail(drive, &pc);
3569 if (retval)
3570 return retval;
3571 return 0;
3572}
3573
3574/*
3575 * Our special ide-tape ioctl's.
3576 *
3577 * Currently there aren't any ioctl's.
3578 * mtio.h compatible commands should be issued to the character device
3579 * interface.
3580 */
3581static int idetape_blkdev_ioctl(ide_drive_t *drive, unsigned int cmd, unsigned long arg)
3582{
3583 idetape_tape_t *tape = drive->driver_data;
3584 idetape_config_t config;
3585 void __user *argp = (void __user *)arg;
3586
3587#if IDETAPE_DEBUG_LOG
3588 if (tape->debug_level >= 4)
3589 printk(KERN_INFO "ide-tape: Reached idetape_blkdev_ioctl\n");
3590#endif /* IDETAPE_DEBUG_LOG */
3591 switch (cmd) {
3592 case 0x0340:
3593 if (copy_from_user(&config, argp, sizeof (idetape_config_t)))
3594 return -EFAULT;
3595 tape->best_dsc_rw_frequency = config.dsc_rw_frequency;
3596 tape->max_stages = config.nr_stages;
3597 break;
3598 case 0x0350:
3599 config.dsc_rw_frequency = (int) tape->best_dsc_rw_frequency;
3600 config.nr_stages = tape->max_stages;
3601 if (copy_to_user(argp, &config, sizeof (idetape_config_t)))
3602 return -EFAULT;
3603 break;
3604 default:
3605 return -EIO;
3606 }
3607 return 0;
3608}
3609
3610/*
3611 * idetape_space_over_filemarks is now a bit more complicated than just
3612 * passing the command to the tape since we may have crossed some
3613 * filemarks during our pipelined read-ahead mode.
3614 *
3615 * As a minor side effect, the pipeline enables us to support MTFSFM when
3616 * the filemark is in our internal pipeline even if the tape doesn't
3617 * support spacing over filemarks in the reverse direction.
3618 */
3619static int idetape_space_over_filemarks (ide_drive_t *drive,short mt_op,int mt_count)
3620{
3621 idetape_tape_t *tape = drive->driver_data;
3622 idetape_pc_t pc;
3623 unsigned long flags;
3624 int retval,count=0;
3625
3626 if (mt_count == 0)
3627 return 0;
3628 if (MTBSF == mt_op || MTBSFM == mt_op) {
3629 if (!tape->capabilities.sprev)
3630 return -EIO;
3631 mt_count = - mt_count;
3632 }
3633
3634 if (tape->chrdev_direction == idetape_direction_read) {
3635 /*
3636 * We have a read-ahead buffer. Scan it for crossed
3637 * filemarks.
3638 */
3639 tape->merge_stage_size = 0;
3640 if (test_and_clear_bit(IDETAPE_FILEMARK, &tape->flags))
3641 ++count;
3642 while (tape->first_stage != NULL) {
3643 if (count == mt_count) {
3644 if (mt_op == MTFSFM)
3645 set_bit(IDETAPE_FILEMARK, &tape->flags);
3646 return 0;
3647 }
3648 spin_lock_irqsave(&tape->spinlock, flags);
3649 if (tape->first_stage == tape->active_stage) {
3650 /*
3651 * We have reached the active stage in the read pipeline.
3652 * There is no point in allowing the drive to continue
3653 * reading any farther, so we stop the pipeline.
3654 *
3655 * This section should be moved to a separate subroutine,
3656 * because a similar function is performed in
3657 * __idetape_discard_read_pipeline(), for example.
3658 */
3659 tape->next_stage = NULL;
3660 spin_unlock_irqrestore(&tape->spinlock, flags);
3661 idetape_wait_first_stage(drive);
3662 tape->next_stage = tape->first_stage->next;
3663 } else
3664 spin_unlock_irqrestore(&tape->spinlock, flags);
3665 if (tape->first_stage->rq.errors == IDETAPE_ERROR_FILEMARK)
3666 ++count;
3667 idetape_remove_stage_head(drive);
3668 }
3669 idetape_discard_read_pipeline(drive, 0);
3670 }
3671
3672 /*
3673 * The filemark was not found in our internal pipeline.
3674 * Now we can issue the space command.
3675 */
3676 switch (mt_op) {
3677 case MTFSF:
3678 case MTBSF:
3679 idetape_create_space_cmd(&pc,mt_count-count,IDETAPE_SPACE_OVER_FILEMARK);
3680 return (idetape_queue_pc_tail(drive, &pc));
3681 case MTFSFM:
3682 case MTBSFM:
3683 if (!tape->capabilities.sprev)
3684 return (-EIO);
3685 retval = idetape_space_over_filemarks(drive, MTFSF, mt_count-count);
3686 if (retval) return (retval);
3687 count = (MTBSFM == mt_op ? 1 : -1);
3688 return (idetape_space_over_filemarks(drive, MTFSF, count));
3689 default:
3690 printk(KERN_ERR "ide-tape: MTIO operation %d not supported\n",mt_op);
3691 return (-EIO);
3692 }
3693}
3694
3695
3696/*
3697 * Our character device read / write functions.
3698 *
3699 * The tape is optimized to maximize throughput when it is transferring
3700 * an integral number of the "continuous transfer limit", which is
3701 * a parameter of the specific tape (26 KB on my particular tape).
3702 * (32 kB for Onstream)
3703 *
3704 * As of version 1.3 of the driver, the character device provides an
3705 * abstract continuous view of the media - any mix of block sizes (even 1
3706 * byte) on the same backup/restore procedure is supported. The driver
3707 * will internally convert the requests to the recommended transfer unit,
3708 * so that an unmatch between the user's block size to the recommended
3709 * size will only result in a (slightly) increased driver overhead, but
3710 * will no longer hit performance.
3711 * This is not applicable to Onstream.
3712 */
3713static ssize_t idetape_chrdev_read (struct file *file, char __user *buf,
3714 size_t count, loff_t *ppos)
3715{
3716 struct ide_tape_obj *tape = ide_tape_f(file);
3717 ide_drive_t *drive = tape->drive;
3718 ssize_t bytes_read,temp, actually_read = 0, rc;
3719
3720#if IDETAPE_DEBUG_LOG
3721 if (tape->debug_level >= 3)
3722 printk(KERN_INFO "ide-tape: Reached idetape_chrdev_read, count %Zd\n", count);
3723#endif /* IDETAPE_DEBUG_LOG */
3724
3725 if (tape->chrdev_direction != idetape_direction_read) {
3726 if (test_bit(IDETAPE_DETECT_BS, &tape->flags))
3727 if (count > tape->tape_block_size &&
3728 (count % tape->tape_block_size) == 0)
3729 tape->user_bs_factor = count / tape->tape_block_size;
3730 }
3731 if ((rc = idetape_initiate_read(drive, tape->max_stages)) < 0)
3732 return rc;
3733 if (count == 0)
3734 return (0);
3735 if (tape->merge_stage_size) {
3736 actually_read = min((unsigned int)(tape->merge_stage_size), (unsigned int)count);
3737 idetape_copy_stage_to_user(tape, buf, tape->merge_stage, actually_read);
3738 buf += actually_read;
3739 tape->merge_stage_size -= actually_read;
3740 count -= actually_read;
3741 }
3742 while (count >= tape->stage_size) {
3743 bytes_read = idetape_add_chrdev_read_request(drive, tape->capabilities.ctl);
3744 if (bytes_read <= 0)
3745 goto finish;
3746 idetape_copy_stage_to_user(tape, buf, tape->merge_stage, bytes_read);
3747 buf += bytes_read;
3748 count -= bytes_read;
3749 actually_read += bytes_read;
3750 }
3751 if (count) {
3752 bytes_read = idetape_add_chrdev_read_request(drive, tape->capabilities.ctl);
3753 if (bytes_read <= 0)
3754 goto finish;
3755 temp = min((unsigned long)count, (unsigned long)bytes_read);
3756 idetape_copy_stage_to_user(tape, buf, tape->merge_stage, temp);
3757 actually_read += temp;
3758 tape->merge_stage_size = bytes_read-temp;
3759 }
3760finish:
3761 if (!actually_read && test_bit(IDETAPE_FILEMARK, &tape->flags)) {
3762#if IDETAPE_DEBUG_LOG
3763 if (tape->debug_level >= 2)
3764 printk(KERN_INFO "ide-tape: %s: spacing over filemark\n", tape->name);
3765#endif
3766 idetape_space_over_filemarks(drive, MTFSF, 1);
3767 return 0;
3768 }
3769 return actually_read;
3770}
3771
3772static ssize_t idetape_chrdev_write (struct file *file, const char __user *buf,
3773 size_t count, loff_t *ppos)
3774{
3775 struct ide_tape_obj *tape = ide_tape_f(file);
3776 ide_drive_t *drive = tape->drive;
3777 ssize_t retval, actually_written = 0;
3778
3779 /* The drive is write protected. */
3780 if (tape->write_prot)
3781 return -EACCES;
3782
3783#if IDETAPE_DEBUG_LOG
3784 if (tape->debug_level >= 3)
3785 printk(KERN_INFO "ide-tape: Reached idetape_chrdev_write, "
3786 "count %Zd\n", count);
3787#endif /* IDETAPE_DEBUG_LOG */
3788
3789 /* Initialize write operation */
3790 if (tape->chrdev_direction != idetape_direction_write) {
3791 if (tape->chrdev_direction == idetape_direction_read)
3792 idetape_discard_read_pipeline(drive, 1);
3793#if IDETAPE_DEBUG_BUGS
3794 if (tape->merge_stage || tape->merge_stage_size) {
3795 printk(KERN_ERR "ide-tape: merge_stage_size "
3796 "should be 0 now\n");
3797 tape->merge_stage_size = 0;
3798 }
3799#endif /* IDETAPE_DEBUG_BUGS */
3800 if ((tape->merge_stage = __idetape_kmalloc_stage(tape, 0, 0)) == NULL)
3801 return -ENOMEM;
3802 tape->chrdev_direction = idetape_direction_write;
3803 idetape_init_merge_stage(tape);
3804
3805 /*
3806 * Issue a write 0 command to ensure that DSC handshake
3807 * is switched from completion mode to buffer available
3808 * mode.
3809 * No point in issuing this if DSC overlap isn't supported,
3810 * some drives (Seagate STT3401A) will return an error.
3811 */
3812 if (drive->dsc_overlap) {
3813 retval = idetape_queue_rw_tail(drive, REQ_IDETAPE_WRITE, 0, tape->merge_stage->bh);
3814 if (retval < 0) {
3815 __idetape_kfree_stage(tape->merge_stage);
3816 tape->merge_stage = NULL;
3817 tape->chrdev_direction = idetape_direction_none;
3818 return retval;
3819 }
3820 }
3821 }
3822 if (count == 0)
3823 return (0);
3824 if (tape->restart_speed_control_req)
3825 idetape_restart_speed_control(drive);
3826 if (tape->merge_stage_size) {
3827#if IDETAPE_DEBUG_BUGS
3828 if (tape->merge_stage_size >= tape->stage_size) {
3829 printk(KERN_ERR "ide-tape: bug: merge buffer too big\n");
3830 tape->merge_stage_size = 0;
3831 }
3832#endif /* IDETAPE_DEBUG_BUGS */
3833 actually_written = min((unsigned int)(tape->stage_size - tape->merge_stage_size), (unsigned int)count);
3834 idetape_copy_stage_from_user(tape, tape->merge_stage, buf, actually_written);
3835 buf += actually_written;
3836 tape->merge_stage_size += actually_written;
3837 count -= actually_written;
3838
3839 if (tape->merge_stage_size == tape->stage_size) {
3840 tape->merge_stage_size = 0;
3841 retval = idetape_add_chrdev_write_request(drive, tape->capabilities.ctl);
3842 if (retval <= 0)
3843 return (retval);
3844 }
3845 }
3846 while (count >= tape->stage_size) {
3847 idetape_copy_stage_from_user(tape, tape->merge_stage, buf, tape->stage_size);
3848 buf += tape->stage_size;
3849 count -= tape->stage_size;
3850 retval = idetape_add_chrdev_write_request(drive, tape->capabilities.ctl);
3851 actually_written += tape->stage_size;
3852 if (retval <= 0)
3853 return (retval);
3854 }
3855 if (count) {
3856 actually_written += count;
3857 idetape_copy_stage_from_user(tape, tape->merge_stage, buf, count);
3858 tape->merge_stage_size += count;
3859 }
3860 return (actually_written);
3861}
3862
3863static int idetape_write_filemark (ide_drive_t *drive)
3864{
3865 idetape_pc_t pc;
3866
3867 /* Write a filemark */
3868 idetape_create_write_filemark_cmd(drive, &pc, 1);
3869 if (idetape_queue_pc_tail(drive, &pc)) {
3870 printk(KERN_ERR "ide-tape: Couldn't write a filemark\n");
3871 return -EIO;
3872 }
3873 return 0;
3874}
3875
3876/*
3877 * idetape_mtioctop is called from idetape_chrdev_ioctl when
3878 * the general mtio MTIOCTOP ioctl is requested.
3879 *
3880 * We currently support the following mtio.h operations:
3881 *
3882 * MTFSF - Space over mt_count filemarks in the positive direction.
3883 * The tape is positioned after the last spaced filemark.
3884 *
3885 * MTFSFM - Same as MTFSF, but the tape is positioned before the
3886 * last filemark.
3887 *
3888 * MTBSF - Steps background over mt_count filemarks, tape is
3889 * positioned before the last filemark.
3890 *
3891 * MTBSFM - Like MTBSF, only tape is positioned after the last filemark.
3892 *
3893 * Note:
3894 *
3895 * MTBSF and MTBSFM are not supported when the tape doesn't
3896 * support spacing over filemarks in the reverse direction.
3897 * In this case, MTFSFM is also usually not supported (it is
3898 * supported in the rare case in which we crossed the filemark
3899 * during our read-ahead pipelined operation mode).
3900 *
3901 * MTWEOF - Writes mt_count filemarks. Tape is positioned after
3902 * the last written filemark.
3903 *
3904 * MTREW - Rewinds tape.
3905 *
3906 * MTLOAD - Loads the tape.
3907 *
3908 * MTOFFL - Puts the tape drive "Offline": Rewinds the tape and
3909 * MTUNLOAD prevents further access until the media is replaced.
3910 *
3911 * MTNOP - Flushes tape buffers.
3912 *
3913 * MTRETEN - Retension media. This typically consists of one end
3914 * to end pass on the media.
3915 *
3916 * MTEOM - Moves to the end of recorded data.
3917 *
3918 * MTERASE - Erases tape.
3919 *
3920 * MTSETBLK - Sets the user block size to mt_count bytes. If
3921 * mt_count is 0, we will attempt to autodetect
3922 * the block size.
3923 *
3924 * MTSEEK - Positions the tape in a specific block number, where
3925 * each block is assumed to contain which user_block_size
3926 * bytes.
3927 *
3928 * MTSETPART - Switches to another tape partition.
3929 *
3930 * MTLOCK - Locks the tape door.
3931 *
3932 * MTUNLOCK - Unlocks the tape door.
3933 *
3934 * The following commands are currently not supported:
3935 *
3936 * MTFSS, MTBSS, MTWSM, MTSETDENSITY,
3937 * MTSETDRVBUFFER, MT_ST_BOOLEANS, MT_ST_WRITE_THRESHOLD.
3938 */
3939static int idetape_mtioctop (ide_drive_t *drive,short mt_op,int mt_count)
3940{
3941 idetape_tape_t *tape = drive->driver_data;
3942 idetape_pc_t pc;
3943 int i,retval;
3944
3945#if IDETAPE_DEBUG_LOG
3946 if (tape->debug_level >= 1)
3947 printk(KERN_INFO "ide-tape: Handling MTIOCTOP ioctl: "
3948 "mt_op=%d, mt_count=%d\n", mt_op, mt_count);
3949#endif /* IDETAPE_DEBUG_LOG */
3950 /*
3951 * Commands which need our pipelined read-ahead stages.
3952 */
3953 switch (mt_op) {
3954 case MTFSF:
3955 case MTFSFM:
3956 case MTBSF:
3957 case MTBSFM:
3958 if (!mt_count)
3959 return (0);
3960 return (idetape_space_over_filemarks(drive,mt_op,mt_count));
3961 default:
3962 break;
3963 }
3964 switch (mt_op) {
3965 case MTWEOF:
3966 if (tape->write_prot)
3967 return -EACCES;
3968 idetape_discard_read_pipeline(drive, 1);
3969 for (i = 0; i < mt_count; i++) {
3970 retval = idetape_write_filemark(drive);
3971 if (retval)
3972 return retval;
3973 }
3974 return (0);
3975 case MTREW:
3976 idetape_discard_read_pipeline(drive, 0);
3977 if (idetape_rewind_tape(drive))
3978 return -EIO;
3979 return 0;
3980 case MTLOAD:
3981 idetape_discard_read_pipeline(drive, 0);
3982 idetape_create_load_unload_cmd(drive, &pc, IDETAPE_LU_LOAD_MASK);
3983 return (idetape_queue_pc_tail(drive, &pc));
3984 case MTUNLOAD:
3985 case MTOFFL:
3986 /*
3987 * If door is locked, attempt to unlock before
3988 * attempting to eject.
3989 */
3990 if (tape->door_locked) {
3991 if (idetape_create_prevent_cmd(drive, &pc, 0))
3992 if (!idetape_queue_pc_tail(drive, &pc))
3993 tape->door_locked = DOOR_UNLOCKED;
3994 }
3995 idetape_discard_read_pipeline(drive, 0);
3996 idetape_create_load_unload_cmd(drive, &pc,!IDETAPE_LU_LOAD_MASK);
3997 retval = idetape_queue_pc_tail(drive, &pc);
3998 if (!retval)
3999 clear_bit(IDETAPE_MEDIUM_PRESENT, &tape->flags);
4000 return retval;
4001 case MTNOP:
4002 idetape_discard_read_pipeline(drive, 0);
4003 return (idetape_flush_tape_buffers(drive));
4004 case MTRETEN:
4005 idetape_discard_read_pipeline(drive, 0);
4006 idetape_create_load_unload_cmd(drive, &pc,IDETAPE_LU_RETENSION_MASK | IDETAPE_LU_LOAD_MASK);
4007 return (idetape_queue_pc_tail(drive, &pc));
4008 case MTEOM:
4009 idetape_create_space_cmd(&pc, 0, IDETAPE_SPACE_TO_EOD);
4010 return (idetape_queue_pc_tail(drive, &pc));
4011 case MTERASE:
4012 (void) idetape_rewind_tape(drive);
4013 idetape_create_erase_cmd(&pc);
4014 return (idetape_queue_pc_tail(drive, &pc));
4015 case MTSETBLK:
4016 if (mt_count) {
4017 if (mt_count < tape->tape_block_size || mt_count % tape->tape_block_size)
4018 return -EIO;
4019 tape->user_bs_factor = mt_count / tape->tape_block_size;
4020 clear_bit(IDETAPE_DETECT_BS, &tape->flags);
4021 } else
4022 set_bit(IDETAPE_DETECT_BS, &tape->flags);
4023 return 0;
4024 case MTSEEK:
4025 idetape_discard_read_pipeline(drive, 0);
4026 return idetape_position_tape(drive, mt_count * tape->user_bs_factor, tape->partition, 0);
4027 case MTSETPART:
4028 idetape_discard_read_pipeline(drive, 0);
4029 return (idetape_position_tape(drive, 0, mt_count, 0));
4030 case MTFSR:
4031 case MTBSR:
4032 case MTLOCK:
4033 if (!idetape_create_prevent_cmd(drive, &pc, 1))
4034 return 0;
4035 retval = idetape_queue_pc_tail(drive, &pc);
4036 if (retval) return retval;
4037 tape->door_locked = DOOR_EXPLICITLY_LOCKED;
4038 return 0;
4039 case MTUNLOCK:
4040 if (!idetape_create_prevent_cmd(drive, &pc, 0))
4041 return 0;
4042 retval = idetape_queue_pc_tail(drive, &pc);
4043 if (retval) return retval;
4044 tape->door_locked = DOOR_UNLOCKED;
4045 return 0;
4046 default:
4047 printk(KERN_ERR "ide-tape: MTIO operation %d not "
4048 "supported\n", mt_op);
4049 return (-EIO);
4050 }
4051}
4052
4053/*
4054 * Our character device ioctls.
4055 *
4056 * General mtio.h magnetic io commands are supported here, and not in
4057 * the corresponding block interface.
4058 *
4059 * The following ioctls are supported:
4060 *
4061 * MTIOCTOP - Refer to idetape_mtioctop for detailed description.
4062 *
4063 * MTIOCGET - The mt_dsreg field in the returned mtget structure
4064 * will be set to (user block size in bytes <<
4065 * MT_ST_BLKSIZE_SHIFT) & MT_ST_BLKSIZE_MASK.
4066 *
4067 * The mt_blkno is set to the current user block number.
4068 * The other mtget fields are not supported.
4069 *
4070 * MTIOCPOS - The current tape "block position" is returned. We
4071 * assume that each block contains user_block_size
4072 * bytes.
4073 *
4074 * Our own ide-tape ioctls are supported on both interfaces.
4075 */
4076static int idetape_chrdev_ioctl (struct inode *inode, struct file *file, unsigned int cmd, unsigned long arg)
4077{
4078 struct ide_tape_obj *tape = ide_tape_f(file);
4079 ide_drive_t *drive = tape->drive;
4080 struct mtop mtop;
4081 struct mtget mtget;
4082 struct mtpos mtpos;
4083 int block_offset = 0, position = tape->first_frame_position;
4084 void __user *argp = (void __user *)arg;
4085
4086#if IDETAPE_DEBUG_LOG
4087 if (tape->debug_level >= 3)
4088 printk(KERN_INFO "ide-tape: Reached idetape_chrdev_ioctl, "
4089 "cmd=%u\n", cmd);
4090#endif /* IDETAPE_DEBUG_LOG */
4091
4092 tape->restart_speed_control_req = 1;
4093 if (tape->chrdev_direction == idetape_direction_write) {
4094 idetape_empty_write_pipeline(drive);
4095 idetape_flush_tape_buffers(drive);
4096 }
4097 if (cmd == MTIOCGET || cmd == MTIOCPOS) {
4098 block_offset = idetape_pipeline_size(drive) / (tape->tape_block_size * tape->user_bs_factor);
4099 if ((position = idetape_read_position(drive)) < 0)
4100 return -EIO;
4101 }
4102 switch (cmd) {
4103 case MTIOCTOP:
4104 if (copy_from_user(&mtop, argp, sizeof (struct mtop)))
4105 return -EFAULT;
4106 return (idetape_mtioctop(drive,mtop.mt_op,mtop.mt_count));
4107 case MTIOCGET:
4108 memset(&mtget, 0, sizeof (struct mtget));
4109 mtget.mt_type = MT_ISSCSI2;
4110 mtget.mt_blkno = position / tape->user_bs_factor - block_offset;
4111 mtget.mt_dsreg = ((tape->tape_block_size * tape->user_bs_factor) << MT_ST_BLKSIZE_SHIFT) & MT_ST_BLKSIZE_MASK;
4112 if (tape->drv_write_prot) {
4113 mtget.mt_gstat |= GMT_WR_PROT(0xffffffff);
4114 }
4115 if (copy_to_user(argp, &mtget, sizeof(struct mtget)))
4116 return -EFAULT;
4117 return 0;
4118 case MTIOCPOS:
4119 mtpos.mt_blkno = position / tape->user_bs_factor - block_offset;
4120 if (copy_to_user(argp, &mtpos, sizeof(struct mtpos)))
4121 return -EFAULT;
4122 return 0;
4123 default:
4124 if (tape->chrdev_direction == idetape_direction_read)
4125 idetape_discard_read_pipeline(drive, 1);
4126 return idetape_blkdev_ioctl(drive, cmd, arg);
4127 }
4128}
4129
4130static void idetape_get_blocksize_from_block_descriptor(ide_drive_t *drive);
4131
4132/*
4133 * Our character device open function.
4134 */
4135static int idetape_chrdev_open (struct inode *inode, struct file *filp)
4136{
4137 unsigned int minor = iminor(inode), i = minor & ~0xc0;
4138 ide_drive_t *drive;
4139 idetape_tape_t *tape;
4140 idetape_pc_t pc;
4141 int retval;
4142
4143 /*
4144 * We really want to do nonseekable_open(inode, filp); here, but some
4145 * versions of tar incorrectly call lseek on tapes and bail out if that
4146 * fails. So we disallow pread() and pwrite(), but permit lseeks.
4147 */
4148 filp->f_mode &= ~(FMODE_PREAD | FMODE_PWRITE);
4149
4150#if IDETAPE_DEBUG_LOG
4151 printk(KERN_INFO "ide-tape: Reached idetape_chrdev_open\n");
4152#endif /* IDETAPE_DEBUG_LOG */
4153
4154 if (i >= MAX_HWIFS * MAX_DRIVES)
4155 return -ENXIO;
4156
4157 if (!(tape = ide_tape_chrdev_get(i)))
4158 return -ENXIO;
4159
4160 drive = tape->drive;
4161
4162 filp->private_data = tape;
4163
4164 if (test_and_set_bit(IDETAPE_BUSY, &tape->flags)) {
4165 retval = -EBUSY;
4166 goto out_put_tape;
4167 }
4168
4169 retval = idetape_wait_ready(drive, 60 * HZ);
4170 if (retval) {
4171 clear_bit(IDETAPE_BUSY, &tape->flags);
4172 printk(KERN_ERR "ide-tape: %s: drive not ready\n", tape->name);
4173 goto out_put_tape;
4174 }
4175
4176 idetape_read_position(drive);
4177 if (!test_bit(IDETAPE_ADDRESS_VALID, &tape->flags))
4178 (void)idetape_rewind_tape(drive);
4179
4180 if (tape->chrdev_direction != idetape_direction_read)
4181 clear_bit(IDETAPE_PIPELINE_ERROR, &tape->flags);
4182
4183 /* Read block size and write protect status from drive. */
4184 idetape_get_blocksize_from_block_descriptor(drive);
4185
4186 /* Set write protect flag if device is opened as read-only. */
4187 if ((filp->f_flags & O_ACCMODE) == O_RDONLY)
4188 tape->write_prot = 1;
4189 else
4190 tape->write_prot = tape->drv_write_prot;
4191
4192 /* Make sure drive isn't write protected if user wants to write. */
4193 if (tape->write_prot) {
4194 if ((filp->f_flags & O_ACCMODE) == O_WRONLY ||
4195 (filp->f_flags & O_ACCMODE) == O_RDWR) {
4196 clear_bit(IDETAPE_BUSY, &tape->flags);
4197 retval = -EROFS;
4198 goto out_put_tape;
4199 }
4200 }
4201
4202 /*
4203 * Lock the tape drive door so user can't eject.
4204 */
4205 if (tape->chrdev_direction == idetape_direction_none) {
4206 if (idetape_create_prevent_cmd(drive, &pc, 1)) {
4207 if (!idetape_queue_pc_tail(drive, &pc)) {
4208 if (tape->door_locked != DOOR_EXPLICITLY_LOCKED)
4209 tape->door_locked = DOOR_LOCKED;
4210 }
4211 }
4212 }
4213 idetape_restart_speed_control(drive);
4214 tape->restart_speed_control_req = 0;
4215 return 0;
4216
4217out_put_tape:
4218 ide_tape_put(tape);
4219 return retval;
4220}
4221
4222static void idetape_write_release (ide_drive_t *drive, unsigned int minor)
4223{
4224 idetape_tape_t *tape = drive->driver_data;
4225
4226 idetape_empty_write_pipeline(drive);
4227 tape->merge_stage = __idetape_kmalloc_stage(tape, 1, 0);
4228 if (tape->merge_stage != NULL) {
4229 idetape_pad_zeros(drive, tape->tape_block_size * (tape->user_bs_factor - 1));
4230 __idetape_kfree_stage(tape->merge_stage);
4231 tape->merge_stage = NULL;
4232 }
4233 idetape_write_filemark(drive);
4234 idetape_flush_tape_buffers(drive);
4235 idetape_flush_tape_buffers(drive);
4236}
4237
4238/*
4239 * Our character device release function.
4240 */
4241static int idetape_chrdev_release (struct inode *inode, struct file *filp)
4242{
4243 struct ide_tape_obj *tape = ide_tape_f(filp);
4244 ide_drive_t *drive = tape->drive;
4245 idetape_pc_t pc;
4246 unsigned int minor = iminor(inode);
4247
4248 lock_kernel();
4249 tape = drive->driver_data;
4250#if IDETAPE_DEBUG_LOG
4251 if (tape->debug_level >= 3)
4252 printk(KERN_INFO "ide-tape: Reached idetape_chrdev_release\n");
4253#endif /* IDETAPE_DEBUG_LOG */
4254
4255 if (tape->chrdev_direction == idetape_direction_write)
4256 idetape_write_release(drive, minor);
4257 if (tape->chrdev_direction == idetape_direction_read) {
4258 if (minor < 128)
4259 idetape_discard_read_pipeline(drive, 1);
4260 else
4261 idetape_wait_for_pipeline(drive);
4262 }
4263 if (tape->cache_stage != NULL) {
4264 __idetape_kfree_stage(tape->cache_stage);
4265 tape->cache_stage = NULL;
4266 }
4267 if (minor < 128 && test_bit(IDETAPE_MEDIUM_PRESENT, &tape->flags))
4268 (void) idetape_rewind_tape(drive);
4269 if (tape->chrdev_direction == idetape_direction_none) {
4270 if (tape->door_locked == DOOR_LOCKED) {
4271 if (idetape_create_prevent_cmd(drive, &pc, 0)) {
4272 if (!idetape_queue_pc_tail(drive, &pc))
4273 tape->door_locked = DOOR_UNLOCKED;
4274 }
4275 }
4276 }
4277 clear_bit(IDETAPE_BUSY, &tape->flags);
4278 ide_tape_put(tape);
4279 unlock_kernel();
4280 return 0;
4281}
4282
4283/*
4284 * idetape_identify_device is called to check the contents of the
4285 * ATAPI IDENTIFY command results. We return:
4286 *
4287 * 1 If the tape can be supported by us, based on the information
4288 * we have so far.
4289 *
4290 * 0 If this tape driver is not currently supported by us.
4291 */
4292static int idetape_identify_device (ide_drive_t *drive)
4293{
4294 struct idetape_id_gcw gcw;
4295 struct hd_driveid *id = drive->id;
4296#if IDETAPE_DEBUG_INFO
4297 unsigned short mask,i;
4298#endif /* IDETAPE_DEBUG_INFO */
4299
4300 if (drive->id_read == 0)
4301 return 1;
4302
4303 *((unsigned short *) &gcw) = id->config;
4304
4305#if IDETAPE_DEBUG_INFO
4306 printk(KERN_INFO "ide-tape: Dumping ATAPI Identify Device tape parameters\n");
4307 printk(KERN_INFO "ide-tape: Protocol Type: ");
4308 switch (gcw.protocol) {
4309 case 0: case 1: printk("ATA\n");break;
4310 case 2: printk("ATAPI\n");break;
4311 case 3: printk("Reserved (Unknown to ide-tape)\n");break;
4312 }
4313 printk(KERN_INFO "ide-tape: Device Type: %x - ",gcw.device_type);
4314 switch (gcw.device_type) {
4315 case 0: printk("Direct-access Device\n");break;
4316 case 1: printk("Streaming Tape Device\n");break;
4317 case 2: case 3: case 4: printk("Reserved\n");break;
4318 case 5: printk("CD-ROM Device\n");break;
4319 case 6: printk("Reserved\n");
4320 case 7: printk("Optical memory Device\n");break;
4321 case 0x1f: printk("Unknown or no Device type\n");break;
4322 default: printk("Reserved\n");
4323 }
4324 printk(KERN_INFO "ide-tape: Removable: %s",gcw.removable ? "Yes\n":"No\n");
4325 printk(KERN_INFO "ide-tape: Command Packet DRQ Type: ");
4326 switch (gcw.drq_type) {
4327 case 0: printk("Microprocessor DRQ\n");break;
4328 case 1: printk("Interrupt DRQ\n");break;
4329 case 2: printk("Accelerated DRQ\n");break;
4330 case 3: printk("Reserved\n");break;
4331 }
4332 printk(KERN_INFO "ide-tape: Command Packet Size: ");
4333 switch (gcw.packet_size) {
4334 case 0: printk("12 bytes\n");break;
4335 case 1: printk("16 bytes\n");break;
4336 default: printk("Reserved\n");break;
4337 }
4338 printk(KERN_INFO "ide-tape: Model: %.40s\n",id->model);
4339 printk(KERN_INFO "ide-tape: Firmware Revision: %.8s\n",id->fw_rev);
4340 printk(KERN_INFO "ide-tape: Serial Number: %.20s\n",id->serial_no);
4341 printk(KERN_INFO "ide-tape: Write buffer size: %d bytes\n",id->buf_size*512);
4342 printk(KERN_INFO "ide-tape: DMA: %s",id->capability & 0x01 ? "Yes\n":"No\n");
4343 printk(KERN_INFO "ide-tape: LBA: %s",id->capability & 0x02 ? "Yes\n":"No\n");
4344 printk(KERN_INFO "ide-tape: IORDY can be disabled: %s",id->capability & 0x04 ? "Yes\n":"No\n");
4345 printk(KERN_INFO "ide-tape: IORDY supported: %s",id->capability & 0x08 ? "Yes\n":"Unknown\n");
4346 printk(KERN_INFO "ide-tape: ATAPI overlap supported: %s",id->capability & 0x20 ? "Yes\n":"No\n");
4347 printk(KERN_INFO "ide-tape: PIO Cycle Timing Category: %d\n",id->tPIO);
4348 printk(KERN_INFO "ide-tape: DMA Cycle Timing Category: %d\n",id->tDMA);
4349 printk(KERN_INFO "ide-tape: Single Word DMA supported modes: ");
4350 for (i=0,mask=1;i<8;i++,mask=mask << 1) {
4351 if (id->dma_1word & mask)
4352 printk("%d ",i);
4353 if (id->dma_1word & (mask << 8))
4354 printk("(active) ");
4355 }
4356 printk("\n");
4357 printk(KERN_INFO "ide-tape: Multi Word DMA supported modes: ");
4358 for (i=0,mask=1;i<8;i++,mask=mask << 1) {
4359 if (id->dma_mword & mask)
4360 printk("%d ",i);
4361 if (id->dma_mword & (mask << 8))
4362 printk("(active) ");
4363 }
4364 printk("\n");
4365 if (id->field_valid & 0x0002) {
4366 printk(KERN_INFO "ide-tape: Enhanced PIO Modes: %s\n",
4367 id->eide_pio_modes & 1 ? "Mode 3":"None");
4368 printk(KERN_INFO "ide-tape: Minimum Multi-word DMA cycle per word: ");
4369 if (id->eide_dma_min == 0)
4370 printk("Not supported\n");
4371 else
4372 printk("%d ns\n",id->eide_dma_min);
4373
4374 printk(KERN_INFO "ide-tape: Manufacturer\'s Recommended Multi-word cycle: ");
4375 if (id->eide_dma_time == 0)
4376 printk("Not supported\n");
4377 else
4378 printk("%d ns\n",id->eide_dma_time);
4379
4380 printk(KERN_INFO "ide-tape: Minimum PIO cycle without IORDY: ");
4381 if (id->eide_pio == 0)
4382 printk("Not supported\n");
4383 else
4384 printk("%d ns\n",id->eide_pio);
4385
4386 printk(KERN_INFO "ide-tape: Minimum PIO cycle with IORDY: ");
4387 if (id->eide_pio_iordy == 0)
4388 printk("Not supported\n");
4389 else
4390 printk("%d ns\n",id->eide_pio_iordy);
4391
4392 } else
4393 printk(KERN_INFO "ide-tape: According to the device, fields 64-70 are not valid.\n");
4394#endif /* IDETAPE_DEBUG_INFO */
4395
4396 /* Check that we can support this device */
4397
4398 if (gcw.protocol !=2 )
4399 printk(KERN_ERR "ide-tape: Protocol is not ATAPI\n");
4400 else if (gcw.device_type != 1)
4401 printk(KERN_ERR "ide-tape: Device type is not set to tape\n");
4402 else if (!gcw.removable)
4403 printk(KERN_ERR "ide-tape: The removable flag is not set\n");
4404 else if (gcw.packet_size != 0) {
4405 printk(KERN_ERR "ide-tape: Packet size is not 12 bytes long\n");
4406 if (gcw.packet_size == 1)
4407 printk(KERN_ERR "ide-tape: Sorry, padding to 16 bytes is still not supported\n");
4408 } else
4409 return 1;
4410 return 0;
4411}
4412
4413/*
4414 * Use INQUIRY to get the firmware revision
4415 */
4416static void idetape_get_inquiry_results (ide_drive_t *drive)
4417{
4418 char *r;
4419 idetape_tape_t *tape = drive->driver_data;
4420 idetape_pc_t pc;
4421 idetape_inquiry_result_t *inquiry;
4422
4423 idetape_create_inquiry_cmd(&pc);
4424 if (idetape_queue_pc_tail(drive, &pc)) {
4425 printk(KERN_ERR "ide-tape: %s: can't get INQUIRY results\n", tape->name);
4426 return;
4427 }
4428 inquiry = (idetape_inquiry_result_t *) pc.buffer;
4429 memcpy(tape->vendor_id, inquiry->vendor_id, 8);
4430 memcpy(tape->product_id, inquiry->product_id, 16);
4431 memcpy(tape->firmware_revision, inquiry->revision_level, 4);
4432 ide_fixstring(tape->vendor_id, 10, 0);
4433 ide_fixstring(tape->product_id, 18, 0);
4434 ide_fixstring(tape->firmware_revision, 6, 0);
4435 r = tape->firmware_revision;
4436 if (*(r + 1) == '.')
4437 tape->firmware_revision_num = (*r - '0') * 100 + (*(r + 2) - '0') * 10 + *(r + 3) - '0';
4438 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);
4439}
4440
4441/*
4442 * idetape_get_mode_sense_results asks the tape about its various
4443 * parameters. In particular, we will adjust our data transfer buffer
4444 * size to the recommended value as returned by the tape.
4445 */
4446static void idetape_get_mode_sense_results (ide_drive_t *drive)
4447{
4448 idetape_tape_t *tape = drive->driver_data;
4449 idetape_pc_t pc;
4450 idetape_mode_parameter_header_t *header;
4451 idetape_capabilities_page_t *capabilities;
4452
4453 idetape_create_mode_sense_cmd(&pc, IDETAPE_CAPABILITIES_PAGE);
4454 if (idetape_queue_pc_tail(drive, &pc)) {
4455 printk(KERN_ERR "ide-tape: Can't get tape parameters - assuming some default values\n");
4456 tape->tape_block_size = 512;
4457 tape->capabilities.ctl = 52;
4458 tape->capabilities.speed = 450;
4459 tape->capabilities.buffer_size = 6 * 52;
4460 return;
4461 }
4462 header = (idetape_mode_parameter_header_t *) pc.buffer;
4463 capabilities = (idetape_capabilities_page_t *) (pc.buffer + sizeof(idetape_mode_parameter_header_t) + header->bdl);
4464
4465 capabilities->max_speed = ntohs(capabilities->max_speed);
4466 capabilities->ctl = ntohs(capabilities->ctl);
4467 capabilities->speed = ntohs(capabilities->speed);
4468 capabilities->buffer_size = ntohs(capabilities->buffer_size);
4469
4470 if (!capabilities->speed) {
4471 printk(KERN_INFO "ide-tape: %s: overriding capabilities->speed (assuming 650KB/sec)\n", drive->name);
4472 capabilities->speed = 650;
4473 }
4474 if (!capabilities->max_speed) {
4475 printk(KERN_INFO "ide-tape: %s: overriding capabilities->max_speed (assuming 650KB/sec)\n", drive->name);
4476 capabilities->max_speed = 650;
4477 }
4478
4479 tape->capabilities = *capabilities; /* Save us a copy */
4480 if (capabilities->blk512)
4481 tape->tape_block_size = 512;
4482 else if (capabilities->blk1024)
4483 tape->tape_block_size = 1024;
4484
4485#if IDETAPE_DEBUG_INFO
4486 printk(KERN_INFO "ide-tape: Dumping the results of the MODE SENSE packet command\n");
4487 printk(KERN_INFO "ide-tape: Mode Parameter Header:\n");
4488 printk(KERN_INFO "ide-tape: Mode Data Length - %d\n",header->mode_data_length);
4489 printk(KERN_INFO "ide-tape: Medium Type - %d\n",header->medium_type);
4490 printk(KERN_INFO "ide-tape: Device Specific Parameter - %d\n",header->dsp);
4491 printk(KERN_INFO "ide-tape: Block Descriptor Length - %d\n",header->bdl);
4492
4493 printk(KERN_INFO "ide-tape: Capabilities and Mechanical Status Page:\n");
4494 printk(KERN_INFO "ide-tape: Page code - %d\n",capabilities->page_code);
4495 printk(KERN_INFO "ide-tape: Page length - %d\n",capabilities->page_length);
4496 printk(KERN_INFO "ide-tape: Read only - %s\n",capabilities->ro ? "Yes":"No");
4497 printk(KERN_INFO "ide-tape: Supports reverse space - %s\n",capabilities->sprev ? "Yes":"No");
4498 printk(KERN_INFO "ide-tape: Supports erase initiated formatting - %s\n",capabilities->efmt ? "Yes":"No");
4499 printk(KERN_INFO "ide-tape: Supports QFA two Partition format - %s\n",capabilities->qfa ? "Yes":"No");
4500 printk(KERN_INFO "ide-tape: Supports locking the medium - %s\n",capabilities->lock ? "Yes":"No");
4501 printk(KERN_INFO "ide-tape: The volume is currently locked - %s\n",capabilities->locked ? "Yes":"No");
4502 printk(KERN_INFO "ide-tape: The device defaults in the prevent state - %s\n",capabilities->prevent ? "Yes":"No");
4503 printk(KERN_INFO "ide-tape: Supports ejecting the medium - %s\n",capabilities->eject ? "Yes":"No");
4504 printk(KERN_INFO "ide-tape: Supports error correction - %s\n",capabilities->ecc ? "Yes":"No");
4505 printk(KERN_INFO "ide-tape: Supports data compression - %s\n",capabilities->cmprs ? "Yes":"No");
4506 printk(KERN_INFO "ide-tape: Supports 512 bytes block size - %s\n",capabilities->blk512 ? "Yes":"No");
4507 printk(KERN_INFO "ide-tape: Supports 1024 bytes block size - %s\n",capabilities->blk1024 ? "Yes":"No");
4508 printk(KERN_INFO "ide-tape: Supports 32768 bytes block size / Restricted byte count for PIO transfers - %s\n",capabilities->blk32768 ? "Yes":"No");
4509 printk(KERN_INFO "ide-tape: Maximum supported speed in KBps - %d\n",capabilities->max_speed);
4510 printk(KERN_INFO "ide-tape: Continuous transfer limits in blocks - %d\n",capabilities->ctl);
4511 printk(KERN_INFO "ide-tape: Current speed in KBps - %d\n",capabilities->speed);
4512 printk(KERN_INFO "ide-tape: Buffer size - %d\n",capabilities->buffer_size*512);
4513#endif /* IDETAPE_DEBUG_INFO */
4514}
4515
4516/*
4517 * ide_get_blocksize_from_block_descriptor does a mode sense page 0 with block descriptor
4518 * and if it succeeds sets the tape block size with the reported value
4519 */
4520static void idetape_get_blocksize_from_block_descriptor(ide_drive_t *drive)
4521{
4522
4523 idetape_tape_t *tape = drive->driver_data;
4524 idetape_pc_t pc;
4525 idetape_mode_parameter_header_t *header;
4526 idetape_parameter_block_descriptor_t *block_descrp;
4527
4528 idetape_create_mode_sense_cmd(&pc, IDETAPE_BLOCK_DESCRIPTOR);
4529 if (idetape_queue_pc_tail(drive, &pc)) {
4530 printk(KERN_ERR "ide-tape: Can't get block descriptor\n");
4531 if (tape->tape_block_size == 0) {
4532 printk(KERN_WARNING "ide-tape: Cannot deal with zero block size, assume 32k\n");
4533 tape->tape_block_size = 32768;
4534 }
4535 return;
4536 }
4537 header = (idetape_mode_parameter_header_t *) pc.buffer;
4538 block_descrp = (idetape_parameter_block_descriptor_t *) (pc.buffer + sizeof(idetape_mode_parameter_header_t));
4539 tape->tape_block_size =( block_descrp->length[0]<<16) + (block_descrp->length[1]<<8) + block_descrp->length[2];
4540 tape->drv_write_prot = (header->dsp & 0x80) >> 7;
4541
4542#if IDETAPE_DEBUG_INFO
4543 printk(KERN_INFO "ide-tape: Adjusted block size - %d\n", tape->tape_block_size);
4544#endif /* IDETAPE_DEBUG_INFO */
4545}
4546static void idetape_add_settings (ide_drive_t *drive)
4547{
4548 idetape_tape_t *tape = drive->driver_data;
4549
4550/*
4551 * drive setting name read/write ioctl ioctl data type min max mul_factor div_factor data pointer set function
4552 */
4553 ide_add_setting(drive, "buffer", SETTING_READ, -1, -1, TYPE_SHORT, 0, 0xffff, 1, 2, &tape->capabilities.buffer_size, NULL);
4554 ide_add_setting(drive, "pipeline_min", SETTING_RW, -1, -1, TYPE_INT, 1, 0xffff, tape->stage_size / 1024, 1, &tape->min_pipeline, NULL);
4555 ide_add_setting(drive, "pipeline", SETTING_RW, -1, -1, TYPE_INT, 1, 0xffff, tape->stage_size / 1024, 1, &tape->max_stages, NULL);
4556 ide_add_setting(drive, "pipeline_max", SETTING_RW, -1, -1, TYPE_INT, 1, 0xffff, tape->stage_size / 1024, 1, &tape->max_pipeline, NULL);
4557 ide_add_setting(drive, "pipeline_used",SETTING_READ, -1, -1, TYPE_INT, 0, 0xffff, tape->stage_size / 1024, 1, &tape->nr_stages, NULL);
4558 ide_add_setting(drive, "pipeline_pending",SETTING_READ,-1, -1, TYPE_INT, 0, 0xffff, tape->stage_size / 1024, 1, &tape->nr_pending_stages, NULL);
4559 ide_add_setting(drive, "speed", SETTING_READ, -1, -1, TYPE_SHORT, 0, 0xffff, 1, 1, &tape->capabilities.speed, NULL);
4560 ide_add_setting(drive, "stage", SETTING_READ, -1, -1, TYPE_INT, 0, 0xffff, 1, 1024, &tape->stage_size, NULL);
4561 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);
4562 ide_add_setting(drive, "dsc_overlap", SETTING_RW, -1, -1, TYPE_BYTE, 0, 1, 1, 1, &drive->dsc_overlap, NULL);
4563 ide_add_setting(drive, "pipeline_head_speed_c",SETTING_READ, -1, -1, TYPE_INT, 0, 0xffff, 1, 1, &tape->controlled_pipeline_head_speed, NULL);
4564 ide_add_setting(drive, "pipeline_head_speed_u",SETTING_READ, -1, -1, TYPE_INT, 0, 0xffff, 1, 1, &tape->uncontrolled_pipeline_head_speed, NULL);
4565 ide_add_setting(drive, "avg_speed", SETTING_READ, -1, -1, TYPE_INT, 0, 0xffff, 1, 1, &tape->avg_speed, NULL);
4566 ide_add_setting(drive, "debug_level",SETTING_RW, -1, -1, TYPE_INT, 0, 0xffff, 1, 1, &tape->debug_level, NULL);
4567}
4568
4569/*
4570 * ide_setup is called to:
4571 *
4572 * 1. Initialize our various state variables.
4573 * 2. Ask the tape for its capabilities.
4574 * 3. Allocate a buffer which will be used for data
4575 * transfer. The buffer size is chosen based on
4576 * the recommendation which we received in step (2).
4577 *
4578 * Note that at this point ide.c already assigned us an irq, so that
4579 * we can queue requests here and wait for their completion.
4580 */
4581static void idetape_setup (ide_drive_t *drive, idetape_tape_t *tape, int minor)
4582{
4583 unsigned long t1, tmid, tn, t;
4584 int speed;
4585 struct idetape_id_gcw gcw;
4586 int stage_size;
4587 struct sysinfo si;
4588
4589 spin_lock_init(&tape->spinlock);
4590 drive->dsc_overlap = 1;
4591#ifdef CONFIG_BLK_DEV_IDEPCI
4592 if (HWIF(drive)->pci_dev != NULL) {
4593 /*
4594 * These two ide-pci host adapters appear to need DSC overlap disabled.
4595 * This probably needs further analysis.
4596 */
4597 if ((HWIF(drive)->pci_dev->device == PCI_DEVICE_ID_ARTOP_ATP850UF) ||
4598 (HWIF(drive)->pci_dev->device == PCI_DEVICE_ID_TTI_HPT343)) {
4599 printk(KERN_INFO "ide-tape: %s: disabling DSC overlap\n", tape->name);
4600 drive->dsc_overlap = 0;
4601 }
4602 }
4603#endif /* CONFIG_BLK_DEV_IDEPCI */
4604 /* Seagate Travan drives do not support DSC overlap. */
4605 if (strstr(drive->id->model, "Seagate STT3401"))
4606 drive->dsc_overlap = 0;
4607 tape->minor = minor;
4608 tape->name[0] = 'h';
4609 tape->name[1] = 't';
4610 tape->name[2] = '0' + minor;
4611 tape->chrdev_direction = idetape_direction_none;
4612 tape->pc = tape->pc_stack;
4613 tape->max_insert_speed = 10000;
4614 tape->speed_control = 1;
4615 *((unsigned short *) &gcw) = drive->id->config;
4616 if (gcw.drq_type == 1)
4617 set_bit(IDETAPE_DRQ_INTERRUPT, &tape->flags);
4618
4619 tape->min_pipeline = tape->max_pipeline = tape->max_stages = 10;
4620
4621 idetape_get_inquiry_results(drive);
4622 idetape_get_mode_sense_results(drive);
4623 idetape_get_blocksize_from_block_descriptor(drive);
4624 tape->user_bs_factor = 1;
4625 tape->stage_size = tape->capabilities.ctl * tape->tape_block_size;
4626 while (tape->stage_size > 0xffff) {
4627 printk(KERN_NOTICE "ide-tape: decreasing stage size\n");
4628 tape->capabilities.ctl /= 2;
4629 tape->stage_size = tape->capabilities.ctl * tape->tape_block_size;
4630 }
4631 stage_size = tape->stage_size;
4632 tape->pages_per_stage = stage_size / PAGE_SIZE;
4633 if (stage_size % PAGE_SIZE) {
4634 tape->pages_per_stage++;
4635 tape->excess_bh_size = PAGE_SIZE - stage_size % PAGE_SIZE;
4636 }
4637
4638 /*
4639 * Select the "best" DSC read/write polling frequency
4640 * and pipeline size.
4641 */
4642 speed = max(tape->capabilities.speed, tape->capabilities.max_speed);
4643
4644 tape->max_stages = speed * 1000 * 10 / tape->stage_size;
4645
4646 /*
4647 * Limit memory use for pipeline to 10% of physical memory
4648 */
4649 si_meminfo(&si);
4650 if (tape->max_stages * tape->stage_size > si.totalram * si.mem_unit / 10)
4651 tape->max_stages = si.totalram * si.mem_unit / (10 * tape->stage_size);
4652 tape->max_stages = min(tape->max_stages, IDETAPE_MAX_PIPELINE_STAGES);
4653 tape->min_pipeline = min(tape->max_stages, IDETAPE_MIN_PIPELINE_STAGES);
4654 tape->max_pipeline = min(tape->max_stages * 2, IDETAPE_MAX_PIPELINE_STAGES);
4655 if (tape->max_stages == 0)
4656 tape->max_stages = tape->min_pipeline = tape->max_pipeline = 1;
4657
4658 t1 = (tape->stage_size * HZ) / (speed * 1000);
4659 tmid = (tape->capabilities.buffer_size * 32 * HZ) / (speed * 125);
4660 tn = (IDETAPE_FIFO_THRESHOLD * tape->stage_size * HZ) / (speed * 1000);
4661
4662 if (tape->max_stages)
4663 t = tn;
4664 else
4665 t = t1;
4666
4667 /*
4668 * Ensure that the number we got makes sense; limit
4669 * it within IDETAPE_DSC_RW_MIN and IDETAPE_DSC_RW_MAX.
4670 */
4671 tape->best_dsc_rw_frequency = max_t(unsigned long, min_t(unsigned long, t, IDETAPE_DSC_RW_MAX), IDETAPE_DSC_RW_MIN);
4672 printk(KERN_INFO "ide-tape: %s <-> %s: %dKBps, %d*%dkB buffer, "
4673 "%dkB pipeline, %lums tDSC%s\n",
4674 drive->name, tape->name, tape->capabilities.speed,
4675 (tape->capabilities.buffer_size * 512) / tape->stage_size,
4676 tape->stage_size / 1024,
4677 tape->max_stages * tape->stage_size / 1024,
4678 tape->best_dsc_rw_frequency * 1000 / HZ,
4679 drive->using_dma ? ", DMA":"");
4680
4681 idetape_add_settings(drive);
4682}
4683
4684static int idetape_cleanup (ide_drive_t *drive)
4685{
4686 idetape_tape_t *tape = drive->driver_data;
4687 unsigned long flags;
4688
4689 spin_lock_irqsave(&ide_lock, flags);
4690 if (test_bit(IDETAPE_BUSY, &tape->flags) || drive->usage ||
4691 tape->first_stage != NULL || tape->merge_stage_size) {
4692 spin_unlock_irqrestore(&ide_lock, flags);
4693 return 1;
4694 }
4695
4696 spin_unlock_irqrestore(&ide_lock, flags);
4697 DRIVER(drive)->busy = 0;
4698 (void) ide_unregister_subdriver(drive);
4699
4700 ide_unregister_region(tape->disk);
4701
4702 ide_tape_put(tape);
4703
4704 return 0;
4705}
4706
4707static void ide_tape_release(struct kref *kref)
4708{
4709 struct ide_tape_obj *tape = to_ide_tape(kref);
4710 ide_drive_t *drive = tape->drive;
4711 struct gendisk *g = tape->disk;
4712
4713 drive->dsc_overlap = 0;
4714 drive->driver_data = NULL;
4715 devfs_remove("%s/mt", drive->devfs_name);
4716 devfs_remove("%s/mtn", drive->devfs_name);
4717 devfs_unregister_tape(g->number);
4718 idetape_devs[tape->minor] = NULL;
4719 g->private_data = NULL;
4720 put_disk(g);
4721 kfree(tape);
4722}
4723
4724#ifdef CONFIG_PROC_FS
4725
4726static int proc_idetape_read_name
4727 (char *page, char **start, off_t off, int count, int *eof, void *data)
4728{
4729 ide_drive_t *drive = (ide_drive_t *) data;
4730 idetape_tape_t *tape = drive->driver_data;
4731 char *out = page;
4732 int len;
4733
4734 len = sprintf(out, "%s\n", tape->name);
4735 PROC_IDE_READ_RETURN(page, start, off, count, eof, len);
4736}
4737
4738static ide_proc_entry_t idetape_proc[] = {
4739 { "capacity", S_IFREG|S_IRUGO, proc_ide_read_capacity, NULL },
4740 { "name", S_IFREG|S_IRUGO, proc_idetape_read_name, NULL },
4741 { NULL, 0, NULL, NULL }
4742};
4743
4744#else
4745
4746#define idetape_proc NULL
4747
4748#endif
4749
4750static int idetape_attach(ide_drive_t *drive);
4751
4752/*
4753 * IDE subdriver functions, registered with ide.c
4754 */
4755static ide_driver_t idetape_driver = {
4756 .owner = THIS_MODULE,
4757 .name = "ide-tape",
4758 .version = IDETAPE_VERSION,
4759 .media = ide_tape,
4760 .busy = 1,
4761 .supports_dsc_overlap = 1,
4762 .cleanup = idetape_cleanup,
4763 .do_request = idetape_do_request,
4764 .end_request = idetape_end_request,
4765 .error = __ide_error,
4766 .abort = __ide_abort,
4767 .proc = idetape_proc,
4768 .attach = idetape_attach,
4769 .drives = LIST_HEAD_INIT(idetape_driver.drives),
4770};
4771
4772/*
4773 * Our character device supporting functions, passed to register_chrdev.
4774 */
4775static struct file_operations idetape_fops = {
4776 .owner = THIS_MODULE,
4777 .read = idetape_chrdev_read,
4778 .write = idetape_chrdev_write,
4779 .ioctl = idetape_chrdev_ioctl,
4780 .open = idetape_chrdev_open,
4781 .release = idetape_chrdev_release,
4782};
4783
4784static int idetape_open(struct inode *inode, struct file *filp)
4785{
4786 struct gendisk *disk = inode->i_bdev->bd_disk;
4787 struct ide_tape_obj *tape;
4788 ide_drive_t *drive;
4789
4790 if (!(tape = ide_tape_get(disk)))
4791 return -ENXIO;
4792
4793 drive = tape->drive;
4794
4795 drive->usage++;
4796
4797 return 0;
4798}
4799
4800static int idetape_release(struct inode *inode, struct file *filp)
4801{
4802 struct gendisk *disk = inode->i_bdev->bd_disk;
4803 struct ide_tape_obj *tape = ide_tape_g(disk);
4804 ide_drive_t *drive = tape->drive;
4805
4806 drive->usage--;
4807
4808 ide_tape_put(tape);
4809
4810 return 0;
4811}
4812
4813static int idetape_ioctl(struct inode *inode, struct file *file,
4814 unsigned int cmd, unsigned long arg)
4815{
4816 struct block_device *bdev = inode->i_bdev;
4817 struct ide_tape_obj *tape = ide_tape_g(bdev->bd_disk);
4818 ide_drive_t *drive = tape->drive;
4819 int err = generic_ide_ioctl(drive, file, bdev, cmd, arg);
4820 if (err == -EINVAL)
4821 err = idetape_blkdev_ioctl(drive, cmd, arg);
4822 return err;
4823}
4824
4825static struct block_device_operations idetape_block_ops = {
4826 .owner = THIS_MODULE,
4827 .open = idetape_open,
4828 .release = idetape_release,
4829 .ioctl = idetape_ioctl,
4830};
4831
4832static int idetape_attach (ide_drive_t *drive)
4833{
4834 idetape_tape_t *tape;
4835 struct gendisk *g;
4836 int minor;
4837
4838 if (!strstr("ide-tape", drive->driver_req))
4839 goto failed;
4840 if (!drive->present)
4841 goto failed;
4842 if (drive->media != ide_tape)
4843 goto failed;
4844 if (!idetape_identify_device (drive)) {
4845 printk(KERN_ERR "ide-tape: %s: not supported by this version of ide-tape\n", drive->name);
4846 goto failed;
4847 }
4848 if (drive->scsi) {
4849 printk("ide-tape: passing drive %s to ide-scsi emulation.\n", drive->name);
4850 goto failed;
4851 }
4852 if (strstr(drive->id->model, "OnStream DI-")) {
4853 printk(KERN_WARNING "ide-tape: Use drive %s with ide-scsi emulation and osst.\n", drive->name);
4854 printk(KERN_WARNING "ide-tape: OnStream support will be removed soon from ide-tape!\n");
4855 }
4856 tape = (idetape_tape_t *) kmalloc (sizeof (idetape_tape_t), GFP_KERNEL);
4857 if (tape == NULL) {
4858 printk(KERN_ERR "ide-tape: %s: Can't allocate a tape structure\n", drive->name);
4859 goto failed;
4860 }
4861
4862 g = alloc_disk(1 << PARTN_BITS);
4863 if (!g)
4864 goto out_free_tape;
4865
4866 ide_init_disk(g, drive);
4867
4868 if (ide_register_subdriver(drive, &idetape_driver)) {
4869 printk(KERN_ERR "ide-tape: %s: Failed to register the driver with ide.c\n", drive->name);
4870 goto out_put_disk;
4871 }
4872
4873 memset(tape, 0, sizeof(*tape));
4874
4875 kref_init(&tape->kref);
4876
4877 tape->drive = drive;
4878 tape->driver = &idetape_driver;
4879 tape->disk = g;
4880
4881 g->private_data = &tape->driver;
4882
4883 drive->driver_data = tape;
4884
4885 down(&idetape_ref_sem);
4886 for (minor = 0; idetape_devs[minor]; minor++)
4887 ;
4888 idetape_devs[minor] = tape;
4889 up(&idetape_ref_sem);
4890
4891 idetape_setup(drive, tape, minor);
4892
4893 devfs_mk_cdev(MKDEV(HWIF(drive)->major, minor),
4894 S_IFCHR | S_IRUGO | S_IWUGO,
4895 "%s/mt", drive->devfs_name);
4896 devfs_mk_cdev(MKDEV(HWIF(drive)->major, minor + 128),
4897 S_IFCHR | S_IRUGO | S_IWUGO,
4898 "%s/mtn", drive->devfs_name);
4899
4900 g->number = devfs_register_tape(drive->devfs_name);
4901 g->fops = &idetape_block_ops;
4902 ide_register_region(g);
4903
4904 return 0;
4905out_put_disk:
4906 put_disk(g);
4907out_free_tape:
4908 kfree(tape);
4909failed:
4910 return 1;
4911}
4912
4913MODULE_DESCRIPTION("ATAPI Streaming TAPE Driver");
4914MODULE_LICENSE("GPL");
4915
4916static void __exit idetape_exit (void)
4917{
4918 ide_unregister_driver(&idetape_driver);
4919 unregister_chrdev(IDETAPE_MAJOR, "ht");
4920}
4921
4922/*
4923 * idetape_init will register the driver for each tape.
4924 */
4925static int idetape_init (void)
4926{
4927 if (register_chrdev(IDETAPE_MAJOR, "ht", &idetape_fops)) {
4928 printk(KERN_ERR "ide-tape: Failed to register character device interface\n");
4929 return -EBUSY;
4930 }
4931 ide_register_driver(&idetape_driver);
4932 return 0;
4933}
4934
4935module_init(idetape_init);
4936module_exit(idetape_exit);
4937MODULE_ALIAS_CHARDEV_MAJOR(IDETAPE_MAJOR);
generated by cgit v1.2.2 (git 2.25.0) at 2024-11-08 04:14:28 -0500