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[PATCH] Move read_mostly definition to asm/cache.h
[linux-2.6/mini2440.git] / drivers / scsi / st.c
blobd40e7c871c363274ec739314cb159aee32c3bd8a
1 /*
2 SCSI Tape Driver for Linux version 1.1 and newer. See the accompanying
3 file Documentation/scsi/st.txt for more information.
4
5 History:
6 Rewritten from Dwayne Forsyth's SCSI tape driver by Kai Makisara.
7 Contribution and ideas from several people including (in alphabetical
8 order) Klaus Ehrenfried, Eugene Exarevsky, Eric Lee Green, Wolfgang Denk,
9 Steve Hirsch, Andreas Koppenh"ofer, Michael Leodolter, Eyal Lebedinsky,
10 Michael Schaefer, J"org Weule, and Eric Youngdale.
11
12 Copyright 1992 - 2005 Kai Makisara
13 email Kai.Makisara@kolumbus.fi
14
15 Some small formal changes - aeb, 950809
16
17 Last modified: 18-JAN-1998 Richard Gooch <rgooch@atnf.csiro.au> Devfs support
18 */
19
20 static const char *verstr = "20050830";
21
22 #include <linux/module.h>
23
24 #include <linux/fs.h>
25 #include <linux/kernel.h>
26 #include <linux/sched.h>
27 #include <linux/mm.h>
28 #include <linux/init.h>
29 #include <linux/string.h>
30 #include <linux/errno.h>
31 #include <linux/mtio.h>
32 #include <linux/cdrom.h>
33 #include <linux/ioctl.h>
34 #include <linux/fcntl.h>
35 #include <linux/spinlock.h>
36 #include <linux/blkdev.h>
37 #include <linux/moduleparam.h>
38 #include <linux/cdev.h>
39 #include <linux/delay.h>
40 #include <linux/mutex.h>
41
42 #include <asm/uaccess.h>
43 #include <asm/dma.h>
44 #include <asm/system.h>
45
46 #include <scsi/scsi.h>
47 #include <scsi/scsi_dbg.h>
48 #include <scsi/scsi_device.h>
49 #include <scsi/scsi_driver.h>
50 #include <scsi/scsi_eh.h>
51 #include <scsi/scsi_host.h>
52 #include <scsi/scsi_ioctl.h>
53 #include <scsi/sg.h>
54
55
56 /* The driver prints some debugging information on the console if DEBUG
57 is defined and non-zero. */
58 #define DEBUG 0
59
60 #if DEBUG
61 /* The message level for the debug messages is currently set to KERN_NOTICE
62 so that people can easily see the messages. Later when the debugging messages
63 in the drivers are more widely classified, this may be changed to KERN_DEBUG. */
64 #define ST_DEB_MSG KERN_NOTICE
65 #define DEB(a) a
66 #define DEBC(a) if (debugging) { a ; }
67 #else
68 #define DEB(a)
69 #define DEBC(a)
70 #endif
71
72 #define ST_KILOBYTE 1024
73
74 #include "st_options.h"
75 #include "st.h"
76
77 static int buffer_kbs;
78 static int max_sg_segs;
79 static int try_direct_io = TRY_DIRECT_IO;
80 static int try_rdio = 1;
81 static int try_wdio = 1;
82
83 static int st_dev_max;
84 static int st_nr_dev;
85
86 static struct class *st_sysfs_class;
87
88 MODULE_AUTHOR("Kai Makisara");
89 MODULE_DESCRIPTION("SCSI tape (st) driver");
90 MODULE_LICENSE("GPL");
91 MODULE_ALIAS_CHARDEV_MAJOR(SCSI_TAPE_MAJOR);
92
93 /* Set 'perm' (4th argument) to 0 to disable module_param's definition
94 * of sysfs parameters (which module_param doesn't yet support).
95 * Sysfs parameters defined explicitly later.
96 */
97 module_param_named(buffer_kbs, buffer_kbs, int, 0);
98 MODULE_PARM_DESC(buffer_kbs, "Default driver buffer size for fixed block mode (KB; 32)");
99 module_param_named(max_sg_segs, max_sg_segs, int, 0);
100 MODULE_PARM_DESC(max_sg_segs, "Maximum number of scatter/gather segments to use (256)");
101 module_param_named(try_direct_io, try_direct_io, int, 0);
102 MODULE_PARM_DESC(try_direct_io, "Try direct I/O between user buffer and tape drive (1)");
103
104 /* Extra parameters for testing */
105 module_param_named(try_rdio, try_rdio, int, 0);
106 MODULE_PARM_DESC(try_rdio, "Try direct read i/o when possible");
107 module_param_named(try_wdio, try_wdio, int, 0);
108 MODULE_PARM_DESC(try_wdio, "Try direct write i/o when possible");
109
110 #ifndef MODULE
111 static int write_threshold_kbs; /* retained for compatibility */
112 static struct st_dev_parm {
113 char *name;
114 int *val;
115 } parms[] __initdata = {
116 {
117 "buffer_kbs", &buffer_kbs
118 },
119 { /* Retained for compatibility with 2.4 */
120 "write_threshold_kbs", &write_threshold_kbs
121 },
122 {
123 "max_sg_segs", NULL
124 },
125 {
126 "try_direct_io", &try_direct_io
127 }
128 };
129 #endif
130
131 /* Restrict the number of modes so that names for all are assigned */
132 #if ST_NBR_MODES > 16
133 #error "Maximum number of modes is 16"
134 #endif
135 /* Bit reversed order to get same names for same minors with all
136 mode counts */
137 static const char *st_formats[] = {
138 "", "r", "k", "s", "l", "t", "o", "u",
139 "m", "v", "p", "x", "a", "y", "q", "z"};
140
141 /* The default definitions have been moved to st_options.h */
142
143 #define ST_FIXED_BUFFER_SIZE (ST_FIXED_BUFFER_BLOCKS * ST_KILOBYTE)
144
145 /* The buffer size should fit into the 24 bits for length in the
146 6-byte SCSI read and write commands. */
147 #if ST_FIXED_BUFFER_SIZE >= (2 << 24 - 1)
148 #error "Buffer size should not exceed (2 << 24 - 1) bytes!"
149 #endif
150
151 static int debugging = DEBUG;
152
153 #define MAX_RETRIES 0
154 #define MAX_WRITE_RETRIES 0
155 #define MAX_READY_RETRIES 0
156 #define NO_TAPE NOT_READY
157
158 #define ST_TIMEOUT (900 * HZ)
159 #define ST_LONG_TIMEOUT (14000 * HZ)
160
161 /* Remove mode bits and auto-rewind bit (7) */
162 #define TAPE_NR(x) ( ((iminor(x) & ~255) >> (ST_NBR_MODE_BITS + 1)) | \
163 (iminor(x) & ~(-1 << ST_MODE_SHIFT)) )
164 #define TAPE_MODE(x) ((iminor(x) & ST_MODE_MASK) >> ST_MODE_SHIFT)
165
166 /* Construct the minor number from the device (d), mode (m), and non-rewind (n) data */
167 #define TAPE_MINOR(d, m, n) (((d & ~(255 >> (ST_NBR_MODE_BITS + 1))) << (ST_NBR_MODE_BITS + 1)) | \
168 (d & (255 >> (ST_NBR_MODE_BITS + 1))) | (m << ST_MODE_SHIFT) | ((n != 0) << 7) )
169
170 /* Internal ioctl to set both density (uppermost 8 bits) and blocksize (lower
171 24 bits) */
172 #define SET_DENS_AND_BLK 0x10001
173
174 static DEFINE_RWLOCK(st_dev_arr_lock);
175
176 static int st_fixed_buffer_size = ST_FIXED_BUFFER_SIZE;
177 static int st_max_sg_segs = ST_MAX_SG;
178
179 static struct scsi_tape **scsi_tapes = NULL;
180
181 static int modes_defined;
182
183 static struct st_buffer *new_tape_buffer(int, int, int);
184 static int enlarge_buffer(struct st_buffer *, int, int);
185 static void normalize_buffer(struct st_buffer *);
186 static int append_to_buffer(const char __user *, struct st_buffer *, int);
187 static int from_buffer(struct st_buffer *, char __user *, int);
188 static void move_buffer_data(struct st_buffer *, int);
189 static void buf_to_sg(struct st_buffer *, unsigned int);
190
191 static int sgl_map_user_pages(struct scatterlist *, const unsigned int,
192 unsigned long, size_t, int);
193 static int sgl_unmap_user_pages(struct scatterlist *, const unsigned int, int);
194
195 static int st_probe(struct device *);
196 static int st_remove(struct device *);
197
198 static void do_create_driverfs_files(void);
199 static void do_remove_driverfs_files(void);
200 static void do_create_class_files(struct scsi_tape *, int, int);
201
202 static struct scsi_driver st_template = {
203 .owner = THIS_MODULE,
204 .gendrv = {
205 .name = "st",
206 .probe = st_probe,
207 .remove = st_remove,
208 },
209 };
210
211 static int st_compression(struct scsi_tape *, int);
212
213 static int find_partition(struct scsi_tape *);
214 static int switch_partition(struct scsi_tape *);
215
216 static int st_int_ioctl(struct scsi_tape *, unsigned int, unsigned long);
217
218 static void scsi_tape_release(struct kref *);
219
220 #define to_scsi_tape(obj) container_of(obj, struct scsi_tape, kref)
221
222 static DEFINE_MUTEX(st_ref_mutex);
223
224 \f
225 #include "osst_detect.h"
226 #ifndef SIGS_FROM_OSST
227 #define SIGS_FROM_OSST \
228 {"OnStream", "SC-", "", "osst"}, \
229 {"OnStream", "DI-", "", "osst"}, \
230 {"OnStream", "DP-", "", "osst"}, \
231 {"OnStream", "USB", "", "osst"}, \
232 {"OnStream", "FW-", "", "osst"}
233 #endif
234
235 static struct scsi_tape *scsi_tape_get(int dev)
236 {
237 struct scsi_tape *STp = NULL;
238
239 mutex_lock(&st_ref_mutex);
240 write_lock(&st_dev_arr_lock);
241
242 if (dev < st_dev_max && scsi_tapes != NULL)
243 STp = scsi_tapes[dev];
244 if (!STp) goto out;
245
246 kref_get(&STp->kref);
247
248 if (!STp->device)
249 goto out_put;
250
251 if (scsi_device_get(STp->device))
252 goto out_put;
253
254 goto out;
255
256 out_put:
257 kref_put(&STp->kref, scsi_tape_release);
258 STp = NULL;
259 out:
260 write_unlock(&st_dev_arr_lock);
261 mutex_unlock(&st_ref_mutex);
262 return STp;
263 }
264
265 static void scsi_tape_put(struct scsi_tape *STp)
266 {
267 struct scsi_device *sdev = STp->device;
268
269 mutex_lock(&st_ref_mutex);
270 kref_put(&STp->kref, scsi_tape_release);
271 scsi_device_put(sdev);
272 mutex_unlock(&st_ref_mutex);
273 }
274
275 struct st_reject_data {
276 char *vendor;
277 char *model;
278 char *rev;
279 char *driver_hint; /* Name of the correct driver, NULL if unknown */
280 };
281
282 static struct st_reject_data reject_list[] = {
283 /* {"XXX", "Yy-", "", NULL}, example */
284 SIGS_FROM_OSST,
285 {NULL, }};
286
287 /* If the device signature is on the list of incompatible drives, the
288 function returns a pointer to the name of the correct driver (if known) */
289 static char * st_incompatible(struct scsi_device* SDp)
290 {
291 struct st_reject_data *rp;
292
293 for (rp=&(reject_list[0]); rp->vendor != NULL; rp++)
294 if (!strncmp(rp->vendor, SDp->vendor, strlen(rp->vendor)) &&
295 !strncmp(rp->model, SDp->model, strlen(rp->model)) &&
296 !strncmp(rp->rev, SDp->rev, strlen(rp->rev))) {
297 if (rp->driver_hint)
298 return rp->driver_hint;
299 else
300 return "unknown";
301 }
302 return NULL;
303 }
304 \f
305
306 static inline char *tape_name(struct scsi_tape *tape)
307 {
308 return tape->disk->disk_name;
309 }
310
311
312 static void st_analyze_sense(struct st_request *SRpnt, struct st_cmdstatus *s)
313 {
314 const u8 *ucp;
315 const u8 *sense = SRpnt->sense;
316
317 s->have_sense = scsi_normalize_sense(SRpnt->sense,
318 SCSI_SENSE_BUFFERSIZE, &s->sense_hdr);
319 s->flags = 0;
320
321 if (s->have_sense) {
322 s->deferred = 0;
323 s->remainder_valid =
324 scsi_get_sense_info_fld(sense, SCSI_SENSE_BUFFERSIZE, &s->uremainder64);
325 switch (sense[0] & 0x7f) {
326 case 0x71:
327 s->deferred = 1;
328 case 0x70:
329 s->fixed_format = 1;
330 s->flags = sense[2] & 0xe0;
331 break;
332 case 0x73:
333 s->deferred = 1;
334 case 0x72:
335 s->fixed_format = 0;
336 ucp = scsi_sense_desc_find(sense, SCSI_SENSE_BUFFERSIZE, 4);
337 s->flags = ucp ? (ucp[3] & 0xe0) : 0;
338 break;
339 }
340 }
341 }
342
343
344 /* Convert the result to success code */
345 static int st_chk_result(struct scsi_tape *STp, struct st_request * SRpnt)
346 {
347 int result = SRpnt->result;
348 u8 scode;
349 DEB(const char *stp;)
350 char *name = tape_name(STp);
351 struct st_cmdstatus *cmdstatp;
352
353 if (!result)
354 return 0;
355
356 cmdstatp = &STp->buffer->cmdstat;
357 st_analyze_sense(SRpnt, cmdstatp);
358
359 if (cmdstatp->have_sense)
360 scode = STp->buffer->cmdstat.sense_hdr.sense_key;
361 else
362 scode = 0;
363
364 DEB(
365 if (debugging) {
366 printk(ST_DEB_MSG "%s: Error: %x, cmd: %x %x %x %x %x %x\n",
367 name, result,
368 SRpnt->cmd[0], SRpnt->cmd[1], SRpnt->cmd[2],
369 SRpnt->cmd[3], SRpnt->cmd[4], SRpnt->cmd[5]);
370 if (cmdstatp->have_sense)
371 __scsi_print_sense("st", SRpnt->sense, SCSI_SENSE_BUFFERSIZE);
372 } ) /* end DEB */
373 if (!debugging) { /* Abnormal conditions for tape */
374 if (!cmdstatp->have_sense)
375 printk(KERN_WARNING
376 "%s: Error %x (sugg. bt 0x%x, driver bt 0x%x, host bt 0x%x).\n",
377 name, result, suggestion(result),
378 driver_byte(result) & DRIVER_MASK, host_byte(result));
379 else if (cmdstatp->have_sense &&
380 scode != NO_SENSE &&
381 scode != RECOVERED_ERROR &&
382 /* scode != UNIT_ATTENTION && */
383 scode != BLANK_CHECK &&
384 scode != VOLUME_OVERFLOW &&
385 SRpnt->cmd[0] != MODE_SENSE &&
386 SRpnt->cmd[0] != TEST_UNIT_READY) {
387 printk(KERN_WARNING "%s: Error with sense data: ", name);
388 __scsi_print_sense("st", SRpnt->sense,
389 SCSI_SENSE_BUFFERSIZE);
390 }
391 }
392
393 if (cmdstatp->fixed_format &&
394 STp->cln_mode >= EXTENDED_SENSE_START) { /* Only fixed format sense */
395 if (STp->cln_sense_value)
396 STp->cleaning_req |= ((SRpnt->sense[STp->cln_mode] &
397 STp->cln_sense_mask) == STp->cln_sense_value);
398 else
399 STp->cleaning_req |= ((SRpnt->sense[STp->cln_mode] &
400 STp->cln_sense_mask) != 0);
401 }
402 if (cmdstatp->have_sense &&
403 cmdstatp->sense_hdr.asc == 0 && cmdstatp->sense_hdr.ascq == 0x17)
404 STp->cleaning_req = 1; /* ASC and ASCQ => cleaning requested */
405
406 STp->pos_unknown |= STp->device->was_reset;
407
408 if (cmdstatp->have_sense &&
409 scode == RECOVERED_ERROR
410 #if ST_RECOVERED_WRITE_FATAL
411 && SRpnt->cmd[0] != WRITE_6
412 && SRpnt->cmd[0] != WRITE_FILEMARKS
413 #endif
414 ) {
415 STp->recover_count++;
416 STp->recover_reg++;
417
418 DEB(
419 if (debugging) {
420 if (SRpnt->cmd[0] == READ_6)
421 stp = "read";
422 else if (SRpnt->cmd[0] == WRITE_6)
423 stp = "write";
424 else
425 stp = "ioctl";
426 printk(ST_DEB_MSG "%s: Recovered %s error (%d).\n", name, stp,
427 STp->recover_count);
428 } ) /* end DEB */
429
430 if (cmdstatp->flags == 0)
431 return 0;
432 }
433 return (-EIO);
434 }
435
436
437 /* Wakeup from interrupt */
438 static void st_sleep_done(void *data, char *sense, int result, int resid)
439 {
440 struct st_request *SRpnt = data;
441 struct scsi_tape *STp = SRpnt->stp;
442
443 memcpy(SRpnt->sense, sense, SCSI_SENSE_BUFFERSIZE);
444 (STp->buffer)->cmdstat.midlevel_result = SRpnt->result = result;
445 DEB( STp->write_pending = 0; )
446
447 if (SRpnt->waiting)
448 complete(SRpnt->waiting);
449 }
450
451 static struct st_request *st_allocate_request(void)
452 {
453 return kzalloc(sizeof(struct st_request), GFP_KERNEL);
454 }
455
456 static void st_release_request(struct st_request *streq)
457 {
458 kfree(streq);
459 }
460
461 /* Do the scsi command. Waits until command performed if do_wait is true.
462 Otherwise write_behind_check() is used to check that the command
463 has finished. */
464 static struct st_request *
465 st_do_scsi(struct st_request * SRpnt, struct scsi_tape * STp, unsigned char *cmd,
466 int bytes, int direction, int timeout, int retries, int do_wait)
467 {
468 struct completion *waiting;
469
470 /* if async, make sure there's no command outstanding */
471 if (!do_wait && ((STp->buffer)->last_SRpnt)) {
472 printk(KERN_ERR "%s: Async command already active.\n",
473 tape_name(STp));
474 if (signal_pending(current))
475 (STp->buffer)->syscall_result = (-EINTR);
476 else
477 (STp->buffer)->syscall_result = (-EBUSY);
478 return NULL;
479 }
480
481 if (SRpnt == NULL) {
482 SRpnt = st_allocate_request();
483 if (SRpnt == NULL) {
484 DEBC( printk(KERN_ERR "%s: Can't get SCSI request.\n",
485 tape_name(STp)); );
486 if (signal_pending(current))
487 (STp->buffer)->syscall_result = (-EINTR);
488 else
489 (STp->buffer)->syscall_result = (-EBUSY);
490 return NULL;
491 }
492 SRpnt->stp = STp;
493 }
494
495 /* If async IO, set last_SRpnt. This ptr tells write_behind_check
496 which IO is outstanding. It's nulled out when the IO completes. */
497 if (!do_wait)
498 (STp->buffer)->last_SRpnt = SRpnt;
499
500 waiting = &STp->wait;
501 init_completion(waiting);
502 SRpnt->waiting = waiting;
503
504 if (!STp->buffer->do_dio)
505 buf_to_sg(STp->buffer, bytes);
506
507 memcpy(SRpnt->cmd, cmd, sizeof(SRpnt->cmd));
508 STp->buffer->cmdstat.have_sense = 0;
509 STp->buffer->syscall_result = 0;
510
511 if (scsi_execute_async(STp->device, cmd, COMMAND_SIZE(cmd[0]), direction,
512 &((STp->buffer)->sg[0]), bytes, (STp->buffer)->sg_segs,
513 timeout, retries, SRpnt, st_sleep_done, GFP_KERNEL)) {
514 /* could not allocate the buffer or request was too large */
515 (STp->buffer)->syscall_result = (-EBUSY);
516 (STp->buffer)->last_SRpnt = NULL;
517 }
518 else if (do_wait) {
519 wait_for_completion(waiting);
520 SRpnt->waiting = NULL;
521 (STp->buffer)->syscall_result = st_chk_result(STp, SRpnt);
522 }
523
524 return SRpnt;
525 }
526
527
528 /* Handle the write-behind checking (waits for completion). Returns -ENOSPC if
529 write has been correct but EOM early warning reached, -EIO if write ended in
530 error or zero if write successful. Asynchronous writes are used only in
531 variable block mode. */
532 static int write_behind_check(struct scsi_tape * STp)
533 {
534 int retval = 0;
535 struct st_buffer *STbuffer;
536 struct st_partstat *STps;
537 struct st_cmdstatus *cmdstatp;
538 struct st_request *SRpnt;
539
540 STbuffer = STp->buffer;
541 if (!STbuffer->writing)
542 return 0;
543
544 DEB(
545 if (STp->write_pending)
546 STp->nbr_waits++;
547 else
548 STp->nbr_finished++;
549 ) /* end DEB */
550
551 wait_for_completion(&(STp->wait));
552 SRpnt = STbuffer->last_SRpnt;
553 STbuffer->last_SRpnt = NULL;
554 SRpnt->waiting = NULL;
555
556 (STp->buffer)->syscall_result = st_chk_result(STp, SRpnt);
557 st_release_request(SRpnt);
558
559 STbuffer->buffer_bytes -= STbuffer->writing;
560 STps = &(STp->ps[STp->partition]);
561 if (STps->drv_block >= 0) {
562 if (STp->block_size == 0)
563 STps->drv_block++;
564 else
565 STps->drv_block += STbuffer->writing / STp->block_size;
566 }
567
568 cmdstatp = &STbuffer->cmdstat;
569 if (STbuffer->syscall_result) {
570 retval = -EIO;
571 if (cmdstatp->have_sense && !cmdstatp->deferred &&
572 (cmdstatp->flags & SENSE_EOM) &&
573 (cmdstatp->sense_hdr.sense_key == NO_SENSE ||
574 cmdstatp->sense_hdr.sense_key == RECOVERED_ERROR)) {
575 /* EOM at write-behind, has all data been written? */
576 if (!cmdstatp->remainder_valid ||
577 cmdstatp->uremainder64 == 0)
578 retval = -ENOSPC;
579 }
580 if (retval == -EIO)
581 STps->drv_block = -1;
582 }
583 STbuffer->writing = 0;
584
585 DEB(if (debugging && retval)
586 printk(ST_DEB_MSG "%s: Async write error %x, return value %d.\n",
587 tape_name(STp), STbuffer->cmdstat.midlevel_result, retval);) /* end DEB */
588
589 return retval;
590 }
591
592
593 /* Step over EOF if it has been inadvertently crossed (ioctl not used because
594 it messes up the block number). */
595 static int cross_eof(struct scsi_tape * STp, int forward)
596 {
597 struct st_request *SRpnt;
598 unsigned char cmd[MAX_COMMAND_SIZE];
599
600 cmd[0] = SPACE;
601 cmd[1] = 0x01; /* Space FileMarks */
602 if (forward) {
603 cmd[2] = cmd[3] = 0;
604 cmd[4] = 1;
605 } else
606 cmd[2] = cmd[3] = cmd[4] = 0xff; /* -1 filemarks */
607 cmd[5] = 0;
608
609 DEBC(printk(ST_DEB_MSG "%s: Stepping over filemark %s.\n",
610 tape_name(STp), forward ? "forward" : "backward"));
611
612 SRpnt = st_do_scsi(NULL, STp, cmd, 0, DMA_NONE,
613 STp->device->timeout, MAX_RETRIES, 1);
614 if (!SRpnt)
615 return (STp->buffer)->syscall_result;
616
617 st_release_request(SRpnt);
618 SRpnt = NULL;
619
620 if ((STp->buffer)->cmdstat.midlevel_result != 0)
621 printk(KERN_ERR "%s: Stepping over filemark %s failed.\n",
622 tape_name(STp), forward ? "forward" : "backward");
623
624 return (STp->buffer)->syscall_result;
625 }
626
627
628 /* Flush the write buffer (never need to write if variable blocksize). */
629 static int flush_write_buffer(struct scsi_tape * STp)
630 {
631 int offset, transfer, blks;
632 int result;
633 unsigned char cmd[MAX_COMMAND_SIZE];
634 struct st_request *SRpnt;
635 struct st_partstat *STps;
636
637 result = write_behind_check(STp);
638 if (result)
639 return result;
640
641 result = 0;
642 if (STp->dirty == 1) {
643
644 offset = (STp->buffer)->buffer_bytes;
645 transfer = ((offset + STp->block_size - 1) /
646 STp->block_size) * STp->block_size;
647 DEBC(printk(ST_DEB_MSG "%s: Flushing %d bytes.\n",
648 tape_name(STp), transfer));
649
650 memset((STp->buffer)->b_data + offset, 0, transfer - offset);
651
652 memset(cmd, 0, MAX_COMMAND_SIZE);
653 cmd[0] = WRITE_6;
654 cmd[1] = 1;
655 blks = transfer / STp->block_size;
656 cmd[2] = blks >> 16;
657 cmd[3] = blks >> 8;
658 cmd[4] = blks;
659
660 SRpnt = st_do_scsi(NULL, STp, cmd, transfer, DMA_TO_DEVICE,
661 STp->device->timeout, MAX_WRITE_RETRIES, 1);
662 if (!SRpnt)
663 return (STp->buffer)->syscall_result;
664
665 STps = &(STp->ps[STp->partition]);
666 if ((STp->buffer)->syscall_result != 0) {
667 struct st_cmdstatus *cmdstatp = &STp->buffer->cmdstat;
668
669 if (cmdstatp->have_sense && !cmdstatp->deferred &&
670 (cmdstatp->flags & SENSE_EOM) &&
671 (cmdstatp->sense_hdr.sense_key == NO_SENSE ||
672 cmdstatp->sense_hdr.sense_key == RECOVERED_ERROR) &&
673 (!cmdstatp->remainder_valid ||
674 cmdstatp->uremainder64 == 0)) { /* All written at EOM early warning */
675 STp->dirty = 0;
676 (STp->buffer)->buffer_bytes = 0;
677 if (STps->drv_block >= 0)
678 STps->drv_block += blks;
679 result = (-ENOSPC);
680 } else {
681 printk(KERN_ERR "%s: Error on flush.\n",
682 tape_name(STp));
683 STps->drv_block = (-1);
684 result = (-EIO);
685 }
686 } else {
687 if (STps->drv_block >= 0)
688 STps->drv_block += blks;
689 STp->dirty = 0;
690 (STp->buffer)->buffer_bytes = 0;
691 }
692 st_release_request(SRpnt);
693 SRpnt = NULL;
694 }
695 return result;
696 }
697
698
699 /* Flush the tape buffer. The tape will be positioned correctly unless
700 seek_next is true. */
701 static int flush_buffer(struct scsi_tape *STp, int seek_next)
702 {
703 int backspace, result;
704 struct st_buffer *STbuffer;
705 struct st_partstat *STps;
706
707 STbuffer = STp->buffer;
708
709 /*
710 * If there was a bus reset, block further access
711 * to this device.
712 */
713 if (STp->pos_unknown)
714 return (-EIO);
715
716 if (STp->ready != ST_READY)
717 return 0;
718 STps = &(STp->ps[STp->partition]);
719 if (STps->rw == ST_WRITING) /* Writing */
720 return flush_write_buffer(STp);
721
722 if (STp->block_size == 0)
723 return 0;
724
725 backspace = ((STp->buffer)->buffer_bytes +
726 (STp->buffer)->read_pointer) / STp->block_size -
727 ((STp->buffer)->read_pointer + STp->block_size - 1) /
728 STp->block_size;
729 (STp->buffer)->buffer_bytes = 0;
730 (STp->buffer)->read_pointer = 0;
731 result = 0;
732 if (!seek_next) {
733 if (STps->eof == ST_FM_HIT) {
734 result = cross_eof(STp, 0); /* Back over the EOF hit */
735 if (!result)
736 STps->eof = ST_NOEOF;
737 else {
738 if (STps->drv_file >= 0)
739 STps->drv_file++;
740 STps->drv_block = 0;
741 }
742 }
743 if (!result && backspace > 0)
744 result = st_int_ioctl(STp, MTBSR, backspace);
745 } else if (STps->eof == ST_FM_HIT) {
746 if (STps->drv_file >= 0)
747 STps->drv_file++;
748 STps->drv_block = 0;
749 STps->eof = ST_NOEOF;
750 }
751 return result;
752
753 }
754 \f
755 /* Set the mode parameters */
756 static int set_mode_densblk(struct scsi_tape * STp, struct st_modedef * STm)
757 {
758 int set_it = 0;
759 unsigned long arg;
760 char *name = tape_name(STp);
761
762 if (!STp->density_changed &&
763 STm->default_density >= 0 &&
764 STm->default_density != STp->density) {
765 arg = STm->default_density;
766 set_it = 1;
767 } else
768 arg = STp->density;
769 arg <<= MT_ST_DENSITY_SHIFT;
770 if (!STp->blksize_changed &&
771 STm->default_blksize >= 0 &&
772 STm->default_blksize != STp->block_size) {
773 arg |= STm->default_blksize;
774 set_it = 1;
775 } else
776 arg |= STp->block_size;
777 if (set_it &&
778 st_int_ioctl(STp, SET_DENS_AND_BLK, arg)) {
779 printk(KERN_WARNING
780 "%s: Can't set default block size to %d bytes and density %x.\n",
781 name, STm->default_blksize, STm->default_density);
782 if (modes_defined)
783 return (-EINVAL);
784 }
785 return 0;
786 }
787
788
789 /* Lock or unlock the drive door. Don't use when st_request allocated. */
790 static int do_door_lock(struct scsi_tape * STp, int do_lock)
791 {
792 int retval, cmd;
793 DEB(char *name = tape_name(STp);)
794
795
796 cmd = do_lock ? SCSI_IOCTL_DOORLOCK : SCSI_IOCTL_DOORUNLOCK;
797 DEBC(printk(ST_DEB_MSG "%s: %socking drive door.\n", name,
798 do_lock ? "L" : "Unl"));
799 retval = scsi_ioctl(STp->device, cmd, NULL);
800 if (!retval) {
801 STp->door_locked = do_lock ? ST_LOCKED_EXPLICIT : ST_UNLOCKED;
802 }
803 else {
804 STp->door_locked = ST_LOCK_FAILS;
805 }
806 return retval;
807 }
808
809
810 /* Set the internal state after reset */
811 static void reset_state(struct scsi_tape *STp)
812 {
813 int i;
814 struct st_partstat *STps;
815
816 STp->pos_unknown = 0;
817 for (i = 0; i < ST_NBR_PARTITIONS; i++) {
818 STps = &(STp->ps[i]);
819 STps->rw = ST_IDLE;
820 STps->eof = ST_NOEOF;
821 STps->at_sm = 0;
822 STps->last_block_valid = 0;
823 STps->drv_block = -1;
824 STps->drv_file = -1;
825 }
826 if (STp->can_partitions) {
827 STp->partition = find_partition(STp);
828 if (STp->partition < 0)
829 STp->partition = 0;
830 STp->new_partition = STp->partition;
831 }
832 }
833 \f
834 /* Test if the drive is ready. Returns either one of the codes below or a negative system
835 error code. */
836 #define CHKRES_READY 0
837 #define CHKRES_NEW_SESSION 1
838 #define CHKRES_NOT_READY 2
839 #define CHKRES_NO_TAPE 3
840
841 #define MAX_ATTENTIONS 10
842
843 static int test_ready(struct scsi_tape *STp, int do_wait)
844 {
845 int attentions, waits, max_wait, scode;
846 int retval = CHKRES_READY, new_session = 0;
847 unsigned char cmd[MAX_COMMAND_SIZE];
848 struct st_request *SRpnt = NULL;
849 struct st_cmdstatus *cmdstatp = &STp->buffer->cmdstat;
850
851 max_wait = do_wait ? ST_BLOCK_SECONDS : 0;
852
853 for (attentions=waits=0; ; ) {
854 memset((void *) &cmd[0], 0, MAX_COMMAND_SIZE);
855 cmd[0] = TEST_UNIT_READY;
856 SRpnt = st_do_scsi(SRpnt, STp, cmd, 0, DMA_NONE,
857 STp->long_timeout, MAX_READY_RETRIES, 1);
858
859 if (!SRpnt) {
860 retval = (STp->buffer)->syscall_result;
861 break;
862 }
863
864 if (cmdstatp->have_sense) {
865
866 scode = cmdstatp->sense_hdr.sense_key;
867
868 if (scode == UNIT_ATTENTION) { /* New media? */
869 new_session = 1;
870 if (attentions < MAX_ATTENTIONS) {
871 attentions++;
872 continue;
873 }
874 else {
875 retval = (-EIO);
876 break;
877 }
878 }
879
880 if (scode == NOT_READY) {
881 if (waits < max_wait) {
882 if (msleep_interruptible(1000)) {
883 retval = (-EINTR);
884 break;
885 }
886 waits++;
887 continue;
888 }
889 else {
890 if ((STp->device)->scsi_level >= SCSI_2 &&
891 cmdstatp->sense_hdr.asc == 0x3a) /* Check ASC */
892 retval = CHKRES_NO_TAPE;
893 else
894 retval = CHKRES_NOT_READY;
895 break;
896 }
897 }
898 }
899
900 retval = (STp->buffer)->syscall_result;
901 if (!retval)
902 retval = new_session ? CHKRES_NEW_SESSION : CHKRES_READY;
903 break;
904 }
905
906 if (SRpnt != NULL)
907 st_release_request(SRpnt);
908 return retval;
909 }
910
911
912 /* See if the drive is ready and gather information about the tape. Return values:
913 < 0 negative error code from errno.h
914 0 drive ready
915 1 drive not ready (possibly no tape)
916 */
917 static int check_tape(struct scsi_tape *STp, struct file *filp)
918 {
919 int i, retval, new_session = 0, do_wait;
920 unsigned char cmd[MAX_COMMAND_SIZE], saved_cleaning;
921 unsigned short st_flags = filp->f_flags;
922 struct st_request *SRpnt = NULL;
923 struct st_modedef *STm;
924 struct st_partstat *STps;
925 char *name = tape_name(STp);
926 struct inode *inode = filp->f_dentry->d_inode;
927 int mode = TAPE_MODE(inode);
928
929 STp->ready = ST_READY;
930
931 if (mode != STp->current_mode) {
932 DEBC(printk(ST_DEB_MSG "%s: Mode change from %d to %d.\n",
933 name, STp->current_mode, mode));
934 new_session = 1;
935 STp->current_mode = mode;
936 }
937 STm = &(STp->modes[STp->current_mode]);
938
939 saved_cleaning = STp->cleaning_req;
940 STp->cleaning_req = 0;
941
942 do_wait = ((filp->f_flags & O_NONBLOCK) == 0);
943 retval = test_ready(STp, do_wait);
944
945 if (retval < 0)
946 goto err_out;
947
948 if (retval == CHKRES_NEW_SESSION) {
949 STp->pos_unknown = 0;
950 STp->partition = STp->new_partition = 0;
951 if (STp->can_partitions)
952 STp->nbr_partitions = 1; /* This guess will be updated later
953 if necessary */
954 for (i = 0; i < ST_NBR_PARTITIONS; i++) {
955 STps = &(STp->ps[i]);
956 STps->rw = ST_IDLE;
957 STps->eof = ST_NOEOF;
958 STps->at_sm = 0;
959 STps->last_block_valid = 0;
960 STps->drv_block = 0;
961 STps->drv_file = 0;
962 }
963 new_session = 1;
964 }
965 else {
966 STp->cleaning_req |= saved_cleaning;
967
968 if (retval == CHKRES_NOT_READY || retval == CHKRES_NO_TAPE) {
969 if (retval == CHKRES_NO_TAPE)
970 STp->ready = ST_NO_TAPE;
971 else
972 STp->ready = ST_NOT_READY;
973
974 STp->density = 0; /* Clear the erroneous "residue" */
975 STp->write_prot = 0;
976 STp->block_size = 0;
977 STp->ps[0].drv_file = STp->ps[0].drv_block = (-1);
978 STp->partition = STp->new_partition = 0;
979 STp->door_locked = ST_UNLOCKED;
980 return CHKRES_NOT_READY;
981 }
982 }
983
984 if (STp->omit_blklims)
985 STp->min_block = STp->max_block = (-1);
986 else {
987 memset((void *) &cmd[0], 0, MAX_COMMAND_SIZE);
988 cmd[0] = READ_BLOCK_LIMITS;
989
990 SRpnt = st_do_scsi(SRpnt, STp, cmd, 6, DMA_FROM_DEVICE,
991 STp->device->timeout, MAX_READY_RETRIES, 1);
992 if (!SRpnt) {
993 retval = (STp->buffer)->syscall_result;
994 goto err_out;
995 }
996
997 if (!SRpnt->result && !STp->buffer->cmdstat.have_sense) {
998 STp->max_block = ((STp->buffer)->b_data[1] << 16) |
999 ((STp->buffer)->b_data[2] << 8) | (STp->buffer)->b_data[3];
1000 STp->min_block = ((STp->buffer)->b_data[4] << 8) |
1001 (STp->buffer)->b_data[5];
1002 if ( DEB( debugging || ) !STp->inited)
1003 printk(KERN_WARNING
1004 "%s: Block limits %d - %d bytes.\n", name,
1005 STp->min_block, STp->max_block);
1006 } else {
1007 STp->min_block = STp->max_block = (-1);
1008 DEBC(printk(ST_DEB_MSG "%s: Can't read block limits.\n",
1009 name));
1010 }
1011 }
1012
1013 memset((void *) &cmd[0], 0, MAX_COMMAND_SIZE);
1014 cmd[0] = MODE_SENSE;
1015 cmd[4] = 12;
1016
1017 SRpnt = st_do_scsi(SRpnt, STp, cmd, 12, DMA_FROM_DEVICE,
1018 STp->device->timeout, MAX_READY_RETRIES, 1);
1019 if (!SRpnt) {
1020 retval = (STp->buffer)->syscall_result;
1021 goto err_out;
1022 }
1023
1024 if ((STp->buffer)->syscall_result != 0) {
1025 DEBC(printk(ST_DEB_MSG "%s: No Mode Sense.\n", name));
1026 STp->block_size = ST_DEFAULT_BLOCK; /* Educated guess (?) */
1027 (STp->buffer)->syscall_result = 0; /* Prevent error propagation */
1028 STp->drv_write_prot = 0;
1029 } else {
1030 DEBC(printk(ST_DEB_MSG
1031 "%s: Mode sense. Length %d, medium %x, WBS %x, BLL %d\n",
1032 name,
1033 (STp->buffer)->b_data[0], (STp->buffer)->b_data[1],
1034 (STp->buffer)->b_data[2], (STp->buffer)->b_data[3]));
1035
1036 if ((STp->buffer)->b_data[3] >= 8) {
1037 STp->drv_buffer = ((STp->buffer)->b_data[2] >> 4) & 7;
1038 STp->density = (STp->buffer)->b_data[4];
1039 STp->block_size = (STp->buffer)->b_data[9] * 65536 +
1040 (STp->buffer)->b_data[10] * 256 + (STp->buffer)->b_data[11];
1041 DEBC(printk(ST_DEB_MSG
1042 "%s: Density %x, tape length: %x, drv buffer: %d\n",
1043 name, STp->density, (STp->buffer)->b_data[5] * 65536 +
1044 (STp->buffer)->b_data[6] * 256 + (STp->buffer)->b_data[7],
1045 STp->drv_buffer));
1046 }
1047 STp->drv_write_prot = ((STp->buffer)->b_data[2] & 0x80) != 0;
1048 }
1049 st_release_request(SRpnt);
1050 SRpnt = NULL;
1051 STp->inited = 1;
1052
1053 if (STp->block_size > 0)
1054 (STp->buffer)->buffer_blocks =
1055 (STp->buffer)->buffer_size / STp->block_size;
1056 else
1057 (STp->buffer)->buffer_blocks = 1;
1058 (STp->buffer)->buffer_bytes = (STp->buffer)->read_pointer = 0;
1059
1060 DEBC(printk(ST_DEB_MSG
1061 "%s: Block size: %d, buffer size: %d (%d blocks).\n", name,
1062 STp->block_size, (STp->buffer)->buffer_size,
1063 (STp->buffer)->buffer_blocks));
1064
1065 if (STp->drv_write_prot) {
1066 STp->write_prot = 1;
1067
1068 DEBC(printk(ST_DEB_MSG "%s: Write protected\n", name));
1069
1070 if (do_wait &&
1071 ((st_flags & O_ACCMODE) == O_WRONLY ||
1072 (st_flags & O_ACCMODE) == O_RDWR)) {
1073 retval = (-EROFS);
1074 goto err_out;
1075 }
1076 }
1077
1078 if (STp->can_partitions && STp->nbr_partitions < 1) {
1079 /* This code is reached when the device is opened for the first time
1080 after the driver has been initialized with tape in the drive and the
1081 partition support has been enabled. */
1082 DEBC(printk(ST_DEB_MSG
1083 "%s: Updating partition number in status.\n", name));
1084 if ((STp->partition = find_partition(STp)) < 0) {
1085 retval = STp->partition;
1086 goto err_out;
1087 }
1088 STp->new_partition = STp->partition;
1089 STp->nbr_partitions = 1; /* This guess will be updated when necessary */
1090 }
1091
1092 if (new_session) { /* Change the drive parameters for the new mode */
1093 STp->density_changed = STp->blksize_changed = 0;
1094 STp->compression_changed = 0;
1095 if (!(STm->defaults_for_writes) &&
1096 (retval = set_mode_densblk(STp, STm)) < 0)
1097 goto err_out;
1098
1099 if (STp->default_drvbuffer != 0xff) {
1100 if (st_int_ioctl(STp, MTSETDRVBUFFER, STp->default_drvbuffer))
1101 printk(KERN_WARNING
1102 "%s: Can't set default drive buffering to %d.\n",
1103 name, STp->default_drvbuffer);
1104 }
1105 }
1106
1107 return CHKRES_READY;
1108
1109 err_out:
1110 return retval;
1111 }
1112
1113
1114 \f/* Open the device. Needs to be called with BKL only because of incrementing the SCSI host
1115 module count. */
1116 static int st_open(struct inode *inode, struct file *filp)
1117 {
1118 int i, retval = (-EIO);
1119 struct scsi_tape *STp;
1120 struct st_partstat *STps;
1121 int dev = TAPE_NR(inode);
1122 char *name;
1123
1124 /*
1125 * We really want to do nonseekable_open(inode, filp); here, but some
1126 * versions of tar incorrectly call lseek on tapes and bail out if that
1127 * fails. So we disallow pread() and pwrite(), but permit lseeks.
1128 */
1129 filp->f_mode &= ~(FMODE_PREAD | FMODE_PWRITE);
1130
1131 if (!(STp = scsi_tape_get(dev)))
1132 return -ENXIO;
1133
1134 write_lock(&st_dev_arr_lock);
1135 filp->private_data = STp;
1136 name = tape_name(STp);
1137
1138 if (STp->in_use) {
1139 write_unlock(&st_dev_arr_lock);
1140 scsi_tape_put(STp);
1141 DEB( printk(ST_DEB_MSG "%s: Device already in use.\n", name); )
1142 return (-EBUSY);
1143 }
1144
1145 STp->in_use = 1;
1146 write_unlock(&st_dev_arr_lock);
1147 STp->rew_at_close = STp->autorew_dev = (iminor(inode) & 0x80) == 0;
1148
1149 if (!scsi_block_when_processing_errors(STp->device)) {
1150 retval = (-ENXIO);
1151 goto err_out;
1152 }
1153
1154 /* See that we have at least a one page buffer available */
1155 if (!enlarge_buffer(STp->buffer, PAGE_SIZE, STp->restr_dma)) {
1156 printk(KERN_WARNING "%s: Can't allocate one page tape buffer.\n",
1157 name);
1158 retval = (-EOVERFLOW);
1159 goto err_out;
1160 }
1161
1162 (STp->buffer)->writing = 0;
1163 (STp->buffer)->syscall_result = 0;
1164
1165 STp->write_prot = ((filp->f_flags & O_ACCMODE) == O_RDONLY);
1166
1167 STp->dirty = 0;
1168 for (i = 0; i < ST_NBR_PARTITIONS; i++) {
1169 STps = &(STp->ps[i]);
1170 STps->rw = ST_IDLE;
1171 }
1172 STp->recover_count = 0;
1173 DEB( STp->nbr_waits = STp->nbr_finished = 0;
1174 STp->nbr_requests = STp->nbr_dio = STp->nbr_pages = STp->nbr_combinable = 0; )
1175
1176 retval = check_tape(STp, filp);
1177 if (retval < 0)
1178 goto err_out;
1179 if ((filp->f_flags & O_NONBLOCK) == 0 &&
1180 retval != CHKRES_READY) {
1181 retval = (-EIO);
1182 goto err_out;
1183 }
1184 return 0;
1185
1186 err_out:
1187 normalize_buffer(STp->buffer);
1188 STp->in_use = 0;
1189 scsi_tape_put(STp);
1190 return retval;
1191
1192 }
1193 \f
1194
1195 /* Flush the tape buffer before close */
1196 static int st_flush(struct file *filp)
1197 {
1198 int result = 0, result2;
1199 unsigned char cmd[MAX_COMMAND_SIZE];
1200 struct st_request *SRpnt;
1201 struct scsi_tape *STp = filp->private_data;
1202 struct st_modedef *STm = &(STp->modes[STp->current_mode]);
1203 struct st_partstat *STps = &(STp->ps[STp->partition]);
1204 char *name = tape_name(STp);
1205
1206 if (file_count(filp) > 1)
1207 return 0;
1208
1209 if (STps->rw == ST_WRITING && !STp->pos_unknown) {
1210 result = flush_write_buffer(STp);
1211 if (result != 0 && result != (-ENOSPC))
1212 goto out;
1213 }
1214
1215 if (STp->can_partitions &&
1216 (result2 = switch_partition(STp)) < 0) {
1217 DEBC(printk(ST_DEB_MSG
1218 "%s: switch_partition at close failed.\n", name));
1219 if (result == 0)
1220 result = result2;
1221 goto out;
1222 }
1223
1224 DEBC( if (STp->nbr_requests)
1225 printk(KERN_WARNING "%s: Number of r/w requests %d, dio used in %d, pages %d (%d).\n",
1226 name, STp->nbr_requests, STp->nbr_dio, STp->nbr_pages, STp->nbr_combinable));
1227
1228 if (STps->rw == ST_WRITING && !STp->pos_unknown) {
1229 struct st_cmdstatus *cmdstatp = &STp->buffer->cmdstat;
1230
1231 DEBC(printk(ST_DEB_MSG "%s: Async write waits %d, finished %d.\n",
1232 name, STp->nbr_waits, STp->nbr_finished);
1233 )
1234
1235 memset(cmd, 0, MAX_COMMAND_SIZE);
1236 cmd[0] = WRITE_FILEMARKS;
1237 cmd[4] = 1 + STp->two_fm;
1238
1239 SRpnt = st_do_scsi(NULL, STp, cmd, 0, DMA_NONE,
1240 STp->device->timeout, MAX_WRITE_RETRIES, 1);
1241 if (!SRpnt) {
1242 result = (STp->buffer)->syscall_result;
1243 goto out;
1244 }
1245
1246 if (STp->buffer->syscall_result == 0 ||
1247 (cmdstatp->have_sense && !cmdstatp->deferred &&
1248 (cmdstatp->flags & SENSE_EOM) &&
1249 (cmdstatp->sense_hdr.sense_key == NO_SENSE ||
1250 cmdstatp->sense_hdr.sense_key == RECOVERED_ERROR) &&
1251 (!cmdstatp->remainder_valid || cmdstatp->uremainder64 == 0))) {
1252 /* Write successful at EOM */
1253 st_release_request(SRpnt);
1254 SRpnt = NULL;
1255 if (STps->drv_file >= 0)
1256 STps->drv_file++;
1257 STps->drv_block = 0;
1258 if (STp->two_fm)
1259 cross_eof(STp, 0);
1260 STps->eof = ST_FM;
1261 }
1262 else { /* Write error */
1263 st_release_request(SRpnt);
1264 SRpnt = NULL;
1265 printk(KERN_ERR "%s: Error on write filemark.\n", name);
1266 if (result == 0)
1267 result = (-EIO);
1268 }
1269
1270 DEBC(printk(ST_DEB_MSG "%s: Buffer flushed, %d EOF(s) written\n",
1271 name, cmd[4]));
1272 } else if (!STp->rew_at_close) {
1273 STps = &(STp->ps[STp->partition]);
1274 if (!STm->sysv || STps->rw != ST_READING) {
1275 if (STp->can_bsr)
1276 result = flush_buffer(STp, 0);
1277 else if (STps->eof == ST_FM_HIT) {
1278 result = cross_eof(STp, 0);
1279 if (result) {
1280 if (STps->drv_file >= 0)
1281 STps->drv_file++;
1282 STps->drv_block = 0;
1283 STps->eof = ST_FM;
1284 } else
1285 STps->eof = ST_NOEOF;
1286 }
1287 } else if ((STps->eof == ST_NOEOF &&
1288 !(result = cross_eof(STp, 1))) ||
1289 STps->eof == ST_FM_HIT) {
1290 if (STps->drv_file >= 0)
1291 STps->drv_file++;
1292 STps->drv_block = 0;
1293 STps->eof = ST_FM;
1294 }
1295 }
1296
1297 out:
1298 if (STp->rew_at_close) {
1299 result2 = st_int_ioctl(STp, MTREW, 1);
1300 if (result == 0)
1301 result = result2;
1302 }
1303 return result;
1304 }
1305
1306
1307 /* Close the device and release it. BKL is not needed: this is the only thread
1308 accessing this tape. */
1309 static int st_release(struct inode *inode, struct file *filp)
1310 {
1311 int result = 0;
1312 struct scsi_tape *STp = filp->private_data;
1313
1314 if (STp->door_locked == ST_LOCKED_AUTO)
1315 do_door_lock(STp, 0);
1316
1317 normalize_buffer(STp->buffer);
1318 write_lock(&st_dev_arr_lock);
1319 STp->in_use = 0;
1320 write_unlock(&st_dev_arr_lock);
1321 scsi_tape_put(STp);
1322
1323 return result;
1324 }
1325 \f
1326 /* The checks common to both reading and writing */
1327 static ssize_t rw_checks(struct scsi_tape *STp, struct file *filp, size_t count)
1328 {
1329 ssize_t retval = 0;
1330
1331 /*
1332 * If we are in the middle of error recovery, don't let anyone
1333 * else try and use this device. Also, if error recovery fails, it
1334 * may try and take the device offline, in which case all further
1335 * access to the device is prohibited.
1336 */
1337 if (!scsi_block_when_processing_errors(STp->device)) {
1338 retval = (-ENXIO);
1339 goto out;
1340 }
1341
1342 if (STp->ready != ST_READY) {
1343 if (STp->ready == ST_NO_TAPE)
1344 retval = (-ENOMEDIUM);
1345 else
1346 retval = (-EIO);
1347 goto out;
1348 }
1349
1350 if (! STp->modes[STp->current_mode].defined) {
1351 retval = (-ENXIO);
1352 goto out;
1353 }
1354
1355
1356 /*
1357 * If there was a bus reset, block further access
1358 * to this device.
1359 */
1360 if (STp->pos_unknown) {
1361 retval = (-EIO);
1362 goto out;
1363 }
1364
1365 if (count == 0)
1366 goto out;
1367
1368 DEB(
1369 if (!STp->in_use) {
1370 printk(ST_DEB_MSG "%s: Incorrect device.\n", tape_name(STp));
1371 retval = (-EIO);
1372 goto out;
1373 } ) /* end DEB */
1374
1375 if (STp->can_partitions &&
1376 (retval = switch_partition(STp)) < 0)
1377 goto out;
1378
1379 if (STp->block_size == 0 && STp->max_block > 0 &&
1380 (count < STp->min_block || count > STp->max_block)) {
1381 retval = (-EINVAL);
1382 goto out;
1383 }
1384
1385 if (STp->do_auto_lock && STp->door_locked == ST_UNLOCKED &&
1386 !do_door_lock(STp, 1))
1387 STp->door_locked = ST_LOCKED_AUTO;
1388
1389 out:
1390 return retval;
1391 }
1392
1393
1394 static int setup_buffering(struct scsi_tape *STp, const char __user *buf,
1395 size_t count, int is_read)
1396 {
1397 int i, bufsize, retval = 0;
1398 struct st_buffer *STbp = STp->buffer;
1399
1400 if (is_read)
1401 i = STp->try_dio && try_rdio;
1402 else
1403 i = STp->try_dio && try_wdio;
1404
1405 if (i && ((unsigned long)buf & queue_dma_alignment(
1406 STp->device->request_queue)) == 0) {
1407 i = sgl_map_user_pages(&(STbp->sg[0]), STbp->use_sg,
1408 (unsigned long)buf, count, (is_read ? READ : WRITE));
1409 if (i > 0) {
1410 STbp->do_dio = i;
1411 STbp->buffer_bytes = 0; /* can be used as transfer counter */
1412 }
1413 else
1414 STbp->do_dio = 0; /* fall back to buffering with any error */
1415 STbp->sg_segs = STbp->do_dio;
1416 STbp->frp_sg_current = 0;
1417 DEB(
1418 if (STbp->do_dio) {
1419 STp->nbr_dio++;
1420 STp->nbr_pages += STbp->do_dio;
1421 for (i=1; i < STbp->do_dio; i++)
1422 if (page_to_pfn(STbp->sg[i].page) == page_to_pfn(STbp->sg[i-1].page) + 1)
1423 STp->nbr_combinable++;
1424 }
1425 )
1426 } else
1427 STbp->do_dio = 0;
1428 DEB( STp->nbr_requests++; )
1429
1430 if (!STbp->do_dio) {
1431 if (STp->block_size)
1432 bufsize = STp->block_size > st_fixed_buffer_size ?
1433 STp->block_size : st_fixed_buffer_size;
1434 else
1435 bufsize = count;
1436 if (bufsize > STbp->buffer_size &&
1437 !enlarge_buffer(STbp, bufsize, STp->restr_dma)) {
1438 printk(KERN_WARNING "%s: Can't allocate %d byte tape buffer.\n",
1439 tape_name(STp), bufsize);
1440 retval = (-EOVERFLOW);
1441 goto out;
1442 }
1443 if (STp->block_size)
1444 STbp->buffer_blocks = bufsize / STp->block_size;
1445 }
1446
1447 out:
1448 return retval;
1449 }
1450
1451
1452 /* Can be called more than once after each setup_buffer() */
1453 static void release_buffering(struct scsi_tape *STp, int is_read)
1454 {
1455 struct st_buffer *STbp;
1456
1457 STbp = STp->buffer;
1458 if (STbp->do_dio) {
1459 sgl_unmap_user_pages(&(STbp->sg[0]), STbp->do_dio, is_read);
1460 STbp->do_dio = 0;
1461 STbp->sg_segs = 0;
1462 }
1463 }
1464
1465
1466 /* Write command */
1467 static ssize_t
1468 st_write(struct file *filp, const char __user *buf, size_t count, loff_t * ppos)
1469 {
1470 ssize_t total;
1471 ssize_t i, do_count, blks, transfer;
1472 ssize_t retval;
1473 int undone, retry_eot = 0, scode;
1474 int async_write;
1475 unsigned char cmd[MAX_COMMAND_SIZE];
1476 const char __user *b_point;
1477 struct st_request *SRpnt = NULL;
1478 struct scsi_tape *STp = filp->private_data;
1479 struct st_modedef *STm;
1480 struct st_partstat *STps;
1481 struct st_buffer *STbp;
1482 char *name = tape_name(STp);
1483
1484 if (down_interruptible(&STp->lock))
1485 return -ERESTARTSYS;
1486
1487 retval = rw_checks(STp, filp, count);
1488 if (retval || count == 0)
1489 goto out;
1490
1491 /* Write must be integral number of blocks */
1492 if (STp->block_size != 0 && (count % STp->block_size) != 0) {
1493 printk(KERN_WARNING "%s: Write not multiple of tape block size.\n",
1494 name);
1495 retval = (-EINVAL);
1496 goto out;
1497 }
1498
1499 STm = &(STp->modes[STp->current_mode]);
1500 STps = &(STp->ps[STp->partition]);
1501
1502 if (STp->write_prot) {
1503 retval = (-EACCES);
1504 goto out;
1505 }
1506
1507
1508 if (STps->rw == ST_READING) {
1509 retval = flush_buffer(STp, 0);
1510 if (retval)
1511 goto out;
1512 STps->rw = ST_WRITING;
1513 } else if (STps->rw != ST_WRITING &&
1514 STps->drv_file == 0 && STps->drv_block == 0) {
1515 if ((retval = set_mode_densblk(STp, STm)) < 0)
1516 goto out;
1517 if (STm->default_compression != ST_DONT_TOUCH &&
1518 !(STp->compression_changed)) {
1519 if (st_compression(STp, (STm->default_compression == ST_YES))) {
1520 printk(KERN_WARNING "%s: Can't set default compression.\n",
1521 name);
1522 if (modes_defined) {
1523 retval = (-EINVAL);
1524 goto out;
1525 }
1526 }
1527 }
1528 }
1529
1530 STbp = STp->buffer;
1531 i = write_behind_check(STp);
1532 if (i) {
1533 if (i == -ENOSPC)
1534 STps->eof = ST_EOM_OK;
1535 else
1536 STps->eof = ST_EOM_ERROR;
1537 }
1538
1539 if (STps->eof == ST_EOM_OK) {
1540 STps->eof = ST_EOD_1; /* allow next write */
1541 retval = (-ENOSPC);
1542 goto out;
1543 }
1544 else if (STps->eof == ST_EOM_ERROR) {
1545 retval = (-EIO);
1546 goto out;
1547 }
1548
1549 /* Check the buffer readability in cases where copy_user might catch
1550 the problems after some tape movement. */
1551 if (STp->block_size != 0 &&
1552 !STbp->do_dio &&
1553 (copy_from_user(&i, buf, 1) != 0 ||
1554 copy_from_user(&i, buf + count - 1, 1) != 0)) {
1555 retval = (-EFAULT);
1556 goto out;
1557 }
1558
1559 retval = setup_buffering(STp, buf, count, 0);
1560 if (retval)
1561 goto out;
1562
1563 total = count;
1564
1565 memset(cmd, 0, MAX_COMMAND_SIZE);
1566 cmd[0] = WRITE_6;
1567 cmd[1] = (STp->block_size != 0);
1568
1569 STps->rw = ST_WRITING;
1570
1571 b_point = buf;
1572 while (count > 0 && !retry_eot) {
1573
1574 if (STbp->do_dio) {
1575 do_count = count;
1576 }
1577 else {
1578 if (STp->block_size == 0)
1579 do_count = count;
1580 else {
1581 do_count = STbp->buffer_blocks * STp->block_size -
1582 STbp->buffer_bytes;
1583 if (do_count > count)
1584 do_count = count;
1585 }
1586
1587 i = append_to_buffer(b_point, STbp, do_count);
1588 if (i) {
1589 retval = i;
1590 goto out;
1591 }
1592 }
1593 count -= do_count;
1594 b_point += do_count;
1595
1596 async_write = STp->block_size == 0 && !STbp->do_dio &&
1597 STm->do_async_writes && STps->eof < ST_EOM_OK;
1598
1599 if (STp->block_size != 0 && STm->do_buffer_writes &&
1600 !(STp->try_dio && try_wdio) && STps->eof < ST_EOM_OK &&
1601 STbp->buffer_bytes < STbp->buffer_size) {
1602 STp->dirty = 1;
1603 /* Don't write a buffer that is not full enough. */
1604 if (!async_write && count == 0)
1605 break;
1606 }
1607
1608 retry_write:
1609 if (STp->block_size == 0)
1610 blks = transfer = do_count;
1611 else {
1612 if (!STbp->do_dio)
1613 blks = STbp->buffer_bytes;
1614 else
1615 blks = do_count;
1616 blks /= STp->block_size;
1617 transfer = blks * STp->block_size;
1618 }
1619 cmd[2] = blks >> 16;
1620 cmd[3] = blks >> 8;
1621 cmd[4] = blks;
1622
1623 SRpnt = st_do_scsi(SRpnt, STp, cmd, transfer, DMA_TO_DEVICE,
1624 STp->device->timeout, MAX_WRITE_RETRIES, !async_write);
1625 if (!SRpnt) {
1626 retval = STbp->syscall_result;
1627 goto out;
1628 }
1629 if (async_write && !STbp->syscall_result) {
1630 STbp->writing = transfer;
1631 STp->dirty = !(STbp->writing ==
1632 STbp->buffer_bytes);
1633 SRpnt = NULL; /* Prevent releasing this request! */
1634 DEB( STp->write_pending = 1; )
1635 break;
1636 }
1637
1638 if (STbp->syscall_result != 0) {
1639 struct st_cmdstatus *cmdstatp = &STp->buffer->cmdstat;
1640
1641 DEBC(printk(ST_DEB_MSG "%s: Error on write:\n", name));
1642 if (cmdstatp->have_sense && (cmdstatp->flags & SENSE_EOM)) {
1643 scode = cmdstatp->sense_hdr.sense_key;
1644 if (cmdstatp->remainder_valid)
1645 undone = (int)cmdstatp->uremainder64;
1646 else if (STp->block_size == 0 &&
1647 scode == VOLUME_OVERFLOW)
1648 undone = transfer;
1649 else
1650 undone = 0;
1651 if (STp->block_size != 0)
1652 undone *= STp->block_size;
1653 if (undone <= do_count) {
1654 /* Only data from this write is not written */
1655 count += undone;
1656 do_count -= undone;
1657 if (STp->block_size)
1658 blks = (transfer - undone) / STp->block_size;
1659 STps->eof = ST_EOM_OK;
1660 /* Continue in fixed block mode if all written
1661 in this request but still something left to write
1662 (retval left to zero)
1663 */
1664 if (STp->block_size == 0 ||
1665 undone > 0 || count == 0)
1666 retval = (-ENOSPC); /* EOM within current request */
1667 DEBC(printk(ST_DEB_MSG
1668 "%s: EOM with %d bytes unwritten.\n",
1669 name, (int)count));
1670 } else {
1671 /* EOT within data buffered earlier (possible only
1672 in fixed block mode without direct i/o) */
1673 if (!retry_eot && !cmdstatp->deferred &&
1674 (scode == NO_SENSE || scode == RECOVERED_ERROR)) {
1675 move_buffer_data(STp->buffer, transfer - undone);
1676 retry_eot = 1;
1677 if (STps->drv_block >= 0) {
1678 STps->drv_block += (transfer - undone) /
1679 STp->block_size;
1680 }
1681 STps->eof = ST_EOM_OK;
1682 DEBC(printk(ST_DEB_MSG
1683 "%s: Retry write of %d bytes at EOM.\n",
1684 name, STp->buffer->buffer_bytes));
1685 goto retry_write;
1686 }
1687 else {
1688 /* Either error within data buffered by driver or
1689 failed retry */
1690 count -= do_count;
1691 blks = do_count = 0;
1692 STps->eof = ST_EOM_ERROR;
1693 STps->drv_block = (-1); /* Too cautious? */
1694 retval = (-EIO); /* EOM for old data */
1695 DEBC(printk(ST_DEB_MSG
1696 "%s: EOM with lost data.\n",
1697 name));
1698 }
1699 }
1700 } else {
1701 count += do_count;
1702 STps->drv_block = (-1); /* Too cautious? */
1703 retval = STbp->syscall_result;
1704 }
1705
1706 }
1707
1708 if (STps->drv_block >= 0) {
1709 if (STp->block_size == 0)
1710 STps->drv_block += (do_count > 0);
1711 else
1712 STps->drv_block += blks;
1713 }
1714
1715 STbp->buffer_bytes = 0;
1716 STp->dirty = 0;
1717
1718 if (retval || retry_eot) {
1719 if (count < total)
1720 retval = total - count;
1721 goto out;
1722 }
1723 }
1724
1725 if (STps->eof == ST_EOD_1)
1726 STps->eof = ST_EOM_OK;
1727 else if (STps->eof != ST_EOM_OK)
1728 STps->eof = ST_NOEOF;
1729 retval = total - count;
1730
1731 out:
1732 if (SRpnt != NULL)
1733 st_release_request(SRpnt);
1734 release_buffering(STp, 0);
1735 up(&STp->lock);
1736
1737 return retval;
1738 }
1739 \f
1740 /* Read data from the tape. Returns zero in the normal case, one if the
1741 eof status has changed, and the negative error code in case of a
1742 fatal error. Otherwise updates the buffer and the eof state.
1743
1744 Does release user buffer mapping if it is set.
1745 */
1746 static long read_tape(struct scsi_tape *STp, long count,
1747 struct st_request ** aSRpnt)
1748 {
1749 int transfer, blks, bytes;
1750 unsigned char cmd[MAX_COMMAND_SIZE];
1751 struct st_request *SRpnt;
1752 struct st_modedef *STm;
1753 struct st_partstat *STps;
1754 struct st_buffer *STbp;
1755 int retval = 0;
1756 char *name = tape_name(STp);
1757
1758 if (count == 0)
1759 return 0;
1760
1761 STm = &(STp->modes[STp->current_mode]);
1762 STps = &(STp->ps[STp->partition]);
1763 if (STps->eof == ST_FM_HIT)
1764 return 1;
1765 STbp = STp->buffer;
1766
1767 if (STp->block_size == 0)
1768 blks = bytes = count;
1769 else {
1770 if (!(STp->try_dio && try_rdio) && STm->do_read_ahead) {
1771 blks = (STp->buffer)->buffer_blocks;
1772 bytes = blks * STp->block_size;
1773 } else {
1774 bytes = count;
1775 if (!STbp->do_dio && bytes > (STp->buffer)->buffer_size)
1776 bytes = (STp->buffer)->buffer_size;
1777 blks = bytes / STp->block_size;
1778 bytes = blks * STp->block_size;
1779 }
1780 }
1781
1782 memset(cmd, 0, MAX_COMMAND_SIZE);
1783 cmd[0] = READ_6;
1784 cmd[1] = (STp->block_size != 0);
1785 cmd[2] = blks >> 16;
1786 cmd[3] = blks >> 8;
1787 cmd[4] = blks;
1788
1789 SRpnt = *aSRpnt;
1790 SRpnt = st_do_scsi(SRpnt, STp, cmd, bytes, DMA_FROM_DEVICE,
1791 STp->device->timeout, MAX_RETRIES, 1);
1792 release_buffering(STp, 1);
1793 *aSRpnt = SRpnt;
1794 if (!SRpnt)
1795 return STbp->syscall_result;
1796
1797 STbp->read_pointer = 0;
1798 STps->at_sm = 0;
1799
1800 /* Something to check */
1801 if (STbp->syscall_result) {
1802 struct st_cmdstatus *cmdstatp = &STp->buffer->cmdstat;
1803
1804 retval = 1;
1805 DEBC(printk(ST_DEB_MSG "%s: Sense: %2x %2x %2x %2x %2x %2x %2x %2x\n",
1806 name,
1807 SRpnt->sense[0], SRpnt->sense[1],
1808 SRpnt->sense[2], SRpnt->sense[3],
1809 SRpnt->sense[4], SRpnt->sense[5],
1810 SRpnt->sense[6], SRpnt->sense[7]));
1811 if (cmdstatp->have_sense) {
1812
1813 if (cmdstatp->sense_hdr.sense_key == BLANK_CHECK)
1814 cmdstatp->flags &= 0xcf; /* No need for EOM in this case */
1815
1816 if (cmdstatp->flags != 0) { /* EOF, EOM, or ILI */
1817 /* Compute the residual count */
1818 if (cmdstatp->remainder_valid)
1819 transfer = (int)cmdstatp->uremainder64;
1820 else
1821 transfer = 0;
1822 if (STp->block_size == 0 &&
1823 cmdstatp->sense_hdr.sense_key == MEDIUM_ERROR)
1824 transfer = bytes;
1825
1826 if (cmdstatp->flags & SENSE_ILI) { /* ILI */
1827 if (STp->block_size == 0) {
1828 if (transfer <= 0) {
1829 if (transfer < 0)
1830 printk(KERN_NOTICE
1831 "%s: Failed to read %d byte block with %d byte transfer.\n",
1832 name, bytes - transfer, bytes);
1833 if (STps->drv_block >= 0)
1834 STps->drv_block += 1;
1835 STbp->buffer_bytes = 0;
1836 return (-ENOMEM);
1837 }
1838 STbp->buffer_bytes = bytes - transfer;
1839 } else {
1840 st_release_request(SRpnt);
1841 SRpnt = *aSRpnt = NULL;
1842 if (transfer == blks) { /* We did not get anything, error */
1843 printk(KERN_NOTICE "%s: Incorrect block size.\n", name);
1844 if (STps->drv_block >= 0)
1845 STps->drv_block += blks - transfer + 1;
1846 st_int_ioctl(STp, MTBSR, 1);
1847 return (-EIO);
1848 }
1849 /* We have some data, deliver it */
1850 STbp->buffer_bytes = (blks - transfer) *
1851 STp->block_size;
1852 DEBC(printk(ST_DEB_MSG
1853 "%s: ILI but enough data received %ld %d.\n",
1854 name, count, STbp->buffer_bytes));
1855 if (STps->drv_block >= 0)
1856 STps->drv_block += 1;
1857 if (st_int_ioctl(STp, MTBSR, 1))
1858 return (-EIO);
1859 }
1860 } else if (cmdstatp->flags & SENSE_FMK) { /* FM overrides EOM */
1861 if (STps->eof != ST_FM_HIT)
1862 STps->eof = ST_FM_HIT;
1863 else
1864 STps->eof = ST_EOD_2;
1865 if (STp->block_size == 0)
1866 STbp->buffer_bytes = 0;
1867 else
1868 STbp->buffer_bytes =
1869 bytes - transfer * STp->block_size;
1870 DEBC(printk(ST_DEB_MSG
1871 "%s: EOF detected (%d bytes read).\n",
1872 name, STbp->buffer_bytes));
1873 } else if (cmdstatp->flags & SENSE_EOM) {
1874 if (STps->eof == ST_FM)
1875 STps->eof = ST_EOD_1;
1876 else
1877 STps->eof = ST_EOM_OK;
1878 if (STp->block_size == 0)
1879 STbp->buffer_bytes = bytes - transfer;
1880 else
1881 STbp->buffer_bytes =
1882 bytes - transfer * STp->block_size;
1883
1884 DEBC(printk(ST_DEB_MSG "%s: EOM detected (%d bytes read).\n",
1885 name, STbp->buffer_bytes));
1886 }
1887 }
1888 /* end of EOF, EOM, ILI test */
1889 else { /* nonzero sense key */
1890 DEBC(printk(ST_DEB_MSG
1891 "%s: Tape error while reading.\n", name));
1892 STps->drv_block = (-1);
1893 if (STps->eof == ST_FM &&
1894 cmdstatp->sense_hdr.sense_key == BLANK_CHECK) {
1895 DEBC(printk(ST_DEB_MSG
1896 "%s: Zero returned for first BLANK CHECK after EOF.\n",
1897 name));
1898 STps->eof = ST_EOD_2; /* First BLANK_CHECK after FM */
1899 } else /* Some other extended sense code */
1900 retval = (-EIO);
1901 }
1902
1903 if (STbp->buffer_bytes < 0) /* Caused by bogus sense data */
1904 STbp->buffer_bytes = 0;
1905 }
1906 /* End of extended sense test */
1907 else { /* Non-extended sense */
1908 retval = STbp->syscall_result;
1909 }
1910
1911 }
1912 /* End of error handling */
1913 else /* Read successful */
1914 STbp->buffer_bytes = bytes;
1915
1916 if (STps->drv_block >= 0) {
1917 if (STp->block_size == 0)
1918 STps->drv_block++;
1919 else
1920 STps->drv_block += STbp->buffer_bytes / STp->block_size;
1921 }
1922 return retval;
1923 }
1924 \f
1925
1926 /* Read command */
1927 static ssize_t
1928 st_read(struct file *filp, char __user *buf, size_t count, loff_t * ppos)
1929 {
1930 ssize_t total;
1931 ssize_t retval = 0;
1932 ssize_t i, transfer;
1933 int special, do_dio = 0;
1934 struct st_request *SRpnt = NULL;
1935 struct scsi_tape *STp = filp->private_data;
1936 struct st_modedef *STm;
1937 struct st_partstat *STps;
1938 struct st_buffer *STbp = STp->buffer;
1939 DEB( char *name = tape_name(STp); )
1940
1941 if (down_interruptible(&STp->lock))
1942 return -ERESTARTSYS;
1943
1944 retval = rw_checks(STp, filp, count);
1945 if (retval || count == 0)
1946 goto out;
1947
1948 STm = &(STp->modes[STp->current_mode]);
1949 if (!(STm->do_read_ahead) && STp->block_size != 0 &&
1950 (count % STp->block_size) != 0) {
1951 retval = (-EINVAL); /* Read must be integral number of blocks */
1952 goto out;
1953 }
1954
1955 STps = &(STp->ps[STp->partition]);
1956 if (STps->rw == ST_WRITING) {
1957 retval = flush_buffer(STp, 0);
1958 if (retval)
1959 goto out;
1960 STps->rw = ST_READING;
1961 }
1962 DEB(
1963 if (debugging && STps->eof != ST_NOEOF)
1964 printk(ST_DEB_MSG "%s: EOF/EOM flag up (%d). Bytes %d\n", name,
1965 STps->eof, STbp->buffer_bytes);
1966 ) /* end DEB */
1967
1968 retval = setup_buffering(STp, buf, count, 1);
1969 if (retval)
1970 goto out;
1971 do_dio = STbp->do_dio;
1972
1973 if (STbp->buffer_bytes == 0 &&
1974 STps->eof >= ST_EOD_1) {
1975 if (STps->eof < ST_EOD) {
1976 STps->eof += 1;
1977 retval = 0;
1978 goto out;
1979 }
1980 retval = (-EIO); /* EOM or Blank Check */
1981 goto out;
1982 }
1983
1984 if (do_dio) {
1985 /* Check the buffer writability before any tape movement. Don't alter
1986 buffer data. */
1987 if (copy_from_user(&i, buf, 1) != 0 ||
1988 copy_to_user(buf, &i, 1) != 0 ||
1989 copy_from_user(&i, buf + count - 1, 1) != 0 ||
1990 copy_to_user(buf + count - 1, &i, 1) != 0) {
1991 retval = (-EFAULT);
1992 goto out;
1993 }
1994 }
1995
1996 STps->rw = ST_READING;
1997
1998
1999 /* Loop until enough data in buffer or a special condition found */
2000 for (total = 0, special = 0; total < count && !special;) {
2001
2002 /* Get new data if the buffer is empty */
2003 if (STbp->buffer_bytes == 0) {
2004 special = read_tape(STp, count - total, &SRpnt);
2005 if (special < 0) { /* No need to continue read */
2006 retval = special;
2007 goto out;
2008 }
2009 }
2010
2011 /* Move the data from driver buffer to user buffer */
2012 if (STbp->buffer_bytes > 0) {
2013 DEB(
2014 if (debugging && STps->eof != ST_NOEOF)
2015 printk(ST_DEB_MSG
2016 "%s: EOF up (%d). Left %d, needed %d.\n", name,
2017 STps->eof, STbp->buffer_bytes,
2018 (int)(count - total));
2019 ) /* end DEB */
2020 transfer = STbp->buffer_bytes < count - total ?
2021 STbp->buffer_bytes : count - total;
2022 if (!do_dio) {
2023 i = from_buffer(STbp, buf, transfer);
2024 if (i) {
2025 retval = i;
2026 goto out;
2027 }
2028 }
2029 buf += transfer;
2030 total += transfer;
2031 }
2032
2033 if (STp->block_size == 0)
2034 break; /* Read only one variable length block */
2035
2036 } /* for (total = 0, special = 0;
2037 total < count && !special; ) */
2038
2039 /* Change the eof state if no data from tape or buffer */
2040 if (total == 0) {
2041 if (STps->eof == ST_FM_HIT) {
2042 STps->eof = ST_FM;
2043 STps->drv_block = 0;
2044 if (STps->drv_file >= 0)
2045 STps->drv_file++;
2046 } else if (STps->eof == ST_EOD_1) {
2047 STps->eof = ST_EOD_2;
2048 STps->drv_block = 0;
2049 if (STps->drv_file >= 0)
2050 STps->drv_file++;
2051 } else if (STps->eof == ST_EOD_2)
2052 STps->eof = ST_EOD;
2053 } else if (STps->eof == ST_FM)
2054 STps->eof = ST_NOEOF;
2055 retval = total;
2056
2057 out:
2058 if (SRpnt != NULL) {
2059 st_release_request(SRpnt);
2060 SRpnt = NULL;
2061 }
2062 if (do_dio) {
2063 release_buffering(STp, 1);
2064 STbp->buffer_bytes = 0;
2065 }
2066 up(&STp->lock);
2067
2068 return retval;
2069 }
2070 \f
2071
2072
2073 DEB(
2074 /* Set the driver options */
2075 static void st_log_options(struct scsi_tape * STp, struct st_modedef * STm, char *name)
2076 {
2077 if (debugging) {
2078 printk(KERN_INFO
2079 "%s: Mode %d options: buffer writes: %d, async writes: %d, read ahead: %d\n",
2080 name, STp->current_mode, STm->do_buffer_writes, STm->do_async_writes,
2081 STm->do_read_ahead);
2082 printk(KERN_INFO
2083 "%s: can bsr: %d, two FMs: %d, fast mteom: %d, auto lock: %d,\n",
2084 name, STp->can_bsr, STp->two_fm, STp->fast_mteom, STp->do_auto_lock);
2085 printk(KERN_INFO
2086 "%s: defs for wr: %d, no block limits: %d, partitions: %d, s2 log: %d\n",
2087 name, STm->defaults_for_writes, STp->omit_blklims, STp->can_partitions,
2088 STp->scsi2_logical);
2089 printk(KERN_INFO
2090 "%s: sysv: %d nowait: %d\n", name, STm->sysv, STp->immediate);
2091 printk(KERN_INFO "%s: debugging: %d\n",
2092 name, debugging);
2093 }
2094 }
2095 )
2096
2097
2098 static int st_set_options(struct scsi_tape *STp, long options)
2099 {
2100 int value;
2101 long code;
2102 struct st_modedef *STm;
2103 char *name = tape_name(STp);
2104 struct cdev *cd0, *cd1;
2105
2106 STm = &(STp->modes[STp->current_mode]);
2107 if (!STm->defined) {
2108 cd0 = STm->cdevs[0]; cd1 = STm->cdevs[1];
2109 memcpy(STm, &(STp->modes[0]), sizeof(struct st_modedef));
2110 STm->cdevs[0] = cd0; STm->cdevs[1] = cd1;
2111 modes_defined = 1;
2112 DEBC(printk(ST_DEB_MSG
2113 "%s: Initialized mode %d definition from mode 0\n",
2114 name, STp->current_mode));
2115 }
2116
2117 code = options & MT_ST_OPTIONS;
2118 if (code == MT_ST_BOOLEANS) {
2119 STm->do_buffer_writes = (options & MT_ST_BUFFER_WRITES) != 0;
2120 STm->do_async_writes = (options & MT_ST_ASYNC_WRITES) != 0;
2121 STm->defaults_for_writes = (options & MT_ST_DEF_WRITES) != 0;
2122 STm->do_read_ahead = (options & MT_ST_READ_AHEAD) != 0;
2123 STp->two_fm = (options & MT_ST_TWO_FM) != 0;
2124 STp->fast_mteom = (options & MT_ST_FAST_MTEOM) != 0;
2125 STp->do_auto_lock = (options & MT_ST_AUTO_LOCK) != 0;
2126 STp->can_bsr = (options & MT_ST_CAN_BSR) != 0;
2127 STp->omit_blklims = (options & MT_ST_NO_BLKLIMS) != 0;
2128 if ((STp->device)->scsi_level >= SCSI_2)
2129 STp->can_partitions = (options & MT_ST_CAN_PARTITIONS) != 0;
2130 STp->scsi2_logical = (options & MT_ST_SCSI2LOGICAL) != 0;
2131 STp->immediate = (options & MT_ST_NOWAIT) != 0;
2132 STm->sysv = (options & MT_ST_SYSV) != 0;
2133 DEB( debugging = (options & MT_ST_DEBUGGING) != 0;
2134 st_log_options(STp, STm, name); )
2135 } else if (code == MT_ST_SETBOOLEANS || code == MT_ST_CLEARBOOLEANS) {
2136 value = (code == MT_ST_SETBOOLEANS);
2137 if ((options & MT_ST_BUFFER_WRITES) != 0)
2138 STm->do_buffer_writes = value;
2139 if ((options & MT_ST_ASYNC_WRITES) != 0)
2140 STm->do_async_writes = value;
2141 if ((options & MT_ST_DEF_WRITES) != 0)
2142 STm->defaults_for_writes = value;
2143 if ((options & MT_ST_READ_AHEAD) != 0)
2144 STm->do_read_ahead = value;
2145 if ((options & MT_ST_TWO_FM) != 0)
2146 STp->two_fm = value;
2147 if ((options & MT_ST_FAST_MTEOM) != 0)
2148 STp->fast_mteom = value;
2149 if ((options & MT_ST_AUTO_LOCK) != 0)
2150 STp->do_auto_lock = value;
2151 if ((options & MT_ST_CAN_BSR) != 0)
2152 STp->can_bsr = value;
2153 if ((options & MT_ST_NO_BLKLIMS) != 0)
2154 STp->omit_blklims = value;
2155 if ((STp->device)->scsi_level >= SCSI_2 &&
2156 (options & MT_ST_CAN_PARTITIONS) != 0)
2157 STp->can_partitions = value;
2158 if ((options & MT_ST_SCSI2LOGICAL) != 0)
2159 STp->scsi2_logical = value;
2160 if ((options & MT_ST_NOWAIT) != 0)
2161 STp->immediate = value;
2162 if ((options & MT_ST_SYSV) != 0)
2163 STm->sysv = value;
2164 DEB(
2165 if ((options & MT_ST_DEBUGGING) != 0)
2166 debugging = value;
2167 st_log_options(STp, STm, name); )
2168 } else if (code == MT_ST_WRITE_THRESHOLD) {
2169 /* Retained for compatibility */
2170 } else if (code == MT_ST_DEF_BLKSIZE) {
2171 value = (options & ~MT_ST_OPTIONS);
2172 if (value == ~MT_ST_OPTIONS) {
2173 STm->default_blksize = (-1);
2174 DEBC( printk(KERN_INFO "%s: Default block size disabled.\n", name));
2175 } else {
2176 STm->default_blksize = value;
2177 DEBC( printk(KERN_INFO "%s: Default block size set to %d bytes.\n",
2178 name, STm->default_blksize));
2179 if (STp->ready == ST_READY) {
2180 STp->blksize_changed = 0;
2181 set_mode_densblk(STp, STm);
2182 }
2183 }
2184 } else if (code == MT_ST_TIMEOUTS) {
2185 value = (options & ~MT_ST_OPTIONS);
2186 if ((value & MT_ST_SET_LONG_TIMEOUT) != 0) {
2187 STp->long_timeout = (value & ~MT_ST_SET_LONG_TIMEOUT) * HZ;
2188 DEBC( printk(KERN_INFO "%s: Long timeout set to %d seconds.\n", name,
2189 (value & ~MT_ST_SET_LONG_TIMEOUT)));
2190 } else {
2191 STp->device->timeout = value * HZ;
2192 DEBC( printk(KERN_INFO "%s: Normal timeout set to %d seconds.\n",
2193 name, value) );
2194 }
2195 } else if (code == MT_ST_SET_CLN) {
2196 value = (options & ~MT_ST_OPTIONS) & 0xff;
2197 if (value != 0 &&
2198 value < EXTENDED_SENSE_START && value >= SCSI_SENSE_BUFFERSIZE)
2199 return (-EINVAL);
2200 STp->cln_mode = value;
2201 STp->cln_sense_mask = (options >> 8) & 0xff;
2202 STp->cln_sense_value = (options >> 16) & 0xff;
2203 printk(KERN_INFO
2204 "%s: Cleaning request mode %d, mask %02x, value %02x\n",
2205 name, value, STp->cln_sense_mask, STp->cln_sense_value);
2206 } else if (code == MT_ST_DEF_OPTIONS) {
2207 code = (options & ~MT_ST_CLEAR_DEFAULT);
2208 value = (options & MT_ST_CLEAR_DEFAULT);
2209 if (code == MT_ST_DEF_DENSITY) {
2210 if (value == MT_ST_CLEAR_DEFAULT) {
2211 STm->default_density = (-1);
2212 DEBC( printk(KERN_INFO "%s: Density default disabled.\n",
2213 name));
2214 } else {
2215 STm->default_density = value & 0xff;
2216 DEBC( printk(KERN_INFO "%s: Density default set to %x\n",
2217 name, STm->default_density));
2218 if (STp->ready == ST_READY) {
2219 STp->density_changed = 0;
2220 set_mode_densblk(STp, STm);
2221 }
2222 }
2223 } else if (code == MT_ST_DEF_DRVBUFFER) {
2224 if (value == MT_ST_CLEAR_DEFAULT) {
2225 STp->default_drvbuffer = 0xff;
2226 DEBC( printk(KERN_INFO
2227 "%s: Drive buffer default disabled.\n", name));
2228 } else {
2229 STp->default_drvbuffer = value & 7;
2230 DEBC( printk(KERN_INFO
2231 "%s: Drive buffer default set to %x\n",
2232 name, STp->default_drvbuffer));
2233 if (STp->ready == ST_READY)
2234 st_int_ioctl(STp, MTSETDRVBUFFER, STp->default_drvbuffer);
2235 }
2236 } else if (code == MT_ST_DEF_COMPRESSION) {
2237 if (value == MT_ST_CLEAR_DEFAULT) {
2238 STm->default_compression = ST_DONT_TOUCH;
2239 DEBC( printk(KERN_INFO
2240 "%s: Compression default disabled.\n", name));
2241 } else {
2242 if ((value & 0xff00) != 0) {
2243 STp->c_algo = (value & 0xff00) >> 8;
2244 DEBC( printk(KERN_INFO "%s: Compression algorithm set to 0x%x.\n",
2245 name, STp->c_algo));
2246 }
2247 if ((value & 0xff) != 0xff) {
2248 STm->default_compression = (value & 1 ? ST_YES : ST_NO);
2249 DEBC( printk(KERN_INFO "%s: Compression default set to %x\n",
2250 name, (value & 1)));
2251 if (STp->ready == ST_READY) {
2252 STp->compression_changed = 0;
2253 st_compression(STp, (STm->default_compression == ST_YES));
2254 }
2255 }
2256 }
2257 }
2258 } else
2259 return (-EIO);
2260
2261 return 0;
2262 }
2263 \f
2264 #define MODE_HEADER_LENGTH 4
2265
2266 /* Mode header and page byte offsets */
2267 #define MH_OFF_DATA_LENGTH 0
2268 #define MH_OFF_MEDIUM_TYPE 1
2269 #define MH_OFF_DEV_SPECIFIC 2
2270 #define MH_OFF_BDESCS_LENGTH 3
2271 #define MP_OFF_PAGE_NBR 0
2272 #define MP_OFF_PAGE_LENGTH 1
2273
2274 /* Mode header and page bit masks */
2275 #define MH_BIT_WP 0x80
2276 #define MP_MSK_PAGE_NBR 0x3f
2277
2278 /* Don't return block descriptors */
2279 #define MODE_SENSE_OMIT_BDESCS 0x08
2280
2281 #define MODE_SELECT_PAGE_FORMAT 0x10
2282
2283 /* Read a mode page into the tape buffer. The block descriptors are included
2284 if incl_block_descs is true. The page control is ored to the page number
2285 parameter, if necessary. */
2286 static int read_mode_page(struct scsi_tape *STp, int page, int omit_block_descs)
2287 {
2288 unsigned char cmd[MAX_COMMAND_SIZE];
2289 struct st_request *SRpnt = NULL;
2290
2291 memset(cmd, 0, MAX_COMMAND_SIZE);
2292 cmd[0] = MODE_SENSE;
2293 if (omit_block_descs)
2294 cmd[1] = MODE_SENSE_OMIT_BDESCS;
2295 cmd[2] = page;
2296 cmd[4] = 255;
2297
2298 SRpnt = st_do_scsi(SRpnt, STp, cmd, cmd[4], DMA_FROM_DEVICE,
2299 STp->device->timeout, 0, 1);
2300 if (SRpnt == NULL)
2301 return (STp->buffer)->syscall_result;
2302
2303 st_release_request(SRpnt);
2304
2305 return (STp->buffer)->syscall_result;
2306 }
2307
2308
2309 /* Send the mode page in the tape buffer to the drive. Assumes that the mode data
2310 in the buffer is correctly formatted. The long timeout is used if slow is non-zero. */
2311 static int write_mode_page(struct scsi_tape *STp, int page, int slow)
2312 {
2313 int pgo;
2314 unsigned char cmd[MAX_COMMAND_SIZE];
2315 struct st_request *SRpnt = NULL;
2316
2317 memset(cmd, 0, MAX_COMMAND_SIZE);
2318 cmd[0] = MODE_SELECT;
2319 cmd[1] = MODE_SELECT_PAGE_FORMAT;
2320 pgo = MODE_HEADER_LENGTH + (STp->buffer)->b_data[MH_OFF_BDESCS_LENGTH];
2321 cmd[4] = pgo + (STp->buffer)->b_data[pgo + MP_OFF_PAGE_LENGTH] + 2;
2322
2323 /* Clear reserved fields */
2324 (STp->buffer)->b_data[MH_OFF_DATA_LENGTH] = 0;
2325 (STp->buffer)->b_data[MH_OFF_MEDIUM_TYPE] = 0;
2326 (STp->buffer)->b_data[MH_OFF_DEV_SPECIFIC] &= ~MH_BIT_WP;
2327 (STp->buffer)->b_data[pgo + MP_OFF_PAGE_NBR] &= MP_MSK_PAGE_NBR;
2328
2329 SRpnt = st_do_scsi(SRpnt, STp, cmd, cmd[4], DMA_TO_DEVICE,
2330 (slow ? STp->long_timeout : STp->device->timeout), 0, 1);
2331 if (SRpnt == NULL)
2332 return (STp->buffer)->syscall_result;
2333
2334 st_release_request(SRpnt);
2335
2336 return (STp->buffer)->syscall_result;
2337 }
2338
2339
2340 #define COMPRESSION_PAGE 0x0f
2341 #define COMPRESSION_PAGE_LENGTH 16
2342
2343 #define CP_OFF_DCE_DCC 2
2344 #define CP_OFF_C_ALGO 7
2345
2346 #define DCE_MASK 0x80
2347 #define DCC_MASK 0x40
2348 #define RED_MASK 0x60
2349
2350
2351 /* Control the compression with mode page 15. Algorithm not changed if zero.
2352
2353 The block descriptors are read and written because Sony SDT-7000 does not
2354 work without this (suggestion from Michael Schaefer <Michael.Schaefer@dlr.de>).
2355 Including block descriptors should not cause any harm to other drives. */
2356
2357 static int st_compression(struct scsi_tape * STp, int state)
2358 {
2359 int retval;
2360 int mpoffs; /* Offset to mode page start */
2361 unsigned char *b_data = (STp->buffer)->b_data;
2362 DEB( char *name = tape_name(STp); )
2363
2364 if (STp->ready != ST_READY)
2365 return (-EIO);
2366
2367 /* Read the current page contents */
2368 retval = read_mode_page(STp, COMPRESSION_PAGE, 0);
2369 if (retval) {
2370 DEBC(printk(ST_DEB_MSG "%s: Compression mode page not supported.\n",
2371 name));
2372 return (-EIO);
2373 }
2374
2375 mpoffs = MODE_HEADER_LENGTH + b_data[MH_OFF_BDESCS_LENGTH];
2376 DEBC(printk(ST_DEB_MSG "%s: Compression state is %d.\n", name,
2377 (b_data[mpoffs + CP_OFF_DCE_DCC] & DCE_MASK ? 1 : 0)));
2378
2379 /* Check if compression can be changed */
2380 if ((b_data[mpoffs + CP_OFF_DCE_DCC] & DCC_MASK) == 0) {
2381 DEBC(printk(ST_DEB_MSG "%s: Compression not supported.\n", name));
2382 return (-EIO);
2383 }
2384
2385 /* Do the change */
2386 if (state) {
2387 b_data[mpoffs + CP_OFF_DCE_DCC] |= DCE_MASK;
2388 if (STp->c_algo != 0)
2389 b_data[mpoffs + CP_OFF_C_ALGO] = STp->c_algo;
2390 }
2391 else {
2392 b_data[mpoffs + CP_OFF_DCE_DCC] &= ~DCE_MASK;
2393 if (STp->c_algo != 0)
2394 b_data[mpoffs + CP_OFF_C_ALGO] = 0; /* no compression */
2395 }
2396
2397 retval = write_mode_page(STp, COMPRESSION_PAGE, 0);
2398 if (retval) {
2399 DEBC(printk(ST_DEB_MSG "%s: Compression change failed.\n", name));
2400 return (-EIO);
2401 }
2402 DEBC(printk(ST_DEB_MSG "%s: Compression state changed to %d.\n",
2403 name, state));
2404
2405 STp->compression_changed = 1;
2406 return 0;
2407 }
2408
2409
2410 /* Process the load and unload commands (does unload if the load code is zero) */
2411 static int do_load_unload(struct scsi_tape *STp, struct file *filp, int load_code)
2412 {
2413 int retval = (-EIO), timeout;
2414 DEB( char *name = tape_name(STp); )
2415 unsigned char cmd[MAX_COMMAND_SIZE];
2416 struct st_partstat *STps;
2417 struct st_request *SRpnt;
2418
2419 if (STp->ready != ST_READY && !load_code) {
2420 if (STp->ready == ST_NO_TAPE)
2421 return (-ENOMEDIUM);
2422 else
2423 return (-EIO);
2424 }
2425
2426 memset(cmd, 0, MAX_COMMAND_SIZE);
2427 cmd[0] = START_STOP;
2428 if (load_code)
2429 cmd[4] |= 1;
2430 /*
2431 * If arg >= 1 && arg <= 6 Enhanced load/unload in HP C1553A
2432 */
2433 if (load_code >= 1 + MT_ST_HPLOADER_OFFSET
2434 && load_code <= 6 + MT_ST_HPLOADER_OFFSET) {
2435 DEBC(printk(ST_DEB_MSG "%s: Enhanced %sload slot %2d.\n",
2436 name, (cmd[4]) ? "" : "un",
2437 load_code - MT_ST_HPLOADER_OFFSET));
2438 cmd[3] = load_code - MT_ST_HPLOADER_OFFSET; /* MediaID field of C1553A */
2439 }
2440 if (STp->immediate) {
2441 cmd[1] = 1; /* Don't wait for completion */
2442 timeout = STp->device->timeout;
2443 }
2444 else
2445 timeout = STp->long_timeout;
2446
2447 DEBC(
2448 if (!load_code)
2449 printk(ST_DEB_MSG "%s: Unloading tape.\n", name);
2450 else
2451 printk(ST_DEB_MSG "%s: Loading tape.\n", name);
2452 );
2453
2454 SRpnt = st_do_scsi(NULL, STp, cmd, 0, DMA_NONE,
2455 timeout, MAX_RETRIES, 1);
2456 if (!SRpnt)
2457 return (STp->buffer)->syscall_result;
2458
2459 retval = (STp->buffer)->syscall_result;
2460 st_release_request(SRpnt);
2461
2462 if (!retval) { /* SCSI command successful */
2463
2464 if (!load_code) {
2465 STp->rew_at_close = 0;
2466 STp->ready = ST_NO_TAPE;
2467 }
2468 else {
2469 STp->rew_at_close = STp->autorew_dev;
2470 retval = check_tape(STp, filp);
2471 if (retval > 0)
2472 retval = 0;
2473 }
2474 }
2475 else {
2476 STps = &(STp->ps[STp->partition]);
2477 STps->drv_file = STps->drv_block = (-1);
2478 }
2479
2480 return retval;
2481 }
2482 \f
2483 #if DEBUG
2484 #define ST_DEB_FORWARD 0
2485 #define ST_DEB_BACKWARD 1
2486 static void deb_space_print(char *name, int direction, char *units, unsigned char *cmd)
2487 {
2488 s32 sc;
2489
2490 sc = cmd[2] & 0x80 ? 0xff000000 : 0;
2491 sc |= (cmd[2] << 16) | (cmd[3] << 8) | cmd[4];
2492 if (direction)
2493 sc = -sc;
2494 printk(ST_DEB_MSG "%s: Spacing tape %s over %d %s.\n", name,
2495 direction ? "backward" : "forward", sc, units);
2496 }
2497 #endif
2498
2499
2500 /* Internal ioctl function */
2501 static int st_int_ioctl(struct scsi_tape *STp, unsigned int cmd_in, unsigned long arg)
2502 {
2503 int timeout;
2504 long ltmp;
2505 int ioctl_result;
2506 int chg_eof = 1;
2507 unsigned char cmd[MAX_COMMAND_SIZE];
2508 struct st_request *SRpnt;
2509 struct st_partstat *STps;
2510 int fileno, blkno, at_sm, undone;
2511 int datalen = 0, direction = DMA_NONE;
2512 char *name = tape_name(STp);
2513
2514 WARN_ON(STp->buffer->do_dio != 0);
2515 if (STp->ready != ST_READY) {
2516 if (STp->ready == ST_NO_TAPE)
2517 return (-ENOMEDIUM);
2518 else
2519 return (-EIO);
2520 }
2521 timeout = STp->long_timeout;
2522 STps = &(STp->ps[STp->partition]);
2523 fileno = STps->drv_file;
2524 blkno = STps->drv_block;
2525 at_sm = STps->at_sm;
2526
2527 memset(cmd, 0, MAX_COMMAND_SIZE);
2528 switch (cmd_in) {
2529 case MTFSFM:
2530 chg_eof = 0; /* Changed from the FSF after this */
2531 case MTFSF:
2532 cmd[0] = SPACE;
2533 cmd[1] = 0x01; /* Space FileMarks */
2534 cmd[2] = (arg >> 16);
2535 cmd[3] = (arg >> 8);
2536 cmd[4] = arg;
2537 DEBC(deb_space_print(name, ST_DEB_FORWARD, "filemarks", cmd);)
2538 if (fileno >= 0)
2539 fileno += arg;
2540 blkno = 0;
2541 at_sm &= (arg == 0);
2542 break;
2543 case MTBSFM:
2544 chg_eof = 0; /* Changed from the FSF after this */
2545 case MTBSF:
2546 cmd[0] = SPACE;
2547 cmd[1] = 0x01; /* Space FileMarks */
2548 ltmp = (-arg);
2549 cmd[2] = (ltmp >> 16);
2550 cmd[3] = (ltmp >> 8);
2551 cmd[4] = ltmp;
2552 DEBC(deb_space_print(name, ST_DEB_BACKWARD, "filemarks", cmd);)
2553 if (fileno >= 0)
2554 fileno -= arg;
2555 blkno = (-1); /* We can't know the block number */
2556 at_sm &= (arg == 0);
2557 break;
2558 case MTFSR:
2559 cmd[0] = SPACE;
2560 cmd[1] = 0x00; /* Space Blocks */
2561 cmd[2] = (arg >> 16);
2562 cmd[3] = (arg >> 8);
2563 cmd[4] = arg;
2564 DEBC(deb_space_print(name, ST_DEB_FORWARD, "blocks", cmd);)
2565 if (blkno >= 0)
2566 blkno += arg;
2567 at_sm &= (arg == 0);
2568 break;
2569 case MTBSR:
2570 cmd[0] = SPACE;
2571 cmd[1] = 0x00; /* Space Blocks */
2572 ltmp = (-arg);
2573 cmd[2] = (ltmp >> 16);
2574 cmd[3] = (ltmp >> 8);
2575 cmd[4] = ltmp;
2576 DEBC(deb_space_print(name, ST_DEB_BACKWARD, "blocks", cmd);)
2577 if (blkno >= 0)
2578 blkno -= arg;
2579 at_sm &= (arg == 0);
2580 break;
2581 case MTFSS:
2582 cmd[0] = SPACE;
2583 cmd[1] = 0x04; /* Space Setmarks */
2584 cmd[2] = (arg >> 16);
2585 cmd[3] = (arg >> 8);
2586 cmd[4] = arg;
2587 DEBC(deb_space_print(name, ST_DEB_FORWARD, "setmarks", cmd);)
2588 if (arg != 0) {
2589 blkno = fileno = (-1);
2590 at_sm = 1;
2591 }
2592 break;
2593 case MTBSS:
2594 cmd[0] = SPACE;
2595 cmd[1] = 0x04; /* Space Setmarks */
2596 ltmp = (-arg);
2597 cmd[2] = (ltmp >> 16);
2598 cmd[3] = (ltmp >> 8);
2599 cmd[4] = ltmp;
2600 DEBC(deb_space_print(name, ST_DEB_BACKWARD, "setmarks", cmd);)
2601 if (arg != 0) {
2602 blkno = fileno = (-1);
2603 at_sm = 1;
2604 }
2605 break;
2606 case MTWEOF:
2607 case MTWSM:
2608 if (STp->write_prot)
2609 return (-EACCES);
2610 cmd[0] = WRITE_FILEMARKS;
2611 if (cmd_in == MTWSM)
2612 cmd[1] = 2;
2613 cmd[2] = (arg >> 16);
2614 cmd[3] = (arg >> 8);
2615 cmd[4] = arg;
2616 timeout = STp->device->timeout;
2617 DEBC(
2618 if (cmd_in == MTWEOF)
2619 printk(ST_DEB_MSG "%s: Writing %d filemarks.\n", name,
2620 cmd[2] * 65536 + cmd[3] * 256 + cmd[4]);
2621 else
2622 printk(ST_DEB_MSG "%s: Writing %d setmarks.\n", name,
2623 cmd[2] * 65536 + cmd[3] * 256 + cmd[4]);
2624 )
2625 if (fileno >= 0)
2626 fileno += arg;
2627 blkno = 0;
2628 at_sm = (cmd_in == MTWSM);
2629 break;
2630 case MTREW:
2631 cmd[0] = REZERO_UNIT;
2632 if (STp->immediate) {
2633 cmd[1] = 1; /* Don't wait for completion */
2634 timeout = STp->device->timeout;
2635 }
2636 DEBC(printk(ST_DEB_MSG "%s: Rewinding tape.\n", name));
2637 fileno = blkno = at_sm = 0;
2638 break;
2639 case MTNOP:
2640 DEBC(printk(ST_DEB_MSG "%s: No op on tape.\n", name));
2641 return 0; /* Should do something ? */
2642 break;
2643 case MTRETEN:
2644 cmd[0] = START_STOP;
2645 if (STp->immediate) {
2646 cmd[1] = 1; /* Don't wait for completion */
2647 timeout = STp->device->timeout;
2648 }
2649 cmd[4] = 3;
2650 DEBC(printk(ST_DEB_MSG "%s: Retensioning tape.\n", name));
2651 fileno = blkno = at_sm = 0;
2652 break;
2653 case MTEOM:
2654 if (!STp->fast_mteom) {
2655 /* space to the end of tape */
2656 ioctl_result = st_int_ioctl(STp, MTFSF, 0x7fffff);
2657 fileno = STps->drv_file;
2658 if (STps->eof >= ST_EOD_1)
2659 return 0;
2660 /* The next lines would hide the number of spaced FileMarks
2661 That's why I inserted the previous lines. I had no luck
2662 with detecting EOM with FSF, so we go now to EOM.
2663 Joerg Weule */
2664 } else
2665 fileno = (-1);
2666 cmd[0] = SPACE;
2667 cmd[1] = 3;
2668 DEBC(printk(ST_DEB_MSG "%s: Spacing to end of recorded medium.\n",
2669 name));
2670 blkno = -1;
2671 at_sm = 0;
2672 break;
2673 case MTERASE:
2674 if (STp->write_prot)
2675 return (-EACCES);
2676 cmd[0] = ERASE;
2677 cmd[1] = (arg ? 1 : 0); /* Long erase with non-zero argument */
2678 if (STp->immediate) {
2679 cmd[1] |= 2; /* Don't wait for completion */
2680 timeout = STp->device->timeout;
2681 }
2682 else
2683 timeout = STp->long_timeout * 8;
2684
2685 DEBC(printk(ST_DEB_MSG "%s: Erasing tape.\n", name));
2686 fileno = blkno = at_sm = 0;
2687 break;
2688 case MTSETBLK: /* Set block length */
2689 case MTSETDENSITY: /* Set tape density */
2690 case MTSETDRVBUFFER: /* Set drive buffering */
2691 case SET_DENS_AND_BLK: /* Set density and block size */
2692 chg_eof = 0;
2693 if (STp->dirty || (STp->buffer)->buffer_bytes != 0)
2694 return (-EIO); /* Not allowed if data in buffer */
2695 if ((cmd_in == MTSETBLK || cmd_in == SET_DENS_AND_BLK) &&
2696 (arg & MT_ST_BLKSIZE_MASK) != 0 &&
2697 STp->max_block > 0 &&
2698 ((arg & MT_ST_BLKSIZE_MASK) < STp->min_block ||
2699 (arg & MT_ST_BLKSIZE_MASK) > STp->max_block)) {
2700 printk(KERN_WARNING "%s: Illegal block size.\n", name);
2701 return (-EINVAL);
2702 }
2703 cmd[0] = MODE_SELECT;
2704 if ((STp->use_pf & USE_PF))
2705 cmd[1] = MODE_SELECT_PAGE_FORMAT;
2706 cmd[4] = datalen = 12;
2707 direction = DMA_TO_DEVICE;
2708
2709 memset((STp->buffer)->b_data, 0, 12);
2710 if (cmd_in == MTSETDRVBUFFER)
2711 (STp->buffer)->b_data[2] = (arg & 7) << 4;
2712 else
2713 (STp->buffer)->b_data[2] =
2714 STp->drv_buffer << 4;
2715 (STp->buffer)->b_data[3] = 8; /* block descriptor length */
2716 if (cmd_in == MTSETDENSITY) {
2717 (STp->buffer)->b_data[4] = arg;
2718 STp->density_changed = 1; /* At least we tried ;-) */
2719 } else if (cmd_in == SET_DENS_AND_BLK)
2720 (STp->buffer)->b_data[4] = arg >> 24;
2721 else
2722 (STp->buffer)->b_data[4] = STp->density;
2723 if (cmd_in == MTSETBLK || cmd_in == SET_DENS_AND_BLK) {
2724 ltmp = arg & MT_ST_BLKSIZE_MASK;
2725 if (cmd_in == MTSETBLK)
2726 STp->blksize_changed = 1; /* At least we tried ;-) */
2727 } else
2728 ltmp = STp->block_size;
2729 (STp->buffer)->b_data[9] = (ltmp >> 16);
2730 (STp->buffer)->b_data[10] = (ltmp >> 8);
2731 (STp->buffer)->b_data[11] = ltmp;
2732 timeout = STp->device->timeout;
2733 DEBC(
2734 if (cmd_in == MTSETBLK || cmd_in == SET_DENS_AND_BLK)
2735 printk(ST_DEB_MSG
2736 "%s: Setting block size to %d bytes.\n", name,
2737 (STp->buffer)->b_data[9] * 65536 +
2738 (STp->buffer)->b_data[10] * 256 +
2739 (STp->buffer)->b_data[11]);
2740 if (cmd_in == MTSETDENSITY || cmd_in == SET_DENS_AND_BLK)
2741 printk(ST_DEB_MSG
2742 "%s: Setting density code to %x.\n", name,
2743 (STp->buffer)->b_data[4]);
2744 if (cmd_in == MTSETDRVBUFFER)
2745 printk(ST_DEB_MSG
2746 "%s: Setting drive buffer code to %d.\n", name,
2747 ((STp->buffer)->b_data[2] >> 4) & 7);
2748 )
2749 break;
2750 default:
2751 return (-ENOSYS);
2752 }
2753
2754 SRpnt = st_do_scsi(NULL, STp, cmd, datalen, direction,
2755 timeout, MAX_RETRIES, 1);
2756 if (!SRpnt)
2757 return (STp->buffer)->syscall_result;
2758
2759 ioctl_result = (STp->buffer)->syscall_result;
2760
2761 if (!ioctl_result) { /* SCSI command successful */
2762 st_release_request(SRpnt);
2763 SRpnt = NULL;
2764 STps->drv_block = blkno;
2765 STps->drv_file = fileno;
2766 STps->at_sm = at_sm;
2767
2768 if (cmd_in == MTBSFM)
2769 ioctl_result = st_int_ioctl(STp, MTFSF, 1);
2770 else if (cmd_in == MTFSFM)
2771 ioctl_result = st_int_ioctl(STp, MTBSF, 1);
2772
2773 if (cmd_in == MTSETBLK || cmd_in == SET_DENS_AND_BLK) {
2774 int old_block_size = STp->block_size;
2775 STp->block_size = arg & MT_ST_BLKSIZE_MASK;
2776 if (STp->block_size != 0) {
2777 if (old_block_size == 0)
2778 normalize_buffer(STp->buffer);
2779 (STp->buffer)->buffer_blocks =
2780 (STp->buffer)->buffer_size / STp->block_size;
2781 }
2782 (STp->buffer)->buffer_bytes = (STp->buffer)->read_pointer = 0;
2783 if (cmd_in == SET_DENS_AND_BLK)
2784 STp->density = arg >> MT_ST_DENSITY_SHIFT;
2785 } else if (cmd_in == MTSETDRVBUFFER)
2786 STp->drv_buffer = (arg & 7);
2787 else if (cmd_in == MTSETDENSITY)
2788 STp->density = arg;
2789
2790 if (cmd_in == MTEOM)
2791 STps->eof = ST_EOD;
2792 else if (cmd_in == MTFSF)
2793 STps->eof = ST_FM;
2794 else if (chg_eof)
2795 STps->eof = ST_NOEOF;
2796
2797 if (cmd_in == MTWEOF)
2798 STps->rw = ST_IDLE;
2799 } else { /* SCSI command was not completely successful. Don't return
2800 from this block without releasing the SCSI command block! */
2801 struct st_cmdstatus *cmdstatp = &STp->buffer->cmdstat;
2802
2803 if (cmdstatp->flags & SENSE_EOM) {
2804 if (cmd_in != MTBSF && cmd_in != MTBSFM &&
2805 cmd_in != MTBSR && cmd_in != MTBSS)
2806 STps->eof = ST_EOM_OK;
2807 STps->drv_block = 0;
2808 }
2809
2810 if (cmdstatp->remainder_valid)
2811 undone = (int)cmdstatp->uremainder64;
2812 else
2813 undone = 0;
2814
2815 if (cmd_in == MTWEOF &&
2816 cmdstatp->have_sense &&
2817 (cmdstatp->flags & SENSE_EOM) &&
2818 (cmdstatp->sense_hdr.sense_key == NO_SENSE ||
2819 cmdstatp->sense_hdr.sense_key == RECOVERED_ERROR) &&
2820 undone == 0) {
2821 ioctl_result = 0; /* EOF written succesfully at EOM */
2822 if (fileno >= 0)
2823 fileno++;
2824 STps->drv_file = fileno;
2825 STps->eof = ST_NOEOF;
2826 } else if ((cmd_in == MTFSF) || (cmd_in == MTFSFM)) {
2827 if (fileno >= 0)
2828 STps->drv_file = fileno - undone;
2829 else
2830 STps->drv_file = fileno;
2831 STps->drv_block = -1;
2832 STps->eof = ST_NOEOF;
2833 } else if ((cmd_in == MTBSF) || (cmd_in == MTBSFM)) {
2834 if (arg > 0 && undone < 0) /* Some drives get this wrong */
2835 undone = (-undone);
2836 if (STps->drv_file >= 0)
2837 STps->drv_file = fileno + undone;
2838 STps->drv_block = 0;
2839 STps->eof = ST_NOEOF;
2840 } else if (cmd_in == MTFSR) {
2841 if (cmdstatp->flags & SENSE_FMK) { /* Hit filemark */
2842 if (STps->drv_file >= 0)
2843 STps->drv_file++;
2844 STps->drv_block = 0;
2845 STps->eof = ST_FM;
2846 } else {
2847 if (blkno >= undone)
2848 STps->drv_block = blkno - undone;
2849 else
2850 STps->drv_block = (-1);
2851 STps->eof = ST_NOEOF;
2852 }
2853 } else if (cmd_in == MTBSR) {
2854 if (cmdstatp->flags & SENSE_FMK) { /* Hit filemark */
2855 STps->drv_file--;
2856 STps->drv_block = (-1);
2857 } else {
2858 if (arg > 0 && undone < 0) /* Some drives get this wrong */
2859 undone = (-undone);
2860 if (STps->drv_block >= 0)
2861 STps->drv_block = blkno + undone;
2862 }
2863 STps->eof = ST_NOEOF;
2864 } else if (cmd_in == MTEOM) {
2865 STps->drv_file = (-1);
2866 STps->drv_block = (-1);
2867 STps->eof = ST_EOD;
2868 } else if (cmd_in == MTSETBLK ||
2869 cmd_in == MTSETDENSITY ||
2870 cmd_in == MTSETDRVBUFFER ||
2871 cmd_in == SET_DENS_AND_BLK) {
2872 if (cmdstatp->sense_hdr.sense_key == ILLEGAL_REQUEST &&
2873 !(STp->use_pf & PF_TESTED)) {
2874 /* Try the other possible state of Page Format if not
2875 already tried */
2876 STp->use_pf = !STp->use_pf | PF_TESTED;
2877 st_release_request(SRpnt);
2878 SRpnt = NULL;
2879 return st_int_ioctl(STp, cmd_in, arg);
2880 }
2881 } else if (chg_eof)
2882 STps->eof = ST_NOEOF;
2883
2884 if (cmdstatp->sense_hdr.sense_key == BLANK_CHECK)
2885 STps->eof = ST_EOD;
2886
2887 st_release_request(SRpnt);
2888 SRpnt = NULL;
2889 }
2890
2891 return ioctl_result;
2892 }
2893 \f
2894
2895 /* Get the tape position. If bt == 2, arg points into a kernel space mt_loc
2896 structure. */
2897
2898 static int get_location(struct scsi_tape *STp, unsigned int *block, int *partition,
2899 int logical)
2900 {
2901 int result;
2902 unsigned char scmd[MAX_COMMAND_SIZE];
2903 struct st_request *SRpnt;
2904 DEB( char *name = tape_name(STp); )
2905
2906 if (STp->ready != ST_READY)
2907 return (-EIO);
2908
2909 memset(scmd, 0, MAX_COMMAND_SIZE);
2910 if ((STp->device)->scsi_level < SCSI_2) {
2911 scmd[0] = QFA_REQUEST_BLOCK;
2912 scmd[4] = 3;
2913 } else {
2914 scmd[0] = READ_POSITION;
2915 if (!logical && !STp->scsi2_logical)
2916 scmd[1] = 1;
2917 }
2918 SRpnt = st_do_scsi(NULL, STp, scmd, 20, DMA_FROM_DEVICE,
2919 STp->device->timeout, MAX_READY_RETRIES, 1);
2920 if (!SRpnt)
2921 return (STp->buffer)->syscall_result;
2922
2923 if ((STp->buffer)->syscall_result != 0 ||
2924 (STp->device->scsi_level >= SCSI_2 &&
2925 ((STp->buffer)->b_data[0] & 4) != 0)) {
2926 *block = *partition = 0;
2927 DEBC(printk(ST_DEB_MSG "%s: Can't read tape position.\n", name));
2928 result = (-EIO);
2929 } else {
2930 result = 0;
2931 if ((STp->device)->scsi_level < SCSI_2) {
2932 *block = ((STp->buffer)->b_data[0] << 16)
2933 + ((STp->buffer)->b_data[1] << 8)
2934 + (STp->buffer)->b_data[2];
2935 *partition = 0;
2936 } else {
2937 *block = ((STp->buffer)->b_data[4] << 24)
2938 + ((STp->buffer)->b_data[5] << 16)
2939 + ((STp->buffer)->b_data[6] << 8)
2940 + (STp->buffer)->b_data[7];
2941 *partition = (STp->buffer)->b_data[1];
2942 if (((STp->buffer)->b_data[0] & 0x80) &&
2943 (STp->buffer)->b_data[1] == 0) /* BOP of partition 0 */
2944 STp->ps[0].drv_block = STp->ps[0].drv_file = 0;
2945 }
2946 DEBC(printk(ST_DEB_MSG "%s: Got tape pos. blk %d part %d.\n", name,
2947 *block, *partition));
2948 }
2949 st_release_request(SRpnt);
2950 SRpnt = NULL;
2951
2952 return result;
2953 }
2954
2955
2956 /* Set the tape block and partition. Negative partition means that only the
2957 block should be set in vendor specific way. */
2958 static int set_location(struct scsi_tape *STp, unsigned int block, int partition,
2959 int logical)
2960 {
2961 struct st_partstat *STps;
2962 int result, p;
2963 unsigned int blk;
2964 int timeout;
2965 unsigned char scmd[MAX_COMMAND_SIZE];
2966 struct st_request *SRpnt;
2967 DEB( char *name = tape_name(STp); )
2968
2969 if (STp->ready != ST_READY)
2970 return (-EIO);
2971 timeout = STp->long_timeout;
2972 STps = &(STp->ps[STp->partition]);
2973
2974 DEBC(printk(ST_DEB_MSG "%s: Setting block to %d and partition to %d.\n",
2975 name, block, partition));
2976 DEB(if (partition < 0)
2977 return (-EIO); )
2978
2979 /* Update the location at the partition we are leaving */
2980 if ((!STp->can_partitions && partition != 0) ||
2981 partition >= ST_NBR_PARTITIONS)
2982 return (-EINVAL);
2983 if (partition != STp->partition) {
2984 if (get_location(STp, &blk, &p, 1))
2985 STps->last_block_valid = 0;
2986 else {
2987 STps->last_block_valid = 1;
2988 STps->last_block_visited = blk;
2989 DEBC(printk(ST_DEB_MSG
2990 "%s: Visited block %d for partition %d saved.\n",
2991 name, blk, STp->partition));
2992 }
2993 }
2994
2995 memset(scmd, 0, MAX_COMMAND_SIZE);
2996 if ((STp->device)->scsi_level < SCSI_2) {
2997 scmd[0] = QFA_SEEK_BLOCK;
2998 scmd[2] = (block >> 16);
2999 scmd[3] = (block >> 8);
3000 scmd[4] = block;
3001 scmd[5] = 0;
3002 } else {
3003 scmd[0] = SEEK_10;
3004 scmd[3] = (block >> 24);
3005 scmd[4] = (block >> 16);
3006 scmd[5] = (block >> 8);
3007 scmd[6] = block;
3008 if (!logical && !STp->scsi2_logical)
3009 scmd[1] = 4;
3010 if (STp->partition != partition) {
3011 scmd[1] |= 2;
3012 scmd[8] = partition;
3013 DEBC(printk(ST_DEB_MSG
3014 "%s: Trying to change partition from %d to %d\n",
3015 name, STp->partition, partition));
3016 }
3017 }
3018 if (STp->immediate) {
3019 scmd[1] |= 1; /* Don't wait for completion */
3020 timeout = STp->device->timeout;
3021 }
3022
3023 SRpnt = st_do_scsi(NULL, STp, scmd, 0, DMA_NONE,
3024 timeout, MAX_READY_RETRIES, 1);
3025 if (!SRpnt)
3026 return (STp->buffer)->syscall_result;
3027
3028 STps->drv_block = STps->drv_file = (-1);
3029 STps->eof = ST_NOEOF;
3030 if ((STp->buffer)->syscall_result != 0) {
3031 result = (-EIO);
3032 if (STp->can_partitions &&
3033 (STp->device)->scsi_level >= SCSI_2 &&
3034 (p = find_partition(STp)) >= 0)
3035 STp->partition = p;
3036 } else {
3037 if (STp->can_partitions) {
3038 STp->partition = partition;
3039 STps = &(STp->ps[partition]);
3040 if (!STps->last_block_valid ||
3041 STps->last_block_visited != block) {
3042 STps->at_sm = 0;
3043 STps->rw = ST_IDLE;
3044 }
3045 } else
3046 STps->at_sm = 0;
3047 if (block == 0)
3048 STps->drv_block = STps->drv_file = 0;
3049 result = 0;
3050 }
3051
3052 st_release_request(SRpnt);
3053 SRpnt = NULL;
3054
3055 return result;
3056 }
3057
3058
3059 /* Find the current partition number for the drive status. Called from open and
3060 returns either partition number of negative error code. */
3061 static int find_partition(struct scsi_tape *STp)
3062 {
3063 int i, partition;
3064 unsigned int block;
3065
3066 if ((i = get_location(STp, &block, &partition, 1)) < 0)
3067 return i;
3068 if (partition >= ST_NBR_PARTITIONS)
3069 return (-EIO);
3070 return partition;
3071 }
3072
3073
3074 /* Change the partition if necessary */
3075 static int switch_partition(struct scsi_tape *STp)
3076 {
3077 struct st_partstat *STps;
3078
3079 if (STp->partition == STp->new_partition)
3080 return 0;
3081 STps = &(STp->ps[STp->new_partition]);
3082 if (!STps->last_block_valid)
3083 STps->last_block_visited = 0;
3084 return set_location(STp, STps->last_block_visited, STp->new_partition, 1);
3085 }
3086 \f
3087 /* Functions for reading and writing the medium partition mode page. */
3088
3089 #define PART_PAGE 0x11
3090 #define PART_PAGE_FIXED_LENGTH 8
3091
3092 #define PP_OFF_MAX_ADD_PARTS 2
3093 #define PP_OFF_NBR_ADD_PARTS 3
3094 #define PP_OFF_FLAGS 4
3095 #define PP_OFF_PART_UNITS 6
3096 #define PP_OFF_RESERVED 7
3097
3098 #define PP_BIT_IDP 0x20
3099 #define PP_MSK_PSUM_MB 0x10
3100
3101 /* Get the number of partitions on the tape. As a side effect reads the
3102 mode page into the tape buffer. */
3103 static int nbr_partitions(struct scsi_tape *STp)
3104 {
3105 int result;
3106 DEB( char *name = tape_name(STp); )
3107
3108 if (STp->ready != ST_READY)
3109 return (-EIO);
3110
3111 result = read_mode_page(STp, PART_PAGE, 1);
3112
3113 if (result) {
3114 DEBC(printk(ST_DEB_MSG "%s: Can't read medium partition page.\n",
3115 name));
3116 result = (-EIO);
3117 } else {
3118 result = (STp->buffer)->b_data[MODE_HEADER_LENGTH +
3119 PP_OFF_NBR_ADD_PARTS] + 1;
3120 DEBC(printk(ST_DEB_MSG "%s: Number of partitions %d.\n", name, result));
3121 }
3122
3123 return result;
3124 }
3125
3126
3127 /* Partition the tape into two partitions if size > 0 or one partition if
3128 size == 0.
3129
3130 The block descriptors are read and written because Sony SDT-7000 does not
3131 work without this (suggestion from Michael Schaefer <Michael.Schaefer@dlr.de>).
3132
3133 My HP C1533A drive returns only one partition size field. This is used to
3134 set the size of partition 1. There is no size field for the default partition.
3135 Michael Schaefer's Sony SDT-7000 returns two descriptors and the second is
3136 used to set the size of partition 1 (this is what the SCSI-3 standard specifies).
3137 The following algorithm is used to accommodate both drives: if the number of
3138 partition size fields is greater than the maximum number of additional partitions
3139 in the mode page, the second field is used. Otherwise the first field is used.
3140
3141 For Seagate DDS drives the page length must be 8 when no partitions is defined
3142 and 10 when 1 partition is defined (information from Eric Lee Green). This is
3143 is acceptable also to some other old drives and enforced if the first partition
3144 size field is used for the first additional partition size.
3145 */
3146 static int partition_tape(struct scsi_tape *STp, int size)
3147 {
3148 char *name = tape_name(STp);
3149 int result;
3150 int pgo, psd_cnt, psdo;
3151 unsigned char *bp;
3152
3153 result = read_mode_page(STp, PART_PAGE, 0);
3154 if (result) {
3155 DEBC(printk(ST_DEB_MSG "%s: Can't read partition mode page.\n", name));
3156 return result;
3157 }
3158 /* The mode page is in the buffer. Let's modify it and write it. */
3159 bp = (STp->buffer)->b_data;
3160 pgo = MODE_HEADER_LENGTH + bp[MH_OFF_BDESCS_LENGTH];
3161 DEBC(printk(ST_DEB_MSG "%s: Partition page length is %d bytes.\n",
3162 name, bp[pgo + MP_OFF_PAGE_LENGTH] + 2));
3163
3164 psd_cnt = (bp[pgo + MP_OFF_PAGE_LENGTH] + 2 - PART_PAGE_FIXED_LENGTH) / 2;
3165 psdo = pgo + PART_PAGE_FIXED_LENGTH;
3166 if (psd_cnt > bp[pgo + PP_OFF_MAX_ADD_PARTS]) {
3167 bp[psdo] = bp[psdo + 1] = 0xff; /* Rest of the tape */
3168 psdo += 2;
3169 }
3170 memset(bp + psdo, 0, bp[pgo + PP_OFF_NBR_ADD_PARTS] * 2);
3171
3172 DEBC(printk("%s: psd_cnt %d, max.parts %d, nbr_parts %d\n", name,
3173 psd_cnt, bp[pgo + PP_OFF_MAX_ADD_PARTS],
3174 bp[pgo + PP_OFF_NBR_ADD_PARTS]));
3175
3176 if (size <= 0) {
3177 bp[pgo + PP_OFF_NBR_ADD_PARTS] = 0;
3178 if (psd_cnt <= bp[pgo + PP_OFF_MAX_ADD_PARTS])
3179 bp[pgo + MP_OFF_PAGE_LENGTH] = 6;
3180 DEBC(printk(ST_DEB_MSG "%s: Formatting tape with one partition.\n",
3181 name));
3182 } else {
3183 bp[psdo] = (size >> 8) & 0xff;
3184 bp[psdo + 1] = size & 0xff;
3185 bp[pgo + 3] = 1;
3186 if (bp[pgo + MP_OFF_PAGE_LENGTH] < 8)
3187 bp[pgo + MP_OFF_PAGE_LENGTH] = 8;
3188 DEBC(printk(ST_DEB_MSG
3189 "%s: Formatting tape with two partitions (1 = %d MB).\n",
3190 name, size));
3191 }
3192 bp[pgo + PP_OFF_PART_UNITS] = 0;
3193 bp[pgo + PP_OFF_RESERVED] = 0;
3194 bp[pgo + PP_OFF_FLAGS] = PP_BIT_IDP | PP_MSK_PSUM_MB;
3195
3196 result = write_mode_page(STp, PART_PAGE, 1);
3197 if (result) {
3198 printk(KERN_INFO "%s: Partitioning of tape failed.\n", name);
3199 result = (-EIO);
3200 }
3201
3202 return result;
3203 }
3204 \f
3205
3206
3207 /* The ioctl command */
3208 static int st_ioctl(struct inode *inode, struct file *file,
3209 unsigned int cmd_in, unsigned long arg)
3210 {
3211 int i, cmd_nr, cmd_type, bt;
3212 int retval = 0;
3213 unsigned int blk;
3214 struct scsi_tape *STp = file->private_data;
3215 struct st_modedef *STm;
3216 struct st_partstat *STps;
3217 char *name = tape_name(STp);
3218 void __user *p = (void __user *)arg;
3219
3220 if (down_interruptible(&STp->lock))
3221 return -ERESTARTSYS;
3222
3223 DEB(
3224 if (debugging && !STp->in_use) {
3225 printk(ST_DEB_MSG "%s: Incorrect device.\n", name);
3226 retval = (-EIO);
3227 goto out;
3228 } ) /* end DEB */
3229
3230 STm = &(STp->modes[STp->current_mode]);
3231 STps = &(STp->ps[STp->partition]);
3232
3233 /*
3234 * If we are in the middle of error recovery, don't let anyone
3235 * else try and use this device. Also, if error recovery fails, it
3236 * may try and take the device offline, in which case all further
3237 * access to the device is prohibited.
3238 */
3239 retval = scsi_nonblockable_ioctl(STp->device, cmd_in, p, file);
3240 if (!scsi_block_when_processing_errors(STp->device) || retval != -ENODEV)
3241 goto out;
3242 retval = 0;
3243
3244 cmd_type = _IOC_TYPE(cmd_in);
3245 cmd_nr = _IOC_NR(cmd_in);
3246
3247 if (cmd_type == _IOC_TYPE(MTIOCTOP) && cmd_nr == _IOC_NR(MTIOCTOP)) {
3248 struct mtop mtc;
3249
3250 if (_IOC_SIZE(cmd_in) != sizeof(mtc)) {
3251 retval = (-EINVAL);
3252 goto out;
3253 }
3254
3255 i = copy_from_user(&mtc, p, sizeof(struct mtop));
3256 if (i) {
3257 retval = (-EFAULT);
3258 goto out;
3259 }
3260
3261 if (mtc.mt_op == MTSETDRVBUFFER && !capable(CAP_SYS_ADMIN)) {
3262 printk(KERN_WARNING
3263 "%s: MTSETDRVBUFFER only allowed for root.\n", name);
3264 retval = (-EPERM);
3265 goto out;
3266 }
3267 if (!STm->defined &&
3268 (mtc.mt_op != MTSETDRVBUFFER &&
3269 (mtc.mt_count & MT_ST_OPTIONS) == 0)) {
3270 retval = (-ENXIO);
3271 goto out;
3272 }
3273
3274 if (!STp->pos_unknown) {
3275
3276 if (STps->eof == ST_FM_HIT) {
3277 if (mtc.mt_op == MTFSF || mtc.mt_op == MTFSFM ||
3278 mtc.mt_op == MTEOM) {
3279 mtc.mt_count -= 1;
3280 if (STps->drv_file >= 0)
3281 STps->drv_file += 1;
3282 } else if (mtc.mt_op == MTBSF || mtc.mt_op == MTBSFM) {
3283 mtc.mt_count += 1;
3284 if (STps->drv_file >= 0)
3285 STps->drv_file += 1;
3286 }
3287 }
3288
3289 if (mtc.mt_op == MTSEEK) {
3290 /* Old position must be restored if partition will be
3291 changed */
3292 i = !STp->can_partitions ||
3293 (STp->new_partition != STp->partition);
3294 } else {
3295 i = mtc.mt_op == MTREW || mtc.mt_op == MTOFFL ||
3296 mtc.mt_op == MTRETEN || mtc.mt_op == MTEOM ||
3297 mtc.mt_op == MTLOCK || mtc.mt_op == MTLOAD ||
3298 mtc.mt_op == MTFSF || mtc.mt_op == MTFSFM ||
3299 mtc.mt_op == MTBSF || mtc.mt_op == MTBSFM ||
3300 mtc.mt_op == MTCOMPRESSION;
3301 }
3302 i = flush_buffer(STp, i);
3303 if (i < 0) {
3304 retval = i;
3305 goto out;
3306 }
3307 if (STps->rw == ST_WRITING &&
3308 (mtc.mt_op == MTREW || mtc.mt_op == MTOFFL ||
3309 mtc.mt_op == MTSEEK ||
3310 mtc.mt_op == MTBSF || mtc.mt_op == MTBSFM)) {
3311 i = st_int_ioctl(STp, MTWEOF, 1);
3312 if (i < 0) {
3313 retval = i;
3314 goto out;
3315 }
3316 if (mtc.mt_op == MTBSF || mtc.mt_op == MTBSFM)
3317 mtc.mt_count++;
3318 STps->rw = ST_IDLE;
3319 }
3320
3321 } else {
3322 /*
3323 * If there was a bus reset, block further access
3324 * to this device. If the user wants to rewind the tape,
3325 * then reset the flag and allow access again.
3326 */
3327 if (mtc.mt_op != MTREW &&
3328 mtc.mt_op != MTOFFL &&
3329 mtc.mt_op != MTRETEN &&
3330 mtc.mt_op != MTERASE &&
3331 mtc.mt_op != MTSEEK &&
3332 mtc.mt_op != MTEOM) {
3333 retval = (-EIO);
3334 goto out;
3335 }
3336 reset_state(STp);
3337 /* remove this when the midlevel properly clears was_reset */
3338 STp->device->was_reset = 0;
3339 }
3340
3341 if (mtc.mt_op != MTNOP && mtc.mt_op != MTSETBLK &&
3342 mtc.mt_op != MTSETDENSITY && mtc.mt_op != MTWSM &&
3343 mtc.mt_op != MTSETDRVBUFFER && mtc.mt_op != MTSETPART)
3344 STps->rw = ST_IDLE; /* Prevent automatic WEOF and fsf */
3345
3346 if (mtc.mt_op == MTOFFL && STp->door_locked != ST_UNLOCKED)
3347 do_door_lock(STp, 0); /* Ignore result! */
3348
3349 if (mtc.mt_op == MTSETDRVBUFFER &&
3350 (mtc.mt_count & MT_ST_OPTIONS) != 0) {
3351 retval = st_set_options(STp, mtc.mt_count);
3352 goto out;
3353 }
3354
3355 if (mtc.mt_op == MTSETPART) {
3356 if (!STp->can_partitions ||
3357 mtc.mt_count < 0 || mtc.mt_count >= ST_NBR_PARTITIONS) {
3358 retval = (-EINVAL);
3359 goto out;
3360 }
3361 if (mtc.mt_count >= STp->nbr_partitions &&
3362 (STp->nbr_partitions = nbr_partitions(STp)) < 0) {
3363 retval = (-EIO);
3364 goto out;
3365 }
3366 if (mtc.mt_count >= STp->nbr_partitions) {
3367 retval = (-EINVAL);
3368 goto out;
3369 }
3370 STp->new_partition = mtc.mt_count;
3371 retval = 0;
3372 goto out;
3373 }
3374
3375 if (mtc.mt_op == MTMKPART) {
3376 if (!STp->can_partitions) {
3377 retval = (-EINVAL);
3378 goto out;
3379 }
3380 if ((i = st_int_ioctl(STp, MTREW, 0)) < 0 ||
3381 (i = partition_tape(STp, mtc.mt_count)) < 0) {
3382 retval = i;
3383 goto out;
3384 }
3385 for (i = 0; i < ST_NBR_PARTITIONS; i++) {
3386 STp->ps[i].rw = ST_IDLE;
3387 STp->ps[i].at_sm = 0;
3388 STp->ps[i].last_block_valid = 0;
3389 }
3390 STp->partition = STp->new_partition = 0;
3391 STp->nbr_partitions = 1; /* Bad guess ?-) */
3392 STps->drv_block = STps->drv_file = 0;
3393 retval = 0;
3394 goto out;
3395 }
3396
3397 if (mtc.mt_op == MTSEEK) {
3398 i = set_location(STp, mtc.mt_count, STp->new_partition, 0);
3399 if (!STp->can_partitions)
3400 STp->ps[0].rw = ST_IDLE;
3401 retval = i;
3402 goto out;
3403 }
3404
3405 if (mtc.mt_op == MTUNLOAD || mtc.mt_op == MTOFFL) {
3406 retval = do_load_unload(STp, file, 0);
3407 goto out;
3408 }
3409
3410 if (mtc.mt_op == MTLOAD) {
3411 retval = do_load_unload(STp, file, max(1, mtc.mt_count));
3412 goto out;
3413 }
3414
3415 if (mtc.mt_op == MTLOCK || mtc.mt_op == MTUNLOCK) {
3416 retval = do_door_lock(STp, (mtc.mt_op == MTLOCK));
3417 goto out;
3418 }
3419
3420 if (STp->can_partitions && STp->ready == ST_READY &&
3421 (i = switch_partition(STp)) < 0) {
3422 retval = i;
3423 goto out;
3424 }
3425
3426 if (mtc.mt_op == MTCOMPRESSION)
3427 retval = st_compression(STp, (mtc.mt_count & 1));
3428 else
3429 retval = st_int_ioctl(STp, mtc.mt_op, mtc.mt_count);
3430 goto out;
3431 }
3432 if (!STm->defined) {
3433 retval = (-ENXIO);
3434 goto out;
3435 }
3436
3437 if ((i = flush_buffer(STp, 0)) < 0) {
3438 retval = i;
3439 goto out;
3440 }
3441 if (STp->can_partitions &&
3442 (i = switch_partition(STp)) < 0) {
3443 retval = i;
3444 goto out;
3445 }
3446
3447 if (cmd_type == _IOC_TYPE(MTIOCGET) && cmd_nr == _IOC_NR(MTIOCGET)) {
3448 struct mtget mt_status;
3449
3450 if (_IOC_SIZE(cmd_in) != sizeof(struct mtget)) {
3451 retval = (-EINVAL);
3452 goto out;
3453 }
3454
3455 mt_status.mt_type = STp->tape_type;
3456 mt_status.mt_dsreg =
3457 ((STp->block_size << MT_ST_BLKSIZE_SHIFT) & MT_ST_BLKSIZE_MASK) |
3458 ((STp->density << MT_ST_DENSITY_SHIFT) & MT_ST_DENSITY_MASK);
3459 mt_status.mt_blkno = STps->drv_block;
3460 mt_status.mt_fileno = STps->drv_file;
3461 if (STp->block_size != 0) {
3462 if (STps->rw == ST_WRITING)
3463 mt_status.mt_blkno +=
3464 (STp->buffer)->buffer_bytes / STp->block_size;
3465 else if (STps->rw == ST_READING)
3466 mt_status.mt_blkno -=
3467 ((STp->buffer)->buffer_bytes +
3468 STp->block_size - 1) / STp->block_size;
3469 }
3470
3471 mt_status.mt_gstat = 0;
3472 if (STp->drv_write_prot)
3473 mt_status.mt_gstat |= GMT_WR_PROT(0xffffffff);
3474 if (mt_status.mt_blkno == 0) {
3475 if (mt_status.mt_fileno == 0)
3476 mt_status.mt_gstat |= GMT_BOT(0xffffffff);
3477 else
3478 mt_status.mt_gstat |= GMT_EOF(0xffffffff);
3479 }
3480 mt_status.mt_erreg = (STp->recover_reg << MT_ST_SOFTERR_SHIFT);
3481 mt_status.mt_resid = STp->partition;
3482 if (STps->eof == ST_EOM_OK || STps->eof == ST_EOM_ERROR)
3483 mt_status.mt_gstat |= GMT_EOT(0xffffffff);
3484 else if (STps->eof >= ST_EOM_OK)
3485 mt_status.mt_gstat |= GMT_EOD(0xffffffff);
3486 if (STp->density == 1)
3487 mt_status.mt_gstat |= GMT_D_800(0xffffffff);
3488 else if (STp->density == 2)
3489 mt_status.mt_gstat |= GMT_D_1600(0xffffffff);
3490 else if (STp->density == 3)
3491 mt_status.mt_gstat |= GMT_D_6250(0xffffffff);
3492 if (STp->ready == ST_READY)
3493 mt_status.mt_gstat |= GMT_ONLINE(0xffffffff);
3494 if (STp->ready == ST_NO_TAPE)
3495 mt_status.mt_gstat |= GMT_DR_OPEN(0xffffffff);
3496 if (STps->at_sm)
3497 mt_status.mt_gstat |= GMT_SM(0xffffffff);
3498 if (STm->do_async_writes ||
3499 (STm->do_buffer_writes && STp->block_size != 0) ||
3500 STp->drv_buffer != 0)
3501 mt_status.mt_gstat |= GMT_IM_REP_EN(0xffffffff);
3502 if (STp->cleaning_req)
3503 mt_status.mt_gstat |= GMT_CLN(0xffffffff);
3504
3505 i = copy_to_user(p, &mt_status, sizeof(struct mtget));
3506 if (i) {
3507 retval = (-EFAULT);
3508 goto out;
3509 }
3510
3511 STp->recover_reg = 0; /* Clear after read */
3512 retval = 0;
3513 goto out;
3514 } /* End of MTIOCGET */
3515 if (cmd_type == _IOC_TYPE(MTIOCPOS) && cmd_nr == _IOC_NR(MTIOCPOS)) {
3516 struct mtpos mt_pos;
3517 if (_IOC_SIZE(cmd_in) != sizeof(struct mtpos)) {
3518 retval = (-EINVAL);
3519 goto out;
3520 }
3521 if ((i = get_location(STp, &blk, &bt, 0)) < 0) {
3522 retval = i;
3523 goto out;
3524 }
3525 mt_pos.mt_blkno = blk;
3526 i = copy_to_user(p, &mt_pos, sizeof(struct mtpos));
3527 if (i)
3528 retval = (-EFAULT);
3529 goto out;
3530 }
3531 up(&STp->lock);
3532 switch (cmd_in) {
3533 case SCSI_IOCTL_GET_IDLUN:
3534 case SCSI_IOCTL_GET_BUS_NUMBER:
3535 break;
3536 default:
3537 if ((cmd_in == SG_IO ||
3538 cmd_in == SCSI_IOCTL_SEND_COMMAND ||
3539 cmd_in == CDROM_SEND_PACKET) &&
3540 !capable(CAP_SYS_RAWIO))
3541 i = -EPERM;
3542 else
3543 i = scsi_cmd_ioctl(file, STp->disk, cmd_in, p);
3544 if (i != -ENOTTY)
3545 return i;
3546 break;
3547 }
3548 retval = scsi_ioctl(STp->device, cmd_in, p);
3549 if (!retval && cmd_in == SCSI_IOCTL_STOP_UNIT) { /* unload */
3550 STp->rew_at_close = 0;
3551 STp->ready = ST_NO_TAPE;
3552 }
3553 return retval;
3554
3555 out:
3556 up(&STp->lock);
3557 return retval;
3558 }
3559
3560 #ifdef CONFIG_COMPAT
3561 static long st_compat_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
3562 {
3563 struct scsi_tape *STp = file->private_data;
3564 struct scsi_device *sdev = STp->device;
3565 int ret = -ENOIOCTLCMD;
3566 if (sdev->host->hostt->compat_ioctl) {
3567
3568 ret = sdev->host->hostt->compat_ioctl(sdev, cmd, (void __user *)arg);
3569
3570 }
3571 return ret;
3572 }
3573 #endif
3574
3575 \f
3576
3577 /* Try to allocate a new tape buffer. Calling function must not hold
3578 dev_arr_lock. */
3579 static struct st_buffer *
3580 new_tape_buffer(int from_initialization, int need_dma, int max_sg)
3581 {
3582 int i, got = 0;
3583 gfp_t priority;
3584 struct st_buffer *tb;
3585
3586 if (from_initialization)
3587 priority = GFP_ATOMIC;
3588 else
3589 priority = GFP_KERNEL;
3590
3591 i = sizeof(struct st_buffer) + (max_sg - 1) * sizeof(struct scatterlist) +
3592 max_sg * sizeof(struct st_buf_fragment);
3593 tb = kzalloc(i, priority);
3594 if (!tb) {
3595 printk(KERN_NOTICE "st: Can't allocate new tape buffer.\n");
3596 return NULL;
3597 }
3598 tb->frp_segs = tb->orig_frp_segs = 0;
3599 tb->use_sg = max_sg;
3600 tb->frp = (struct st_buf_fragment *)(&(tb->sg[0]) + max_sg);
3601
3602 tb->in_use = 1;
3603 tb->dma = need_dma;
3604 tb->buffer_size = got;
3605
3606 return tb;
3607 }
3608
3609
3610 /* Try to allocate enough space in the tape buffer */
3611 static int enlarge_buffer(struct st_buffer * STbuffer, int new_size, int need_dma)
3612 {
3613 int segs, nbr, max_segs, b_size, order, got;
3614 gfp_t priority;
3615
3616 if (new_size <= STbuffer->buffer_size)
3617 return 1;
3618
3619 if (STbuffer->buffer_size <= PAGE_SIZE)
3620 normalize_buffer(STbuffer); /* Avoid extra segment */
3621
3622 max_segs = STbuffer->use_sg;
3623 nbr = max_segs - STbuffer->frp_segs;
3624 if (nbr <= 0)
3625 return 0;
3626
3627 priority = GFP_KERNEL | __GFP_NOWARN;
3628 if (need_dma)
3629 priority |= GFP_DMA;
3630 for (b_size = PAGE_SIZE, order=0; order <= 6 &&
3631 b_size < new_size - STbuffer->buffer_size;
3632 order++, b_size *= 2)
3633 ; /* empty */
3634
3635 for (segs = STbuffer->frp_segs, got = STbuffer->buffer_size;
3636 segs < max_segs && got < new_size;) {
3637 STbuffer->frp[segs].page = alloc_pages(priority, order);
3638 if (STbuffer->frp[segs].page == NULL) {
3639 if (new_size - got <= (max_segs - segs) * b_size / 2) {
3640 b_size /= 2; /* Large enough for the rest of the buffers */
3641 order--;
3642 continue;
3643 }
3644 DEB(STbuffer->buffer_size = got);
3645 normalize_buffer(STbuffer);
3646 return 0;
3647 }
3648 STbuffer->frp[segs].length = b_size;
3649 STbuffer->frp_segs += 1;
3650 got += b_size;
3651 STbuffer->buffer_size = got;
3652 segs++;
3653 }
3654 STbuffer->b_data = page_address(STbuffer->frp[0].page);
3655
3656 return 1;
3657 }
3658
3659
3660 /* Release the extra buffer */
3661 static void normalize_buffer(struct st_buffer * STbuffer)
3662 {
3663 int i, order;
3664
3665 for (i = STbuffer->orig_frp_segs; i < STbuffer->frp_segs; i++) {
3666 order = get_order(STbuffer->frp[i].length);
3667 __free_pages(STbuffer->frp[i].page, order);
3668 STbuffer->buffer_size -= STbuffer->frp[i].length;
3669 }
3670 STbuffer->frp_segs = STbuffer->orig_frp_segs;
3671 STbuffer->frp_sg_current = 0;
3672 STbuffer->sg_segs = 0;
3673 }
3674
3675
3676 /* Move data from the user buffer to the tape buffer. Returns zero (success) or
3677 negative error code. */
3678 static int append_to_buffer(const char __user *ubp, struct st_buffer * st_bp, int do_count)
3679 {
3680 int i, cnt, res, offset;
3681
3682 for (i = 0, offset = st_bp->buffer_bytes;
3683 i < st_bp->frp_segs && offset >= st_bp->frp[i].length; i++)
3684 offset -= st_bp->frp[i].length;
3685 if (i == st_bp->frp_segs) { /* Should never happen */
3686 printk(KERN_WARNING "st: append_to_buffer offset overflow.\n");
3687 return (-EIO);
3688 }
3689 for (; i < st_bp->frp_segs && do_count > 0; i++) {
3690 cnt = st_bp->frp[i].length - offset < do_count ?
3691 st_bp->frp[i].length - offset : do_count;
3692 res = copy_from_user(page_address(st_bp->frp[i].page) + offset, ubp, cnt);
3693 if (res)
3694 return (-EFAULT);
3695 do_count -= cnt;
3696 st_bp->buffer_bytes += cnt;
3697 ubp += cnt;
3698 offset = 0;
3699 }
3700 if (do_count) /* Should never happen */
3701 return (-EIO);
3702
3703 return 0;
3704 }
3705
3706
3707 /* Move data from the tape buffer to the user buffer. Returns zero (success) or
3708 negative error code. */
3709 static int from_buffer(struct st_buffer * st_bp, char __user *ubp, int do_count)
3710 {
3711 int i, cnt, res, offset;
3712
3713 for (i = 0, offset = st_bp->read_pointer;
3714 i < st_bp->frp_segs && offset >= st_bp->frp[i].length; i++)
3715 offset -= st_bp->frp[i].length;
3716 if (i == st_bp->frp_segs) { /* Should never happen */
3717 printk(KERN_WARNING "st: from_buffer offset overflow.\n");
3718 return (-EIO);
3719 }
3720 for (; i < st_bp->frp_segs && do_count > 0; i++) {
3721 cnt = st_bp->frp[i].length - offset < do_count ?
3722 st_bp->frp[i].length - offset : do_count;
3723 res = copy_to_user(ubp, page_address(st_bp->frp[i].page) + offset, cnt);
3724 if (res)
3725 return (-EFAULT);
3726 do_count -= cnt;
3727 st_bp->buffer_bytes -= cnt;
3728 st_bp->read_pointer += cnt;
3729 ubp += cnt;
3730 offset = 0;
3731 }
3732 if (do_count) /* Should never happen */
3733 return (-EIO);
3734
3735 return 0;
3736 }
3737
3738
3739 /* Move data towards start of buffer */
3740 static void move_buffer_data(struct st_buffer * st_bp, int offset)
3741 {
3742 int src_seg, dst_seg, src_offset = 0, dst_offset;
3743 int count, total;
3744
3745 if (offset == 0)
3746 return;
3747
3748 total=st_bp->buffer_bytes - offset;
3749 for (src_seg=0; src_seg < st_bp->frp_segs; src_seg++) {
3750 src_offset = offset;
3751 if (src_offset < st_bp->frp[src_seg].length)
3752 break;
3753 offset -= st_bp->frp[src_seg].length;
3754 }
3755
3756 st_bp->buffer_bytes = st_bp->read_pointer = total;
3757 for (dst_seg=dst_offset=0; total > 0; ) {
3758 count = min(st_bp->frp[dst_seg].length - dst_offset,
3759 st_bp->frp[src_seg].length - src_offset);
3760 memmove(page_address(st_bp->frp[dst_seg].page) + dst_offset,
3761 page_address(st_bp->frp[src_seg].page) + src_offset, count);
3762 src_offset += count;
3763 if (src_offset >= st_bp->frp[src_seg].length) {
3764 src_seg++;
3765 src_offset = 0;
3766 }
3767 dst_offset += count;
3768 if (dst_offset >= st_bp->frp[dst_seg].length) {
3769 dst_seg++;
3770 dst_offset = 0;
3771 }
3772 total -= count;
3773 }
3774 }
3775
3776
3777 /* Fill the s/g list up to the length required for this transfer */
3778 static void buf_to_sg(struct st_buffer *STbp, unsigned int length)
3779 {
3780 int i;
3781 unsigned int count;
3782 struct scatterlist *sg;
3783 struct st_buf_fragment *frp;
3784
3785 if (length == STbp->frp_sg_current)
3786 return; /* work already done */
3787
3788 sg = &(STbp->sg[0]);
3789 frp = STbp->frp;
3790 for (i=count=0; count < length; i++) {
3791 sg[i].page = frp[i].page;
3792 if (length - count > frp[i].length)
3793 sg[i].length = frp[i].length;
3794 else
3795 sg[i].length = length - count;
3796 count += sg[i].length;
3797 sg[i].offset = 0;
3798 }
3799 STbp->sg_segs = i;
3800 STbp->frp_sg_current = length;
3801 }
3802
3803
3804 /* Validate the options from command line or module parameters */
3805 static void validate_options(void)
3806 {
3807 if (buffer_kbs > 0)
3808 st_fixed_buffer_size = buffer_kbs * ST_KILOBYTE;
3809 if (max_sg_segs >= ST_FIRST_SG)
3810 st_max_sg_segs = max_sg_segs;
3811 }
3812
3813 #ifndef MODULE
3814 /* Set the boot options. Syntax is defined in Documenation/scsi/st.txt.
3815 */
3816 static int __init st_setup(char *str)
3817 {
3818 int i, len, ints[5];
3819 char *stp;
3820
3821 stp = get_options(str, ARRAY_SIZE(ints), ints);
3822
3823 if (ints[0] > 0) {
3824 for (i = 0; i < ints[0] && i < ARRAY_SIZE(parms); i++)
3825 if (parms[i].val)
3826 *parms[i].val = ints[i + 1];
3827 } else {
3828 while (stp != NULL) {
3829 for (i = 0; i < ARRAY_SIZE(parms); i++) {
3830 len = strlen(parms[i].name);
3831 if (!strncmp(stp, parms[i].name, len) &&
3832 (*(stp + len) == ':' || *(stp + len) == '=')) {
3833 if (parms[i].val)
3834 *parms[i].val =
3835 simple_strtoul(stp + len + 1, NULL, 0);
3836 else
3837 printk(KERN_WARNING "st: Obsolete parameter %s\n",
3838 parms[i].name);
3839 break;
3840 }
3841 }
3842 if (i >= sizeof(parms) / sizeof(struct st_dev_parm))
3843 printk(KERN_WARNING "st: invalid parameter in '%s'\n",
3844 stp);
3845 stp = strchr(stp, ',');
3846 if (stp)
3847 stp++;
3848 }
3849 }
3850
3851 validate_options();
3852
3853 return 1;
3854 }
3855
3856 __setup("st=", st_setup);
3857
3858 #endif
3859
3860 static struct file_operations st_fops =
3861 {
3862 .owner = THIS_MODULE,
3863 .read = st_read,
3864 .write = st_write,
3865 .ioctl = st_ioctl,
3866 #ifdef CONFIG_COMPAT
3867 .compat_ioctl = st_compat_ioctl,
3868 #endif
3869 .open = st_open,
3870 .flush = st_flush,
3871 .release = st_release,
3872 };
3873
3874 static int st_probe(struct device *dev)
3875 {
3876 struct scsi_device *SDp = to_scsi_device(dev);
3877 struct gendisk *disk = NULL;
3878 struct cdev *cdev = NULL;
3879 struct scsi_tape *tpnt = NULL;
3880 struct st_modedef *STm;
3881 struct st_partstat *STps;
3882 struct st_buffer *buffer;
3883 int i, j, mode, dev_num, error;
3884 char *stp;
3885
3886 if (SDp->type != TYPE_TAPE)
3887 return -ENODEV;
3888 if ((stp = st_incompatible(SDp))) {
3889 sdev_printk(KERN_INFO, SDp, "Found incompatible tape\n");
3890 printk(KERN_INFO "st: The suggested driver is %s.\n", stp);
3891 return -ENODEV;
3892 }
3893
3894 i = min(SDp->request_queue->max_hw_segments,
3895 SDp->request_queue->max_phys_segments);
3896 if (st_max_sg_segs < i)
3897 i = st_max_sg_segs;
3898 buffer = new_tape_buffer(1, (SDp->host)->unchecked_isa_dma, i);
3899 if (buffer == NULL) {
3900 printk(KERN_ERR
3901 "st: Can't allocate new tape buffer. Device not attached.\n");
3902 goto out;
3903 }
3904
3905 disk = alloc_disk(1);
3906 if (!disk) {
3907 printk(KERN_ERR "st: out of memory. Device not attached.\n");
3908 goto out_buffer_free;
3909 }
3910
3911 write_lock(&st_dev_arr_lock);
3912 if (st_nr_dev >= st_dev_max) {
3913 struct scsi_tape **tmp_da;
3914 int tmp_dev_max;
3915
3916 tmp_dev_max = max(st_nr_dev * 2, 8);
3917 if (tmp_dev_max > ST_MAX_TAPES)
3918 tmp_dev_max = ST_MAX_TAPES;
3919 if (tmp_dev_max <= st_nr_dev) {
3920 write_unlock(&st_dev_arr_lock);
3921 printk(KERN_ERR "st: Too many tape devices (max. %d).\n",
3922 ST_MAX_TAPES);
3923 goto out_put_disk;
3924 }
3925
3926 tmp_da = kzalloc(tmp_dev_max * sizeof(struct scsi_tape *), GFP_ATOMIC);
3927 if (tmp_da == NULL) {
3928 write_unlock(&st_dev_arr_lock);
3929 printk(KERN_ERR "st: Can't extend device array.\n");
3930 goto out_put_disk;
3931 }
3932
3933 if (scsi_tapes != NULL) {
3934 memcpy(tmp_da, scsi_tapes,
3935 st_dev_max * sizeof(struct scsi_tape *));
3936 kfree(scsi_tapes);
3937 }
3938 scsi_tapes = tmp_da;
3939
3940 st_dev_max = tmp_dev_max;
3941 }
3942
3943 for (i = 0; i < st_dev_max; i++)
3944 if (scsi_tapes[i] == NULL)
3945 break;
3946 if (i >= st_dev_max)
3947 panic("scsi_devices corrupt (st)");
3948
3949 tpnt = kzalloc(sizeof(struct scsi_tape), GFP_ATOMIC);
3950 if (tpnt == NULL) {
3951 write_unlock(&st_dev_arr_lock);
3952 printk(KERN_ERR "st: Can't allocate device descriptor.\n");
3953 goto out_put_disk;
3954 }
3955 kref_init(&tpnt->kref);
3956 tpnt->disk = disk;
3957 sprintf(disk->disk_name, "st%d", i);
3958 disk->private_data = &tpnt->driver;
3959 disk->queue = SDp->request_queue;
3960 tpnt->driver = &st_template;
3961 scsi_tapes[i] = tpnt;
3962 dev_num = i;
3963
3964 tpnt->device = SDp;
3965 if (SDp->scsi_level <= 2)
3966 tpnt->tape_type = MT_ISSCSI1;
3967 else
3968 tpnt->tape_type = MT_ISSCSI2;
3969
3970 tpnt->buffer = buffer;
3971 tpnt->buffer->last_SRpnt = NULL;
3972
3973 tpnt->inited = 0;
3974 tpnt->dirty = 0;
3975 tpnt->in_use = 0;
3976 tpnt->drv_buffer = 1; /* Try buffering if no mode sense */
3977 tpnt->restr_dma = (SDp->host)->unchecked_isa_dma;
3978 tpnt->use_pf = (SDp->scsi_level >= SCSI_2);
3979 tpnt->density = 0;
3980 tpnt->do_auto_lock = ST_AUTO_LOCK;
3981 tpnt->can_bsr = (SDp->scsi_level > 2 ? 1 : ST_IN_FILE_POS); /* BSR mandatory in SCSI3 */
3982 tpnt->can_partitions = 0;
3983 tpnt->two_fm = ST_TWO_FM;
3984 tpnt->fast_mteom = ST_FAST_MTEOM;
3985 tpnt->scsi2_logical = ST_SCSI2LOGICAL;
3986 tpnt->immediate = ST_NOWAIT;
3987 tpnt->default_drvbuffer = 0xff; /* No forced buffering */
3988 tpnt->partition = 0;
3989 tpnt->new_partition = 0;
3990 tpnt->nbr_partitions = 0;
3991 tpnt->device->timeout = ST_TIMEOUT;
3992 tpnt->long_timeout = ST_LONG_TIMEOUT;
3993 tpnt->try_dio = try_direct_io && !SDp->host->unchecked_isa_dma;
3994
3995 for (i = 0; i < ST_NBR_MODES; i++) {
3996 STm = &(tpnt->modes[i]);
3997 STm->defined = 0;
3998 STm->sysv = ST_SYSV;
3999 STm->defaults_for_writes = 0;
4000 STm->do_async_writes = ST_ASYNC_WRITES;
4001 STm->do_buffer_writes = ST_BUFFER_WRITES;
4002 STm->do_read_ahead = ST_READ_AHEAD;
4003 STm->default_compression = ST_DONT_TOUCH;
4004 STm->default_blksize = (-1); /* No forced size */
4005 STm->default_density = (-1); /* No forced density */
4006 }
4007
4008 for (i = 0; i < ST_NBR_PARTITIONS; i++) {
4009 STps = &(tpnt->ps[i]);
4010 STps->rw = ST_IDLE;
4011 STps->eof = ST_NOEOF;
4012 STps->at_sm = 0;
4013 STps->last_block_valid = 0;
4014 STps->drv_block = (-1);
4015 STps->drv_file = (-1);
4016 }
4017
4018 tpnt->current_mode = 0;
4019 tpnt->modes[0].defined = 1;
4020
4021 tpnt->density_changed = tpnt->compression_changed =
4022 tpnt->blksize_changed = 0;
4023 init_MUTEX(&tpnt->lock);
4024
4025 st_nr_dev++;
4026 write_unlock(&st_dev_arr_lock);
4027
4028 for (mode = 0; mode < ST_NBR_MODES; ++mode) {
4029 STm = &(tpnt->modes[mode]);
4030 for (j=0; j < 2; j++) {
4031 cdev = cdev_alloc();
4032 if (!cdev) {
4033 printk(KERN_ERR
4034 "st%d: out of memory. Device not attached.\n",
4035 dev_num);
4036 goto out_free_tape;
4037 }
4038 cdev->owner = THIS_MODULE;
4039 cdev->ops = &st_fops;
4040
4041 error = cdev_add(cdev,
4042 MKDEV(SCSI_TAPE_MAJOR, TAPE_MINOR(dev_num, mode, j)),
4043 1);
4044 if (error) {
4045 printk(KERN_ERR "st%d: Can't add %s-rewind mode %d\n",
4046 dev_num, j ? "non" : "auto", mode);
4047 printk(KERN_ERR "st%d: Device not attached.\n", dev_num);
4048 goto out_free_tape;
4049 }
4050 STm->cdevs[j] = cdev;
4051
4052 }
4053 do_create_class_files(tpnt, dev_num, mode);
4054 }
4055
4056 sdev_printk(KERN_WARNING, SDp,
4057 "Attached scsi tape %s", tape_name(tpnt));
4058 printk(KERN_WARNING "%s: try direct i/o: %s (alignment %d B)\n",
4059 tape_name(tpnt), tpnt->try_dio ? "yes" : "no",
4060 queue_dma_alignment(SDp->request_queue) + 1);
4061
4062 return 0;
4063
4064 out_free_tape:
4065 for (mode=0; mode < ST_NBR_MODES; mode++) {
4066 STm = &(tpnt->modes[mode]);
4067 sysfs_remove_link(&tpnt->device->sdev_gendev.kobj,
4068 "tape");
4069 for (j=0; j < 2; j++) {
4070 if (STm->cdevs[j]) {
4071 if (cdev == STm->cdevs[j])
4072 cdev = NULL;
4073 class_device_destroy(st_sysfs_class,
4074 MKDEV(SCSI_TAPE_MAJOR,
4075 TAPE_MINOR(i, mode, j)));
4076 cdev_del(STm->cdevs[j]);
4077 }
4078 }
4079 }
4080 if (cdev)
4081 cdev_del(cdev);
4082 write_lock(&st_dev_arr_lock);
4083 scsi_tapes[dev_num] = NULL;
4084 st_nr_dev--;
4085 write_unlock(&st_dev_arr_lock);
4086 out_put_disk:
4087 put_disk(disk);
4088 kfree(tpnt);
4089 out_buffer_free:
4090 kfree(buffer);
4091 out:
4092 return -ENODEV;
4093 };
4094
4095
4096 static int st_remove(struct device *dev)
4097 {
4098 struct scsi_device *SDp = to_scsi_device(dev);
4099 struct scsi_tape *tpnt;
4100 int i, j, mode;
4101
4102 write_lock(&st_dev_arr_lock);
4103 for (i = 0; i < st_dev_max; i++) {
4104 tpnt = scsi_tapes[i];
4105 if (tpnt != NULL && tpnt->device == SDp) {
4106 scsi_tapes[i] = NULL;
4107 st_nr_dev--;
4108 write_unlock(&st_dev_arr_lock);
4109 sysfs_remove_link(&tpnt->device->sdev_gendev.kobj,
4110 "tape");
4111 for (mode = 0; mode < ST_NBR_MODES; ++mode) {
4112 for (j=0; j < 2; j++) {
4113 class_device_destroy(st_sysfs_class,
4114 MKDEV(SCSI_TAPE_MAJOR,
4115 TAPE_MINOR(i, mode, j)));
4116 cdev_del(tpnt->modes[mode].cdevs[j]);
4117 tpnt->modes[mode].cdevs[j] = NULL;
4118 }
4119 }
4120
4121 mutex_lock(&st_ref_mutex);
4122 kref_put(&tpnt->kref, scsi_tape_release);
4123 mutex_unlock(&st_ref_mutex);
4124 return 0;
4125 }
4126 }
4127
4128 write_unlock(&st_dev_arr_lock);
4129 return 0;
4130 }
4131
4132 /**
4133 * scsi_tape_release - Called to free the Scsi_Tape structure
4134 * @kref: pointer to embedded kref
4135 *
4136 * st_ref_mutex must be held entering this routine. Because it is
4137 * called on last put, you should always use the scsi_tape_get()
4138 * scsi_tape_put() helpers which manipulate the semaphore directly
4139 * and never do a direct kref_put().
4140 **/
4141 static void scsi_tape_release(struct kref *kref)
4142 {
4143 struct scsi_tape *tpnt = to_scsi_tape(kref);
4144 struct gendisk *disk = tpnt->disk;
4145
4146 tpnt->device = NULL;
4147
4148 if (tpnt->buffer) {
4149 tpnt->buffer->orig_frp_segs = 0;
4150 normalize_buffer(tpnt->buffer);
4151 kfree(tpnt->buffer);
4152 }
4153
4154 disk->private_data = NULL;
4155 put_disk(disk);
4156 kfree(tpnt);
4157 return;
4158 }
4159
4160 static int __init init_st(void)
4161 {
4162 validate_options();
4163
4164 printk(KERN_INFO
4165 "st: Version %s, fixed bufsize %d, s/g segs %d\n",
4166 verstr, st_fixed_buffer_size, st_max_sg_segs);
4167
4168 st_sysfs_class = class_create(THIS_MODULE, "scsi_tape");
4169 if (IS_ERR(st_sysfs_class)) {
4170 st_sysfs_class = NULL;
4171 printk(KERN_ERR "Unable create sysfs class for SCSI tapes\n");
4172 return 1;
4173 }
4174
4175 if (!register_chrdev_region(MKDEV(SCSI_TAPE_MAJOR, 0),
4176 ST_MAX_TAPE_ENTRIES, "st")) {
4177 if (scsi_register_driver(&st_template.gendrv) == 0) {
4178 do_create_driverfs_files();
4179 return 0;
4180 }
4181 unregister_chrdev_region(MKDEV(SCSI_TAPE_MAJOR, 0),
4182 ST_MAX_TAPE_ENTRIES);
4183 }
4184 class_destroy(st_sysfs_class);
4185
4186 printk(KERN_ERR "Unable to get major %d for SCSI tapes\n", SCSI_TAPE_MAJOR);
4187 return 1;
4188 }
4189
4190 static void __exit exit_st(void)
4191 {
4192 do_remove_driverfs_files();
4193 scsi_unregister_driver(&st_template.gendrv);
4194 unregister_chrdev_region(MKDEV(SCSI_TAPE_MAJOR, 0),
4195 ST_MAX_TAPE_ENTRIES);
4196 class_destroy(st_sysfs_class);
4197 kfree(scsi_tapes);
4198 printk(KERN_INFO "st: Unloaded.\n");
4199 }
4200
4201 module_init(init_st);
4202 module_exit(exit_st);
4203
4204
4205 /* The sysfs driver interface. Read-only at the moment */
4206 static ssize_t st_try_direct_io_show(struct device_driver *ddp, char *buf)
4207 {
4208 return snprintf(buf, PAGE_SIZE, "%d\n", try_direct_io);
4209 }
4210 static DRIVER_ATTR(try_direct_io, S_IRUGO, st_try_direct_io_show, NULL);
4211
4212 static ssize_t st_fixed_buffer_size_show(struct device_driver *ddp, char *buf)
4213 {
4214 return snprintf(buf, PAGE_SIZE, "%d\n", st_fixed_buffer_size);
4215 }
4216 static DRIVER_ATTR(fixed_buffer_size, S_IRUGO, st_fixed_buffer_size_show, NULL);
4217
4218 static ssize_t st_max_sg_segs_show(struct device_driver *ddp, char *buf)
4219 {
4220 return snprintf(buf, PAGE_SIZE, "%d\n", st_max_sg_segs);
4221 }
4222 static DRIVER_ATTR(max_sg_segs, S_IRUGO, st_max_sg_segs_show, NULL);
4223
4224 static ssize_t st_version_show(struct device_driver *ddd, char *buf)
4225 {
4226 return snprintf(buf, PAGE_SIZE, "[%s]\n", verstr);
4227 }
4228 static DRIVER_ATTR(version, S_IRUGO, st_version_show, NULL);
4229
4230 static void do_create_driverfs_files(void)
4231 {
4232 struct device_driver *driverfs = &st_template.gendrv;
4233
4234 driver_create_file(driverfs, &driver_attr_try_direct_io);
4235 driver_create_file(driverfs, &driver_attr_fixed_buffer_size);
4236 driver_create_file(driverfs, &driver_attr_max_sg_segs);
4237 driver_create_file(driverfs, &driver_attr_version);
4238 }
4239
4240 static void do_remove_driverfs_files(void)
4241 {
4242 struct device_driver *driverfs = &st_template.gendrv;
4243
4244 driver_remove_file(driverfs, &driver_attr_version);
4245 driver_remove_file(driverfs, &driver_attr_max_sg_segs);
4246 driver_remove_file(driverfs, &driver_attr_fixed_buffer_size);
4247 driver_remove_file(driverfs, &driver_attr_try_direct_io);
4248 }
4249
4250
4251 /* The sysfs simple class interface */
4252 static ssize_t st_defined_show(struct class_device *class_dev, char *buf)
4253 {
4254 struct st_modedef *STm = (struct st_modedef *)class_get_devdata(class_dev);
4255 ssize_t l = 0;
4256
4257 l = snprintf(buf, PAGE_SIZE, "%d\n", STm->defined);
4258 return l;
4259 }
4260
4261 CLASS_DEVICE_ATTR(defined, S_IRUGO, st_defined_show, NULL);
4262
4263 static ssize_t st_defblk_show(struct class_device *class_dev, char *buf)
4264 {
4265 struct st_modedef *STm = (struct st_modedef *)class_get_devdata(class_dev);
4266 ssize_t l = 0;
4267
4268 l = snprintf(buf, PAGE_SIZE, "%d\n", STm->default_blksize);
4269 return l;
4270 }
4271
4272 CLASS_DEVICE_ATTR(default_blksize, S_IRUGO, st_defblk_show, NULL);
4273
4274 static ssize_t st_defdensity_show(struct class_device *class_dev, char *buf)
4275 {
4276 struct st_modedef *STm = (struct st_modedef *)class_get_devdata(class_dev);
4277 ssize_t l = 0;
4278 char *fmt;
4279
4280 fmt = STm->default_density >= 0 ? "0x%02x\n" : "%d\n";
4281 l = snprintf(buf, PAGE_SIZE, fmt, STm->default_density);
4282 return l;
4283 }
4284
4285 CLASS_DEVICE_ATTR(default_density, S_IRUGO, st_defdensity_show, NULL);
4286
4287 static ssize_t st_defcompression_show(struct class_device *class_dev, char *buf)
4288 {
4289 struct st_modedef *STm = (struct st_modedef *)class_get_devdata(class_dev);
4290 ssize_t l = 0;
4291
4292 l = snprintf(buf, PAGE_SIZE, "%d\n", STm->default_compression - 1);
4293 return l;
4294 }
4295
4296 CLASS_DEVICE_ATTR(default_compression, S_IRUGO, st_defcompression_show, NULL);
4297
4298 static void do_create_class_files(struct scsi_tape *STp, int dev_num, int mode)
4299 {
4300 int i, rew, error;
4301 char name[10];
4302 struct class_device *st_class_member;
4303
4304 if (!st_sysfs_class)
4305 return;
4306
4307 for (rew=0; rew < 2; rew++) {
4308 /* Make sure that the minor numbers corresponding to the four
4309 first modes always get the same names */
4310 i = mode << (4 - ST_NBR_MODE_BITS);
4311 snprintf(name, 10, "%s%s%s", rew ? "n" : "",
4312 STp->disk->disk_name, st_formats[i]);
4313 st_class_member =
4314 class_device_create(st_sysfs_class, NULL,
4315 MKDEV(SCSI_TAPE_MAJOR,
4316 TAPE_MINOR(dev_num, mode, rew)),
4317 &STp->device->sdev_gendev, "%s", name);
4318 if (IS_ERR(st_class_member)) {
4319 printk(KERN_WARNING "st%d: class_device_create failed\n",
4320 dev_num);
4321 goto out;
4322 }
4323 class_set_devdata(st_class_member, &STp->modes[mode]);
4324
4325 class_device_create_file(st_class_member,
4326 &class_device_attr_defined);
4327 class_device_create_file(st_class_member,
4328 &class_device_attr_default_blksize);
4329 class_device_create_file(st_class_member,
4330 &class_device_attr_default_density);
4331 class_device_create_file(st_class_member,
4332 &class_device_attr_default_compression);
4333 if (mode == 0 && rew == 0) {
4334 error = sysfs_create_link(&STp->device->sdev_gendev.kobj,
4335 &st_class_member->kobj,
4336 "tape");
4337 if (error) {
4338 printk(KERN_ERR
4339 "st%d: Can't create sysfs link from SCSI device.\n",
4340 dev_num);
4341 }
4342 }
4343 }
4344 out:
4345 return;
4346 }
4347
4348 /* The following functions may be useful for a larger audience. */
4349 static int sgl_map_user_pages(struct scatterlist *sgl, const unsigned int max_pages,
4350 unsigned long uaddr, size_t count, int rw)
4351 {
4352 unsigned long end = (uaddr + count + PAGE_SIZE - 1) >> PAGE_SHIFT;
4353 unsigned long start = uaddr >> PAGE_SHIFT;
4354 const int nr_pages = end - start;
4355 int res, i, j;
4356 struct page **pages;
4357
4358 /* User attempted Overflow! */
4359 if ((uaddr + count) < uaddr)
4360 return -EINVAL;
4361
4362 /* Too big */
4363 if (nr_pages > max_pages)
4364 return -ENOMEM;
4365
4366 /* Hmm? */
4367 if (count == 0)
4368 return 0;
4369
4370 if ((pages = kmalloc(max_pages * sizeof(*pages), GFP_KERNEL)) == NULL)
4371 return -ENOMEM;
4372
4373 /* Try to fault in all of the necessary pages */
4374 down_read(&current->mm->mmap_sem);
4375 /* rw==READ means read from drive, write into memory area */
4376 res = get_user_pages(
4377 current,
4378 current->mm,
4379 uaddr,
4380 nr_pages,
4381 rw == READ,
4382 0, /* don't force */
4383 pages,
4384 NULL);
4385 up_read(&current->mm->mmap_sem);
4386
4387 /* Errors and no page mapped should return here */
4388 if (res < nr_pages)
4389 goto out_unmap;
4390
4391 for (i=0; i < nr_pages; i++) {
4392 /* FIXME: flush superflous for rw==READ,
4393 * probably wrong function for rw==WRITE
4394 */
4395 flush_dcache_page(pages[i]);
4396 }
4397
4398 /* Populate the scatter/gather list */
4399 sgl[0].page = pages[0];
4400 sgl[0].offset = uaddr & ~PAGE_MASK;
4401 if (nr_pages > 1) {
4402 sgl[0].length = PAGE_SIZE - sgl[0].offset;
4403 count -= sgl[0].length;
4404 for (i=1; i < nr_pages ; i++) {
4405 sgl[i].offset = 0;
4406 sgl[i].page = pages[i];
4407 sgl[i].length = count < PAGE_SIZE ? count : PAGE_SIZE;
4408 count -= PAGE_SIZE;
4409 }
4410 }
4411 else {
4412 sgl[0].length = count;
4413 }
4414
4415 kfree(pages);
4416 return nr_pages;
4417
4418 out_unmap:
4419 if (res > 0) {
4420 for (j=0; j < res; j++)
4421 page_cache_release(pages[j]);
4422 res = 0;
4423 }
4424 kfree(pages);
4425 return res;
4426 }
4427
4428
4429 /* And unmap them... */
4430 static int sgl_unmap_user_pages(struct scatterlist *sgl, const unsigned int nr_pages,
4431 int dirtied)
4432 {
4433 int i;
4434
4435 for (i=0; i < nr_pages; i++) {
4436 struct page *page = sgl[i].page;
4437
4438 if (dirtied)
4439 SetPageDirty(page);
4440 /* FIXME: cache flush missing for rw==READ
4441 * FIXME: call the correct reference counting function
4442 */
4443 page_cache_release(page);
4444 }
4445
4446 return 0;
4447 }
Support for the Chinese Samsung S3C2440 based development boards