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 - 2008 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 = "20081215";
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 #include <linux/smp_lock.h>
42
43 #include <asm/uaccess.h>
44 #include <asm/dma.h>
45 #include <asm/system.h>
46
47 #include <scsi/scsi.h>
48 #include <scsi/scsi_dbg.h>
49 #include <scsi/scsi_device.h>
50 #include <scsi/scsi_driver.h>
51 #include <scsi/scsi_eh.h>
52 #include <scsi/scsi_host.h>
53 #include <scsi/scsi_ioctl.h>
54 #include <scsi/sg.h>
55
56
57 /* The driver prints some debugging information on the console if DEBUG
58 is defined and non-zero. */
59 #define DEBUG 0
60
61 #if DEBUG
62 /* The message level for the debug messages is currently set to KERN_NOTICE
63 so that people can easily see the messages. Later when the debugging messages
64 in the drivers are more widely classified, this may be changed to KERN_DEBUG. */
65 #define ST_DEB_MSG KERN_NOTICE
66 #define DEB(a) a
67 #define DEBC(a) if (debugging) { a ; }
68 #else
69 #define DEB(a)
70 #define DEBC(a)
71 #endif
72
73 #define ST_KILOBYTE 1024
74
75 #include "st_options.h"
76 #include "st.h"
77
78 static int buffer_kbs;
79 static int max_sg_segs;
80 static int try_direct_io = TRY_DIRECT_IO;
81 static int try_rdio = 1;
82 static int try_wdio = 1;
83
84 static int st_dev_max;
85 static int st_nr_dev;
86
87 static struct class *st_sysfs_class;
88
89 MODULE_AUTHOR("Kai Makisara");
90 MODULE_DESCRIPTION("SCSI tape (st) driver");
91 MODULE_LICENSE("GPL");
92 MODULE_ALIAS_CHARDEV_MAJOR(SCSI_TAPE_MAJOR);
93 MODULE_ALIAS_SCSI_DEVICE(TYPE_TAPE);
94
95 /* Set 'perm' (4th argument) to 0 to disable module_param's definition
96 * of sysfs parameters (which module_param doesn't yet support).
97 * Sysfs parameters defined explicitly later.
98 */
99 module_param_named(buffer_kbs, buffer_kbs, int, 0);
100 MODULE_PARM_DESC(buffer_kbs, "Default driver buffer size for fixed block mode (KB; 32)");
101 module_param_named(max_sg_segs, max_sg_segs, int, 0);
102 MODULE_PARM_DESC(max_sg_segs, "Maximum number of scatter/gather segments to use (256)");
103 module_param_named(try_direct_io, try_direct_io, int, 0);
104 MODULE_PARM_DESC(try_direct_io, "Try direct I/O between user buffer and tape drive (1)");
105
106 /* Extra parameters for testing */
107 module_param_named(try_rdio, try_rdio, int, 0);
108 MODULE_PARM_DESC(try_rdio, "Try direct read i/o when possible");
109 module_param_named(try_wdio, try_wdio, int, 0);
110 MODULE_PARM_DESC(try_wdio, "Try direct write i/o when possible");
111
112 #ifndef MODULE
113 static int write_threshold_kbs; /* retained for compatibility */
114 static struct st_dev_parm {
115 char *name;
116 int *val;
117 } parms[] __initdata = {
118 {
119 "buffer_kbs", &buffer_kbs
120 },
121 { /* Retained for compatibility with 2.4 */
122 "write_threshold_kbs", &write_threshold_kbs
123 },
124 {
125 "max_sg_segs", NULL
126 },
127 {
128 "try_direct_io", &try_direct_io
129 }
130 };
131 #endif
132
133 /* Restrict the number of modes so that names for all are assigned */
134 #if ST_NBR_MODES > 16
135 #error "Maximum number of modes is 16"
136 #endif
137 /* Bit reversed order to get same names for same minors with all
138 mode counts */
139 static const char *st_formats[] = {
140 "", "r", "k", "s", "l", "t", "o", "u",
141 "m", "v", "p", "x", "a", "y", "q", "z"};
142
143 /* The default definitions have been moved to st_options.h */
144
145 #define ST_FIXED_BUFFER_SIZE (ST_FIXED_BUFFER_BLOCKS * ST_KILOBYTE)
146
147 /* The buffer size should fit into the 24 bits for length in the
148 6-byte SCSI read and write commands. */
149 #if ST_FIXED_BUFFER_SIZE >= (2 << 24 - 1)
150 #error "Buffer size should not exceed (2 << 24 - 1) bytes!"
151 #endif
152
153 static int debugging = DEBUG;
154
155 #define MAX_RETRIES 0
156 #define MAX_WRITE_RETRIES 0
157 #define MAX_READY_RETRIES 0
158 #define NO_TAPE NOT_READY
159
160 #define ST_TIMEOUT (900 * HZ)
161 #define ST_LONG_TIMEOUT (14000 * HZ)
162
163 /* Remove mode bits and auto-rewind bit (7) */
164 #define TAPE_NR(x) ( ((iminor(x) & ~255) >> (ST_NBR_MODE_BITS + 1)) | \
165 (iminor(x) & ~(-1 << ST_MODE_SHIFT)) )
166 #define TAPE_MODE(x) ((iminor(x) & ST_MODE_MASK) >> ST_MODE_SHIFT)
167
168 /* Construct the minor number from the device (d), mode (m), and non-rewind (n) data */
169 #define TAPE_MINOR(d, m, n) (((d & ~(255 >> (ST_NBR_MODE_BITS + 1))) << (ST_NBR_MODE_BITS + 1)) | \
170 (d & (255 >> (ST_NBR_MODE_BITS + 1))) | (m << ST_MODE_SHIFT) | ((n != 0) << 7) )
171
172 /* Internal ioctl to set both density (uppermost 8 bits) and blocksize (lower
173 24 bits) */
174 #define SET_DENS_AND_BLK 0x10001
175
176 static DEFINE_RWLOCK(st_dev_arr_lock);
177
178 static int st_fixed_buffer_size = ST_FIXED_BUFFER_SIZE;
179 static int st_max_sg_segs = ST_MAX_SG;
180
181 static struct scsi_tape **scsi_tapes = NULL;
182
183 static int modes_defined;
184
185 static int enlarge_buffer(struct st_buffer *, int, int);
186 static void clear_buffer(struct st_buffer *);
187 static void normalize_buffer(struct st_buffer *);
188 static int append_to_buffer(const char __user *, struct st_buffer *, int);
189 static int from_buffer(struct st_buffer *, char __user *, int);
190 static void move_buffer_data(struct st_buffer *, int);
191
192 static int sgl_map_user_pages(struct st_buffer *, const unsigned int,
193 unsigned long, size_t, int);
194 static int sgl_unmap_user_pages(struct st_buffer *, const unsigned int, int);
195
196 static int st_probe(struct device *);
197 static int st_remove(struct device *);
198
199 static int do_create_sysfs_files(void);
200 static void do_remove_sysfs_files(void);
201 static int do_create_class_files(struct scsi_tape *, int, int);
202
203 static struct scsi_driver st_template = {
204 .owner = THIS_MODULE,
205 .gendrv = {
206 .name = "st",
207 .probe = st_probe,
208 .remove = st_remove,
209 },
210 };
211
212 static int st_compression(struct scsi_tape *, int);
213
214 static int find_partition(struct scsi_tape *);
215 static int switch_partition(struct scsi_tape *);
216
217 static int st_int_ioctl(struct scsi_tape *, unsigned int, unsigned long);
218
219 static void scsi_tape_release(struct kref *);
220
221 #define to_scsi_tape(obj) container_of(obj, struct scsi_tape, kref)
222
223 static DEFINE_MUTEX(st_ref_mutex);
224
225
226 #include "osst_detect.h"
227 #ifndef SIGS_FROM_OSST
228 #define SIGS_FROM_OSST \
229 {"OnStream", "SC-", "", "osst"}, \
230 {"OnStream", "DI-", "", "osst"}, \
231 {"OnStream", "DP-", "", "osst"}, \
232 {"OnStream", "USB", "", "osst"}, \
233 {"OnStream", "FW-", "", "osst"}
234 #endif
235
236 static struct scsi_tape *scsi_tape_get(int dev)
237 {
238 struct scsi_tape *STp = NULL;
239
240 mutex_lock(&st_ref_mutex);
241 write_lock(&st_dev_arr_lock);
242
243 if (dev < st_dev_max && scsi_tapes != NULL)
244 STp = scsi_tapes[dev];
245 if (!STp) goto out;
246
247 kref_get(&STp->kref);
248
249 if (!STp->device)
250 goto out_put;
251
252 if (scsi_device_get(STp->device))
253 goto out_put;
254
255 goto out;
256
257 out_put:
258 kref_put(&STp->kref, scsi_tape_release);
259 STp = NULL;
260 out:
261 write_unlock(&st_dev_arr_lock);
262 mutex_unlock(&st_ref_mutex);
263 return STp;
264 }
265
266 static void scsi_tape_put(struct scsi_tape *STp)
267 {
268 struct scsi_device *sdev = STp->device;
269
270 mutex_lock(&st_ref_mutex);
271 kref_put(&STp->kref, scsi_tape_release);
272 scsi_device_put(sdev);
273 mutex_unlock(&st_ref_mutex);
274 }
275
276 struct st_reject_data {
277 char *vendor;
278 char *model;
279 char *rev;
280 char *driver_hint; /* Name of the correct driver, NULL if unknown */
281 };
282
283 static struct st_reject_data reject_list[] = {
284 /* {"XXX", "Yy-", "", NULL}, example */
285 SIGS_FROM_OSST,
286 {NULL, }};
287
288 /* If the device signature is on the list of incompatible drives, the
289 function returns a pointer to the name of the correct driver (if known) */
290 static char * st_incompatible(struct scsi_device* SDp)
291 {
292 struct st_reject_data *rp;
293
294 for (rp=&(reject_list[0]); rp->vendor != NULL; rp++)
295 if (!strncmp(rp->vendor, SDp->vendor, strlen(rp->vendor)) &&
296 !strncmp(rp->model, SDp->model, strlen(rp->model)) &&
297 !strncmp(rp->rev, SDp->rev, strlen(rp->rev))) {
298 if (rp->driver_hint)
299 return rp->driver_hint;
300 else
301 return "unknown";
302 }
303 return NULL;
304 }
305
306
307 static inline char *tape_name(struct scsi_tape *tape)
308 {
309 return tape->disk->disk_name;
310 }
311
312
313 static void st_analyze_sense(struct st_request *SRpnt, struct st_cmdstatus *s)
314 {
315 const u8 *ucp;
316 const u8 *sense = SRpnt->sense;
317
318 s->have_sense = scsi_normalize_sense(SRpnt->sense,
319 SCSI_SENSE_BUFFERSIZE, &s->sense_hdr);
320 s->flags = 0;
321
322 if (s->have_sense) {
323 s->deferred = 0;
324 s->remainder_valid =
325 scsi_get_sense_info_fld(sense, SCSI_SENSE_BUFFERSIZE, &s->uremainder64);
326 switch (sense[0] & 0x7f) {
327 case 0x71:
328 s->deferred = 1;
329 case 0x70:
330 s->fixed_format = 1;
331 s->flags = sense[2] & 0xe0;
332 break;
333 case 0x73:
334 s->deferred = 1;
335 case 0x72:
336 s->fixed_format = 0;
337 ucp = scsi_sense_desc_find(sense, SCSI_SENSE_BUFFERSIZE, 4);
338 s->flags = ucp ? (ucp[3] & 0xe0) : 0;
339 break;
340 }
341 }
342 }
343
344
345 /* Convert the result to success code */
346 static int st_chk_result(struct scsi_tape *STp, struct st_request * SRpnt)
347 {
348 int result = SRpnt->result;
349 u8 scode;
350 DEB(const char *stp;)
351 char *name = tape_name(STp);
352 struct st_cmdstatus *cmdstatp;
353
354 if (!result)
355 return 0;
356
357 cmdstatp = &STp->buffer->cmdstat;
358 st_analyze_sense(SRpnt, cmdstatp);
359
360 if (cmdstatp->have_sense)
361 scode = STp->buffer->cmdstat.sense_hdr.sense_key;
362 else
363 scode = 0;
364
365 DEB(
366 if (debugging) {
367 printk(ST_DEB_MSG "%s: Error: %x, cmd: %x %x %x %x %x %x\n",
368 name, result,
369 SRpnt->cmd[0], SRpnt->cmd[1], SRpnt->cmd[2],
370 SRpnt->cmd[3], SRpnt->cmd[4], SRpnt->cmd[5]);
371 if (cmdstatp->have_sense)
372 __scsi_print_sense(name, SRpnt->sense, SCSI_SENSE_BUFFERSIZE);
373 } ) /* end DEB */
374 if (!debugging) { /* Abnormal conditions for tape */
375 if (!cmdstatp->have_sense)
376 printk(KERN_WARNING
377 "%s: Error %x (driver bt 0x%x, host bt 0x%x).\n",
378 name, result, driver_byte(result),
379 host_byte(result));
380 else if (cmdstatp->have_sense &&
381 scode != NO_SENSE &&
382 scode != RECOVERED_ERROR &&
383 /* scode != UNIT_ATTENTION && */
384 scode != BLANK_CHECK &&
385 scode != VOLUME_OVERFLOW &&
386 SRpnt->cmd[0] != MODE_SENSE &&
387 SRpnt->cmd[0] != TEST_UNIT_READY) {
388
389 __scsi_print_sense(name, SRpnt->sense, 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 static struct st_request *st_allocate_request(struct scsi_tape *stp)
437 {
438 struct st_request *streq;
439
440 streq = kzalloc(sizeof(*streq), GFP_KERNEL);
441 if (streq)
442 streq->stp = stp;
443 else {
444 DEBC(printk(KERN_ERR "%s: Can't get SCSI request.\n",
445 tape_name(stp)););
446 if (signal_pending(current))
447 stp->buffer->syscall_result = -EINTR;
448 else
449 stp->buffer->syscall_result = -EBUSY;
450 }
451
452 return streq;
453 }
454
455 static void st_release_request(struct st_request *streq)
456 {
457 kfree(streq);
458 }
459
460 static void st_scsi_execute_end(struct request *req, int uptodate)
461 {
462 struct st_request *SRpnt = req->end_io_data;
463 struct scsi_tape *STp = SRpnt->stp;
464
465 STp->buffer->cmdstat.midlevel_result = SRpnt->result = req->errors;
466 STp->buffer->cmdstat.residual = req->resid_len;
467
468 if (SRpnt->waiting)
469 complete(SRpnt->waiting);
470
471 blk_rq_unmap_user(SRpnt->bio);
472 __blk_put_request(req->q, req);
473 }
474
475 static int st_scsi_execute(struct st_request *SRpnt, const unsigned char *cmd,
476 int data_direction, void *buffer, unsigned bufflen,
477 int timeout, int retries)
478 {
479 struct request *req;
480 struct rq_map_data *mdata = &SRpnt->stp->buffer->map_data;
481 int err = 0;
482 int write = (data_direction == DMA_TO_DEVICE);
483
484 req = blk_get_request(SRpnt->stp->device->request_queue, write,
485 GFP_KERNEL);
486 if (!req)
487 return DRIVER_ERROR << 24;
488
489 req->cmd_type = REQ_TYPE_BLOCK_PC;
490 req->cmd_flags |= REQ_QUIET;
491
492 mdata->null_mapped = 1;
493
494 if (bufflen) {
495 err = blk_rq_map_user(req->q, req, mdata, NULL, bufflen,
496 GFP_KERNEL);
497 if (err) {
498 blk_put_request(req);
499 return DRIVER_ERROR << 24;
500 }
501 }
502
503 SRpnt->bio = req->bio;
504 req->cmd_len = COMMAND_SIZE(cmd[0]);
505 memset(req->cmd, 0, BLK_MAX_CDB);
506 memcpy(req->cmd, cmd, req->cmd_len);
507 req->sense = SRpnt->sense;
508 req->sense_len = 0;
509 req->timeout = timeout;
510 req->retries = retries;
511 req->end_io_data = SRpnt;
512
513 blk_execute_rq_nowait(req->q, NULL, req, 1, st_scsi_execute_end);
514 return 0;
515 }
516
517 /* Do the scsi command. Waits until command performed if do_wait is true.
518 Otherwise write_behind_check() is used to check that the command
519 has finished. */
520 static struct st_request *
521 st_do_scsi(struct st_request * SRpnt, struct scsi_tape * STp, unsigned char *cmd,
522 int bytes, int direction, int timeout, int retries, int do_wait)
523 {
524 struct completion *waiting;
525 struct rq_map_data *mdata = &STp->buffer->map_data;
526 int ret;
527
528 /* if async, make sure there's no command outstanding */
529 if (!do_wait && ((STp->buffer)->last_SRpnt)) {
530 printk(KERN_ERR "%s: Async command already active.\n",
531 tape_name(STp));
532 if (signal_pending(current))
533 (STp->buffer)->syscall_result = (-EINTR);
534 else
535 (STp->buffer)->syscall_result = (-EBUSY);
536 return NULL;
537 }
538
539 if (!SRpnt) {
540 SRpnt = st_allocate_request(STp);
541 if (!SRpnt)
542 return NULL;
543 }
544
545 /* If async IO, set last_SRpnt. This ptr tells write_behind_check
546 which IO is outstanding. It's nulled out when the IO completes. */
547 if (!do_wait)
548 (STp->buffer)->last_SRpnt = SRpnt;
549
550 waiting = &STp->wait;
551 init_completion(waiting);
552 SRpnt->waiting = waiting;
553
554 if (STp->buffer->do_dio) {
555 mdata->nr_entries = STp->buffer->sg_segs;
556 mdata->pages = STp->buffer->mapped_pages;
557 } else {
558 mdata->nr_entries =
559 DIV_ROUND_UP(bytes, PAGE_SIZE << mdata->page_order);
560 STp->buffer->map_data.pages = STp->buffer->reserved_pages;
561 STp->buffer->map_data.offset = 0;
562 }
563
564 memcpy(SRpnt->cmd, cmd, sizeof(SRpnt->cmd));
565 STp->buffer->cmdstat.have_sense = 0;
566 STp->buffer->syscall_result = 0;
567
568 ret = st_scsi_execute(SRpnt, cmd, direction, NULL, bytes, timeout,
569 retries);
570 if (ret) {
571 /* could not allocate the buffer or request was too large */
572 (STp->buffer)->syscall_result = (-EBUSY);
573 (STp->buffer)->last_SRpnt = NULL;
574 } else if (do_wait) {
575 wait_for_completion(waiting);
576 SRpnt->waiting = NULL;
577 (STp->buffer)->syscall_result = st_chk_result(STp, SRpnt);
578 }
579
580 return SRpnt;
581 }
582
583
584 /* Handle the write-behind checking (waits for completion). Returns -ENOSPC if
585 write has been correct but EOM early warning reached, -EIO if write ended in
586 error or zero if write successful. Asynchronous writes are used only in
587 variable block mode. */
588 static int write_behind_check(struct scsi_tape * STp)
589 {
590 int retval = 0;
591 struct st_buffer *STbuffer;
592 struct st_partstat *STps;
593 struct st_cmdstatus *cmdstatp;
594 struct st_request *SRpnt;
595
596 STbuffer = STp->buffer;
597 if (!STbuffer->writing)
598 return 0;
599
600 DEB(
601 if (STp->write_pending)
602 STp->nbr_waits++;
603 else
604 STp->nbr_finished++;
605 ) /* end DEB */
606
607 wait_for_completion(&(STp->wait));
608 SRpnt = STbuffer->last_SRpnt;
609 STbuffer->last_SRpnt = NULL;
610 SRpnt->waiting = NULL;
611
612 (STp->buffer)->syscall_result = st_chk_result(STp, SRpnt);
613 st_release_request(SRpnt);
614
615 STbuffer->buffer_bytes -= STbuffer->writing;
616 STps = &(STp->ps[STp->partition]);
617 if (STps->drv_block >= 0) {
618 if (STp->block_size == 0)
619 STps->drv_block++;
620 else
621 STps->drv_block += STbuffer->writing / STp->block_size;
622 }
623
624 cmdstatp = &STbuffer->cmdstat;
625 if (STbuffer->syscall_result) {
626 retval = -EIO;
627 if (cmdstatp->have_sense && !cmdstatp->deferred &&
628 (cmdstatp->flags & SENSE_EOM) &&
629 (cmdstatp->sense_hdr.sense_key == NO_SENSE ||
630 cmdstatp->sense_hdr.sense_key == RECOVERED_ERROR)) {
631 /* EOM at write-behind, has all data been written? */
632 if (!cmdstatp->remainder_valid ||
633 cmdstatp->uremainder64 == 0)
634 retval = -ENOSPC;
635 }
636 if (retval == -EIO)
637 STps->drv_block = -1;
638 }
639 STbuffer->writing = 0;
640
641 DEB(if (debugging && retval)
642 printk(ST_DEB_MSG "%s: Async write error %x, return value %d.\n",
643 tape_name(STp), STbuffer->cmdstat.midlevel_result, retval);) /* end DEB */
644
645 return retval;
646 }
647
648
649 /* Step over EOF if it has been inadvertently crossed (ioctl not used because
650 it messes up the block number). */
651 static int cross_eof(struct scsi_tape * STp, int forward)
652 {
653 struct st_request *SRpnt;
654 unsigned char cmd[MAX_COMMAND_SIZE];
655
656 cmd[0] = SPACE;
657 cmd[1] = 0x01; /* Space FileMarks */
658 if (forward) {
659 cmd[2] = cmd[3] = 0;
660 cmd[4] = 1;
661 } else
662 cmd[2] = cmd[3] = cmd[4] = 0xff; /* -1 filemarks */
663 cmd[5] = 0;
664
665 DEBC(printk(ST_DEB_MSG "%s: Stepping over filemark %s.\n",
666 tape_name(STp), forward ? "forward" : "backward"));
667
668 SRpnt = st_do_scsi(NULL, STp, cmd, 0, DMA_NONE,
669 STp->device->request_queue->rq_timeout,
670 MAX_RETRIES, 1);
671 if (!SRpnt)
672 return (STp->buffer)->syscall_result;
673
674 st_release_request(SRpnt);
675 SRpnt = NULL;
676
677 if ((STp->buffer)->cmdstat.midlevel_result != 0)
678 printk(KERN_ERR "%s: Stepping over filemark %s failed.\n",
679 tape_name(STp), forward ? "forward" : "backward");
680
681 return (STp->buffer)->syscall_result;
682 }
683
684
685 /* Flush the write buffer (never need to write if variable blocksize). */
686 static int st_flush_write_buffer(struct scsi_tape * STp)
687 {
688 int transfer, blks;
689 int result;
690 unsigned char cmd[MAX_COMMAND_SIZE];
691 struct st_request *SRpnt;
692 struct st_partstat *STps;
693
694 result = write_behind_check(STp);
695 if (result)
696 return result;
697
698 result = 0;
699 if (STp->dirty == 1) {
700
701 transfer = STp->buffer->buffer_bytes;
702 DEBC(printk(ST_DEB_MSG "%s: Flushing %d bytes.\n",
703 tape_name(STp), transfer));
704
705 memset(cmd, 0, MAX_COMMAND_SIZE);
706 cmd[0] = WRITE_6;
707 cmd[1] = 1;
708 blks = transfer / STp->block_size;
709 cmd[2] = blks >> 16;
710 cmd[3] = blks >> 8;
711 cmd[4] = blks;
712
713 SRpnt = st_do_scsi(NULL, STp, cmd, transfer, DMA_TO_DEVICE,
714 STp->device->request_queue->rq_timeout,
715 MAX_WRITE_RETRIES, 1);
716 if (!SRpnt)
717 return (STp->buffer)->syscall_result;
718
719 STps = &(STp->ps[STp->partition]);
720 if ((STp->buffer)->syscall_result != 0) {
721 struct st_cmdstatus *cmdstatp = &STp->buffer->cmdstat;
722
723 if (cmdstatp->have_sense && !cmdstatp->deferred &&
724 (cmdstatp->flags & SENSE_EOM) &&
725 (cmdstatp->sense_hdr.sense_key == NO_SENSE ||
726 cmdstatp->sense_hdr.sense_key == RECOVERED_ERROR) &&
727 (!cmdstatp->remainder_valid ||
728 cmdstatp->uremainder64 == 0)) { /* All written at EOM early warning */
729 STp->dirty = 0;
730 (STp->buffer)->buffer_bytes = 0;
731 if (STps->drv_block >= 0)
732 STps->drv_block += blks;
733 result = (-ENOSPC);
734 } else {
735 printk(KERN_ERR "%s: Error on flush.\n",
736 tape_name(STp));
737 STps->drv_block = (-1);
738 result = (-EIO);
739 }
740 } else {
741 if (STps->drv_block >= 0)
742 STps->drv_block += blks;
743 STp->dirty = 0;
744 (STp->buffer)->buffer_bytes = 0;
745 }
746 st_release_request(SRpnt);
747 SRpnt = NULL;
748 }
749 return result;
750 }
751
752
753 /* Flush the tape buffer. The tape will be positioned correctly unless
754 seek_next is true. */
755 static int flush_buffer(struct scsi_tape *STp, int seek_next)
756 {
757 int backspace, result;
758 struct st_buffer *STbuffer;
759 struct st_partstat *STps;
760
761 STbuffer = STp->buffer;
762
763 /*
764 * If there was a bus reset, block further access
765 * to this device.
766 */
767 if (STp->pos_unknown)
768 return (-EIO);
769
770 if (STp->ready != ST_READY)
771 return 0;
772 STps = &(STp->ps[STp->partition]);
773 if (STps->rw == ST_WRITING) /* Writing */
774 return st_flush_write_buffer(STp);
775
776 if (STp->block_size == 0)
777 return 0;
778
779 backspace = ((STp->buffer)->buffer_bytes +
780 (STp->buffer)->read_pointer) / STp->block_size -
781 ((STp->buffer)->read_pointer + STp->block_size - 1) /
782 STp->block_size;
783 (STp->buffer)->buffer_bytes = 0;
784 (STp->buffer)->read_pointer = 0;
785 result = 0;
786 if (!seek_next) {
787 if (STps->eof == ST_FM_HIT) {
788 result = cross_eof(STp, 0); /* Back over the EOF hit */
789 if (!result)
790 STps->eof = ST_NOEOF;
791 else {
792 if (STps->drv_file >= 0)
793 STps->drv_file++;
794 STps->drv_block = 0;
795 }
796 }
797 if (!result && backspace > 0)
798 result = st_int_ioctl(STp, MTBSR, backspace);
799 } else if (STps->eof == ST_FM_HIT) {
800 if (STps->drv_file >= 0)
801 STps->drv_file++;
802 STps->drv_block = 0;
803 STps->eof = ST_NOEOF;
804 }
805 return result;
806
807 }
808
809 /* Set the mode parameters */
810 static int set_mode_densblk(struct scsi_tape * STp, struct st_modedef * STm)
811 {
812 int set_it = 0;
813 unsigned long arg;
814 char *name = tape_name(STp);
815
816 if (!STp->density_changed &&
817 STm->default_density >= 0 &&
818 STm->default_density != STp->density) {
819 arg = STm->default_density;
820 set_it = 1;
821 } else
822 arg = STp->density;
823 arg <<= MT_ST_DENSITY_SHIFT;
824 if (!STp->blksize_changed &&
825 STm->default_blksize >= 0 &&
826 STm->default_blksize != STp->block_size) {
827 arg |= STm->default_blksize;
828 set_it = 1;
829 } else
830 arg |= STp->block_size;
831 if (set_it &&
832 st_int_ioctl(STp, SET_DENS_AND_BLK, arg)) {
833 printk(KERN_WARNING
834 "%s: Can't set default block size to %d bytes and density %x.\n",
835 name, STm->default_blksize, STm->default_density);
836 if (modes_defined)
837 return (-EINVAL);
838 }
839 return 0;
840 }
841
842
843 /* Lock or unlock the drive door. Don't use when st_request allocated. */
844 static int do_door_lock(struct scsi_tape * STp, int do_lock)
845 {
846 int retval, cmd;
847 DEB(char *name = tape_name(STp);)
848
849
850 cmd = do_lock ? SCSI_IOCTL_DOORLOCK : SCSI_IOCTL_DOORUNLOCK;
851 DEBC(printk(ST_DEB_MSG "%s: %socking drive door.\n", name,
852 do_lock ? "L" : "Unl"));
853 retval = scsi_ioctl(STp->device, cmd, NULL);
854 if (!retval) {
855 STp->door_locked = do_lock ? ST_LOCKED_EXPLICIT : ST_UNLOCKED;
856 }
857 else {
858 STp->door_locked = ST_LOCK_FAILS;
859 }
860 return retval;
861 }
862
863
864 /* Set the internal state after reset */
865 static void reset_state(struct scsi_tape *STp)
866 {
867 int i;
868 struct st_partstat *STps;
869
870 STp->pos_unknown = 0;
871 for (i = 0; i < ST_NBR_PARTITIONS; i++) {
872 STps = &(STp->ps[i]);
873 STps->rw = ST_IDLE;
874 STps->eof = ST_NOEOF;
875 STps->at_sm = 0;
876 STps->last_block_valid = 0;
877 STps->drv_block = -1;
878 STps->drv_file = -1;
879 }
880 if (STp->can_partitions) {
881 STp->partition = find_partition(STp);
882 if (STp->partition < 0)
883 STp->partition = 0;
884 STp->new_partition = STp->partition;
885 }
886 }
887
888 /* Test if the drive is ready. Returns either one of the codes below or a negative system
889 error code. */
890 #define CHKRES_READY 0
891 #define CHKRES_NEW_SESSION 1
892 #define CHKRES_NOT_READY 2
893 #define CHKRES_NO_TAPE 3
894
895 #define MAX_ATTENTIONS 10
896
897 static int test_ready(struct scsi_tape *STp, int do_wait)
898 {
899 int attentions, waits, max_wait, scode;
900 int retval = CHKRES_READY, new_session = 0;
901 unsigned char cmd[MAX_COMMAND_SIZE];
902 struct st_request *SRpnt = NULL;
903 struct st_cmdstatus *cmdstatp = &STp->buffer->cmdstat;
904
905 max_wait = do_wait ? ST_BLOCK_SECONDS : 0;
906
907 for (attentions=waits=0; ; ) {
908 memset((void *) &cmd[0], 0, MAX_COMMAND_SIZE);
909 cmd[0] = TEST_UNIT_READY;
910 SRpnt = st_do_scsi(SRpnt, STp, cmd, 0, DMA_NONE,
911 STp->long_timeout, MAX_READY_RETRIES, 1);
912
913 if (!SRpnt) {
914 retval = (STp->buffer)->syscall_result;
915 break;
916 }
917
918 if (cmdstatp->have_sense) {
919
920 scode = cmdstatp->sense_hdr.sense_key;
921
922 if (scode == UNIT_ATTENTION) { /* New media? */
923 new_session = 1;
924 if (attentions < MAX_ATTENTIONS) {
925 attentions++;
926 continue;
927 }
928 else {
929 retval = (-EIO);
930 break;
931 }
932 }
933
934 if (scode == NOT_READY) {
935 if (waits < max_wait) {
936 if (msleep_interruptible(1000)) {
937 retval = (-EINTR);
938 break;
939 }
940 waits++;
941 continue;
942 }
943 else {
944 if ((STp->device)->scsi_level >= SCSI_2 &&
945 cmdstatp->sense_hdr.asc == 0x3a) /* Check ASC */
946 retval = CHKRES_NO_TAPE;
947 else
948 retval = CHKRES_NOT_READY;
949 break;
950 }
951 }
952 }
953
954 retval = (STp->buffer)->syscall_result;
955 if (!retval)
956 retval = new_session ? CHKRES_NEW_SESSION : CHKRES_READY;
957 break;
958 }
959
960 if (SRpnt != NULL)
961 st_release_request(SRpnt);
962 return retval;
963 }
964
965
966 /* See if the drive is ready and gather information about the tape. Return values:
967 < 0 negative error code from errno.h
968 0 drive ready
969 1 drive not ready (possibly no tape)
970 */
971 static int check_tape(struct scsi_tape *STp, struct file *filp)
972 {
973 int i, retval, new_session = 0, do_wait;
974 unsigned char cmd[MAX_COMMAND_SIZE], saved_cleaning;
975 unsigned short st_flags = filp->f_flags;
976 struct st_request *SRpnt = NULL;
977 struct st_modedef *STm;
978 struct st_partstat *STps;
979 char *name = tape_name(STp);
980 struct inode *inode = filp->f_path.dentry->d_inode;
981 int mode = TAPE_MODE(inode);
982
983 STp->ready = ST_READY;
984
985 if (mode != STp->current_mode) {
986 DEBC(printk(ST_DEB_MSG "%s: Mode change from %d to %d.\n",
987 name, STp->current_mode, mode));
988 new_session = 1;
989 STp->current_mode = mode;
990 }
991 STm = &(STp->modes[STp->current_mode]);
992
993 saved_cleaning = STp->cleaning_req;
994 STp->cleaning_req = 0;
995
996 do_wait = ((filp->f_flags & O_NONBLOCK) == 0);
997 retval = test_ready(STp, do_wait);
998
999 if (retval < 0)
1000 goto err_out;
1001
1002 if (retval == CHKRES_NEW_SESSION) {
1003 STp->pos_unknown = 0;
1004 STp->partition = STp->new_partition = 0;
1005 if (STp->can_partitions)
1006 STp->nbr_partitions = 1; /* This guess will be updated later
1007 if necessary */
1008 for (i = 0; i < ST_NBR_PARTITIONS; i++) {
1009 STps = &(STp->ps[i]);
1010 STps->rw = ST_IDLE;
1011 STps->eof = ST_NOEOF;
1012 STps->at_sm = 0;
1013 STps->last_block_valid = 0;
1014 STps->drv_block = 0;
1015 STps->drv_file = 0;
1016 }
1017 new_session = 1;
1018 }
1019 else {
1020 STp->cleaning_req |= saved_cleaning;
1021
1022 if (retval == CHKRES_NOT_READY || retval == CHKRES_NO_TAPE) {
1023 if (retval == CHKRES_NO_TAPE)
1024 STp->ready = ST_NO_TAPE;
1025 else
1026 STp->ready = ST_NOT_READY;
1027
1028 STp->density = 0; /* Clear the erroneous "residue" */
1029 STp->write_prot = 0;
1030 STp->block_size = 0;
1031 STp->ps[0].drv_file = STp->ps[0].drv_block = (-1);
1032 STp->partition = STp->new_partition = 0;
1033 STp->door_locked = ST_UNLOCKED;
1034 return CHKRES_NOT_READY;
1035 }
1036 }
1037
1038 if (STp->omit_blklims)
1039 STp->min_block = STp->max_block = (-1);
1040 else {
1041 memset((void *) &cmd[0], 0, MAX_COMMAND_SIZE);
1042 cmd[0] = READ_BLOCK_LIMITS;
1043
1044 SRpnt = st_do_scsi(SRpnt, STp, cmd, 6, DMA_FROM_DEVICE,
1045 STp->device->request_queue->rq_timeout,
1046 MAX_READY_RETRIES, 1);
1047 if (!SRpnt) {
1048 retval = (STp->buffer)->syscall_result;
1049 goto err_out;
1050 }
1051
1052 if (!SRpnt->result && !STp->buffer->cmdstat.have_sense) {
1053 STp->max_block = ((STp->buffer)->b_data[1] << 16) |
1054 ((STp->buffer)->b_data[2] << 8) | (STp->buffer)->b_data[3];
1055 STp->min_block = ((STp->buffer)->b_data[4] << 8) |
1056 (STp->buffer)->b_data[5];
1057 if ( DEB( debugging || ) !STp->inited)
1058 printk(KERN_INFO
1059 "%s: Block limits %d - %d bytes.\n", name,
1060 STp->min_block, STp->max_block);
1061 } else {
1062 STp->min_block = STp->max_block = (-1);
1063 DEBC(printk(ST_DEB_MSG "%s: Can't read block limits.\n",
1064 name));
1065 }
1066 }
1067
1068 memset((void *) &cmd[0], 0, MAX_COMMAND_SIZE);
1069 cmd[0] = MODE_SENSE;
1070 cmd[4] = 12;
1071
1072 SRpnt = st_do_scsi(SRpnt, STp, cmd, 12, DMA_FROM_DEVICE,
1073 STp->device->request_queue->rq_timeout,
1074 MAX_READY_RETRIES, 1);
1075 if (!SRpnt) {
1076 retval = (STp->buffer)->syscall_result;
1077 goto err_out;
1078 }
1079
1080 if ((STp->buffer)->syscall_result != 0) {
1081 DEBC(printk(ST_DEB_MSG "%s: No Mode Sense.\n", name));
1082 STp->block_size = ST_DEFAULT_BLOCK; /* Educated guess (?) */
1083 (STp->buffer)->syscall_result = 0; /* Prevent error propagation */
1084 STp->drv_write_prot = 0;
1085 } else {
1086 DEBC(printk(ST_DEB_MSG
1087 "%s: Mode sense. Length %d, medium %x, WBS %x, BLL %d\n",
1088 name,
1089 (STp->buffer)->b_data[0], (STp->buffer)->b_data[1],
1090 (STp->buffer)->b_data[2], (STp->buffer)->b_data[3]));
1091
1092 if ((STp->buffer)->b_data[3] >= 8) {
1093 STp->drv_buffer = ((STp->buffer)->b_data[2] >> 4) & 7;
1094 STp->density = (STp->buffer)->b_data[4];
1095 STp->block_size = (STp->buffer)->b_data[9] * 65536 +
1096 (STp->buffer)->b_data[10] * 256 + (STp->buffer)->b_data[11];
1097 DEBC(printk(ST_DEB_MSG
1098 "%s: Density %x, tape length: %x, drv buffer: %d\n",
1099 name, STp->density, (STp->buffer)->b_data[5] * 65536 +
1100 (STp->buffer)->b_data[6] * 256 + (STp->buffer)->b_data[7],
1101 STp->drv_buffer));
1102 }
1103 STp->drv_write_prot = ((STp->buffer)->b_data[2] & 0x80) != 0;
1104 }
1105 st_release_request(SRpnt);
1106 SRpnt = NULL;
1107 STp->inited = 1;
1108
1109 if (STp->block_size > 0)
1110 (STp->buffer)->buffer_blocks =
1111 (STp->buffer)->buffer_size / STp->block_size;
1112 else
1113 (STp->buffer)->buffer_blocks = 1;
1114 (STp->buffer)->buffer_bytes = (STp->buffer)->read_pointer = 0;
1115
1116 DEBC(printk(ST_DEB_MSG
1117 "%s: Block size: %d, buffer size: %d (%d blocks).\n", name,
1118 STp->block_size, (STp->buffer)->buffer_size,
1119 (STp->buffer)->buffer_blocks));
1120
1121 if (STp->drv_write_prot) {
1122 STp->write_prot = 1;
1123
1124 DEBC(printk(ST_DEB_MSG "%s: Write protected\n", name));
1125
1126 if (do_wait &&
1127 ((st_flags & O_ACCMODE) == O_WRONLY ||
1128 (st_flags & O_ACCMODE) == O_RDWR)) {
1129 retval = (-EROFS);
1130 goto err_out;
1131 }
1132 }
1133
1134 if (STp->can_partitions && STp->nbr_partitions < 1) {
1135 /* This code is reached when the device is opened for the first time
1136 after the driver has been initialized with tape in the drive and the
1137 partition support has been enabled. */
1138 DEBC(printk(ST_DEB_MSG
1139 "%s: Updating partition number in status.\n", name));
1140 if ((STp->partition = find_partition(STp)) < 0) {
1141 retval = STp->partition;
1142 goto err_out;
1143 }
1144 STp->new_partition = STp->partition;
1145 STp->nbr_partitions = 1; /* This guess will be updated when necessary */
1146 }
1147
1148 if (new_session) { /* Change the drive parameters for the new mode */
1149 STp->density_changed = STp->blksize_changed = 0;
1150 STp->compression_changed = 0;
1151 if (!(STm->defaults_for_writes) &&
1152 (retval = set_mode_densblk(STp, STm)) < 0)
1153 goto err_out;
1154
1155 if (STp->default_drvbuffer != 0xff) {
1156 if (st_int_ioctl(STp, MTSETDRVBUFFER, STp->default_drvbuffer))
1157 printk(KERN_WARNING
1158 "%s: Can't set default drive buffering to %d.\n",
1159 name, STp->default_drvbuffer);
1160 }
1161 }
1162
1163 return CHKRES_READY;
1164
1165 err_out:
1166 return retval;
1167 }
1168
1169
1170 /* Open the device. Needs to take the BKL only because of incrementing the SCSI host
1171 module count. */
1172 static int st_open(struct inode *inode, struct file *filp)
1173 {
1174 int i, retval = (-EIO);
1175 struct scsi_tape *STp;
1176 struct st_partstat *STps;
1177 int dev = TAPE_NR(inode);
1178 char *name;
1179
1180 lock_kernel();
1181 /*
1182 * We really want to do nonseekable_open(inode, filp); here, but some
1183 * versions of tar incorrectly call lseek on tapes and bail out if that
1184 * fails. So we disallow pread() and pwrite(), but permit lseeks.
1185 */
1186 filp->f_mode &= ~(FMODE_PREAD | FMODE_PWRITE);
1187
1188 if (!(STp = scsi_tape_get(dev))) {
1189 unlock_kernel();
1190 return -ENXIO;
1191 }
1192
1193 write_lock(&st_dev_arr_lock);
1194 filp->private_data = STp;
1195 name = tape_name(STp);
1196
1197 if (STp->in_use) {
1198 write_unlock(&st_dev_arr_lock);
1199 scsi_tape_put(STp);
1200 unlock_kernel();
1201 DEB( printk(ST_DEB_MSG "%s: Device already in use.\n", name); )
1202 return (-EBUSY);
1203 }
1204
1205 STp->in_use = 1;
1206 write_unlock(&st_dev_arr_lock);
1207 STp->rew_at_close = STp->autorew_dev = (iminor(inode) & 0x80) == 0;
1208
1209 if (!scsi_block_when_processing_errors(STp->device)) {
1210 retval = (-ENXIO);
1211 goto err_out;
1212 }
1213
1214 /* See that we have at least a one page buffer available */
1215 if (!enlarge_buffer(STp->buffer, PAGE_SIZE, STp->restr_dma)) {
1216 printk(KERN_WARNING "%s: Can't allocate one page tape buffer.\n",
1217 name);
1218 retval = (-EOVERFLOW);
1219 goto err_out;
1220 }
1221
1222 (STp->buffer)->cleared = 0;
1223 (STp->buffer)->writing = 0;
1224 (STp->buffer)->syscall_result = 0;
1225
1226 STp->write_prot = ((filp->f_flags & O_ACCMODE) == O_RDONLY);
1227
1228 STp->dirty = 0;
1229 for (i = 0; i < ST_NBR_PARTITIONS; i++) {
1230 STps = &(STp->ps[i]);
1231 STps->rw = ST_IDLE;
1232 }
1233 STp->try_dio_now = STp->try_dio;
1234 STp->recover_count = 0;
1235 DEB( STp->nbr_waits = STp->nbr_finished = 0;
1236 STp->nbr_requests = STp->nbr_dio = STp->nbr_pages = 0; )
1237
1238 retval = check_tape(STp, filp);
1239 if (retval < 0)
1240 goto err_out;
1241 if ((filp->f_flags & O_NONBLOCK) == 0 &&
1242 retval != CHKRES_READY) {
1243 if (STp->ready == NO_TAPE)
1244 retval = (-ENOMEDIUM);
1245 else
1246 retval = (-EIO);
1247 goto err_out;
1248 }
1249 unlock_kernel();
1250 return 0;
1251
1252 err_out:
1253 normalize_buffer(STp->buffer);
1254 STp->in_use = 0;
1255 scsi_tape_put(STp);
1256 unlock_kernel();
1257 return retval;
1258
1259 }
1260
1261
1262 /* Flush the tape buffer before close */
1263 static int st_flush(struct file *filp, fl_owner_t id)
1264 {
1265 int result = 0, result2;
1266 unsigned char cmd[MAX_COMMAND_SIZE];
1267 struct st_request *SRpnt;
1268 struct scsi_tape *STp = filp->private_data;
1269 struct st_modedef *STm = &(STp->modes[STp->current_mode]);
1270 struct st_partstat *STps = &(STp->ps[STp->partition]);
1271 char *name = tape_name(STp);
1272
1273 if (file_count(filp) > 1)
1274 return 0;
1275
1276 if (STps->rw == ST_WRITING && !STp->pos_unknown) {
1277 result = st_flush_write_buffer(STp);
1278 if (result != 0 && result != (-ENOSPC))
1279 goto out;
1280 }
1281
1282 if (STp->can_partitions &&
1283 (result2 = switch_partition(STp)) < 0) {
1284 DEBC(printk(ST_DEB_MSG
1285 "%s: switch_partition at close failed.\n", name));
1286 if (result == 0)
1287 result = result2;
1288 goto out;
1289 }
1290
1291 DEBC( if (STp->nbr_requests)
1292 printk(KERN_DEBUG "%s: Number of r/w requests %d, dio used in %d, pages %d.\n",
1293 name, STp->nbr_requests, STp->nbr_dio, STp->nbr_pages));
1294
1295 if (STps->rw == ST_WRITING && !STp->pos_unknown) {
1296 struct st_cmdstatus *cmdstatp = &STp->buffer->cmdstat;
1297
1298 DEBC(printk(ST_DEB_MSG "%s: Async write waits %d, finished %d.\n",
1299 name, STp->nbr_waits, STp->nbr_finished);
1300 )
1301
1302 memset(cmd, 0, MAX_COMMAND_SIZE);
1303 cmd[0] = WRITE_FILEMARKS;
1304 cmd[4] = 1 + STp->two_fm;
1305
1306 SRpnt = st_do_scsi(NULL, STp, cmd, 0, DMA_NONE,
1307 STp->device->request_queue->rq_timeout,
1308 MAX_WRITE_RETRIES, 1);
1309 if (!SRpnt) {
1310 result = (STp->buffer)->syscall_result;
1311 goto out;
1312 }
1313
1314 if (STp->buffer->syscall_result == 0 ||
1315 (cmdstatp->have_sense && !cmdstatp->deferred &&
1316 (cmdstatp->flags & SENSE_EOM) &&
1317 (cmdstatp->sense_hdr.sense_key == NO_SENSE ||
1318 cmdstatp->sense_hdr.sense_key == RECOVERED_ERROR) &&
1319 (!cmdstatp->remainder_valid || cmdstatp->uremainder64 == 0))) {
1320 /* Write successful at EOM */
1321 st_release_request(SRpnt);
1322 SRpnt = NULL;
1323 if (STps->drv_file >= 0)
1324 STps->drv_file++;
1325 STps->drv_block = 0;
1326 if (STp->two_fm)
1327 cross_eof(STp, 0);
1328 STps->eof = ST_FM;
1329 }
1330 else { /* Write error */
1331 st_release_request(SRpnt);
1332 SRpnt = NULL;
1333 printk(KERN_ERR "%s: Error on write filemark.\n", name);
1334 if (result == 0)
1335 result = (-EIO);
1336 }
1337
1338 DEBC(printk(ST_DEB_MSG "%s: Buffer flushed, %d EOF(s) written\n",
1339 name, cmd[4]));
1340 } else if (!STp->rew_at_close) {
1341 STps = &(STp->ps[STp->partition]);
1342 if (!STm->sysv || STps->rw != ST_READING) {
1343 if (STp->can_bsr)
1344 result = flush_buffer(STp, 0);
1345 else if (STps->eof == ST_FM_HIT) {
1346 result = cross_eof(STp, 0);
1347 if (result) {
1348 if (STps->drv_file >= 0)
1349 STps->drv_file++;
1350 STps->drv_block = 0;
1351 STps->eof = ST_FM;
1352 } else
1353 STps->eof = ST_NOEOF;
1354 }
1355 } else if ((STps->eof == ST_NOEOF &&
1356 !(result = cross_eof(STp, 1))) ||
1357 STps->eof == ST_FM_HIT) {
1358 if (STps->drv_file >= 0)
1359 STps->drv_file++;
1360 STps->drv_block = 0;
1361 STps->eof = ST_FM;
1362 }
1363 }
1364
1365 out:
1366 if (STp->rew_at_close) {
1367 result2 = st_int_ioctl(STp, MTREW, 1);
1368 if (result == 0)
1369 result = result2;
1370 }
1371 return result;
1372 }
1373
1374
1375 /* Close the device and release it. BKL is not needed: this is the only thread
1376 accessing this tape. */
1377 static int st_release(struct inode *inode, struct file *filp)
1378 {
1379 int result = 0;
1380 struct scsi_tape *STp = filp->private_data;
1381
1382 if (STp->door_locked == ST_LOCKED_AUTO)
1383 do_door_lock(STp, 0);
1384
1385 normalize_buffer(STp->buffer);
1386 write_lock(&st_dev_arr_lock);
1387 STp->in_use = 0;
1388 write_unlock(&st_dev_arr_lock);
1389 scsi_tape_put(STp);
1390
1391 return result;
1392 }
1393
1394 /* The checks common to both reading and writing */
1395 static ssize_t rw_checks(struct scsi_tape *STp, struct file *filp, size_t count)
1396 {
1397 ssize_t retval = 0;
1398
1399 /*
1400 * If we are in the middle of error recovery, don't let anyone
1401 * else try and use this device. Also, if error recovery fails, it
1402 * may try and take the device offline, in which case all further
1403 * access to the device is prohibited.
1404 */
1405 if (!scsi_block_when_processing_errors(STp->device)) {
1406 retval = (-ENXIO);
1407 goto out;
1408 }
1409
1410 if (STp->ready != ST_READY) {
1411 if (STp->ready == ST_NO_TAPE)
1412 retval = (-ENOMEDIUM);
1413 else
1414 retval = (-EIO);
1415 goto out;
1416 }
1417
1418 if (! STp->modes[STp->current_mode].defined) {
1419 retval = (-ENXIO);
1420 goto out;
1421 }
1422
1423
1424 /*
1425 * If there was a bus reset, block further access
1426 * to this device.
1427 */
1428 if (STp->pos_unknown) {
1429 retval = (-EIO);
1430 goto out;
1431 }
1432
1433 if (count == 0)
1434 goto out;
1435
1436 DEB(
1437 if (!STp->in_use) {
1438 printk(ST_DEB_MSG "%s: Incorrect device.\n", tape_name(STp));
1439 retval = (-EIO);
1440 goto out;
1441 } ) /* end DEB */
1442
1443 if (STp->can_partitions &&
1444 (retval = switch_partition(STp)) < 0)
1445 goto out;
1446
1447 if (STp->block_size == 0 && STp->max_block > 0 &&
1448 (count < STp->min_block || count > STp->max_block)) {
1449 retval = (-EINVAL);
1450 goto out;
1451 }
1452
1453 if (STp->do_auto_lock && STp->door_locked == ST_UNLOCKED &&
1454 !do_door_lock(STp, 1))
1455 STp->door_locked = ST_LOCKED_AUTO;
1456
1457 out:
1458 return retval;
1459 }
1460
1461
1462 static int setup_buffering(struct scsi_tape *STp, const char __user *buf,
1463 size_t count, int is_read)
1464 {
1465 int i, bufsize, retval = 0;
1466 struct st_buffer *STbp = STp->buffer;
1467
1468 if (is_read)
1469 i = STp->try_dio_now && try_rdio;
1470 else
1471 i = STp->try_dio_now && try_wdio;
1472
1473 if (i && ((unsigned long)buf & queue_dma_alignment(
1474 STp->device->request_queue)) == 0) {
1475 i = sgl_map_user_pages(STbp, STbp->use_sg, (unsigned long)buf,
1476 count, (is_read ? READ : WRITE));
1477 if (i > 0) {
1478 STbp->do_dio = i;
1479 STbp->buffer_bytes = 0; /* can be used as transfer counter */
1480 }
1481 else
1482 STbp->do_dio = 0; /* fall back to buffering with any error */
1483 STbp->sg_segs = STbp->do_dio;
1484 DEB(
1485 if (STbp->do_dio) {
1486 STp->nbr_dio++;
1487 STp->nbr_pages += STbp->do_dio;
1488 }
1489 )
1490 } else
1491 STbp->do_dio = 0;
1492 DEB( STp->nbr_requests++; )
1493
1494 if (!STbp->do_dio) {
1495 if (STp->block_size)
1496 bufsize = STp->block_size > st_fixed_buffer_size ?
1497 STp->block_size : st_fixed_buffer_size;
1498 else {
1499 bufsize = count;
1500 /* Make sure that data from previous user is not leaked even if
1501 HBA does not return correct residual */
1502 if (is_read && STp->sili && !STbp->cleared)
1503 clear_buffer(STbp);
1504 }
1505
1506 if (bufsize > STbp->buffer_size &&
1507 !enlarge_buffer(STbp, bufsize, STp->restr_dma)) {
1508 printk(KERN_WARNING "%s: Can't allocate %d byte tape buffer.\n",
1509 tape_name(STp), bufsize);
1510 retval = (-EOVERFLOW);
1511 goto out;
1512 }
1513 if (STp->block_size)
1514 STbp->buffer_blocks = bufsize / STp->block_size;
1515 }
1516
1517 out:
1518 return retval;
1519 }
1520
1521
1522 /* Can be called more than once after each setup_buffer() */
1523 static void release_buffering(struct scsi_tape *STp, int is_read)
1524 {
1525 struct st_buffer *STbp;
1526
1527 STbp = STp->buffer;
1528 if (STbp->do_dio) {
1529 sgl_unmap_user_pages(STbp, STbp->do_dio, is_read);
1530 STbp->do_dio = 0;
1531 STbp->sg_segs = 0;
1532 }
1533 }
1534
1535
1536 /* Write command */
1537 static ssize_t
1538 st_write(struct file *filp, const char __user *buf, size_t count, loff_t * ppos)
1539 {
1540 ssize_t total;
1541 ssize_t i, do_count, blks, transfer;
1542 ssize_t retval;
1543 int undone, retry_eot = 0, scode;
1544 int async_write;
1545 unsigned char cmd[MAX_COMMAND_SIZE];
1546 const char __user *b_point;
1547 struct st_request *SRpnt = NULL;
1548 struct scsi_tape *STp = filp->private_data;
1549 struct st_modedef *STm;
1550 struct st_partstat *STps;
1551 struct st_buffer *STbp;
1552 char *name = tape_name(STp);
1553
1554 if (mutex_lock_interruptible(&STp->lock))
1555 return -ERESTARTSYS;
1556
1557 retval = rw_checks(STp, filp, count);
1558 if (retval || count == 0)
1559 goto out;
1560
1561 /* Write must be integral number of blocks */
1562 if (STp->block_size != 0 && (count % STp->block_size) != 0) {
1563 printk(KERN_WARNING "%s: Write not multiple of tape block size.\n",
1564 name);
1565 retval = (-EINVAL);
1566 goto out;
1567 }
1568
1569 STm = &(STp->modes[STp->current_mode]);
1570 STps = &(STp->ps[STp->partition]);
1571
1572 if (STp->write_prot) {
1573 retval = (-EACCES);
1574 goto out;
1575 }
1576
1577
1578 if (STps->rw == ST_READING) {
1579 retval = flush_buffer(STp, 0);
1580 if (retval)
1581 goto out;
1582 STps->rw = ST_WRITING;
1583 } else if (STps->rw != ST_WRITING &&
1584 STps->drv_file == 0 && STps->drv_block == 0) {
1585 if ((retval = set_mode_densblk(STp, STm)) < 0)
1586 goto out;
1587 if (STm->default_compression != ST_DONT_TOUCH &&
1588 !(STp->compression_changed)) {
1589 if (st_compression(STp, (STm->default_compression == ST_YES))) {
1590 printk(KERN_WARNING "%s: Can't set default compression.\n",
1591 name);
1592 if (modes_defined) {
1593 retval = (-EINVAL);
1594 goto out;
1595 }
1596 }
1597 }
1598 }
1599
1600 STbp = STp->buffer;
1601 i = write_behind_check(STp);
1602 if (i) {
1603 if (i == -ENOSPC)
1604 STps->eof = ST_EOM_OK;
1605 else
1606 STps->eof = ST_EOM_ERROR;
1607 }
1608
1609 if (STps->eof == ST_EOM_OK) {
1610 STps->eof = ST_EOD_1; /* allow next write */
1611 retval = (-ENOSPC);
1612 goto out;
1613 }
1614 else if (STps->eof == ST_EOM_ERROR) {
1615 retval = (-EIO);
1616 goto out;
1617 }
1618
1619 /* Check the buffer readability in cases where copy_user might catch
1620 the problems after some tape movement. */
1621 if (STp->block_size != 0 &&
1622 !STbp->do_dio &&
1623 (copy_from_user(&i, buf, 1) != 0 ||
1624 copy_from_user(&i, buf + count - 1, 1) != 0)) {
1625 retval = (-EFAULT);
1626 goto out;
1627 }
1628
1629 retval = setup_buffering(STp, buf, count, 0);
1630 if (retval)
1631 goto out;
1632
1633 total = count;
1634
1635 memset(cmd, 0, MAX_COMMAND_SIZE);
1636 cmd[0] = WRITE_6;
1637 cmd[1] = (STp->block_size != 0);
1638
1639 STps->rw = ST_WRITING;
1640
1641 b_point = buf;
1642 while (count > 0 && !retry_eot) {
1643
1644 if (STbp->do_dio) {
1645 do_count = count;
1646 }
1647 else {
1648 if (STp->block_size == 0)
1649 do_count = count;
1650 else {
1651 do_count = STbp->buffer_blocks * STp->block_size -
1652 STbp->buffer_bytes;
1653 if (do_count > count)
1654 do_count = count;
1655 }
1656
1657 i = append_to_buffer(b_point, STbp, do_count);
1658 if (i) {
1659 retval = i;
1660 goto out;
1661 }
1662 }
1663 count -= do_count;
1664 b_point += do_count;
1665
1666 async_write = STp->block_size == 0 && !STbp->do_dio &&
1667 STm->do_async_writes && STps->eof < ST_EOM_OK;
1668
1669 if (STp->block_size != 0 && STm->do_buffer_writes &&
1670 !(STp->try_dio_now && try_wdio) && STps->eof < ST_EOM_OK &&
1671 STbp->buffer_bytes < STbp->buffer_size) {
1672 STp->dirty = 1;
1673 /* Don't write a buffer that is not full enough. */
1674 if (!async_write && count == 0)
1675 break;
1676 }
1677
1678 retry_write:
1679 if (STp->block_size == 0)
1680 blks = transfer = do_count;
1681 else {
1682 if (!STbp->do_dio)
1683 blks = STbp->buffer_bytes;
1684 else
1685 blks = do_count;
1686 blks /= STp->block_size;
1687 transfer = blks * STp->block_size;
1688 }
1689 cmd[2] = blks >> 16;
1690 cmd[3] = blks >> 8;
1691 cmd[4] = blks;
1692
1693 SRpnt = st_do_scsi(SRpnt, STp, cmd, transfer, DMA_TO_DEVICE,
1694 STp->device->request_queue->rq_timeout,
1695 MAX_WRITE_RETRIES, !async_write);
1696 if (!SRpnt) {
1697 retval = STbp->syscall_result;
1698 goto out;
1699 }
1700 if (async_write && !STbp->syscall_result) {
1701 STbp->writing = transfer;
1702 STp->dirty = !(STbp->writing ==
1703 STbp->buffer_bytes);
1704 SRpnt = NULL; /* Prevent releasing this request! */
1705 DEB( STp->write_pending = 1; )
1706 break;
1707 }
1708
1709 if (STbp->syscall_result != 0) {
1710 struct st_cmdstatus *cmdstatp = &STp->buffer->cmdstat;
1711
1712 DEBC(printk(ST_DEB_MSG "%s: Error on write:\n", name));
1713 if (cmdstatp->have_sense && (cmdstatp->flags & SENSE_EOM)) {
1714 scode = cmdstatp->sense_hdr.sense_key;
1715 if (cmdstatp->remainder_valid)
1716 undone = (int)cmdstatp->uremainder64;
1717 else if (STp->block_size == 0 &&
1718 scode == VOLUME_OVERFLOW)
1719 undone = transfer;
1720 else
1721 undone = 0;
1722 if (STp->block_size != 0)
1723 undone *= STp->block_size;
1724 if (undone <= do_count) {
1725 /* Only data from this write is not written */
1726 count += undone;
1727 b_point -= undone;
1728 do_count -= undone;
1729 if (STp->block_size)
1730 blks = (transfer - undone) / STp->block_size;
1731 STps->eof = ST_EOM_OK;
1732 /* Continue in fixed block mode if all written
1733 in this request but still something left to write
1734 (retval left to zero)
1735 */
1736 if (STp->block_size == 0 ||
1737 undone > 0 || count == 0)
1738 retval = (-ENOSPC); /* EOM within current request */
1739 DEBC(printk(ST_DEB_MSG
1740 "%s: EOM with %d bytes unwritten.\n",
1741 name, (int)count));
1742 } else {
1743 /* EOT within data buffered earlier (possible only
1744 in fixed block mode without direct i/o) */
1745 if (!retry_eot && !cmdstatp->deferred &&
1746 (scode == NO_SENSE || scode == RECOVERED_ERROR)) {
1747 move_buffer_data(STp->buffer, transfer - undone);
1748 retry_eot = 1;
1749 if (STps->drv_block >= 0) {
1750 STps->drv_block += (transfer - undone) /
1751 STp->block_size;
1752 }
1753 STps->eof = ST_EOM_OK;
1754 DEBC(printk(ST_DEB_MSG
1755 "%s: Retry write of %d bytes at EOM.\n",
1756 name, STp->buffer->buffer_bytes));
1757 goto retry_write;
1758 }
1759 else {
1760 /* Either error within data buffered by driver or
1761 failed retry */
1762 count -= do_count;
1763 blks = do_count = 0;
1764 STps->eof = ST_EOM_ERROR;
1765 STps->drv_block = (-1); /* Too cautious? */
1766 retval = (-EIO); /* EOM for old data */
1767 DEBC(printk(ST_DEB_MSG
1768 "%s: EOM with lost data.\n",
1769 name));
1770 }
1771 }
1772 } else {
1773 count += do_count;
1774 STps->drv_block = (-1); /* Too cautious? */
1775 retval = STbp->syscall_result;
1776 }
1777
1778 }
1779
1780 if (STps->drv_block >= 0) {
1781 if (STp->block_size == 0)
1782 STps->drv_block += (do_count > 0);
1783 else
1784 STps->drv_block += blks;
1785 }
1786
1787 STbp->buffer_bytes = 0;
1788 STp->dirty = 0;
1789
1790 if (retval || retry_eot) {
1791 if (count < total)
1792 retval = total - count;
1793 goto out;
1794 }
1795 }
1796
1797 if (STps->eof == ST_EOD_1)
1798 STps->eof = ST_EOM_OK;
1799 else if (STps->eof != ST_EOM_OK)
1800 STps->eof = ST_NOEOF;
1801 retval = total - count;
1802
1803 out:
1804 if (SRpnt != NULL)
1805 st_release_request(SRpnt);
1806 release_buffering(STp, 0);
1807 mutex_unlock(&STp->lock);
1808
1809 return retval;
1810 }
1811
1812 /* Read data from the tape. Returns zero in the normal case, one if the
1813 eof status has changed, and the negative error code in case of a
1814 fatal error. Otherwise updates the buffer and the eof state.
1815
1816 Does release user buffer mapping if it is set.
1817 */
1818 static long read_tape(struct scsi_tape *STp, long count,
1819 struct st_request ** aSRpnt)
1820 {
1821 int transfer, blks, bytes;
1822 unsigned char cmd[MAX_COMMAND_SIZE];
1823 struct st_request *SRpnt;
1824 struct st_modedef *STm;
1825 struct st_partstat *STps;
1826 struct st_buffer *STbp;
1827 int retval = 0;
1828 char *name = tape_name(STp);
1829
1830 if (count == 0)
1831 return 0;
1832
1833 STm = &(STp->modes[STp->current_mode]);
1834 STps = &(STp->ps[STp->partition]);
1835 if (STps->eof == ST_FM_HIT)
1836 return 1;
1837 STbp = STp->buffer;
1838
1839 if (STp->block_size == 0)
1840 blks = bytes = count;
1841 else {
1842 if (!(STp->try_dio_now && try_rdio) && STm->do_read_ahead) {
1843 blks = (STp->buffer)->buffer_blocks;
1844 bytes = blks * STp->block_size;
1845 } else {
1846 bytes = count;
1847 if (!STbp->do_dio && bytes > (STp->buffer)->buffer_size)
1848 bytes = (STp->buffer)->buffer_size;
1849 blks = bytes / STp->block_size;
1850 bytes = blks * STp->block_size;
1851 }
1852 }
1853
1854 memset(cmd, 0, MAX_COMMAND_SIZE);
1855 cmd[0] = READ_6;
1856 cmd[1] = (STp->block_size != 0);
1857 if (!cmd[1] && STp->sili)
1858 cmd[1] |= 2;
1859 cmd[2] = blks >> 16;
1860 cmd[3] = blks >> 8;
1861 cmd[4] = blks;
1862
1863 SRpnt = *aSRpnt;
1864 SRpnt = st_do_scsi(SRpnt, STp, cmd, bytes, DMA_FROM_DEVICE,
1865 STp->device->request_queue->rq_timeout,
1866 MAX_RETRIES, 1);
1867 release_buffering(STp, 1);
1868 *aSRpnt = SRpnt;
1869 if (!SRpnt)
1870 return STbp->syscall_result;
1871
1872 STbp->read_pointer = 0;
1873 STps->at_sm = 0;
1874
1875 /* Something to check */
1876 if (STbp->syscall_result) {
1877 struct st_cmdstatus *cmdstatp = &STp->buffer->cmdstat;
1878
1879 retval = 1;
1880 DEBC(printk(ST_DEB_MSG "%s: Sense: %2x %2x %2x %2x %2x %2x %2x %2x\n",
1881 name,
1882 SRpnt->sense[0], SRpnt->sense[1],
1883 SRpnt->sense[2], SRpnt->sense[3],
1884 SRpnt->sense[4], SRpnt->sense[5],
1885 SRpnt->sense[6], SRpnt->sense[7]));
1886 if (cmdstatp->have_sense) {
1887
1888 if (cmdstatp->sense_hdr.sense_key == BLANK_CHECK)
1889 cmdstatp->flags &= 0xcf; /* No need for EOM in this case */
1890
1891 if (cmdstatp->flags != 0) { /* EOF, EOM, or ILI */
1892 /* Compute the residual count */
1893 if (cmdstatp->remainder_valid)
1894 transfer = (int)cmdstatp->uremainder64;
1895 else
1896 transfer = 0;
1897 if (STp->block_size == 0 &&
1898 cmdstatp->sense_hdr.sense_key == MEDIUM_ERROR)
1899 transfer = bytes;
1900
1901 if (cmdstatp->flags & SENSE_ILI) { /* ILI */
1902 if (STp->block_size == 0) {
1903 if (transfer <= 0) {
1904 if (transfer < 0)
1905 printk(KERN_NOTICE
1906 "%s: Failed to read %d byte block with %d byte transfer.\n",
1907 name, bytes - transfer, bytes);
1908 if (STps->drv_block >= 0)
1909 STps->drv_block += 1;
1910 STbp->buffer_bytes = 0;
1911 return (-ENOMEM);
1912 }
1913 STbp->buffer_bytes = bytes - transfer;
1914 } else {
1915 st_release_request(SRpnt);
1916 SRpnt = *aSRpnt = NULL;
1917 if (transfer == blks) { /* We did not get anything, error */
1918 printk(KERN_NOTICE "%s: Incorrect block size.\n", name);
1919 if (STps->drv_block >= 0)
1920 STps->drv_block += blks - transfer + 1;
1921 st_int_ioctl(STp, MTBSR, 1);
1922 return (-EIO);
1923 }
1924 /* We have some data, deliver it */
1925 STbp->buffer_bytes = (blks - transfer) *
1926 STp->block_size;
1927 DEBC(printk(ST_DEB_MSG
1928 "%s: ILI but enough data received %ld %d.\n",
1929 name, count, STbp->buffer_bytes));
1930 if (STps->drv_block >= 0)
1931 STps->drv_block += 1;
1932 if (st_int_ioctl(STp, MTBSR, 1))
1933 return (-EIO);
1934 }
1935 } else if (cmdstatp->flags & SENSE_FMK) { /* FM overrides EOM */
1936 if (STps->eof != ST_FM_HIT)
1937 STps->eof = ST_FM_HIT;
1938 else
1939 STps->eof = ST_EOD_2;
1940 if (STp->block_size == 0)
1941 STbp->buffer_bytes = 0;
1942 else
1943 STbp->buffer_bytes =
1944 bytes - transfer * STp->block_size;
1945 DEBC(printk(ST_DEB_MSG
1946 "%s: EOF detected (%d bytes read).\n",
1947 name, STbp->buffer_bytes));
1948 } else if (cmdstatp->flags & SENSE_EOM) {
1949 if (STps->eof == ST_FM)
1950 STps->eof = ST_EOD_1;
1951 else
1952 STps->eof = ST_EOM_OK;
1953 if (STp->block_size == 0)
1954 STbp->buffer_bytes = bytes - transfer;
1955 else
1956 STbp->buffer_bytes =
1957 bytes - transfer * STp->block_size;
1958
1959 DEBC(printk(ST_DEB_MSG "%s: EOM detected (%d bytes read).\n",
1960 name, STbp->buffer_bytes));
1961 }
1962 }
1963 /* end of EOF, EOM, ILI test */
1964 else { /* nonzero sense key */
1965 DEBC(printk(ST_DEB_MSG
1966 "%s: Tape error while reading.\n", name));
1967 STps->drv_block = (-1);
1968 if (STps->eof == ST_FM &&
1969 cmdstatp->sense_hdr.sense_key == BLANK_CHECK) {
1970 DEBC(printk(ST_DEB_MSG
1971 "%s: Zero returned for first BLANK CHECK after EOF.\n",
1972 name));
1973 STps->eof = ST_EOD_2; /* First BLANK_CHECK after FM */
1974 } else /* Some other extended sense code */
1975 retval = (-EIO);
1976 }
1977
1978 if (STbp->buffer_bytes < 0) /* Caused by bogus sense data */
1979 STbp->buffer_bytes = 0;
1980 }
1981 /* End of extended sense test */
1982 else { /* Non-extended sense */
1983 retval = STbp->syscall_result;
1984 }
1985
1986 }
1987 /* End of error handling */
1988 else { /* Read successful */
1989 STbp->buffer_bytes = bytes;
1990 if (STp->sili) /* In fixed block mode residual is always zero here */
1991 STbp->buffer_bytes -= STp->buffer->cmdstat.residual;
1992 }
1993
1994 if (STps->drv_block >= 0) {
1995 if (STp->block_size == 0)
1996 STps->drv_block++;
1997 else
1998 STps->drv_block += STbp->buffer_bytes / STp->block_size;
1999 }
2000 return retval;
2001 }
2002
2003
2004 /* Read command */
2005 static ssize_t
2006 st_read(struct file *filp, char __user *buf, size_t count, loff_t * ppos)
2007 {
2008 ssize_t total;
2009 ssize_t retval = 0;
2010 ssize_t i, transfer;
2011 int special, do_dio = 0;
2012 struct st_request *SRpnt = NULL;
2013 struct scsi_tape *STp = filp->private_data;
2014 struct st_modedef *STm;
2015 struct st_partstat *STps;
2016 struct st_buffer *STbp = STp->buffer;
2017 DEB( char *name = tape_name(STp); )
2018
2019 if (mutex_lock_interruptible(&STp->lock))
2020 return -ERESTARTSYS;
2021
2022 retval = rw_checks(STp, filp, count);
2023 if (retval || count == 0)
2024 goto out;
2025
2026 STm = &(STp->modes[STp->current_mode]);
2027 if (STp->block_size != 0 && (count % STp->block_size) != 0) {
2028 if (!STm->do_read_ahead) {
2029 retval = (-EINVAL); /* Read must be integral number of blocks */
2030 goto out;
2031 }
2032 STp->try_dio_now = 0; /* Direct i/o can't handle split blocks */
2033 }
2034
2035 STps = &(STp->ps[STp->partition]);
2036 if (STps->rw == ST_WRITING) {
2037 retval = flush_buffer(STp, 0);
2038 if (retval)
2039 goto out;
2040 STps->rw = ST_READING;
2041 }
2042 DEB(
2043 if (debugging && STps->eof != ST_NOEOF)
2044 printk(ST_DEB_MSG "%s: EOF/EOM flag up (%d). Bytes %d\n", name,
2045 STps->eof, STbp->buffer_bytes);
2046 ) /* end DEB */
2047
2048 retval = setup_buffering(STp, buf, count, 1);
2049 if (retval)
2050 goto out;
2051 do_dio = STbp->do_dio;
2052
2053 if (STbp->buffer_bytes == 0 &&
2054 STps->eof >= ST_EOD_1) {
2055 if (STps->eof < ST_EOD) {
2056 STps->eof += 1;
2057 retval = 0;
2058 goto out;
2059 }
2060 retval = (-EIO); /* EOM or Blank Check */
2061 goto out;
2062 }
2063
2064 if (do_dio) {
2065 /* Check the buffer writability before any tape movement. Don't alter
2066 buffer data. */
2067 if (copy_from_user(&i, buf, 1) != 0 ||
2068 copy_to_user(buf, &i, 1) != 0 ||
2069 copy_from_user(&i, buf + count - 1, 1) != 0 ||
2070 copy_to_user(buf + count - 1, &i, 1) != 0) {
2071 retval = (-EFAULT);
2072 goto out;
2073 }
2074 }
2075
2076 STps->rw = ST_READING;
2077
2078
2079 /* Loop until enough data in buffer or a special condition found */
2080 for (total = 0, special = 0; total < count && !special;) {
2081
2082 /* Get new data if the buffer is empty */
2083 if (STbp->buffer_bytes == 0) {
2084 special = read_tape(STp, count - total, &SRpnt);
2085 if (special < 0) { /* No need to continue read */
2086 retval = special;
2087 goto out;
2088 }
2089 }
2090
2091 /* Move the data from driver buffer to user buffer */
2092 if (STbp->buffer_bytes > 0) {
2093 DEB(
2094 if (debugging && STps->eof != ST_NOEOF)
2095 printk(ST_DEB_MSG
2096 "%s: EOF up (%d). Left %d, needed %d.\n", name,
2097 STps->eof, STbp->buffer_bytes,
2098 (int)(count - total));
2099 ) /* end DEB */
2100 transfer = STbp->buffer_bytes < count - total ?
2101 STbp->buffer_bytes : count - total;
2102 if (!do_dio) {
2103 i = from_buffer(STbp, buf, transfer);
2104 if (i) {
2105 retval = i;
2106 goto out;
2107 }
2108 }
2109 buf += transfer;
2110 total += transfer;
2111 }
2112
2113 if (STp->block_size == 0)
2114 break; /* Read only one variable length block */
2115
2116 } /* for (total = 0, special = 0;
2117 total < count && !special; ) */
2118
2119 /* Change the eof state if no data from tape or buffer */
2120 if (total == 0) {
2121 if (STps->eof == ST_FM_HIT) {
2122 STps->eof = ST_FM;
2123 STps->drv_block = 0;
2124 if (STps->drv_file >= 0)
2125 STps->drv_file++;
2126 } else if (STps->eof == ST_EOD_1) {
2127 STps->eof = ST_EOD_2;
2128 STps->drv_block = 0;
2129 if (STps->drv_file >= 0)
2130 STps->drv_file++;
2131 } else if (STps->eof == ST_EOD_2)
2132 STps->eof = ST_EOD;
2133 } else if (STps->eof == ST_FM)
2134 STps->eof = ST_NOEOF;
2135 retval = total;
2136
2137 out:
2138 if (SRpnt != NULL) {
2139 st_release_request(SRpnt);
2140 SRpnt = NULL;
2141 }
2142 if (do_dio) {
2143 release_buffering(STp, 1);
2144 STbp->buffer_bytes = 0;
2145 }
2146 mutex_unlock(&STp->lock);
2147
2148 return retval;
2149 }
2150
2151
2152
2153 DEB(
2154 /* Set the driver options */
2155 static void st_log_options(struct scsi_tape * STp, struct st_modedef * STm, char *name)
2156 {
2157 if (debugging) {
2158 printk(KERN_INFO
2159 "%s: Mode %d options: buffer writes: %d, async writes: %d, read ahead: %d\n",
2160 name, STp->current_mode, STm->do_buffer_writes, STm->do_async_writes,
2161 STm->do_read_ahead);
2162 printk(KERN_INFO
2163 "%s: can bsr: %d, two FMs: %d, fast mteom: %d, auto lock: %d,\n",
2164 name, STp->can_bsr, STp->two_fm, STp->fast_mteom, STp->do_auto_lock);
2165 printk(KERN_INFO
2166 "%s: defs for wr: %d, no block limits: %d, partitions: %d, s2 log: %d\n",
2167 name, STm->defaults_for_writes, STp->omit_blklims, STp->can_partitions,
2168 STp->scsi2_logical);
2169 printk(KERN_INFO
2170 "%s: sysv: %d nowait: %d sili: %d\n", name, STm->sysv, STp->immediate,
2171 STp->sili);
2172 printk(KERN_INFO "%s: debugging: %d\n",
2173 name, debugging);
2174 }
2175 }
2176 )
2177
2178
2179 static int st_set_options(struct scsi_tape *STp, long options)
2180 {
2181 int value;
2182 long code;
2183 struct st_modedef *STm;
2184 char *name = tape_name(STp);
2185 struct cdev *cd0, *cd1;
2186
2187 STm = &(STp->modes[STp->current_mode]);
2188 if (!STm->defined) {
2189 cd0 = STm->cdevs[0]; cd1 = STm->cdevs[1];
2190 memcpy(STm, &(STp->modes[0]), sizeof(struct st_modedef));
2191 STm->cdevs[0] = cd0; STm->cdevs[1] = cd1;
2192 modes_defined = 1;
2193 DEBC(printk(ST_DEB_MSG
2194 "%s: Initialized mode %d definition from mode 0\n",
2195 name, STp->current_mode));
2196 }
2197
2198 code = options & MT_ST_OPTIONS;
2199 if (code == MT_ST_BOOLEANS) {
2200 STm->do_buffer_writes = (options & MT_ST_BUFFER_WRITES) != 0;
2201 STm->do_async_writes = (options & MT_ST_ASYNC_WRITES) != 0;
2202 STm->defaults_for_writes = (options & MT_ST_DEF_WRITES) != 0;
2203 STm->do_read_ahead = (options & MT_ST_READ_AHEAD) != 0;
2204 STp->two_fm = (options & MT_ST_TWO_FM) != 0;
2205 STp->fast_mteom = (options & MT_ST_FAST_MTEOM) != 0;
2206 STp->do_auto_lock = (options & MT_ST_AUTO_LOCK) != 0;
2207 STp->can_bsr = (options & MT_ST_CAN_BSR) != 0;
2208 STp->omit_blklims = (options & MT_ST_NO_BLKLIMS) != 0;
2209 if ((STp->device)->scsi_level >= SCSI_2)
2210 STp->can_partitions = (options & MT_ST_CAN_PARTITIONS) != 0;
2211 STp->scsi2_logical = (options & MT_ST_SCSI2LOGICAL) != 0;
2212 STp->immediate = (options & MT_ST_NOWAIT) != 0;
2213 STm->sysv = (options & MT_ST_SYSV) != 0;
2214 STp->sili = (options & MT_ST_SILI) != 0;
2215 DEB( debugging = (options & MT_ST_DEBUGGING) != 0;
2216 st_log_options(STp, STm, name); )
2217 } else if (code == MT_ST_SETBOOLEANS || code == MT_ST_CLEARBOOLEANS) {
2218 value = (code == MT_ST_SETBOOLEANS);
2219 if ((options & MT_ST_BUFFER_WRITES) != 0)
2220 STm->do_buffer_writes = value;
2221 if ((options & MT_ST_ASYNC_WRITES) != 0)
2222 STm->do_async_writes = value;
2223 if ((options & MT_ST_DEF_WRITES) != 0)
2224 STm->defaults_for_writes = value;
2225 if ((options & MT_ST_READ_AHEAD) != 0)
2226 STm->do_read_ahead = value;
2227 if ((options & MT_ST_TWO_FM) != 0)
2228 STp->two_fm = value;
2229 if ((options & MT_ST_FAST_MTEOM) != 0)
2230 STp->fast_mteom = value;
2231 if ((options & MT_ST_AUTO_LOCK) != 0)
2232 STp->do_auto_lock = value;
2233 if ((options & MT_ST_CAN_BSR) != 0)
2234 STp->can_bsr = value;
2235 if ((options & MT_ST_NO_BLKLIMS) != 0)
2236 STp->omit_blklims = value;
2237 if ((STp->device)->scsi_level >= SCSI_2 &&
2238 (options & MT_ST_CAN_PARTITIONS) != 0)
2239 STp->can_partitions = value;
2240 if ((options & MT_ST_SCSI2LOGICAL) != 0)
2241 STp->scsi2_logical = value;
2242 if ((options & MT_ST_NOWAIT) != 0)
2243 STp->immediate = value;
2244 if ((options & MT_ST_SYSV) != 0)
2245 STm->sysv = value;
2246 if ((options & MT_ST_SILI) != 0)
2247 STp->sili = value;
2248 DEB(
2249 if ((options & MT_ST_DEBUGGING) != 0)
2250 debugging = value;
2251 st_log_options(STp, STm, name); )
2252 } else if (code == MT_ST_WRITE_THRESHOLD) {
2253 /* Retained for compatibility */
2254 } else if (code == MT_ST_DEF_BLKSIZE) {
2255 value = (options & ~MT_ST_OPTIONS);
2256 if (value == ~MT_ST_OPTIONS) {
2257 STm->default_blksize = (-1);
2258 DEBC( printk(KERN_INFO "%s: Default block size disabled.\n", name));
2259 } else {
2260 STm->default_blksize = value;
2261 DEBC( printk(KERN_INFO "%s: Default block size set to %d bytes.\n",
2262 name, STm->default_blksize));
2263 if (STp->ready == ST_READY) {
2264 STp->blksize_changed = 0;
2265 set_mode_densblk(STp, STm);
2266 }
2267 }
2268 } else if (code == MT_ST_TIMEOUTS) {
2269 value = (options & ~MT_ST_OPTIONS);
2270 if ((value & MT_ST_SET_LONG_TIMEOUT) != 0) {
2271 STp->long_timeout = (value & ~MT_ST_SET_LONG_TIMEOUT) * HZ;
2272 DEBC( printk(KERN_INFO "%s: Long timeout set to %d seconds.\n", name,
2273 (value & ~MT_ST_SET_LONG_TIMEOUT)));
2274 } else {
2275 blk_queue_rq_timeout(STp->device->request_queue,
2276 value * HZ);
2277 DEBC( printk(KERN_INFO "%s: Normal timeout set to %d seconds.\n",
2278 name, value) );
2279 }
2280 } else if (code == MT_ST_SET_CLN) {
2281 value = (options & ~MT_ST_OPTIONS) & 0xff;
2282 if (value != 0 &&
2283 value < EXTENDED_SENSE_START && value >= SCSI_SENSE_BUFFERSIZE)
2284 return (-EINVAL);
2285 STp->cln_mode = value;
2286 STp->cln_sense_mask = (options >> 8) & 0xff;
2287 STp->cln_sense_value = (options >> 16) & 0xff;
2288 printk(KERN_INFO
2289 "%s: Cleaning request mode %d, mask %02x, value %02x\n",
2290 name, value, STp->cln_sense_mask, STp->cln_sense_value);
2291 } else if (code == MT_ST_DEF_OPTIONS) {
2292 code = (options & ~MT_ST_CLEAR_DEFAULT);
2293 value = (options & MT_ST_CLEAR_DEFAULT);
2294 if (code == MT_ST_DEF_DENSITY) {
2295 if (value == MT_ST_CLEAR_DEFAULT) {
2296 STm->default_density = (-1);
2297 DEBC( printk(KERN_INFO "%s: Density default disabled.\n",
2298 name));
2299 } else {
2300 STm->default_density = value & 0xff;
2301 DEBC( printk(KERN_INFO "%s: Density default set to %x\n",
2302 name, STm->default_density));
2303 if (STp->ready == ST_READY) {
2304 STp->density_changed = 0;
2305 set_mode_densblk(STp, STm);
2306 }
2307 }
2308 } else if (code == MT_ST_DEF_DRVBUFFER) {
2309 if (value == MT_ST_CLEAR_DEFAULT) {
2310 STp->default_drvbuffer = 0xff;
2311 DEBC( printk(KERN_INFO
2312 "%s: Drive buffer default disabled.\n", name));
2313 } else {
2314 STp->default_drvbuffer = value & 7;
2315 DEBC( printk(KERN_INFO
2316 "%s: Drive buffer default set to %x\n",
2317 name, STp->default_drvbuffer));
2318 if (STp->ready == ST_READY)
2319 st_int_ioctl(STp, MTSETDRVBUFFER, STp->default_drvbuffer);
2320 }
2321 } else if (code == MT_ST_DEF_COMPRESSION) {
2322 if (value == MT_ST_CLEAR_DEFAULT) {
2323 STm->default_compression = ST_DONT_TOUCH;
2324 DEBC( printk(KERN_INFO
2325 "%s: Compression default disabled.\n", name));
2326 } else {
2327 if ((value & 0xff00) != 0) {
2328 STp->c_algo = (value & 0xff00) >> 8;
2329 DEBC( printk(KERN_INFO "%s: Compression algorithm set to 0x%x.\n",
2330 name, STp->c_algo));
2331 }
2332 if ((value & 0xff) != 0xff) {
2333 STm->default_compression = (value & 1 ? ST_YES : ST_NO);
2334 DEBC( printk(KERN_INFO "%s: Compression default set to %x\n",
2335 name, (value & 1)));
2336 if (STp->ready == ST_READY) {
2337 STp->compression_changed = 0;
2338 st_compression(STp, (STm->default_compression == ST_YES));
2339 }
2340 }
2341 }
2342 }
2343 } else
2344 return (-EIO);
2345
2346 return 0;
2347 }
2348
2349 #define MODE_HEADER_LENGTH 4
2350
2351 /* Mode header and page byte offsets */
2352 #define MH_OFF_DATA_LENGTH 0
2353 #define MH_OFF_MEDIUM_TYPE 1
2354 #define MH_OFF_DEV_SPECIFIC 2
2355 #define MH_OFF_BDESCS_LENGTH 3
2356 #define MP_OFF_PAGE_NBR 0
2357 #define MP_OFF_PAGE_LENGTH 1
2358
2359 /* Mode header and page bit masks */
2360 #define MH_BIT_WP 0x80
2361 #define MP_MSK_PAGE_NBR 0x3f
2362
2363 /* Don't return block descriptors */
2364 #define MODE_SENSE_OMIT_BDESCS 0x08
2365
2366 #define MODE_SELECT_PAGE_FORMAT 0x10
2367
2368 /* Read a mode page into the tape buffer. The block descriptors are included
2369 if incl_block_descs is true. The page control is ored to the page number
2370 parameter, if necessary. */
2371 static int read_mode_page(struct scsi_tape *STp, int page, int omit_block_descs)
2372 {
2373 unsigned char cmd[MAX_COMMAND_SIZE];
2374 struct st_request *SRpnt;
2375
2376 memset(cmd, 0, MAX_COMMAND_SIZE);
2377 cmd[0] = MODE_SENSE;
2378 if (omit_block_descs)
2379 cmd[1] = MODE_SENSE_OMIT_BDESCS;
2380 cmd[2] = page;
2381 cmd[4] = 255;
2382
2383 SRpnt = st_do_scsi(NULL, STp, cmd, cmd[4], DMA_FROM_DEVICE,
2384 STp->device->request_queue->rq_timeout, 0, 1);
2385 if (SRpnt == NULL)
2386 return (STp->buffer)->syscall_result;
2387
2388 st_release_request(SRpnt);
2389
2390 return STp->buffer->syscall_result;
2391 }
2392
2393
2394 /* Send the mode page in the tape buffer to the drive. Assumes that the mode data
2395 in the buffer is correctly formatted. The long timeout is used if slow is non-zero. */
2396 static int write_mode_page(struct scsi_tape *STp, int page, int slow)
2397 {
2398 int pgo;
2399 unsigned char cmd[MAX_COMMAND_SIZE];
2400 struct st_request *SRpnt;
2401 int timeout;
2402
2403 memset(cmd, 0, MAX_COMMAND_SIZE);
2404 cmd[0] = MODE_SELECT;
2405 cmd[1] = MODE_SELECT_PAGE_FORMAT;
2406 pgo = MODE_HEADER_LENGTH + (STp->buffer)->b_data[MH_OFF_BDESCS_LENGTH];
2407 cmd[4] = pgo + (STp->buffer)->b_data[pgo + MP_OFF_PAGE_LENGTH] + 2;
2408
2409 /* Clear reserved fields */
2410 (STp->buffer)->b_data[MH_OFF_DATA_LENGTH] = 0;
2411 (STp->buffer)->b_data[MH_OFF_MEDIUM_TYPE] = 0;
2412 (STp->buffer)->b_data[MH_OFF_DEV_SPECIFIC] &= ~MH_BIT_WP;
2413 (STp->buffer)->b_data[pgo + MP_OFF_PAGE_NBR] &= MP_MSK_PAGE_NBR;
2414
2415 timeout = slow ?
2416 STp->long_timeout : STp->device->request_queue->rq_timeout;
2417 SRpnt = st_do_scsi(NULL, STp, cmd, cmd[4], DMA_TO_DEVICE,
2418 timeout, 0, 1);
2419 if (SRpnt == NULL)
2420 return (STp->buffer)->syscall_result;
2421
2422 st_release_request(SRpnt);
2423
2424 return STp->buffer->syscall_result;
2425 }
2426
2427
2428 #define COMPRESSION_PAGE 0x0f
2429 #define COMPRESSION_PAGE_LENGTH 16
2430
2431 #define CP_OFF_DCE_DCC 2
2432 #define CP_OFF_C_ALGO 7
2433
2434 #define DCE_MASK 0x80
2435 #define DCC_MASK 0x40
2436 #define RED_MASK 0x60
2437
2438
2439 /* Control the compression with mode page 15. Algorithm not changed if zero.
2440
2441 The block descriptors are read and written because Sony SDT-7000 does not
2442 work without this (suggestion from Michael Schaefer <Michael.Schaefer@dlr.de>).
2443 Including block descriptors should not cause any harm to other drives. */
2444
2445 static int st_compression(struct scsi_tape * STp, int state)
2446 {
2447 int retval;
2448 int mpoffs; /* Offset to mode page start */
2449 unsigned char *b_data = (STp->buffer)->b_data;
2450 DEB( char *name = tape_name(STp); )
2451
2452 if (STp->ready != ST_READY)
2453 return (-EIO);
2454
2455 /* Read the current page contents */
2456 retval = read_mode_page(STp, COMPRESSION_PAGE, 0);
2457 if (retval) {
2458 DEBC(printk(ST_DEB_MSG "%s: Compression mode page not supported.\n",
2459 name));
2460 return (-EIO);
2461 }
2462
2463 mpoffs = MODE_HEADER_LENGTH + b_data[MH_OFF_BDESCS_LENGTH];
2464 DEBC(printk(ST_DEB_MSG "%s: Compression state is %d.\n", name,
2465 (b_data[mpoffs + CP_OFF_DCE_DCC] & DCE_MASK ? 1 : 0)));
2466
2467 /* Check if compression can be changed */
2468 if ((b_data[mpoffs + CP_OFF_DCE_DCC] & DCC_MASK) == 0) {
2469 DEBC(printk(ST_DEB_MSG "%s: Compression not supported.\n", name));
2470 return (-EIO);
2471 }
2472
2473 /* Do the change */
2474 if (state) {
2475 b_data[mpoffs + CP_OFF_DCE_DCC] |= DCE_MASK;
2476 if (STp->c_algo != 0)
2477 b_data[mpoffs + CP_OFF_C_ALGO] = STp->c_algo;
2478 }
2479 else {
2480 b_data[mpoffs + CP_OFF_DCE_DCC] &= ~DCE_MASK;
2481 if (STp->c_algo != 0)
2482 b_data[mpoffs + CP_OFF_C_ALGO] = 0; /* no compression */
2483 }
2484
2485 retval = write_mode_page(STp, COMPRESSION_PAGE, 0);
2486 if (retval) {
2487 DEBC(printk(ST_DEB_MSG "%s: Compression change failed.\n", name));
2488 return (-EIO);
2489 }
2490 DEBC(printk(ST_DEB_MSG "%s: Compression state changed to %d.\n",
2491 name, state));
2492
2493 STp->compression_changed = 1;
2494 return 0;
2495 }
2496
2497
2498 /* Process the load and unload commands (does unload if the load code is zero) */
2499 static int do_load_unload(struct scsi_tape *STp, struct file *filp, int load_code)
2500 {
2501 int retval = (-EIO), timeout;
2502 DEB( char *name = tape_name(STp); )
2503 unsigned char cmd[MAX_COMMAND_SIZE];
2504 struct st_partstat *STps;
2505 struct st_request *SRpnt;
2506
2507 if (STp->ready != ST_READY && !load_code) {
2508 if (STp->ready == ST_NO_TAPE)
2509 return (-ENOMEDIUM);
2510 else
2511 return (-EIO);
2512 }
2513
2514 memset(cmd, 0, MAX_COMMAND_SIZE);
2515 cmd[0] = START_STOP;
2516 if (load_code)
2517 cmd[4] |= 1;
2518 /*
2519 * If arg >= 1 && arg <= 6 Enhanced load/unload in HP C1553A
2520 */
2521 if (load_code >= 1 + MT_ST_HPLOADER_OFFSET
2522 && load_code <= 6 + MT_ST_HPLOADER_OFFSET) {
2523 DEBC(printk(ST_DEB_MSG "%s: Enhanced %sload slot %2d.\n",
2524 name, (cmd[4]) ? "" : "un",
2525 load_code - MT_ST_HPLOADER_OFFSET));
2526 cmd[3] = load_code - MT_ST_HPLOADER_OFFSET; /* MediaID field of C1553A */
2527 }
2528 if (STp->immediate) {
2529 cmd[1] = 1; /* Don't wait for completion */
2530 timeout = STp->device->request_queue->rq_timeout;
2531 }
2532 else
2533 timeout = STp->long_timeout;
2534
2535 DEBC(
2536 if (!load_code)
2537 printk(ST_DEB_MSG "%s: Unloading tape.\n", name);
2538 else
2539 printk(ST_DEB_MSG "%s: Loading tape.\n", name);
2540 );
2541
2542 SRpnt = st_do_scsi(NULL, STp, cmd, 0, DMA_NONE,
2543 timeout, MAX_RETRIES, 1);
2544 if (!SRpnt)
2545 return (STp->buffer)->syscall_result;
2546
2547 retval = (STp->buffer)->syscall_result;
2548 st_release_request(SRpnt);
2549
2550 if (!retval) { /* SCSI command successful */
2551
2552 if (!load_code) {
2553 STp->rew_at_close = 0;
2554 STp->ready = ST_NO_TAPE;
2555 }
2556 else {
2557 STp->rew_at_close = STp->autorew_dev;
2558 retval = check_tape(STp, filp);
2559 if (retval > 0)
2560 retval = 0;
2561 }
2562 }
2563 else {
2564 STps = &(STp->ps[STp->partition]);
2565 STps->drv_file = STps->drv_block = (-1);
2566 }
2567
2568 return retval;
2569 }
2570
2571 #if DEBUG
2572 #define ST_DEB_FORWARD 0
2573 #define ST_DEB_BACKWARD 1
2574 static void deb_space_print(char *name, int direction, char *units, unsigned char *cmd)
2575 {
2576 s32 sc;
2577
2578 sc = cmd[2] & 0x80 ? 0xff000000 : 0;
2579 sc |= (cmd[2] << 16) | (cmd[3] << 8) | cmd[4];
2580 if (direction)
2581 sc = -sc;
2582 printk(ST_DEB_MSG "%s: Spacing tape %s over %d %s.\n", name,
2583 direction ? "backward" : "forward", sc, units);
2584 }
2585 #endif
2586
2587
2588 /* Internal ioctl function */
2589 static int st_int_ioctl(struct scsi_tape *STp, unsigned int cmd_in, unsigned long arg)
2590 {
2591 int timeout;
2592 long ltmp;
2593 int ioctl_result;
2594 int chg_eof = 1;
2595 unsigned char cmd[MAX_COMMAND_SIZE];
2596 struct st_request *SRpnt;
2597 struct st_partstat *STps;
2598 int fileno, blkno, at_sm, undone;
2599 int datalen = 0, direction = DMA_NONE;
2600 char *name = tape_name(STp);
2601
2602 WARN_ON(STp->buffer->do_dio != 0);
2603 if (STp->ready != ST_READY) {
2604 if (STp->ready == ST_NO_TAPE)
2605 return (-ENOMEDIUM);
2606 else
2607 return (-EIO);
2608 }
2609 timeout = STp->long_timeout;
2610 STps = &(STp->ps[STp->partition]);
2611 fileno = STps->drv_file;
2612 blkno = STps->drv_block;
2613 at_sm = STps->at_sm;
2614
2615 memset(cmd, 0, MAX_COMMAND_SIZE);
2616 switch (cmd_in) {
2617 case MTFSFM:
2618 chg_eof = 0; /* Changed from the FSF after this */
2619 case MTFSF:
2620 cmd[0] = SPACE;
2621 cmd[1] = 0x01; /* Space FileMarks */
2622 cmd[2] = (arg >> 16);
2623 cmd[3] = (arg >> 8);
2624 cmd[4] = arg;
2625 DEBC(deb_space_print(name, ST_DEB_FORWARD, "filemarks", cmd);)
2626 if (fileno >= 0)
2627 fileno += arg;
2628 blkno = 0;
2629 at_sm &= (arg == 0);
2630 break;
2631 case MTBSFM:
2632 chg_eof = 0; /* Changed from the FSF after this */
2633 case MTBSF:
2634 cmd[0] = SPACE;
2635 cmd[1] = 0x01; /* Space FileMarks */
2636 ltmp = (-arg);
2637 cmd[2] = (ltmp >> 16);
2638 cmd[3] = (ltmp >> 8);
2639 cmd[4] = ltmp;
2640 DEBC(deb_space_print(name, ST_DEB_BACKWARD, "filemarks", cmd);)
2641 if (fileno >= 0)
2642 fileno -= arg;
2643 blkno = (-1); /* We can't know the block number */
2644 at_sm &= (arg == 0);
2645 break;
2646 case MTFSR:
2647 cmd[0] = SPACE;
2648 cmd[1] = 0x00; /* Space Blocks */
2649 cmd[2] = (arg >> 16);
2650 cmd[3] = (arg >> 8);
2651 cmd[4] = arg;
2652 DEBC(deb_space_print(name, ST_DEB_FORWARD, "blocks", cmd);)
2653 if (blkno >= 0)
2654 blkno += arg;
2655 at_sm &= (arg == 0);
2656 break;
2657 case MTBSR:
2658 cmd[0] = SPACE;
2659 cmd[1] = 0x00; /* Space Blocks */
2660 ltmp = (-arg);
2661 cmd[2] = (ltmp >> 16);
2662 cmd[3] = (ltmp >> 8);
2663 cmd[4] = ltmp;
2664 DEBC(deb_space_print(name, ST_DEB_BACKWARD, "blocks", cmd);)
2665 if (blkno >= 0)
2666 blkno -= arg;
2667 at_sm &= (arg == 0);
2668 break;
2669 case MTFSS:
2670 cmd[0] = SPACE;
2671 cmd[1] = 0x04; /* Space Setmarks */
2672 cmd[2] = (arg >> 16);
2673 cmd[3] = (arg >> 8);
2674 cmd[4] = arg;
2675 DEBC(deb_space_print(name, ST_DEB_FORWARD, "setmarks", cmd);)
2676 if (arg != 0) {
2677 blkno = fileno = (-1);
2678 at_sm = 1;
2679 }
2680 break;
2681 case MTBSS:
2682 cmd[0] = SPACE;
2683 cmd[1] = 0x04; /* Space Setmarks */
2684 ltmp = (-arg);
2685 cmd[2] = (ltmp >> 16);
2686 cmd[3] = (ltmp >> 8);
2687 cmd[4] = ltmp;
2688 DEBC(deb_space_print(name, ST_DEB_BACKWARD, "setmarks", cmd);)
2689 if (arg != 0) {
2690 blkno = fileno = (-1);
2691 at_sm = 1;
2692 }
2693 break;
2694 case MTWEOF:
2695 case MTWSM:
2696 if (STp->write_prot)
2697 return (-EACCES);
2698 cmd[0] = WRITE_FILEMARKS;
2699 if (cmd_in == MTWSM)
2700 cmd[1] = 2;
2701 cmd[2] = (arg >> 16);
2702 cmd[3] = (arg >> 8);
2703 cmd[4] = arg;
2704 timeout = STp->device->request_queue->rq_timeout;
2705 DEBC(
2706 if (cmd_in == MTWEOF)
2707 printk(ST_DEB_MSG "%s: Writing %d filemarks.\n", name,
2708 cmd[2] * 65536 + cmd[3] * 256 + cmd[4]);
2709 else
2710 printk(ST_DEB_MSG "%s: Writing %d setmarks.\n", name,
2711 cmd[2] * 65536 + cmd[3] * 256 + cmd[4]);
2712 )
2713 if (fileno >= 0)
2714 fileno += arg;
2715 blkno = 0;
2716 at_sm = (cmd_in == MTWSM);
2717 break;
2718 case MTREW:
2719 cmd[0] = REZERO_UNIT;
2720 if (STp->immediate) {
2721 cmd[1] = 1; /* Don't wait for completion */
2722 timeout = STp->device->request_queue->rq_timeout;
2723 }
2724 DEBC(printk(ST_DEB_MSG "%s: Rewinding tape.\n", name));
2725 fileno = blkno = at_sm = 0;
2726 break;
2727 case MTNOP:
2728 DEBC(printk(ST_DEB_MSG "%s: No op on tape.\n", name));
2729 return 0; /* Should do something ? */
2730 break;
2731 case MTRETEN:
2732 cmd[0] = START_STOP;
2733 if (STp->immediate) {
2734 cmd[1] = 1; /* Don't wait for completion */
2735 timeout = STp->device->request_queue->rq_timeout;
2736 }
2737 cmd[4] = 3;
2738 DEBC(printk(ST_DEB_MSG "%s: Retensioning tape.\n", name));
2739 fileno = blkno = at_sm = 0;
2740 break;
2741 case MTEOM:
2742 if (!STp->fast_mteom) {
2743 /* space to the end of tape */
2744 ioctl_result = st_int_ioctl(STp, MTFSF, 0x7fffff);
2745 fileno = STps->drv_file;
2746 if (STps->eof >= ST_EOD_1)
2747 return 0;
2748 /* The next lines would hide the number of spaced FileMarks
2749 That's why I inserted the previous lines. I had no luck
2750 with detecting EOM with FSF, so we go now to EOM.
2751 Joerg Weule */
2752 } else
2753 fileno = (-1);
2754 cmd[0] = SPACE;
2755 cmd[1] = 3;
2756 DEBC(printk(ST_DEB_MSG "%s: Spacing to end of recorded medium.\n",
2757 name));
2758 blkno = -1;
2759 at_sm = 0;
2760 break;
2761 case MTERASE:
2762 if (STp->write_prot)
2763 return (-EACCES);
2764 cmd[0] = ERASE;
2765 cmd[1] = (arg ? 1 : 0); /* Long erase with non-zero argument */
2766 if (STp->immediate) {
2767 cmd[1] |= 2; /* Don't wait for completion */
2768 timeout = STp->device->request_queue->rq_timeout;
2769 }
2770 else
2771 timeout = STp->long_timeout * 8;
2772
2773 DEBC(printk(ST_DEB_MSG "%s: Erasing tape.\n", name));
2774 fileno = blkno = at_sm = 0;
2775 break;
2776 case MTSETBLK: /* Set block length */
2777 case MTSETDENSITY: /* Set tape density */
2778 case MTSETDRVBUFFER: /* Set drive buffering */
2779 case SET_DENS_AND_BLK: /* Set density and block size */
2780 chg_eof = 0;
2781 if (STp->dirty || (STp->buffer)->buffer_bytes != 0)
2782 return (-EIO); /* Not allowed if data in buffer */
2783 if ((cmd_in == MTSETBLK || cmd_in == SET_DENS_AND_BLK) &&
2784 (arg & MT_ST_BLKSIZE_MASK) != 0 &&
2785 STp->max_block > 0 &&
2786 ((arg & MT_ST_BLKSIZE_MASK) < STp->min_block ||
2787 (arg & MT_ST_BLKSIZE_MASK) > STp->max_block)) {
2788 printk(KERN_WARNING "%s: Illegal block size.\n", name);
2789 return (-EINVAL);
2790 }
2791 cmd[0] = MODE_SELECT;
2792 if ((STp->use_pf & USE_PF))
2793 cmd[1] = MODE_SELECT_PAGE_FORMAT;
2794 cmd[4] = datalen = 12;
2795 direction = DMA_TO_DEVICE;
2796
2797 memset((STp->buffer)->b_data, 0, 12);
2798 if (cmd_in == MTSETDRVBUFFER)
2799 (STp->buffer)->b_data[2] = (arg & 7) << 4;
2800 else
2801 (STp->buffer)->b_data[2] =
2802 STp->drv_buffer << 4;
2803 (STp->buffer)->b_data[3] = 8; /* block descriptor length */
2804 if (cmd_in == MTSETDENSITY) {
2805 (STp->buffer)->b_data[4] = arg;
2806 STp->density_changed = 1; /* At least we tried ;-) */
2807 } else if (cmd_in == SET_DENS_AND_BLK)
2808 (STp->buffer)->b_data[4] = arg >> 24;
2809 else
2810 (STp->buffer)->b_data[4] = STp->density;
2811 if (cmd_in == MTSETBLK || cmd_in == SET_DENS_AND_BLK) {
2812 ltmp = arg & MT_ST_BLKSIZE_MASK;
2813 if (cmd_in == MTSETBLK)
2814 STp->blksize_changed = 1; /* At least we tried ;-) */
2815 } else
2816 ltmp = STp->block_size;
2817 (STp->buffer)->b_data[9] = (ltmp >> 16);
2818 (STp->buffer)->b_data[10] = (ltmp >> 8);
2819 (STp->buffer)->b_data[11] = ltmp;
2820 timeout = STp->device->request_queue->rq_timeout;
2821 DEBC(
2822 if (cmd_in == MTSETBLK || cmd_in == SET_DENS_AND_BLK)
2823 printk(ST_DEB_MSG
2824 "%s: Setting block size to %d bytes.\n", name,
2825 (STp->buffer)->b_data[9] * 65536 +
2826 (STp->buffer)->b_data[10] * 256 +
2827 (STp->buffer)->b_data[11]);
2828 if (cmd_in == MTSETDENSITY || cmd_in == SET_DENS_AND_BLK)
2829 printk(ST_DEB_MSG
2830 "%s: Setting density code to %x.\n", name,
2831 (STp->buffer)->b_data[4]);
2832 if (cmd_in == MTSETDRVBUFFER)
2833 printk(ST_DEB_MSG
2834 "%s: Setting drive buffer code to %d.\n", name,
2835 ((STp->buffer)->b_data[2] >> 4) & 7);
2836 )
2837 break;
2838 default:
2839 return (-ENOSYS);
2840 }
2841
2842 SRpnt = st_do_scsi(NULL, STp, cmd, datalen, direction,
2843 timeout, MAX_RETRIES, 1);
2844 if (!SRpnt)
2845 return (STp->buffer)->syscall_result;
2846
2847 ioctl_result = (STp->buffer)->syscall_result;
2848
2849 if (!ioctl_result) { /* SCSI command successful */
2850 st_release_request(SRpnt);
2851 SRpnt = NULL;
2852 STps->drv_block = blkno;
2853 STps->drv_file = fileno;
2854 STps->at_sm = at_sm;
2855
2856 if (cmd_in == MTBSFM)
2857 ioctl_result = st_int_ioctl(STp, MTFSF, 1);
2858 else if (cmd_in == MTFSFM)
2859 ioctl_result = st_int_ioctl(STp, MTBSF, 1);
2860
2861 if (cmd_in == MTSETBLK || cmd_in == SET_DENS_AND_BLK) {
2862 int old_block_size = STp->block_size;
2863 STp->block_size = arg & MT_ST_BLKSIZE_MASK;
2864 if (STp->block_size != 0) {
2865 if (old_block_size == 0)
2866 normalize_buffer(STp->buffer);
2867 (STp->buffer)->buffer_blocks =
2868 (STp->buffer)->buffer_size / STp->block_size;
2869 }
2870 (STp->buffer)->buffer_bytes = (STp->buffer)->read_pointer = 0;
2871 if (cmd_in == SET_DENS_AND_BLK)
2872 STp->density = arg >> MT_ST_DENSITY_SHIFT;
2873 } else if (cmd_in == MTSETDRVBUFFER)
2874 STp->drv_buffer = (arg & 7);
2875 else if (cmd_in == MTSETDENSITY)
2876 STp->density = arg;
2877
2878 if (cmd_in == MTEOM)
2879 STps->eof = ST_EOD;
2880 else if (cmd_in == MTFSF)
2881 STps->eof = ST_FM;
2882 else if (chg_eof)
2883 STps->eof = ST_NOEOF;
2884
2885 if (cmd_in == MTWEOF)
2886 STps->rw = ST_IDLE;
2887 } else { /* SCSI command was not completely successful. Don't return
2888 from this block without releasing the SCSI command block! */
2889 struct st_cmdstatus *cmdstatp = &STp->buffer->cmdstat;
2890
2891 if (cmdstatp->flags & SENSE_EOM) {
2892 if (cmd_in != MTBSF && cmd_in != MTBSFM &&
2893 cmd_in != MTBSR && cmd_in != MTBSS)
2894 STps->eof = ST_EOM_OK;
2895 STps->drv_block = 0;
2896 }
2897
2898 if (cmdstatp->remainder_valid)
2899 undone = (int)cmdstatp->uremainder64;
2900 else
2901 undone = 0;
2902
2903 if (cmd_in == MTWEOF &&
2904 cmdstatp->have_sense &&
2905 (cmdstatp->flags & SENSE_EOM)) {
2906 if (cmdstatp->sense_hdr.sense_key == NO_SENSE ||
2907 cmdstatp->sense_hdr.sense_key == RECOVERED_ERROR) {
2908 ioctl_result = 0; /* EOF(s) written successfully at EOM */
2909 STps->eof = ST_NOEOF;
2910 } else { /* Writing EOF(s) failed */
2911 if (fileno >= 0)
2912 fileno -= undone;
2913 if (undone < arg)
2914 STps->eof = ST_NOEOF;
2915 }
2916 STps->drv_file = fileno;
2917 } else if ((cmd_in == MTFSF) || (cmd_in == MTFSFM)) {
2918 if (fileno >= 0)
2919 STps->drv_file = fileno - undone;
2920 else
2921 STps->drv_file = fileno;
2922 STps->drv_block = -1;
2923 STps->eof = ST_NOEOF;
2924 } else if ((cmd_in == MTBSF) || (cmd_in == MTBSFM)) {
2925 if (arg > 0 && undone < 0) /* Some drives get this wrong */
2926 undone = (-undone);
2927 if (STps->drv_file >= 0)
2928 STps->drv_file = fileno + undone;
2929 STps->drv_block = 0;
2930 STps->eof = ST_NOEOF;
2931 } else if (cmd_in == MTFSR) {
2932 if (cmdstatp->flags & SENSE_FMK) { /* Hit filemark */
2933 if (STps->drv_file >= 0)
2934 STps->drv_file++;
2935 STps->drv_block = 0;
2936 STps->eof = ST_FM;
2937 } else {
2938 if (blkno >= undone)
2939 STps->drv_block = blkno - undone;
2940 else
2941 STps->drv_block = (-1);
2942 STps->eof = ST_NOEOF;
2943 }
2944 } else if (cmd_in == MTBSR) {
2945 if (cmdstatp->flags & SENSE_FMK) { /* Hit filemark */
2946 STps->drv_file--;
2947 STps->drv_block = (-1);
2948 } else {
2949 if (arg > 0 && undone < 0) /* Some drives get this wrong */
2950 undone = (-undone);
2951 if (STps->drv_block >= 0)
2952 STps->drv_block = blkno + undone;
2953 }
2954 STps->eof = ST_NOEOF;
2955 } else if (cmd_in == MTEOM) {
2956 STps->drv_file = (-1);
2957 STps->drv_block = (-1);
2958 STps->eof = ST_EOD;
2959 } else if (cmd_in == MTSETBLK ||
2960 cmd_in == MTSETDENSITY ||
2961 cmd_in == MTSETDRVBUFFER ||
2962 cmd_in == SET_DENS_AND_BLK) {
2963 if (cmdstatp->sense_hdr.sense_key == ILLEGAL_REQUEST &&
2964 !(STp->use_pf & PF_TESTED)) {
2965 /* Try the other possible state of Page Format if not
2966 already tried */
2967 STp->use_pf = (STp->use_pf ^ USE_PF) | PF_TESTED;
2968 st_release_request(SRpnt);
2969 SRpnt = NULL;
2970 return st_int_ioctl(STp, cmd_in, arg);
2971 }
2972 } else if (chg_eof)
2973 STps->eof = ST_NOEOF;
2974
2975 if (cmdstatp->sense_hdr.sense_key == BLANK_CHECK)
2976 STps->eof = ST_EOD;
2977
2978 st_release_request(SRpnt);
2979 SRpnt = NULL;
2980 }
2981
2982 return ioctl_result;
2983 }
2984
2985
2986 /* Get the tape position. If bt == 2, arg points into a kernel space mt_loc
2987 structure. */
2988
2989 static int get_location(struct scsi_tape *STp, unsigned int *block, int *partition,
2990 int logical)
2991 {
2992 int result;
2993 unsigned char scmd[MAX_COMMAND_SIZE];
2994 struct st_request *SRpnt;
2995 DEB( char *name = tape_name(STp); )
2996
2997 if (STp->ready != ST_READY)
2998 return (-EIO);
2999
3000 memset(scmd, 0, MAX_COMMAND_SIZE);
3001 if ((STp->device)->scsi_level < SCSI_2) {
3002 scmd[0] = QFA_REQUEST_BLOCK;
3003 scmd[4] = 3;
3004 } else {
3005 scmd[0] = READ_POSITION;
3006 if (!logical && !STp->scsi2_logical)
3007 scmd[1] = 1;
3008 }
3009 SRpnt = st_do_scsi(NULL, STp, scmd, 20, DMA_FROM_DEVICE,
3010 STp->device->request_queue->rq_timeout,
3011 MAX_READY_RETRIES, 1);
3012 if (!SRpnt)
3013 return (STp->buffer)->syscall_result;
3014
3015 if ((STp->buffer)->syscall_result != 0 ||
3016 (STp->device->scsi_level >= SCSI_2 &&
3017 ((STp->buffer)->b_data[0] & 4) != 0)) {
3018 *block = *partition = 0;
3019 DEBC(printk(ST_DEB_MSG "%s: Can't read tape position.\n", name));
3020 result = (-EIO);
3021 } else {
3022 result = 0;
3023 if ((STp->device)->scsi_level < SCSI_2) {
3024 *block = ((STp->buffer)->b_data[0] << 16)
3025 + ((STp->buffer)->b_data[1] << 8)
3026 + (STp->buffer)->b_data[2];
3027 *partition = 0;
3028 } else {
3029 *block = ((STp->buffer)->b_data[4] << 24)
3030 + ((STp->buffer)->b_data[5] << 16)
3031 + ((STp->buffer)->b_data[6] << 8)
3032 + (STp->buffer)->b_data[7];
3033 *partition = (STp->buffer)->b_data[1];
3034 if (((STp->buffer)->b_data[0] & 0x80) &&
3035 (STp->buffer)->b_data[1] == 0) /* BOP of partition 0 */
3036 STp->ps[0].drv_block = STp->ps[0].drv_file = 0;
3037 }
3038 DEBC(printk(ST_DEB_MSG "%s: Got tape pos. blk %d part %d.\n", name,
3039 *block, *partition));
3040 }
3041 st_release_request(SRpnt);
3042 SRpnt = NULL;
3043
3044 return result;
3045 }
3046
3047
3048 /* Set the tape block and partition. Negative partition means that only the
3049 block should be set in vendor specific way. */
3050 static int set_location(struct scsi_tape *STp, unsigned int block, int partition,
3051 int logical)
3052 {
3053 struct st_partstat *STps;
3054 int result, p;
3055 unsigned int blk;
3056 int timeout;
3057 unsigned char scmd[MAX_COMMAND_SIZE];
3058 struct st_request *SRpnt;
3059 DEB( char *name = tape_name(STp); )
3060
3061 if (STp->ready != ST_READY)
3062 return (-EIO);
3063 timeout = STp->long_timeout;
3064 STps = &(STp->ps[STp->partition]);
3065
3066 DEBC(printk(ST_DEB_MSG "%s: Setting block to %d and partition to %d.\n",
3067 name, block, partition));
3068 DEB(if (partition < 0)
3069 return (-EIO); )
3070
3071 /* Update the location at the partition we are leaving */
3072 if ((!STp->can_partitions && partition != 0) ||
3073 partition >= ST_NBR_PARTITIONS)
3074 return (-EINVAL);
3075 if (partition != STp->partition) {
3076 if (get_location(STp, &blk, &p, 1))
3077 STps->last_block_valid = 0;
3078 else {
3079 STps->last_block_valid = 1;
3080 STps->last_block_visited = blk;
3081 DEBC(printk(ST_DEB_MSG
3082 "%s: Visited block %d for partition %d saved.\n",
3083 name, blk, STp->partition));
3084 }
3085 }
3086
3087 memset(scmd, 0, MAX_COMMAND_SIZE);
3088 if ((STp->device)->scsi_level < SCSI_2) {
3089 scmd[0] = QFA_SEEK_BLOCK;
3090 scmd[2] = (block >> 16);
3091 scmd[3] = (block >> 8);
3092 scmd[4] = block;
3093 scmd[5] = 0;
3094 } else {
3095 scmd[0] = SEEK_10;
3096 scmd[3] = (block >> 24);
3097 scmd[4] = (block >> 16);
3098 scmd[5] = (block >> 8);
3099 scmd[6] = block;
3100 if (!logical && !STp->scsi2_logical)
3101 scmd[1] = 4;
3102 if (STp->partition != partition) {
3103 scmd[1] |= 2;
3104 scmd[8] = partition;
3105 DEBC(printk(ST_DEB_MSG
3106 "%s: Trying to change partition from %d to %d\n",
3107 name, STp->partition, partition));
3108 }
3109 }
3110 if (STp->immediate) {
3111 scmd[1] |= 1; /* Don't wait for completion */
3112 timeout = STp->device->request_queue->rq_timeout;
3113 }
3114
3115 SRpnt = st_do_scsi(NULL, STp, scmd, 0, DMA_NONE,
3116 timeout, MAX_READY_RETRIES, 1);
3117 if (!SRpnt)
3118 return (STp->buffer)->syscall_result;
3119
3120 STps->drv_block = STps->drv_file = (-1);
3121 STps->eof = ST_NOEOF;
3122 if ((STp->buffer)->syscall_result != 0) {
3123 result = (-EIO);
3124 if (STp->can_partitions &&
3125 (STp->device)->scsi_level >= SCSI_2 &&
3126 (p = find_partition(STp)) >= 0)
3127 STp->partition = p;
3128 } else {
3129 if (STp->can_partitions) {
3130 STp->partition = partition;
3131 STps = &(STp->ps[partition]);
3132 if (!STps->last_block_valid ||
3133 STps->last_block_visited != block) {
3134 STps->at_sm = 0;
3135 STps->rw = ST_IDLE;
3136 }
3137 } else
3138 STps->at_sm = 0;
3139 if (block == 0)
3140 STps->drv_block = STps->drv_file = 0;
3141 result = 0;
3142 }
3143
3144 st_release_request(SRpnt);
3145 SRpnt = NULL;
3146
3147 return result;
3148 }
3149
3150
3151 /* Find the current partition number for the drive status. Called from open and
3152 returns either partition number of negative error code. */
3153 static int find_partition(struct scsi_tape *STp)
3154 {
3155 int i, partition;
3156 unsigned int block;
3157
3158 if ((i = get_location(STp, &block, &partition, 1)) < 0)
3159 return i;
3160 if (partition >= ST_NBR_PARTITIONS)
3161 return (-EIO);
3162 return partition;
3163 }
3164
3165
3166 /* Change the partition if necessary */
3167 static int switch_partition(struct scsi_tape *STp)
3168 {
3169 struct st_partstat *STps;
3170
3171 if (STp->partition == STp->new_partition)
3172 return 0;
3173 STps = &(STp->ps[STp->new_partition]);
3174 if (!STps->last_block_valid)
3175 STps->last_block_visited = 0;
3176 return set_location(STp, STps->last_block_visited, STp->new_partition, 1);
3177 }
3178
3179 /* Functions for reading and writing the medium partition mode page. */
3180
3181 #define PART_PAGE 0x11
3182 #define PART_PAGE_FIXED_LENGTH 8
3183
3184 #define PP_OFF_MAX_ADD_PARTS 2
3185 #define PP_OFF_NBR_ADD_PARTS 3
3186 #define PP_OFF_FLAGS 4
3187 #define PP_OFF_PART_UNITS 6
3188 #define PP_OFF_RESERVED 7
3189
3190 #define PP_BIT_IDP 0x20
3191 #define PP_MSK_PSUM_MB 0x10
3192
3193 /* Get the number of partitions on the tape. As a side effect reads the
3194 mode page into the tape buffer. */
3195 static int nbr_partitions(struct scsi_tape *STp)
3196 {
3197 int result;
3198 DEB( char *name = tape_name(STp); )
3199
3200 if (STp->ready != ST_READY)
3201 return (-EIO);
3202
3203 result = read_mode_page(STp, PART_PAGE, 1);
3204
3205 if (result) {
3206 DEBC(printk(ST_DEB_MSG "%s: Can't read medium partition page.\n",
3207 name));
3208 result = (-EIO);
3209 } else {
3210 result = (STp->buffer)->b_data[MODE_HEADER_LENGTH +
3211 PP_OFF_NBR_ADD_PARTS] + 1;
3212 DEBC(printk(ST_DEB_MSG "%s: Number of partitions %d.\n", name, result));
3213 }
3214
3215 return result;
3216 }
3217
3218
3219 /* Partition the tape into two partitions if size > 0 or one partition if
3220 size == 0.
3221
3222 The block descriptors are read and written because Sony SDT-7000 does not
3223 work without this (suggestion from Michael Schaefer <Michael.Schaefer@dlr.de>).
3224
3225 My HP C1533A drive returns only one partition size field. This is used to
3226 set the size of partition 1. There is no size field for the default partition.
3227 Michael Schaefer's Sony SDT-7000 returns two descriptors and the second is
3228 used to set the size of partition 1 (this is what the SCSI-3 standard specifies).
3229 The following algorithm is used to accommodate both drives: if the number of
3230 partition size fields is greater than the maximum number of additional partitions
3231 in the mode page, the second field is used. Otherwise the first field is used.
3232
3233 For Seagate DDS drives the page length must be 8 when no partitions is defined
3234 and 10 when 1 partition is defined (information from Eric Lee Green). This is
3235 is acceptable also to some other old drives and enforced if the first partition
3236 size field is used for the first additional partition size.
3237 */
3238 static int partition_tape(struct scsi_tape *STp, int size)
3239 {
3240 char *name = tape_name(STp);
3241 int result;
3242 int pgo, psd_cnt, psdo;
3243 unsigned char *bp;
3244
3245 result = read_mode_page(STp, PART_PAGE, 0);
3246 if (result) {
3247 DEBC(printk(ST_DEB_MSG "%s: Can't read partition mode page.\n", name));
3248 return result;
3249 }
3250 /* The mode page is in the buffer. Let's modify it and write it. */
3251 bp = (STp->buffer)->b_data;
3252 pgo = MODE_HEADER_LENGTH + bp[MH_OFF_BDESCS_LENGTH];
3253 DEBC(printk(ST_DEB_MSG "%s: Partition page length is %d bytes.\n",
3254 name, bp[pgo + MP_OFF_PAGE_LENGTH] + 2));
3255
3256 psd_cnt = (bp[pgo + MP_OFF_PAGE_LENGTH] + 2 - PART_PAGE_FIXED_LENGTH) / 2;
3257 psdo = pgo + PART_PAGE_FIXED_LENGTH;
3258 if (psd_cnt > bp[pgo + PP_OFF_MAX_ADD_PARTS]) {
3259 bp[psdo] = bp[psdo + 1] = 0xff; /* Rest of the tape */
3260 psdo += 2;
3261 }
3262 memset(bp + psdo, 0, bp[pgo + PP_OFF_NBR_ADD_PARTS] * 2);
3263
3264 DEBC(printk("%s: psd_cnt %d, max.parts %d, nbr_parts %d\n", name,
3265 psd_cnt, bp[pgo + PP_OFF_MAX_ADD_PARTS],
3266 bp[pgo + PP_OFF_NBR_ADD_PARTS]));
3267
3268 if (size <= 0) {
3269 bp[pgo + PP_OFF_NBR_ADD_PARTS] = 0;
3270 if (psd_cnt <= bp[pgo + PP_OFF_MAX_ADD_PARTS])
3271 bp[pgo + MP_OFF_PAGE_LENGTH] = 6;
3272 DEBC(printk(ST_DEB_MSG "%s: Formatting tape with one partition.\n",
3273 name));
3274 } else {
3275 bp[psdo] = (size >> 8) & 0xff;
3276 bp[psdo + 1] = size & 0xff;
3277 bp[pgo + 3] = 1;
3278 if (bp[pgo + MP_OFF_PAGE_LENGTH] < 8)
3279 bp[pgo + MP_OFF_PAGE_LENGTH] = 8;
3280 DEBC(printk(ST_DEB_MSG
3281 "%s: Formatting tape with two partitions (1 = %d MB).\n",
3282 name, size));
3283 }
3284 bp[pgo + PP_OFF_PART_UNITS] = 0;
3285 bp[pgo + PP_OFF_RESERVED] = 0;
3286 bp[pgo + PP_OFF_FLAGS] = PP_BIT_IDP | PP_MSK_PSUM_MB;
3287
3288 result = write_mode_page(STp, PART_PAGE, 1);
3289 if (result) {
3290 printk(KERN_INFO "%s: Partitioning of tape failed.\n", name);
3291 result = (-EIO);
3292 }
3293
3294 return result;
3295 }
3296
3297
3298
3299 /* The ioctl command */
3300 static long st_ioctl(struct file *file, unsigned int cmd_in, unsigned long arg)
3301 {
3302 int i, cmd_nr, cmd_type, bt;
3303 int retval = 0;
3304 unsigned int blk;
3305 struct scsi_tape *STp = file->private_data;
3306 struct st_modedef *STm;
3307 struct st_partstat *STps;
3308 char *name = tape_name(STp);
3309 void __user *p = (void __user *)arg;
3310
3311 if (mutex_lock_interruptible(&STp->lock))
3312 return -ERESTARTSYS;
3313
3314 DEB(
3315 if (debugging && !STp->in_use) {
3316 printk(ST_DEB_MSG "%s: Incorrect device.\n", name);
3317 retval = (-EIO);
3318 goto out;
3319 } ) /* end DEB */
3320
3321 STm = &(STp->modes[STp->current_mode]);
3322 STps = &(STp->ps[STp->partition]);
3323
3324 /*
3325 * If we are in the middle of error recovery, don't let anyone
3326 * else try and use this device. Also, if error recovery fails, it
3327 * may try and take the device offline, in which case all further
3328 * access to the device is prohibited.
3329 */
3330 retval = scsi_nonblockable_ioctl(STp->device, cmd_in, p,
3331 file->f_flags & O_NDELAY);
3332 if (!scsi_block_when_processing_errors(STp->device) || retval != -ENODEV)
3333 goto out;
3334 retval = 0;
3335
3336 cmd_type = _IOC_TYPE(cmd_in);
3337 cmd_nr = _IOC_NR(cmd_in);
3338
3339 if (cmd_type == _IOC_TYPE(MTIOCTOP) && cmd_nr == _IOC_NR(MTIOCTOP)) {
3340 struct mtop mtc;
3341
3342 if (_IOC_SIZE(cmd_in) != sizeof(mtc)) {
3343 retval = (-EINVAL);
3344 goto out;
3345 }
3346
3347 i = copy_from_user(&mtc, p, sizeof(struct mtop));
3348 if (i) {
3349 retval = (-EFAULT);
3350 goto out;
3351 }
3352
3353 if (mtc.mt_op == MTSETDRVBUFFER && !capable(CAP_SYS_ADMIN)) {
3354 printk(KERN_WARNING
3355 "%s: MTSETDRVBUFFER only allowed for root.\n", name);
3356 retval = (-EPERM);
3357 goto out;
3358 }
3359 if (!STm->defined &&
3360 (mtc.mt_op != MTSETDRVBUFFER &&
3361 (mtc.mt_count & MT_ST_OPTIONS) == 0)) {
3362 retval = (-ENXIO);
3363 goto out;
3364 }
3365
3366 if (!STp->pos_unknown) {
3367
3368 if (STps->eof == ST_FM_HIT) {
3369 if (mtc.mt_op == MTFSF || mtc.mt_op == MTFSFM ||
3370 mtc.mt_op == MTEOM) {
3371 mtc.mt_count -= 1;
3372 if (STps->drv_file >= 0)
3373 STps->drv_file += 1;
3374 } else if (mtc.mt_op == MTBSF || mtc.mt_op == MTBSFM) {
3375 mtc.mt_count += 1;
3376 if (STps->drv_file >= 0)
3377 STps->drv_file += 1;
3378 }
3379 }
3380
3381 if (mtc.mt_op == MTSEEK) {
3382 /* Old position must be restored if partition will be
3383 changed */
3384 i = !STp->can_partitions ||
3385 (STp->new_partition != STp->partition);
3386 } else {
3387 i = mtc.mt_op == MTREW || mtc.mt_op == MTOFFL ||
3388 mtc.mt_op == MTRETEN || mtc.mt_op == MTEOM ||
3389 mtc.mt_op == MTLOCK || mtc.mt_op == MTLOAD ||
3390 mtc.mt_op == MTFSF || mtc.mt_op == MTFSFM ||
3391 mtc.mt_op == MTBSF || mtc.mt_op == MTBSFM ||
3392 mtc.mt_op == MTCOMPRESSION;
3393 }
3394 i = flush_buffer(STp, i);
3395 if (i < 0) {
3396 retval = i;
3397 goto out;
3398 }
3399 if (STps->rw == ST_WRITING &&
3400 (mtc.mt_op == MTREW || mtc.mt_op == MTOFFL ||
3401 mtc.mt_op == MTSEEK ||
3402 mtc.mt_op == MTBSF || mtc.mt_op == MTBSFM)) {
3403 i = st_int_ioctl(STp, MTWEOF, 1);
3404 if (i < 0) {
3405 retval = i;
3406 goto out;
3407 }
3408 if (mtc.mt_op == MTBSF || mtc.mt_op == MTBSFM)
3409 mtc.mt_count++;
3410 STps->rw = ST_IDLE;
3411 }
3412
3413 } else {
3414 /*
3415 * If there was a bus reset, block further access
3416 * to this device. If the user wants to rewind the tape,
3417 * then reset the flag and allow access again.
3418 */
3419 if (mtc.mt_op != MTREW &&
3420 mtc.mt_op != MTOFFL &&
3421 mtc.mt_op != MTRETEN &&
3422 mtc.mt_op != MTERASE &&
3423 mtc.mt_op != MTSEEK &&
3424 mtc.mt_op != MTEOM) {
3425 retval = (-EIO);
3426 goto out;
3427 }
3428 reset_state(STp);
3429 /* remove this when the midlevel properly clears was_reset */
3430 STp->device->was_reset = 0;
3431 }
3432
3433 if (mtc.mt_op != MTNOP && mtc.mt_op != MTSETBLK &&
3434 mtc.mt_op != MTSETDENSITY && mtc.mt_op != MTWSM &&
3435 mtc.mt_op != MTSETDRVBUFFER && mtc.mt_op != MTSETPART)
3436 STps->rw = ST_IDLE; /* Prevent automatic WEOF and fsf */
3437
3438 if (mtc.mt_op == MTOFFL && STp->door_locked != ST_UNLOCKED)
3439 do_door_lock(STp, 0); /* Ignore result! */
3440
3441 if (mtc.mt_op == MTSETDRVBUFFER &&
3442 (mtc.mt_count & MT_ST_OPTIONS) != 0) {
3443 retval = st_set_options(STp, mtc.mt_count);
3444 goto out;
3445 }
3446
3447 if (mtc.mt_op == MTSETPART) {
3448 if (!STp->can_partitions ||
3449 mtc.mt_count < 0 || mtc.mt_count >= ST_NBR_PARTITIONS) {
3450 retval = (-EINVAL);
3451 goto out;
3452 }
3453 if (mtc.mt_count >= STp->nbr_partitions &&
3454 (STp->nbr_partitions = nbr_partitions(STp)) < 0) {
3455 retval = (-EIO);
3456 goto out;
3457 }
3458 if (mtc.mt_count >= STp->nbr_partitions) {
3459 retval = (-EINVAL);
3460 goto out;
3461 }
3462 STp->new_partition = mtc.mt_count;
3463 retval = 0;
3464 goto out;
3465 }
3466
3467 if (mtc.mt_op == MTMKPART) {
3468 if (!STp->can_partitions) {
3469 retval = (-EINVAL);
3470 goto out;
3471 }
3472 if ((i = st_int_ioctl(STp, MTREW, 0)) < 0 ||
3473 (i = partition_tape(STp, mtc.mt_count)) < 0) {
3474 retval = i;
3475 goto out;
3476 }
3477 for (i = 0; i < ST_NBR_PARTITIONS; i++) {
3478 STp->ps[i].rw = ST_IDLE;
3479 STp->ps[i].at_sm = 0;
3480 STp->ps[i].last_block_valid = 0;
3481 }
3482 STp->partition = STp->new_partition = 0;
3483 STp->nbr_partitions = 1; /* Bad guess ?-) */
3484 STps->drv_block = STps->drv_file = 0;
3485 retval = 0;
3486 goto out;
3487 }
3488
3489 if (mtc.mt_op == MTSEEK) {
3490 i = set_location(STp, mtc.mt_count, STp->new_partition, 0);
3491 if (!STp->can_partitions)
3492 STp->ps[0].rw = ST_IDLE;
3493 retval = i;
3494 goto out;
3495 }
3496
3497 if (mtc.mt_op == MTUNLOAD || mtc.mt_op == MTOFFL) {
3498 retval = do_load_unload(STp, file, 0);
3499 goto out;
3500 }
3501
3502 if (mtc.mt_op == MTLOAD) {
3503 retval = do_load_unload(STp, file, max(1, mtc.mt_count));
3504 goto out;
3505 }
3506
3507 if (mtc.mt_op == MTLOCK || mtc.mt_op == MTUNLOCK) {
3508 retval = do_door_lock(STp, (mtc.mt_op == MTLOCK));
3509 goto out;
3510 }
3511
3512 if (STp->can_partitions && STp->ready == ST_READY &&
3513 (i = switch_partition(STp)) < 0) {
3514 retval = i;
3515 goto out;
3516 }
3517
3518 if (mtc.mt_op == MTCOMPRESSION)
3519 retval = st_compression(STp, (mtc.mt_count & 1));
3520 else
3521 retval = st_int_ioctl(STp, mtc.mt_op, mtc.mt_count);
3522 goto out;
3523 }
3524 if (!STm->defined) {
3525 retval = (-ENXIO);
3526 goto out;
3527 }
3528
3529 if ((i = flush_buffer(STp, 0)) < 0) {
3530 retval = i;
3531 goto out;
3532 }
3533 if (STp->can_partitions &&
3534 (i = switch_partition(STp)) < 0) {
3535 retval = i;
3536 goto out;
3537 }
3538
3539 if (cmd_type == _IOC_TYPE(MTIOCGET) && cmd_nr == _IOC_NR(MTIOCGET)) {
3540 struct mtget mt_status;
3541
3542 if (_IOC_SIZE(cmd_in) != sizeof(struct mtget)) {
3543 retval = (-EINVAL);
3544 goto out;
3545 }
3546
3547 mt_status.mt_type = STp->tape_type;
3548 mt_status.mt_dsreg =
3549 ((STp->block_size << MT_ST_BLKSIZE_SHIFT) & MT_ST_BLKSIZE_MASK) |
3550 ((STp->density << MT_ST_DENSITY_SHIFT) & MT_ST_DENSITY_MASK);
3551 mt_status.mt_blkno = STps->drv_block;
3552 mt_status.mt_fileno = STps->drv_file;
3553 if (STp->block_size != 0) {
3554 if (STps->rw == ST_WRITING)
3555 mt_status.mt_blkno +=
3556 (STp->buffer)->buffer_bytes / STp->block_size;
3557 else if (STps->rw == ST_READING)
3558 mt_status.mt_blkno -=
3559 ((STp->buffer)->buffer_bytes +
3560 STp->block_size - 1) / STp->block_size;
3561 }
3562
3563 mt_status.mt_gstat = 0;
3564 if (STp->drv_write_prot)
3565 mt_status.mt_gstat |= GMT_WR_PROT(0xffffffff);
3566 if (mt_status.mt_blkno == 0) {
3567 if (mt_status.mt_fileno == 0)
3568 mt_status.mt_gstat |= GMT_BOT(0xffffffff);
3569 else
3570 mt_status.mt_gstat |= GMT_EOF(0xffffffff);
3571 }
3572 mt_status.mt_erreg = (STp->recover_reg << MT_ST_SOFTERR_SHIFT);
3573 mt_status.mt_resid = STp->partition;
3574 if (STps->eof == ST_EOM_OK || STps->eof == ST_EOM_ERROR)
3575 mt_status.mt_gstat |= GMT_EOT(0xffffffff);
3576 else if (STps->eof >= ST_EOM_OK)
3577 mt_status.mt_gstat |= GMT_EOD(0xffffffff);
3578 if (STp->density == 1)
3579 mt_status.mt_gstat |= GMT_D_800(0xffffffff);
3580 else if (STp->density == 2)
3581 mt_status.mt_gstat |= GMT_D_1600(0xffffffff);
3582 else if (STp->density == 3)
3583 mt_status.mt_gstat |= GMT_D_6250(0xffffffff);
3584 if (STp->ready == ST_READY)
3585 mt_status.mt_gstat |= GMT_ONLINE(0xffffffff);
3586 if (STp->ready == ST_NO_TAPE)
3587 mt_status.mt_gstat |= GMT_DR_OPEN(0xffffffff);
3588 if (STps->at_sm)
3589 mt_status.mt_gstat |= GMT_SM(0xffffffff);
3590 if (STm->do_async_writes ||
3591 (STm->do_buffer_writes && STp->block_size != 0) ||
3592 STp->drv_buffer != 0)
3593 mt_status.mt_gstat |= GMT_IM_REP_EN(0xffffffff);
3594 if (STp->cleaning_req)
3595 mt_status.mt_gstat |= GMT_CLN(0xffffffff);
3596
3597 i = copy_to_user(p, &mt_status, sizeof(struct mtget));
3598 if (i) {
3599 retval = (-EFAULT);
3600 goto out;
3601 }
3602
3603 STp->recover_reg = 0; /* Clear after read */
3604 retval = 0;
3605 goto out;
3606 } /* End of MTIOCGET */
3607 if (cmd_type == _IOC_TYPE(MTIOCPOS) && cmd_nr == _IOC_NR(MTIOCPOS)) {
3608 struct mtpos mt_pos;
3609 if (_IOC_SIZE(cmd_in) != sizeof(struct mtpos)) {
3610 retval = (-EINVAL);
3611 goto out;
3612 }
3613 if ((i = get_location(STp, &blk, &bt, 0)) < 0) {
3614 retval = i;
3615 goto out;
3616 }
3617 mt_pos.mt_blkno = blk;
3618 i = copy_to_user(p, &mt_pos, sizeof(struct mtpos));
3619 if (i)
3620 retval = (-EFAULT);
3621 goto out;
3622 }
3623 mutex_unlock(&STp->lock);
3624 switch (cmd_in) {
3625 case SCSI_IOCTL_GET_IDLUN:
3626 case SCSI_IOCTL_GET_BUS_NUMBER:
3627 break;
3628 default:
3629 if ((cmd_in == SG_IO ||
3630 cmd_in == SCSI_IOCTL_SEND_COMMAND ||
3631 cmd_in == CDROM_SEND_PACKET) &&
3632 !capable(CAP_SYS_RAWIO))
3633 i = -EPERM;
3634 else
3635 i = scsi_cmd_ioctl(STp->disk->queue, STp->disk,
3636 file->f_mode, cmd_in, p);
3637 if (i != -ENOTTY)
3638 return i;
3639 break;
3640 }
3641 retval = scsi_ioctl(STp->device, cmd_in, p);
3642 if (!retval && cmd_in == SCSI_IOCTL_STOP_UNIT) { /* unload */
3643 STp->rew_at_close = 0;
3644 STp->ready = ST_NO_TAPE;
3645 }
3646 return retval;
3647
3648 out:
3649 mutex_unlock(&STp->lock);
3650 return retval;
3651 }
3652
3653 #ifdef CONFIG_COMPAT
3654 static long st_compat_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
3655 {
3656 struct scsi_tape *STp = file->private_data;
3657 struct scsi_device *sdev = STp->device;
3658 int ret = -ENOIOCTLCMD;
3659 if (sdev->host->hostt->compat_ioctl) {
3660
3661 ret = sdev->host->hostt->compat_ioctl(sdev, cmd, (void __user *)arg);
3662
3663 }
3664 return ret;
3665 }
3666 #endif
3667
3668
3669
3670 /* Try to allocate a new tape buffer. Calling function must not hold
3671 dev_arr_lock. */
3672 static struct st_buffer *new_tape_buffer(int need_dma, int max_sg)
3673 {
3674 struct st_buffer *tb;
3675
3676 tb = kzalloc(sizeof(struct st_buffer), GFP_ATOMIC);
3677 if (!tb) {
3678 printk(KERN_NOTICE "st: Can't allocate new tape buffer.\n");
3679 return NULL;
3680 }
3681 tb->frp_segs = 0;
3682 tb->use_sg = max_sg;
3683 tb->dma = need_dma;
3684 tb->buffer_size = 0;
3685
3686 tb->reserved_pages = kzalloc(max_sg * sizeof(struct page *),
3687 GFP_ATOMIC);
3688 if (!tb->reserved_pages) {
3689 kfree(tb);
3690 return NULL;
3691 }
3692
3693 return tb;
3694 }
3695
3696
3697 /* Try to allocate enough space in the tape buffer */
3698 #define ST_MAX_ORDER 6
3699
3700 static int enlarge_buffer(struct st_buffer * STbuffer, int new_size, int need_dma)
3701 {
3702 int segs, nbr, max_segs, b_size, order, got;
3703 gfp_t priority;
3704
3705 if (new_size <= STbuffer->buffer_size)
3706 return 1;
3707
3708 if (STbuffer->buffer_size <= PAGE_SIZE)
3709 normalize_buffer(STbuffer); /* Avoid extra segment */
3710
3711 max_segs = STbuffer->use_sg;
3712 nbr = max_segs - STbuffer->frp_segs;
3713 if (nbr <= 0)
3714 return 0;
3715
3716 priority = GFP_KERNEL | __GFP_NOWARN;
3717 if (need_dma)
3718 priority |= GFP_DMA;
3719
3720 if (STbuffer->cleared)
3721 priority |= __GFP_ZERO;
3722
3723 if (STbuffer->frp_segs) {
3724 order = STbuffer->map_data.page_order;
3725 b_size = PAGE_SIZE << order;
3726 } else {
3727 for (b_size = PAGE_SIZE, order = 0;
3728 order < ST_MAX_ORDER && b_size < new_size;
3729 order++, b_size *= 2)
3730 ; /* empty */
3731 }
3732 if (max_segs * (PAGE_SIZE << order) < new_size) {
3733 if (order == ST_MAX_ORDER)
3734 return 0;
3735 normalize_buffer(STbuffer);
3736 return enlarge_buffer(STbuffer, new_size, need_dma);
3737 }
3738
3739 for (segs = STbuffer->frp_segs, got = STbuffer->buffer_size;
3740 segs < max_segs && got < new_size;) {
3741 struct page *page;
3742
3743 page = alloc_pages(priority, order);
3744 if (!page) {
3745 DEB(STbuffer->buffer_size = got);
3746 normalize_buffer(STbuffer);
3747 return 0;
3748 }
3749
3750 STbuffer->frp_segs += 1;
3751 got += b_size;
3752 STbuffer->buffer_size = got;
3753 STbuffer->reserved_pages[segs] = page;
3754 segs++;
3755 }
3756 STbuffer->b_data = page_address(STbuffer->reserved_pages[0]);
3757 STbuffer->map_data.page_order = order;
3758
3759 return 1;
3760 }
3761
3762
3763 /* Make sure that no data from previous user is in the internal buffer */
3764 static void clear_buffer(struct st_buffer * st_bp)
3765 {
3766 int i;
3767
3768 for (i=0; i < st_bp->frp_segs; i++)
3769 memset(page_address(st_bp->reserved_pages[i]), 0,
3770 PAGE_SIZE << st_bp->map_data.page_order);
3771 st_bp->cleared = 1;
3772 }
3773
3774
3775 /* Release the extra buffer */
3776 static void normalize_buffer(struct st_buffer * STbuffer)
3777 {
3778 int i, order = STbuffer->map_data.page_order;
3779
3780 for (i = 0; i < STbuffer->frp_segs; i++) {
3781 __free_pages(STbuffer->reserved_pages[i], order);
3782 STbuffer->buffer_size -= (PAGE_SIZE << order);
3783 }
3784 STbuffer->frp_segs = 0;
3785 STbuffer->sg_segs = 0;
3786 STbuffer->map_data.page_order = 0;
3787 STbuffer->map_data.offset = 0;
3788 }
3789
3790
3791 /* Move data from the user buffer to the tape buffer. Returns zero (success) or
3792 negative error code. */
3793 static int append_to_buffer(const char __user *ubp, struct st_buffer * st_bp, int do_count)
3794 {
3795 int i, cnt, res, offset;
3796 int length = PAGE_SIZE << st_bp->map_data.page_order;
3797
3798 for (i = 0, offset = st_bp->buffer_bytes;
3799 i < st_bp->frp_segs && offset >= length; i++)
3800 offset -= length;
3801 if (i == st_bp->frp_segs) { /* Should never happen */
3802 printk(KERN_WARNING "st: append_to_buffer offset overflow.\n");
3803 return (-EIO);
3804 }
3805 for (; i < st_bp->frp_segs && do_count > 0; i++) {
3806 struct page *page = st_bp->reserved_pages[i];
3807 cnt = length - offset < do_count ? length - offset : do_count;
3808 res = copy_from_user(page_address(page) + offset, ubp, cnt);
3809 if (res)
3810 return (-EFAULT);
3811 do_count -= cnt;
3812 st_bp->buffer_bytes += cnt;
3813 ubp += cnt;
3814 offset = 0;
3815 }
3816 if (do_count) /* Should never happen */
3817 return (-EIO);
3818
3819 return 0;
3820 }
3821
3822
3823 /* Move data from the tape buffer to the user buffer. Returns zero (success) or
3824 negative error code. */
3825 static int from_buffer(struct st_buffer * st_bp, char __user *ubp, int do_count)