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Merge branch 'for-linus' of git://git.infradead.org/users/sameo/mfd-2.6
[linux-btrfs-devel.git] / drivers / scsi / st.c
blob1871b8ae83ae7031f73084470278c7a89ce8da96
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 - 2010 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 = "20101219";
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/slab.h>
31 #include <linux/errno.h>
32 #include <linux/mtio.h>
33 #include <linux/cdrom.h>
34 #include <linux/ioctl.h>
35 #include <linux/fcntl.h>
36 #include <linux/spinlock.h>
37 #include <linux/blkdev.h>
38 #include <linux/moduleparam.h>
39 #include <linux/cdev.h>
40 #include <linux/delay.h>
41 #include <linux/mutex.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 DEFINE_MUTEX(st_mutex);
79 static int buffer_kbs;
80 static int max_sg_segs;
81 static int try_direct_io = TRY_DIRECT_IO;
82 static int try_rdio = 1;
83 static int try_wdio = 1;
84
85 static int st_dev_max;
86 static int st_nr_dev;
87
88 static struct class *st_sysfs_class;
89
90 MODULE_AUTHOR("Kai Makisara");
91 MODULE_DESCRIPTION("SCSI tape (st) driver");
92 MODULE_LICENSE("GPL");
93 MODULE_ALIAS_CHARDEV_MAJOR(SCSI_TAPE_MAJOR);
94 MODULE_ALIAS_SCSI_DEVICE(TYPE_TAPE);
95
96 /* Set 'perm' (4th argument) to 0 to disable module_param's definition
97 * of sysfs parameters (which module_param doesn't yet support).
98 * Sysfs parameters defined explicitly later.
99 */
100 module_param_named(buffer_kbs, buffer_kbs, int, 0);
101 MODULE_PARM_DESC(buffer_kbs, "Default driver buffer size for fixed block mode (KB; 32)");
102 module_param_named(max_sg_segs, max_sg_segs, int, 0);
103 MODULE_PARM_DESC(max_sg_segs, "Maximum number of scatter/gather segments to use (256)");
104 module_param_named(try_direct_io, try_direct_io, int, 0);
105 MODULE_PARM_DESC(try_direct_io, "Try direct I/O between user buffer and tape drive (1)");
106
107 /* Extra parameters for testing */
108 module_param_named(try_rdio, try_rdio, int, 0);
109 MODULE_PARM_DESC(try_rdio, "Try direct read i/o when possible");
110 module_param_named(try_wdio, try_wdio, int, 0);
111 MODULE_PARM_DESC(try_wdio, "Try direct write i/o when possible");
112
113 #ifndef MODULE
114 static int write_threshold_kbs; /* retained for compatibility */
115 static struct st_dev_parm {
116 char *name;
117 int *val;
118 } parms[] __initdata = {
119 {
120 "buffer_kbs", &buffer_kbs
121 },
122 { /* Retained for compatibility with 2.4 */
123 "write_threshold_kbs", &write_threshold_kbs
124 },
125 {
126 "max_sg_segs", NULL
127 },
128 {
129 "try_direct_io", &try_direct_io
130 }
131 };
132 #endif
133
134 /* Restrict the number of modes so that names for all are assigned */
135 #if ST_NBR_MODES > 16
136 #error "Maximum number of modes is 16"
137 #endif
138 /* Bit reversed order to get same names for same minors with all
139 mode counts */
140 static const char *st_formats[] = {
141 "", "r", "k", "s", "l", "t", "o", "u",
142 "m", "v", "p", "x", "a", "y", "q", "z"};
143
144 /* The default definitions have been moved to st_options.h */
145
146 #define ST_FIXED_BUFFER_SIZE (ST_FIXED_BUFFER_BLOCKS * ST_KILOBYTE)
147
148 /* The buffer size should fit into the 24 bits for length in the
149 6-byte SCSI read and write commands. */
150 #if ST_FIXED_BUFFER_SIZE >= (2 << 24 - 1)
151 #error "Buffer size should not exceed (2 << 24 - 1) bytes!"
152 #endif
153
154 static int debugging = DEBUG;
155
156 #define MAX_RETRIES 0
157 #define MAX_WRITE_RETRIES 0
158 #define MAX_READY_RETRIES 0
159 #define NO_TAPE NOT_READY
160
161 #define ST_TIMEOUT (900 * HZ)
162 #define ST_LONG_TIMEOUT (14000 * HZ)
163
164 /* Remove mode bits and auto-rewind bit (7) */
165 #define TAPE_NR(x) ( ((iminor(x) & ~255) >> (ST_NBR_MODE_BITS + 1)) | \
166 (iminor(x) & ~(-1 << ST_MODE_SHIFT)) )
167 #define TAPE_MODE(x) ((iminor(x) & ST_MODE_MASK) >> ST_MODE_SHIFT)
168
169 /* Construct the minor number from the device (d), mode (m), and non-rewind (n) data */
170 #define TAPE_MINOR(d, m, n) (((d & ~(255 >> (ST_NBR_MODE_BITS + 1))) << (ST_NBR_MODE_BITS + 1)) | \
171 (d & (255 >> (ST_NBR_MODE_BITS + 1))) | (m << ST_MODE_SHIFT) | ((n != 0) << 7) )
172
173 /* Internal ioctl to set both density (uppermost 8 bits) and blocksize (lower
174 24 bits) */
175 #define SET_DENS_AND_BLK 0x10001
176
177 static DEFINE_RWLOCK(st_dev_arr_lock);
178
179 static int st_fixed_buffer_size = ST_FIXED_BUFFER_SIZE;
180 static int st_max_sg_segs = ST_MAX_SG;
181
182 static struct scsi_tape **scsi_tapes = NULL;
183
184 static int modes_defined;
185
186 static int enlarge_buffer(struct st_buffer *, int, int);
187 static void clear_buffer(struct st_buffer *);
188 static void normalize_buffer(struct st_buffer *);
189 static int append_to_buffer(const char __user *, struct st_buffer *, int);
190 static int from_buffer(struct st_buffer *, char __user *, int);
191 static void move_buffer_data(struct st_buffer *, int);
192
193 static int sgl_map_user_pages(struct st_buffer *, const unsigned int,
194 unsigned long, size_t, int);
195 static int sgl_unmap_user_pages(struct st_buffer *, const unsigned int, int);
196
197 static int st_probe(struct device *);
198 static int st_remove(struct device *);
199
200 static int do_create_sysfs_files(void);
201 static void do_remove_sysfs_files(void);
202 static int do_create_class_files(struct scsi_tape *, int, int);
203
204 static struct scsi_driver st_template = {
205 .owner = THIS_MODULE,
206 .gendrv = {
207 .name = "st",
208 .probe = st_probe,
209 .remove = st_remove,
210 },
211 };
212
213 static int st_compression(struct scsi_tape *, int);
214
215 static int find_partition(struct scsi_tape *);
216 static int switch_partition(struct scsi_tape *);
217
218 static int st_int_ioctl(struct scsi_tape *, unsigned int, unsigned long);
219
220 static void scsi_tape_release(struct kref *);
221
222 #define to_scsi_tape(obj) container_of(obj, struct scsi_tape, kref)
223
224 static DEFINE_MUTEX(st_ref_mutex);
225
226 \f
227 #include "osst_detect.h"
228 #ifndef SIGS_FROM_OSST
229 #define SIGS_FROM_OSST \
230 {"OnStream", "SC-", "", "osst"}, \
231 {"OnStream", "DI-", "", "osst"}, \
232 {"OnStream", "DP-", "", "osst"}, \
233 {"OnStream", "USB", "", "osst"}, \
234 {"OnStream", "FW-", "", "osst"}
235 #endif
236
237 static struct scsi_tape *scsi_tape_get(int dev)
238 {
239 struct scsi_tape *STp = NULL;
240
241 mutex_lock(&st_ref_mutex);
242 write_lock(&st_dev_arr_lock);
243
244 if (dev < st_dev_max && scsi_tapes != NULL)
245 STp = scsi_tapes[dev];
246 if (!STp) goto out;
247
248 kref_get(&STp->kref);
249
250 if (!STp->device)
251 goto out_put;
252
253 if (scsi_device_get(STp->device))
254 goto out_put;
255
256 goto out;
257
258 out_put:
259 kref_put(&STp->kref, scsi_tape_release);
260 STp = NULL;
261 out:
262 write_unlock(&st_dev_arr_lock);
263 mutex_unlock(&st_ref_mutex);
264 return STp;
265 }
266
267 static void scsi_tape_put(struct scsi_tape *STp)
268 {
269 struct scsi_device *sdev = STp->device;
270
271 mutex_lock(&st_ref_mutex);
272 kref_put(&STp->kref, scsi_tape_release);
273 scsi_device_put(sdev);
274 mutex_unlock(&st_ref_mutex);
275 }
276
277 struct st_reject_data {
278 char *vendor;
279 char *model;
280 char *rev;
281 char *driver_hint; /* Name of the correct driver, NULL if unknown */
282 };
283
284 static struct st_reject_data reject_list[] = {
285 /* {"XXX", "Yy-", "", NULL}, example */
286 SIGS_FROM_OSST,
287 {NULL, }};
288
289 /* If the device signature is on the list of incompatible drives, the
290 function returns a pointer to the name of the correct driver (if known) */
291 static char * st_incompatible(struct scsi_device* SDp)
292 {
293 struct st_reject_data *rp;
294
295 for (rp=&(reject_list[0]); rp->vendor != NULL; rp++)
296 if (!strncmp(rp->vendor, SDp->vendor, strlen(rp->vendor)) &&
297 !strncmp(rp->model, SDp->model, strlen(rp->model)) &&
298 !strncmp(rp->rev, SDp->rev, strlen(rp->rev))) {
299 if (rp->driver_hint)
300 return rp->driver_hint;
301 else
302 return "unknown";
303 }
304 return NULL;
305 }
306 \f
307
308 static inline char *tape_name(struct scsi_tape *tape)
309 {
310 return tape->disk->disk_name;
311 }
312
313
314 static void st_analyze_sense(struct st_request *SRpnt, struct st_cmdstatus *s)
315 {
316 const u8 *ucp;
317 const u8 *sense = SRpnt->sense;
318
319 s->have_sense = scsi_normalize_sense(SRpnt->sense,
320 SCSI_SENSE_BUFFERSIZE, &s->sense_hdr);
321 s->flags = 0;
322
323 if (s->have_sense) {
324 s->deferred = 0;
325 s->remainder_valid =
326 scsi_get_sense_info_fld(sense, SCSI_SENSE_BUFFERSIZE, &s->uremainder64);
327 switch (sense[0] & 0x7f) {
328 case 0x71:
329 s->deferred = 1;
330 case 0x70:
331 s->fixed_format = 1;
332 s->flags = sense[2] & 0xe0;
333 break;
334 case 0x73:
335 s->deferred = 1;
336 case 0x72:
337 s->fixed_format = 0;
338 ucp = scsi_sense_desc_find(sense, SCSI_SENSE_BUFFERSIZE, 4);
339 s->flags = ucp ? (ucp[3] & 0xe0) : 0;
340 break;
341 }
342 }
343 }
344
345
346 /* Convert the result to success code */
347 static int st_chk_result(struct scsi_tape *STp, struct st_request * SRpnt)
348 {
349 int result = SRpnt->result;
350 u8 scode;
351 DEB(const char *stp;)
352 char *name = tape_name(STp);
353 struct st_cmdstatus *cmdstatp;
354
355 if (!result)
356 return 0;
357
358 cmdstatp = &STp->buffer->cmdstat;
359 st_analyze_sense(SRpnt, cmdstatp);
360
361 if (cmdstatp->have_sense)
362 scode = STp->buffer->cmdstat.sense_hdr.sense_key;
363 else
364 scode = 0;
365
366 DEB(
367 if (debugging) {
368 printk(ST_DEB_MSG "%s: Error: %x, cmd: %x %x %x %x %x %x\n",
369 name, result,
370 SRpnt->cmd[0], SRpnt->cmd[1], SRpnt->cmd[2],
371 SRpnt->cmd[3], SRpnt->cmd[4], SRpnt->cmd[5]);
372 if (cmdstatp->have_sense)
373 __scsi_print_sense(name, SRpnt->sense, SCSI_SENSE_BUFFERSIZE);
374 } ) /* end DEB */
375 if (!debugging) { /* Abnormal conditions for tape */
376 if (!cmdstatp->have_sense)
377 printk(KERN_WARNING
378 "%s: Error %x (driver bt 0x%x, host bt 0x%x).\n",
379 name, result, driver_byte(result),
380 host_byte(result));
381 else if (cmdstatp->have_sense &&
382 scode != NO_SENSE &&
383 scode != RECOVERED_ERROR &&
384 /* scode != UNIT_ATTENTION && */
385 scode != BLANK_CHECK &&
386 scode != VOLUME_OVERFLOW &&
387 SRpnt->cmd[0] != MODE_SENSE &&
388 SRpnt->cmd[0] != TEST_UNIT_READY) {
389
390 __scsi_print_sense(name, SRpnt->sense, SCSI_SENSE_BUFFERSIZE);
391 }
392 }
393
394 if (cmdstatp->fixed_format &&
395 STp->cln_mode >= EXTENDED_SENSE_START) { /* Only fixed format sense */
396 if (STp->cln_sense_value)
397 STp->cleaning_req |= ((SRpnt->sense[STp->cln_mode] &
398 STp->cln_sense_mask) == STp->cln_sense_value);
399 else
400 STp->cleaning_req |= ((SRpnt->sense[STp->cln_mode] &
401 STp->cln_sense_mask) != 0);
402 }
403 if (cmdstatp->have_sense &&
404 cmdstatp->sense_hdr.asc == 0 && cmdstatp->sense_hdr.ascq == 0x17)
405 STp->cleaning_req = 1; /* ASC and ASCQ => cleaning requested */
406
407 STp->pos_unknown |= STp->device->was_reset;
408
409 if (cmdstatp->have_sense &&
410 scode == RECOVERED_ERROR
411 #if ST_RECOVERED_WRITE_FATAL
412 && SRpnt->cmd[0] != WRITE_6
413 && SRpnt->cmd[0] != WRITE_FILEMARKS
414 #endif
415 ) {
416 STp->recover_count++;
417 STp->recover_reg++;
418
419 DEB(
420 if (debugging) {
421 if (SRpnt->cmd[0] == READ_6)
422 stp = "read";
423 else if (SRpnt->cmd[0] == WRITE_6)
424 stp = "write";
425 else
426 stp = "ioctl";
427 printk(ST_DEB_MSG "%s: Recovered %s error (%d).\n", name, stp,
428 STp->recover_count);
429 } ) /* end DEB */
430
431 if (cmdstatp->flags == 0)
432 return 0;
433 }
434 return (-EIO);
435 }
436
437 static struct st_request *st_allocate_request(struct scsi_tape *stp)
438 {
439 struct st_request *streq;
440
441 streq = kzalloc(sizeof(*streq), GFP_KERNEL);
442 if (streq)
443 streq->stp = stp;
444 else {
445 DEBC(printk(KERN_ERR "%s: Can't get SCSI request.\n",
446 tape_name(stp)););
447 if (signal_pending(current))
448 stp->buffer->syscall_result = -EINTR;
449 else
450 stp->buffer->syscall_result = -EBUSY;
451 }
452
453 return streq;
454 }
455
456 static void st_release_request(struct st_request *streq)
457 {
458 kfree(streq);
459 }
460
461 static void st_scsi_execute_end(struct request *req, int uptodate)
462 {
463 struct st_request *SRpnt = req->end_io_data;
464 struct scsi_tape *STp = SRpnt->stp;
465
466 STp->buffer->cmdstat.midlevel_result = SRpnt->result = req->errors;
467 STp->buffer->cmdstat.residual = req->resid_len;
468
469 if (SRpnt->waiting)
470 complete(SRpnt->waiting);
471
472 blk_rq_unmap_user(SRpnt->bio);
473 __blk_put_request(req->q, req);
474 }
475
476 static int st_scsi_execute(struct st_request *SRpnt, const unsigned char *cmd,
477 int data_direction, void *buffer, unsigned bufflen,
478 int timeout, int retries)
479 {
480 struct request *req;
481 struct rq_map_data *mdata = &SRpnt->stp->buffer->map_data;
482 int err = 0;
483 int write = (data_direction == DMA_TO_DEVICE);
484
485 req = blk_get_request(SRpnt->stp->device->request_queue, write,
486 GFP_KERNEL);
487 if (!req)
488 return DRIVER_ERROR << 24;
489
490 req->cmd_type = REQ_TYPE_BLOCK_PC;
491 req->cmd_flags |= REQ_QUIET;
492
493 mdata->null_mapped = 1;
494
495 if (bufflen) {
496 err = blk_rq_map_user(req->q, req, mdata, NULL, bufflen,
497 GFP_KERNEL);
498 if (err) {
499 blk_put_request(req);
500 return DRIVER_ERROR << 24;
501 }
502 }
503
504 SRpnt->bio = req->bio;
505 req->cmd_len = COMMAND_SIZE(cmd[0]);
506 memset(req->cmd, 0, BLK_MAX_CDB);
507 memcpy(req->cmd, cmd, req->cmd_len);
508 req->sense = SRpnt->sense;
509 req->sense_len = 0;
510 req->timeout = timeout;
511 req->retries = retries;
512 req->end_io_data = SRpnt;
513
514 blk_execute_rq_nowait(req->q, NULL, req, 1, st_scsi_execute_end);
515 return 0;
516 }
517
518 /* Do the scsi command. Waits until command performed if do_wait is true.
519 Otherwise write_behind_check() is used to check that the command
520 has finished. */
521 static struct st_request *
522 st_do_scsi(struct st_request * SRpnt, struct scsi_tape * STp, unsigned char *cmd,
523 int bytes, int direction, int timeout, int retries, int do_wait)
524 {
525 struct completion *waiting;
526 struct rq_map_data *mdata = &STp->buffer->map_data;
527 int ret;
528
529 /* if async, make sure there's no command outstanding */
530 if (!do_wait && ((STp->buffer)->last_SRpnt)) {
531 printk(KERN_ERR "%s: Async command already active.\n",
532 tape_name(STp));
533 if (signal_pending(current))
534 (STp->buffer)->syscall_result = (-EINTR);
535 else
536 (STp->buffer)->syscall_result = (-EBUSY);
537 return NULL;
538 }
539
540 if (!SRpnt) {
541 SRpnt = st_allocate_request(STp);
542 if (!SRpnt)
543 return NULL;
544 }
545
546 /* If async IO, set last_SRpnt. This ptr tells write_behind_check
547 which IO is outstanding. It's nulled out when the IO completes. */
548 if (!do_wait)
549 (STp->buffer)->last_SRpnt = SRpnt;
550
551 waiting = &STp->wait;
552 init_completion(waiting);
553 SRpnt->waiting = waiting;
554
555 if (STp->buffer->do_dio) {
556 mdata->page_order = 0;
557 mdata->nr_entries = STp->buffer->sg_segs;
558 mdata->pages = STp->buffer->mapped_pages;
559 } else {
560 mdata->page_order = STp->buffer->reserved_page_order;
561 mdata->nr_entries =
562 DIV_ROUND_UP(bytes, PAGE_SIZE << mdata->page_order);
563 mdata->pages = STp->buffer->reserved_pages;
564 mdata->offset = 0;
565 }
566
567 memcpy(SRpnt->cmd, cmd, sizeof(SRpnt->cmd));
568 STp->buffer->cmdstat.have_sense = 0;
569 STp->buffer->syscall_result = 0;
570
571 ret = st_scsi_execute(SRpnt, cmd, direction, NULL, bytes, timeout,
572 retries);
573 if (ret) {
574 /* could not allocate the buffer or request was too large */
575 (STp->buffer)->syscall_result = (-EBUSY);
576 (STp->buffer)->last_SRpnt = NULL;
577 } else if (do_wait) {
578 wait_for_completion(waiting);
579 SRpnt->waiting = NULL;
580 (STp->buffer)->syscall_result = st_chk_result(STp, SRpnt);
581 }
582
583 return SRpnt;
584 }
585
586
587 /* Handle the write-behind checking (waits for completion). Returns -ENOSPC if
588 write has been correct but EOM early warning reached, -EIO if write ended in
589 error or zero if write successful. Asynchronous writes are used only in
590 variable block mode. */
591 static int write_behind_check(struct scsi_tape * STp)
592 {
593 int retval = 0;
594 struct st_buffer *STbuffer;
595 struct st_partstat *STps;
596 struct st_cmdstatus *cmdstatp;
597 struct st_request *SRpnt;
598
599 STbuffer = STp->buffer;
600 if (!STbuffer->writing)
601 return 0;
602
603 DEB(
604 if (STp->write_pending)
605 STp->nbr_waits++;
606 else
607 STp->nbr_finished++;
608 ) /* end DEB */
609
610 wait_for_completion(&(STp->wait));
611 SRpnt = STbuffer->last_SRpnt;
612 STbuffer->last_SRpnt = NULL;
613 SRpnt->waiting = NULL;
614
615 (STp->buffer)->syscall_result = st_chk_result(STp, SRpnt);
616 st_release_request(SRpnt);
617
618 STbuffer->buffer_bytes -= STbuffer->writing;
619 STps = &(STp->ps[STp->partition]);
620 if (STps->drv_block >= 0) {
621 if (STp->block_size == 0)
622 STps->drv_block++;
623 else
624 STps->drv_block += STbuffer->writing / STp->block_size;
625 }
626
627 cmdstatp = &STbuffer->cmdstat;
628 if (STbuffer->syscall_result) {
629 retval = -EIO;
630 if (cmdstatp->have_sense && !cmdstatp->deferred &&
631 (cmdstatp->flags & SENSE_EOM) &&
632 (cmdstatp->sense_hdr.sense_key == NO_SENSE ||
633 cmdstatp->sense_hdr.sense_key == RECOVERED_ERROR)) {
634 /* EOM at write-behind, has all data been written? */
635 if (!cmdstatp->remainder_valid ||
636 cmdstatp->uremainder64 == 0)
637 retval = -ENOSPC;
638 }
639 if (retval == -EIO)
640 STps->drv_block = -1;
641 }
642 STbuffer->writing = 0;
643
644 DEB(if (debugging && retval)
645 printk(ST_DEB_MSG "%s: Async write error %x, return value %d.\n",
646 tape_name(STp), STbuffer->cmdstat.midlevel_result, retval);) /* end DEB */
647
648 return retval;
649 }
650
651
652 /* Step over EOF if it has been inadvertently crossed (ioctl not used because
653 it messes up the block number). */
654 static int cross_eof(struct scsi_tape * STp, int forward)
655 {
656 struct st_request *SRpnt;
657 unsigned char cmd[MAX_COMMAND_SIZE];
658
659 cmd[0] = SPACE;
660 cmd[1] = 0x01; /* Space FileMarks */
661 if (forward) {
662 cmd[2] = cmd[3] = 0;
663 cmd[4] = 1;
664 } else
665 cmd[2] = cmd[3] = cmd[4] = 0xff; /* -1 filemarks */
666 cmd[5] = 0;
667
668 DEBC(printk(ST_DEB_MSG "%s: Stepping over filemark %s.\n",
669 tape_name(STp), forward ? "forward" : "backward"));
670
671 SRpnt = st_do_scsi(NULL, STp, cmd, 0, DMA_NONE,
672 STp->device->request_queue->rq_timeout,
673 MAX_RETRIES, 1);
674 if (!SRpnt)
675 return (STp->buffer)->syscall_result;
676
677 st_release_request(SRpnt);
678 SRpnt = NULL;
679
680 if ((STp->buffer)->cmdstat.midlevel_result != 0)
681 printk(KERN_ERR "%s: Stepping over filemark %s failed.\n",
682 tape_name(STp), forward ? "forward" : "backward");
683
684 return (STp->buffer)->syscall_result;
685 }
686
687
688 /* Flush the write buffer (never need to write if variable blocksize). */
689 static int st_flush_write_buffer(struct scsi_tape * STp)
690 {
691 int transfer, blks;
692 int result;
693 unsigned char cmd[MAX_COMMAND_SIZE];
694 struct st_request *SRpnt;
695 struct st_partstat *STps;
696
697 result = write_behind_check(STp);
698 if (result)
699 return result;
700
701 result = 0;
702 if (STp->dirty == 1) {
703
704 transfer = STp->buffer->buffer_bytes;
705 DEBC(printk(ST_DEB_MSG "%s: Flushing %d bytes.\n",
706 tape_name(STp), transfer));
707
708 memset(cmd, 0, MAX_COMMAND_SIZE);
709 cmd[0] = WRITE_6;
710 cmd[1] = 1;
711 blks = transfer / STp->block_size;
712 cmd[2] = blks >> 16;
713 cmd[3] = blks >> 8;
714 cmd[4] = blks;
715
716 SRpnt = st_do_scsi(NULL, STp, cmd, transfer, DMA_TO_DEVICE,
717 STp->device->request_queue->rq_timeout,
718 MAX_WRITE_RETRIES, 1);
719 if (!SRpnt)
720 return (STp->buffer)->syscall_result;
721
722 STps = &(STp->ps[STp->partition]);
723 if ((STp->buffer)->syscall_result != 0) {
724 struct st_cmdstatus *cmdstatp = &STp->buffer->cmdstat;
725
726 if (cmdstatp->have_sense && !cmdstatp->deferred &&
727 (cmdstatp->flags & SENSE_EOM) &&
728 (cmdstatp->sense_hdr.sense_key == NO_SENSE ||
729 cmdstatp->sense_hdr.sense_key == RECOVERED_ERROR) &&
730 (!cmdstatp->remainder_valid ||
731 cmdstatp->uremainder64 == 0)) { /* All written at EOM early warning */
732 STp->dirty = 0;
733 (STp->buffer)->buffer_bytes = 0;
734 if (STps->drv_block >= 0)
735 STps->drv_block += blks;
736 result = (-ENOSPC);
737 } else {
738 printk(KERN_ERR "%s: Error on flush.\n",
739 tape_name(STp));
740 STps->drv_block = (-1);
741 result = (-EIO);
742 }
743 } else {
744 if (STps->drv_block >= 0)
745 STps->drv_block += blks;
746 STp->dirty = 0;
747 (STp->buffer)->buffer_bytes = 0;
748 }
749 st_release_request(SRpnt);
750 SRpnt = NULL;
751 }
752 return result;
753 }
754
755
756 /* Flush the tape buffer. The tape will be positioned correctly unless
757 seek_next is true. */
758 static int flush_buffer(struct scsi_tape *STp, int seek_next)
759 {
760 int backspace, result;
761 struct st_buffer *STbuffer;
762 struct st_partstat *STps;
763
764 STbuffer = STp->buffer;
765
766 /*
767 * If there was a bus reset, block further access
768 * to this device.
769 */
770 if (STp->pos_unknown)
771 return (-EIO);
772
773 if (STp->ready != ST_READY)
774 return 0;
775 STps = &(STp->ps[STp->partition]);
776 if (STps->rw == ST_WRITING) /* Writing */
777 return st_flush_write_buffer(STp);
778
779 if (STp->block_size == 0)
780 return 0;
781
782 backspace = ((STp->buffer)->buffer_bytes +
783 (STp->buffer)->read_pointer) / STp->block_size -
784 ((STp->buffer)->read_pointer + STp->block_size - 1) /
785 STp->block_size;
786 (STp->buffer)->buffer_bytes = 0;
787 (STp->buffer)->read_pointer = 0;
788 result = 0;
789 if (!seek_next) {
790 if (STps->eof == ST_FM_HIT) {
791 result = cross_eof(STp, 0); /* Back over the EOF hit */
792 if (!result)
793 STps->eof = ST_NOEOF;
794 else {
795 if (STps->drv_file >= 0)
796 STps->drv_file++;
797 STps->drv_block = 0;
798 }
799 }
800 if (!result && backspace > 0)
801 result = st_int_ioctl(STp, MTBSR, backspace);
802 } else if (STps->eof == ST_FM_HIT) {
803 if (STps->drv_file >= 0)
804 STps->drv_file++;
805 STps->drv_block = 0;
806 STps->eof = ST_NOEOF;
807 }
808 return result;
809
810 }
811 \f
812 /* Set the mode parameters */
813 static int set_mode_densblk(struct scsi_tape * STp, struct st_modedef * STm)
814 {
815 int set_it = 0;
816 unsigned long arg;
817 char *name = tape_name(STp);
818
819 if (!STp->density_changed &&
820 STm->default_density >= 0 &&
821 STm->default_density != STp->density) {
822 arg = STm->default_density;
823 set_it = 1;
824 } else
825 arg = STp->density;
826 arg <<= MT_ST_DENSITY_SHIFT;
827 if (!STp->blksize_changed &&
828 STm->default_blksize >= 0 &&
829 STm->default_blksize != STp->block_size) {
830 arg |= STm->default_blksize;
831 set_it = 1;
832 } else
833 arg |= STp->block_size;
834 if (set_it &&
835 st_int_ioctl(STp, SET_DENS_AND_BLK, arg)) {
836 printk(KERN_WARNING
837 "%s: Can't set default block size to %d bytes and density %x.\n",
838 name, STm->default_blksize, STm->default_density);
839 if (modes_defined)
840 return (-EINVAL);
841 }
842 return 0;
843 }
844
845
846 /* Lock or unlock the drive door. Don't use when st_request allocated. */
847 static int do_door_lock(struct scsi_tape * STp, int do_lock)
848 {
849 int retval, cmd;
850 DEB(char *name = tape_name(STp);)
851
852
853 cmd = do_lock ? SCSI_IOCTL_DOORLOCK : SCSI_IOCTL_DOORUNLOCK;
854 DEBC(printk(ST_DEB_MSG "%s: %socking drive door.\n", name,
855 do_lock ? "L" : "Unl"));
856 retval = scsi_ioctl(STp->device, cmd, NULL);
857 if (!retval) {
858 STp->door_locked = do_lock ? ST_LOCKED_EXPLICIT : ST_UNLOCKED;
859 }
860 else {
861 STp->door_locked = ST_LOCK_FAILS;
862 }
863 return retval;
864 }
865
866
867 /* Set the internal state after reset */
868 static void reset_state(struct scsi_tape *STp)
869 {
870 int i;
871 struct st_partstat *STps;
872
873 STp->pos_unknown = 0;
874 for (i = 0; i < ST_NBR_PARTITIONS; i++) {
875 STps = &(STp->ps[i]);
876 STps->rw = ST_IDLE;
877 STps->eof = ST_NOEOF;
878 STps->at_sm = 0;
879 STps->last_block_valid = 0;
880 STps->drv_block = -1;
881 STps->drv_file = -1;
882 }
883 if (STp->can_partitions) {
884 STp->partition = find_partition(STp);
885 if (STp->partition < 0)
886 STp->partition = 0;
887 STp->new_partition = STp->partition;
888 }
889 }
890 \f
891 /* Test if the drive is ready. Returns either one of the codes below or a negative system
892 error code. */
893 #define CHKRES_READY 0
894 #define CHKRES_NEW_SESSION 1
895 #define CHKRES_NOT_READY 2
896 #define CHKRES_NO_TAPE 3
897
898 #define MAX_ATTENTIONS 10
899
900 static int test_ready(struct scsi_tape *STp, int do_wait)
901 {
902 int attentions, waits, max_wait, scode;
903 int retval = CHKRES_READY, new_session = 0;
904 unsigned char cmd[MAX_COMMAND_SIZE];
905 struct st_request *SRpnt = NULL;
906 struct st_cmdstatus *cmdstatp = &STp->buffer->cmdstat;
907
908 max_wait = do_wait ? ST_BLOCK_SECONDS : 0;
909
910 for (attentions=waits=0; ; ) {
911 memset((void *) &cmd[0], 0, MAX_COMMAND_SIZE);
912 cmd[0] = TEST_UNIT_READY;
913 SRpnt = st_do_scsi(SRpnt, STp, cmd, 0, DMA_NONE,
914 STp->long_timeout, MAX_READY_RETRIES, 1);
915
916 if (!SRpnt) {
917 retval = (STp->buffer)->syscall_result;
918 break;
919 }
920
921 if (cmdstatp->have_sense) {
922
923 scode = cmdstatp->sense_hdr.sense_key;
924
925 if (scode == UNIT_ATTENTION) { /* New media? */
926 new_session = 1;
927 if (attentions < MAX_ATTENTIONS) {
928 attentions++;
929 continue;
930 }
931 else {
932 retval = (-EIO);
933 break;
934 }
935 }
936
937 if (scode == NOT_READY) {
938 if (waits < max_wait) {
939 if (msleep_interruptible(1000)) {
940 retval = (-EINTR);
941 break;
942 }
943 waits++;
944 continue;
945 }
946 else {
947 if ((STp->device)->scsi_level >= SCSI_2 &&
948 cmdstatp->sense_hdr.asc == 0x3a) /* Check ASC */
949 retval = CHKRES_NO_TAPE;
950 else
951 retval = CHKRES_NOT_READY;
952 break;
953 }
954 }
955 }
956
957 retval = (STp->buffer)->syscall_result;
958 if (!retval)
959 retval = new_session ? CHKRES_NEW_SESSION : CHKRES_READY;
960 break;
961 }
962
963 if (SRpnt != NULL)
964 st_release_request(SRpnt);
965 return retval;
966 }
967
968
969 /* See if the drive is ready and gather information about the tape. Return values:
970 < 0 negative error code from errno.h
971 0 drive ready
972 1 drive not ready (possibly no tape)
973 */
974 static int check_tape(struct scsi_tape *STp, struct file *filp)
975 {
976 int i, retval, new_session = 0, do_wait;
977 unsigned char cmd[MAX_COMMAND_SIZE], saved_cleaning;
978 unsigned short st_flags = filp->f_flags;
979 struct st_request *SRpnt = NULL;
980 struct st_modedef *STm;
981 struct st_partstat *STps;
982 char *name = tape_name(STp);
983 struct inode *inode = filp->f_path.dentry->d_inode;
984 int mode = TAPE_MODE(inode);
985
986 STp->ready = ST_READY;
987
988 if (mode != STp->current_mode) {
989 DEBC(printk(ST_DEB_MSG "%s: Mode change from %d to %d.\n",
990 name, STp->current_mode, mode));
991 new_session = 1;
992 STp->current_mode = mode;
993 }
994 STm = &(STp->modes[STp->current_mode]);
995
996 saved_cleaning = STp->cleaning_req;
997 STp->cleaning_req = 0;
998
999 do_wait = ((filp->f_flags & O_NONBLOCK) == 0);
1000 retval = test_ready(STp, do_wait);
1001
1002 if (retval < 0)
1003 goto err_out;
1004
1005 if (retval == CHKRES_NEW_SESSION) {
1006 STp->pos_unknown = 0;
1007 STp->partition = STp->new_partition = 0;
1008 if (STp->can_partitions)
1009 STp->nbr_partitions = 1; /* This guess will be updated later
1010 if necessary */
1011 for (i = 0; i < ST_NBR_PARTITIONS; i++) {
1012 STps = &(STp->ps[i]);
1013 STps->rw = ST_IDLE;
1014 STps->eof = ST_NOEOF;
1015 STps->at_sm = 0;
1016 STps->last_block_valid = 0;
1017 STps->drv_block = 0;
1018 STps->drv_file = 0;
1019 }
1020 new_session = 1;
1021 }
1022 else {
1023 STp->cleaning_req |= saved_cleaning;
1024
1025 if (retval == CHKRES_NOT_READY || retval == CHKRES_NO_TAPE) {
1026 if (retval == CHKRES_NO_TAPE)
1027 STp->ready = ST_NO_TAPE;
1028 else
1029 STp->ready = ST_NOT_READY;
1030
1031 STp->density = 0; /* Clear the erroneous "residue" */
1032 STp->write_prot = 0;
1033 STp->block_size = 0;
1034 STp->ps[0].drv_file = STp->ps[0].drv_block = (-1);
1035 STp->partition = STp->new_partition = 0;
1036 STp->door_locked = ST_UNLOCKED;
1037 return CHKRES_NOT_READY;
1038 }
1039 }
1040
1041 if (STp->omit_blklims)
1042 STp->min_block = STp->max_block = (-1);
1043 else {
1044 memset((void *) &cmd[0], 0, MAX_COMMAND_SIZE);
1045 cmd[0] = READ_BLOCK_LIMITS;
1046
1047 SRpnt = st_do_scsi(SRpnt, STp, cmd, 6, DMA_FROM_DEVICE,
1048 STp->device->request_queue->rq_timeout,
1049 MAX_READY_RETRIES, 1);
1050 if (!SRpnt) {
1051 retval = (STp->buffer)->syscall_result;
1052 goto err_out;
1053 }
1054
1055 if (!SRpnt->result && !STp->buffer->cmdstat.have_sense) {
1056 STp->max_block = ((STp->buffer)->b_data[1] << 16) |
1057 ((STp->buffer)->b_data[2] << 8) | (STp->buffer)->b_data[3];
1058 STp->min_block = ((STp->buffer)->b_data[4] << 8) |
1059 (STp->buffer)->b_data[5];
1060 if ( DEB( debugging || ) !STp->inited)
1061 printk(KERN_INFO
1062 "%s: Block limits %d - %d bytes.\n", name,
1063 STp->min_block, STp->max_block);
1064 } else {
1065 STp->min_block = STp->max_block = (-1);
1066 DEBC(printk(ST_DEB_MSG "%s: Can't read block limits.\n",
1067 name));
1068 }
1069 }
1070
1071 memset((void *) &cmd[0], 0, MAX_COMMAND_SIZE);
1072 cmd[0] = MODE_SENSE;
1073 cmd[4] = 12;
1074
1075 SRpnt = st_do_scsi(SRpnt, STp, cmd, 12, DMA_FROM_DEVICE,
1076 STp->device->request_queue->rq_timeout,
1077 MAX_READY_RETRIES, 1);
1078 if (!SRpnt) {
1079 retval = (STp->buffer)->syscall_result;
1080 goto err_out;
1081 }
1082
1083 if ((STp->buffer)->syscall_result != 0) {
1084 DEBC(printk(ST_DEB_MSG "%s: No Mode Sense.\n", name));
1085 STp->block_size = ST_DEFAULT_BLOCK; /* Educated guess (?) */
1086 (STp->buffer)->syscall_result = 0; /* Prevent error propagation */
1087 STp->drv_write_prot = 0;
1088 } else {
1089 DEBC(printk(ST_DEB_MSG
1090 "%s: Mode sense. Length %d, medium %x, WBS %x, BLL %d\n",
1091 name,
1092 (STp->buffer)->b_data[0], (STp->buffer)->b_data[1],
1093 (STp->buffer)->b_data[2], (STp->buffer)->b_data[3]));
1094
1095 if ((STp->buffer)->b_data[3] >= 8) {
1096 STp->drv_buffer = ((STp->buffer)->b_data[2] >> 4) & 7;
1097 STp->density = (STp->buffer)->b_data[4];
1098 STp->block_size = (STp->buffer)->b_data[9] * 65536 +
1099 (STp->buffer)->b_data[10] * 256 + (STp->buffer)->b_data[11];
1100 DEBC(printk(ST_DEB_MSG
1101 "%s: Density %x, tape length: %x, drv buffer: %d\n",
1102 name, STp->density, (STp->buffer)->b_data[5] * 65536 +
1103 (STp->buffer)->b_data[6] * 256 + (STp->buffer)->b_data[7],
1104 STp->drv_buffer));
1105 }
1106 STp->drv_write_prot = ((STp->buffer)->b_data[2] & 0x80) != 0;
1107 }
1108 st_release_request(SRpnt);
1109 SRpnt = NULL;
1110 STp->inited = 1;
1111
1112 if (STp->block_size > 0)
1113 (STp->buffer)->buffer_blocks =
1114 (STp->buffer)->buffer_size / STp->block_size;
1115 else
1116 (STp->buffer)->buffer_blocks = 1;
1117 (STp->buffer)->buffer_bytes = (STp->buffer)->read_pointer = 0;
1118
1119 DEBC(printk(ST_DEB_MSG
1120 "%s: Block size: %d, buffer size: %d (%d blocks).\n", name,
1121 STp->block_size, (STp->buffer)->buffer_size,
1122 (STp->buffer)->buffer_blocks));
1123
1124 if (STp->drv_write_prot) {
1125 STp->write_prot = 1;
1126
1127 DEBC(printk(ST_DEB_MSG "%s: Write protected\n", name));
1128
1129 if (do_wait &&
1130 ((st_flags & O_ACCMODE) == O_WRONLY ||
1131 (st_flags & O_ACCMODE) == O_RDWR)) {
1132 retval = (-EROFS);
1133 goto err_out;
1134 }
1135 }
1136
1137 if (STp->can_partitions && STp->nbr_partitions < 1) {
1138 /* This code is reached when the device is opened for the first time
1139 after the driver has been initialized with tape in the drive and the
1140 partition support has been enabled. */
1141 DEBC(printk(ST_DEB_MSG
1142 "%s: Updating partition number in status.\n", name));
1143 if ((STp->partition = find_partition(STp)) < 0) {
1144 retval = STp->partition;
1145 goto err_out;
1146 }
1147 STp->new_partition = STp->partition;
1148 STp->nbr_partitions = 1; /* This guess will be updated when necessary */
1149 }
1150
1151 if (new_session) { /* Change the drive parameters for the new mode */
1152 STp->density_changed = STp->blksize_changed = 0;
1153 STp->compression_changed = 0;
1154 if (!(STm->defaults_for_writes) &&
1155 (retval = set_mode_densblk(STp, STm)) < 0)
1156 goto err_out;
1157
1158 if (STp->default_drvbuffer != 0xff) {
1159 if (st_int_ioctl(STp, MTSETDRVBUFFER, STp->default_drvbuffer))
1160 printk(KERN_WARNING
1161 "%s: Can't set default drive buffering to %d.\n",
1162 name, STp->default_drvbuffer);
1163 }
1164 }
1165
1166 return CHKRES_READY;
1167
1168 err_out:
1169 return retval;
1170 }
1171
1172
1173 \f/* Open the device. Needs to take the BKL only because of incrementing the SCSI host
1174 module count. */
1175 static int st_open(struct inode *inode, struct file *filp)
1176 {
1177 int i, retval = (-EIO);
1178 struct scsi_tape *STp;
1179 struct st_partstat *STps;
1180 int dev = TAPE_NR(inode);
1181 char *name;
1182
1183 mutex_lock(&st_mutex);
1184 /*
1185 * We really want to do nonseekable_open(inode, filp); here, but some
1186 * versions of tar incorrectly call lseek on tapes and bail out if that
1187 * fails. So we disallow pread() and pwrite(), but permit lseeks.
1188 */
1189 filp->f_mode &= ~(FMODE_PREAD | FMODE_PWRITE);
1190
1191 if (!(STp = scsi_tape_get(dev))) {
1192 mutex_unlock(&st_mutex);
1193 return -ENXIO;
1194 }
1195
1196 write_lock(&st_dev_arr_lock);
1197 filp->private_data = STp;
1198 name = tape_name(STp);
1199
1200 if (STp->in_use) {
1201 write_unlock(&st_dev_arr_lock);
1202 scsi_tape_put(STp);
1203 mutex_unlock(&st_mutex);
1204 DEB( printk(ST_DEB_MSG "%s: Device already in use.\n", name); )
1205 return (-EBUSY);
1206 }
1207
1208 STp->in_use = 1;
1209 write_unlock(&st_dev_arr_lock);
1210 STp->rew_at_close = STp->autorew_dev = (iminor(inode) & 0x80) == 0;
1211
1212 if (!scsi_block_when_processing_errors(STp->device)) {
1213 retval = (-ENXIO);
1214 goto err_out;
1215 }
1216
1217 /* See that we have at least a one page buffer available */
1218 if (!enlarge_buffer(STp->buffer, PAGE_SIZE, STp->restr_dma)) {
1219 printk(KERN_WARNING "%s: Can't allocate one page tape buffer.\n",
1220 name);
1221 retval = (-EOVERFLOW);
1222 goto err_out;
1223 }
1224
1225 (STp->buffer)->cleared = 0;
1226 (STp->buffer)->writing = 0;
1227 (STp->buffer)->syscall_result = 0;
1228
1229 STp->write_prot = ((filp->f_flags & O_ACCMODE) == O_RDONLY);
1230
1231 STp->dirty = 0;
1232 for (i = 0; i < ST_NBR_PARTITIONS; i++) {
1233 STps = &(STp->ps[i]);
1234 STps->rw = ST_IDLE;
1235 }
1236 STp->try_dio_now = STp->try_dio;
1237 STp->recover_count = 0;
1238 DEB( STp->nbr_waits = STp->nbr_finished = 0;
1239 STp->nbr_requests = STp->nbr_dio = STp->nbr_pages = 0; )
1240
1241 retval = check_tape(STp, filp);
1242 if (retval < 0)
1243 goto err_out;
1244 if ((filp->f_flags & O_NONBLOCK) == 0 &&
1245 retval != CHKRES_READY) {
1246 if (STp->ready == NO_TAPE)
1247 retval = (-ENOMEDIUM);
1248 else
1249 retval = (-EIO);
1250 goto err_out;
1251 }
1252 mutex_unlock(&st_mutex);
1253 return 0;
1254
1255 err_out:
1256 normalize_buffer(STp->buffer);
1257 STp->in_use = 0;
1258 scsi_tape_put(STp);
1259 mutex_unlock(&st_mutex);
1260 return retval;
1261
1262 }
1263 \f
1264
1265 /* Flush the tape buffer before close */
1266 static int st_flush(struct file *filp, fl_owner_t id)
1267 {
1268 int result = 0, result2;
1269 unsigned char cmd[MAX_COMMAND_SIZE];
1270 struct st_request *SRpnt;
1271 struct scsi_tape *STp = filp->private_data;
1272 struct st_modedef *STm = &(STp->modes[STp->current_mode]);
1273 struct st_partstat *STps = &(STp->ps[STp->partition]);
1274 char *name = tape_name(STp);
1275
1276 if (file_count(filp) > 1)
1277 return 0;
1278
1279 if (STps->rw == ST_WRITING && !STp->pos_unknown) {
1280 result = st_flush_write_buffer(STp);
1281 if (result != 0 && result != (-ENOSPC))
1282 goto out;
1283 }
1284
1285 if (STp->can_partitions &&
1286 (result2 = switch_partition(STp)) < 0) {
1287 DEBC(printk(ST_DEB_MSG
1288 "%s: switch_partition at close failed.\n", name));
1289 if (result == 0)
1290 result = result2;
1291 goto out;
1292 }
1293
1294 DEBC( if (STp->nbr_requests)
1295 printk(KERN_DEBUG "%s: Number of r/w requests %d, dio used in %d, pages %d.\n",
1296 name, STp->nbr_requests, STp->nbr_dio, STp->nbr_pages));
1297
1298 if (STps->rw == ST_WRITING && !STp->pos_unknown) {
1299 struct st_cmdstatus *cmdstatp = &STp->buffer->cmdstat;
1300
1301 DEBC(printk(ST_DEB_MSG "%s: Async write waits %d, finished %d.\n",
1302 name, STp->nbr_waits, STp->nbr_finished);
1303 )
1304
1305 memset(cmd, 0, MAX_COMMAND_SIZE);
1306 cmd[0] = WRITE_FILEMARKS;
1307 cmd[4] = 1 + STp->two_fm;
1308
1309 SRpnt = st_do_scsi(NULL, STp, cmd, 0, DMA_NONE,
1310 STp->device->request_queue->rq_timeout,
1311 MAX_WRITE_RETRIES, 1);
1312 if (!SRpnt) {
1313 result = (STp->buffer)->syscall_result;
1314 goto out;
1315 }
1316
1317 if (STp->buffer->syscall_result == 0 ||
1318 (cmdstatp->have_sense && !cmdstatp->deferred &&
1319 (cmdstatp->flags & SENSE_EOM) &&
1320 (cmdstatp->sense_hdr.sense_key == NO_SENSE ||
1321 cmdstatp->sense_hdr.sense_key == RECOVERED_ERROR) &&
1322 (!cmdstatp->remainder_valid || cmdstatp->uremainder64 == 0))) {
1323 /* Write successful at EOM */
1324 st_release_request(SRpnt);
1325 SRpnt = NULL;
1326 if (STps->drv_file >= 0)
1327 STps->drv_file++;
1328 STps->drv_block = 0;
1329 if (STp->two_fm)
1330 cross_eof(STp, 0);
1331 STps->eof = ST_FM;
1332 }
1333 else { /* Write error */
1334 st_release_request(SRpnt);
1335 SRpnt = NULL;
1336 printk(KERN_ERR "%s: Error on write filemark.\n", name);
1337 if (result == 0)
1338 result = (-EIO);
1339 }
1340
1341 DEBC(printk(ST_DEB_MSG "%s: Buffer flushed, %d EOF(s) written\n",
1342 name, cmd[4]));
1343 } else if (!STp->rew_at_close) {
1344 STps = &(STp->ps[STp->partition]);
1345 if (!STm->sysv || STps->rw != ST_READING) {
1346 if (STp->can_bsr)
1347 result = flush_buffer(STp, 0);
1348 else if (STps->eof == ST_FM_HIT) {
1349 result = cross_eof(STp, 0);
1350 if (result) {
1351 if (STps->drv_file >= 0)
1352 STps->drv_file++;
1353 STps->drv_block = 0;
1354 STps->eof = ST_FM;
1355 } else
1356 STps->eof = ST_NOEOF;
1357 }
1358 } else if ((STps->eof == ST_NOEOF &&
1359 !(result = cross_eof(STp, 1))) ||
1360 STps->eof == ST_FM_HIT) {
1361 if (STps->drv_file >= 0)
1362 STps->drv_file++;
1363 STps->drv_block = 0;
1364 STps->eof = ST_FM;
1365 }
1366 }
1367
1368 out:
1369 if (STp->rew_at_close) {
1370 result2 = st_int_ioctl(STp, MTREW, 1);
1371 if (result == 0)
1372 result = result2;
1373 }
1374 return result;
1375 }
1376
1377
1378 /* Close the device and release it. BKL is not needed: this is the only thread
1379 accessing this tape. */
1380 static int st_release(struct inode *inode, struct file *filp)
1381 {
1382 int result = 0;
1383 struct scsi_tape *STp = filp->private_data;
1384
1385 if (STp->door_locked == ST_LOCKED_AUTO)
1386 do_door_lock(STp, 0);
1387
1388 normalize_buffer(STp->buffer);
1389 write_lock(&st_dev_arr_lock);
1390 STp->in_use = 0;
1391 write_unlock(&st_dev_arr_lock);
1392 scsi_tape_put(STp);
1393
1394 return result;
1395 }
1396 \f
1397 /* The checks common to both reading and writing */
1398 static ssize_t rw_checks(struct scsi_tape *STp, struct file *filp, size_t count)
1399 {
1400 ssize_t retval = 0;
1401
1402 /*
1403 * If we are in the middle of error recovery, don't let anyone
1404 * else try and use this device. Also, if error recovery fails, it
1405 * may try and take the device offline, in which case all further
1406 * access to the device is prohibited.
1407 */
1408 if (!scsi_block_when_processing_errors(STp->device)) {
1409 retval = (-ENXIO);
1410 goto out;
1411 }
1412
1413 if (STp->ready != ST_READY) {
1414 if (STp->ready == ST_NO_TAPE)
1415 retval = (-ENOMEDIUM);
1416 else
1417 retval = (-EIO);
1418 goto out;
1419 }
1420
1421 if (! STp->modes[STp->current_mode].defined) {
1422 retval = (-ENXIO);
1423 goto out;
1424 }
1425
1426
1427 /*
1428 * If there was a bus reset, block further access
1429 * to this device.
1430 */
1431 if (STp->pos_unknown) {
1432 retval = (-EIO);
1433 goto out;
1434 }
1435
1436 if (count == 0)
1437 goto out;
1438
1439 DEB(
1440 if (!STp->in_use) {
1441 printk(ST_DEB_MSG "%s: Incorrect device.\n", tape_name(STp));
1442 retval = (-EIO);
1443 goto out;
1444 } ) /* end DEB */
1445
1446 if (STp->can_partitions &&
1447 (retval = switch_partition(STp)) < 0)
1448 goto out;
1449
1450 if (STp->block_size == 0 && STp->max_block > 0 &&
1451 (count < STp->min_block || count > STp->max_block)) {
1452 retval = (-EINVAL);
1453 goto out;
1454 }
1455
1456 if (STp->do_auto_lock && STp->door_locked == ST_UNLOCKED &&
1457 !do_door_lock(STp, 1))
1458 STp->door_locked = ST_LOCKED_AUTO;
1459
1460 out:
1461 return retval;
1462 }
1463
1464
1465 static int setup_buffering(struct scsi_tape *STp, const char __user *buf,
1466 size_t count, int is_read)
1467 {
1468 int i, bufsize, retval = 0;
1469 struct st_buffer *STbp = STp->buffer;
1470
1471 if (is_read)
1472 i = STp->try_dio_now && try_rdio;
1473 else
1474 i = STp->try_dio_now && try_wdio;
1475
1476 if (i && ((unsigned long)buf & queue_dma_alignment(
1477 STp->device->request_queue)) == 0) {
1478 i = sgl_map_user_pages(STbp, STbp->use_sg, (unsigned long)buf,
1479 count, (is_read ? READ : WRITE));
1480 if (i > 0) {
1481 STbp->do_dio = i;
1482 STbp->buffer_bytes = 0; /* can be used as transfer counter */
1483 }
1484 else
1485 STbp->do_dio = 0; /* fall back to buffering with any error */
1486 STbp->sg_segs = STbp->do_dio;
1487 DEB(
1488 if (STbp->do_dio) {
1489 STp->nbr_dio++;
1490 STp->nbr_pages += STbp->do_dio;
1491 }
1492 )
1493 } else
1494 STbp->do_dio = 0;
1495 DEB( STp->nbr_requests++; )
1496
1497 if (!STbp->do_dio) {
1498 if (STp->block_size)
1499 bufsize = STp->block_size > st_fixed_buffer_size ?
1500 STp->block_size : st_fixed_buffer_size;
1501 else {
1502 bufsize = count;
1503 /* Make sure that data from previous user is not leaked even if
1504 HBA does not return correct residual */
1505 if (is_read && STp->sili && !STbp->cleared)
1506 clear_buffer(STbp);
1507 }
1508
1509 if (bufsize > STbp->buffer_size &&
1510 !enlarge_buffer(STbp, bufsize, STp->restr_dma)) {
1511 printk(KERN_WARNING "%s: Can't allocate %d byte tape buffer.\n",
1512 tape_name(STp), bufsize);
1513 retval = (-EOVERFLOW);
1514 goto out;
1515 }
1516 if (STp->block_size)
1517 STbp->buffer_blocks = bufsize / STp->block_size;
1518 }
1519
1520 out:
1521 return retval;
1522 }
1523
1524
1525 /* Can be called more than once after each setup_buffer() */
1526 static void release_buffering(struct scsi_tape *STp, int is_read)
1527 {
1528 struct st_buffer *STbp;
1529
1530 STbp = STp->buffer;
1531 if (STbp->do_dio) {
1532 sgl_unmap_user_pages(STbp, STbp->do_dio, is_read);
1533 STbp->do_dio = 0;
1534 STbp->sg_segs = 0;
1535 }
1536 }
1537
1538
1539 /* Write command */
1540 static ssize_t
1541 st_write(struct file *filp, const char __user *buf, size_t count, loff_t * ppos)
1542 {
1543 ssize_t total;
1544 ssize_t i, do_count, blks, transfer;
1545 ssize_t retval;
1546 int undone, retry_eot = 0, scode;
1547 int async_write;
1548 unsigned char cmd[MAX_COMMAND_SIZE];
1549 const char __user *b_point;
1550 struct st_request *SRpnt = NULL;
1551 struct scsi_tape *STp = filp->private_data;
1552 struct st_modedef *STm;
1553 struct st_partstat *STps;
1554 struct st_buffer *STbp;
1555 char *name = tape_name(STp);
1556
1557 if (mutex_lock_interruptible(&STp->lock))
1558 return -ERESTARTSYS;
1559
1560 retval = rw_checks(STp, filp, count);
1561 if (retval || count == 0)
1562 goto out;
1563
1564 /* Write must be integral number of blocks */
1565 if (STp->block_size != 0 && (count % STp->block_size) != 0) {
1566 printk(KERN_WARNING "%s: Write not multiple of tape block size.\n",
1567 name);
1568 retval = (-EINVAL);
1569 goto out;
1570 }
1571
1572 STm = &(STp->modes[STp->current_mode]);
1573 STps = &(STp->ps[STp->partition]);
1574
1575 if (STp->write_prot) {
1576 retval = (-EACCES);
1577 goto out;
1578 }
1579
1580
1581 if (STps->rw == ST_READING) {
1582 retval = flush_buffer(STp, 0);
1583 if (retval)
1584 goto out;
1585 STps->rw = ST_WRITING;
1586 } else if (STps->rw != ST_WRITING &&
1587 STps->drv_file == 0 && STps->drv_block == 0) {
1588 if ((retval = set_mode_densblk(STp, STm)) < 0)
1589 goto out;
1590 if (STm->default_compression != ST_DONT_TOUCH &&
1591 !(STp->compression_changed)) {
1592 if (st_compression(STp, (STm->default_compression == ST_YES))) {
1593 printk(KERN_WARNING "%s: Can't set default compression.\n",
1594 name);
1595 if (modes_defined) {
1596 retval = (-EINVAL);
1597 goto out;
1598 }
1599 }
1600 }
1601 }
1602
1603 STbp = STp->buffer;
1604 i = write_behind_check(STp);
1605 if (i) {
1606 if (i == -ENOSPC)
1607 STps->eof = ST_EOM_OK;
1608 else
1609 STps->eof = ST_EOM_ERROR;
1610 }
1611
1612 if (STps->eof == ST_EOM_OK) {
1613 STps->eof = ST_EOD_1; /* allow next write */
1614 retval = (-ENOSPC);
1615 goto out;
1616 }
1617 else if (STps->eof == ST_EOM_ERROR) {
1618 retval = (-EIO);
1619 goto out;
1620 }
1621
1622 /* Check the buffer readability in cases where copy_user might catch
1623 the problems after some tape movement. */
1624 if (STp->block_size != 0 &&
1625 !STbp->do_dio &&
1626 (copy_from_user(&i, buf, 1) != 0 ||
1627 copy_from_user(&i, buf + count - 1, 1) != 0)) {
1628 retval = (-EFAULT);
1629 goto out;
1630 }
1631
1632 retval = setup_buffering(STp, buf, count, 0);
1633 if (retval)
1634 goto out;
1635
1636 total = count;
1637
1638 memset(cmd, 0, MAX_COMMAND_SIZE);
1639 cmd[0] = WRITE_6;
1640 cmd[1] = (STp->block_size != 0);
1641
1642 STps->rw = ST_WRITING;
1643
1644 b_point = buf;
1645 while (count > 0 && !retry_eot) {
1646
1647 if (STbp->do_dio) {
1648 do_count = count;
1649 }
1650 else {
1651 if (STp->block_size == 0)
1652 do_count = count;
1653 else {
1654 do_count = STbp->buffer_blocks * STp->block_size -
1655 STbp->buffer_bytes;
1656 if (do_count > count)
1657 do_count = count;
1658 }
1659
1660 i = append_to_buffer(b_point, STbp, do_count);
1661 if (i) {
1662 retval = i;
1663 goto out;
1664 }
1665 }
1666 count -= do_count;
1667 b_point += do_count;
1668
1669 async_write = STp->block_size == 0 && !STbp->do_dio &&
1670 STm->do_async_writes && STps->eof < ST_EOM_OK;
1671
1672 if (STp->block_size != 0 && STm->do_buffer_writes &&
1673 !(STp->try_dio_now && try_wdio) && STps->eof < ST_EOM_OK &&
1674 STbp->buffer_bytes < STbp->buffer_size) {
1675 STp->dirty = 1;
1676 /* Don't write a buffer that is not full enough. */
1677 if (!async_write && count == 0)
1678 break;
1679 }
1680
1681 retry_write:
1682 if (STp->block_size == 0)
1683 blks = transfer = do_count;
1684 else {
1685 if (!STbp->do_dio)
1686 blks = STbp->buffer_bytes;
1687 else
1688 blks = do_count;
1689 blks /= STp->block_size;
1690 transfer = blks * STp->block_size;
1691 }
1692 cmd[2] = blks >> 16;
1693 cmd[3] = blks >> 8;
1694 cmd[4] = blks;
1695
1696 SRpnt = st_do_scsi(SRpnt, STp, cmd, transfer, DMA_TO_DEVICE,
1697 STp->device->request_queue->rq_timeout,
1698 MAX_WRITE_RETRIES, !async_write);
1699 if (!SRpnt) {
1700 retval = STbp->syscall_result;
1701 goto out;
1702 }
1703 if (async_write && !STbp->syscall_result) {
1704 STbp->writing = transfer;
1705 STp->dirty = !(STbp->writing ==
1706 STbp->buffer_bytes);
1707 SRpnt = NULL; /* Prevent releasing this request! */
1708 DEB( STp->write_pending = 1; )
1709 break;
1710 }
1711
1712 if (STbp->syscall_result != 0) {
1713 struct st_cmdstatus *cmdstatp = &STp->buffer->cmdstat;
1714
1715 DEBC(printk(ST_DEB_MSG "%s: Error on write:\n", name));
1716 if (cmdstatp->have_sense && (cmdstatp->flags & SENSE_EOM)) {
1717 scode = cmdstatp->sense_hdr.sense_key;
1718 if (cmdstatp->remainder_valid)
1719 undone = (int)cmdstatp->uremainder64;
1720 else if (STp->block_size == 0 &&
1721 scode == VOLUME_OVERFLOW)
1722 undone = transfer;
1723 else
1724 undone = 0;
1725 if (STp->block_size != 0)
1726 undone *= STp->block_size;
1727 if (undone <= do_count) {
1728 /* Only data from this write is not written */
1729 count += undone;
1730 b_point -= undone;
1731 do_count -= undone;
1732 if (STp->block_size)
1733 blks = (transfer - undone) / STp->block_size;
1734 STps->eof = ST_EOM_OK;
1735 /* Continue in fixed block mode if all written
1736 in this request but still something left to write
1737 (retval left to zero)
1738 */
1739 if (STp->block_size == 0 ||
1740 undone > 0 || count == 0)
1741 retval = (-ENOSPC); /* EOM within current request */
1742 DEBC(printk(ST_DEB_MSG
1743 "%s: EOM with %d bytes unwritten.\n",
1744 name, (int)count));
1745 } else {
1746 /* EOT within data buffered earlier (possible only
1747 in fixed block mode without direct i/o) */
1748 if (!retry_eot && !cmdstatp->deferred &&
1749 (scode == NO_SENSE || scode == RECOVERED_ERROR)) {
1750 move_buffer_data(STp->buffer, transfer - undone);
1751 retry_eot = 1;
1752 if (STps->drv_block >= 0) {
1753 STps->drv_block += (transfer - undone) /
1754 STp->block_size;
1755 }
1756 STps->eof = ST_EOM_OK;
1757 DEBC(printk(ST_DEB_MSG
1758 "%s: Retry write of %d bytes at EOM.\n",
1759 name, STp->buffer->buffer_bytes));
1760 goto retry_write;
1761 }
1762 else {
1763 /* Either error within data buffered by driver or
1764 failed retry */
1765 count -= do_count;
1766 blks = do_count = 0;
1767 STps->eof = ST_EOM_ERROR;
1768 STps->drv_block = (-1); /* Too cautious? */
1769 retval = (-EIO); /* EOM for old data */
1770 DEBC(printk(ST_DEB_MSG
1771 "%s: EOM with lost data.\n",
1772 name));
1773 }
1774 }
1775 } else {
1776 count += do_count;
1777 STps->drv_block = (-1); /* Too cautious? */
1778 retval = STbp->syscall_result;
1779 }
1780
1781 }
1782
1783 if (STps->drv_block >= 0) {
1784 if (STp->block_size == 0)
1785 STps->drv_block += (do_count > 0);
1786 else
1787 STps->drv_block += blks;
1788 }
1789
1790 STbp->buffer_bytes = 0;
1791 STp->dirty = 0;
1792
1793 if (retval || retry_eot) {
1794 if (count < total)
1795 retval = total - count;
1796 goto out;
1797 }
1798 }
1799
1800 if (STps->eof == ST_EOD_1)
1801 STps->eof = ST_EOM_OK;
1802 else if (STps->eof != ST_EOM_OK)
1803 STps->eof = ST_NOEOF;
1804 retval = total - count;
1805
1806 out:
1807 if (SRpnt != NULL)
1808 st_release_request(SRpnt);
1809 release_buffering(STp, 0);
1810 mutex_unlock(&STp->lock);
1811
1812 return retval;
1813 }
1814 \f
1815 /* Read data from the tape. Returns zero in the normal case, one if the
1816 eof status has changed, and the negative error code in case of a
1817 fatal error. Otherwise updates the buffer and the eof state.
1818
1819 Does release user buffer mapping if it is set.
1820 */
1821 static long read_tape(struct scsi_tape *STp, long count,
1822 struct st_request ** aSRpnt)
1823 {
1824 int transfer, blks, bytes;
1825 unsigned char cmd[MAX_COMMAND_SIZE];
1826 struct st_request *SRpnt;
1827 struct st_modedef *STm;
1828 struct st_partstat *STps;
1829 struct st_buffer *STbp;
1830 int retval = 0;
1831 char *name = tape_name(STp);
1832
1833 if (count == 0)
1834 return 0;
1835
1836 STm = &(STp->modes[STp->current_mode]);
1837 STps = &(STp->ps[STp->partition]);
1838 if (STps->eof == ST_FM_HIT)
1839 return 1;
1840 STbp = STp->buffer;
1841
1842 if (STp->block_size == 0)
1843 blks = bytes = count;
1844 else {
1845 if (!(STp->try_dio_now && try_rdio) && STm->do_read_ahead) {
1846 blks = (STp->buffer)->buffer_blocks;
1847 bytes = blks * STp->block_size;
1848 } else {
1849 bytes = count;
1850 if (!STbp->do_dio && bytes > (STp->buffer)->buffer_size)
1851 bytes = (STp->buffer)->buffer_size;
1852 blks = bytes / STp->block_size;
1853 bytes = blks * STp->block_size;
1854 }
1855 }
1856
1857 memset(cmd, 0, MAX_COMMAND_SIZE);
1858 cmd[0] = READ_6;
1859 cmd[1] = (STp->block_size != 0);
1860 if (!cmd[1] && STp->sili)
1861 cmd[1] |= 2;
1862 cmd[2] = blks >> 16;
1863 cmd[3] = blks >> 8;
1864 cmd[4] = blks;
1865
1866 SRpnt = *aSRpnt;
1867 SRpnt = st_do_scsi(SRpnt, STp, cmd, bytes, DMA_FROM_DEVICE,
1868 STp->device->request_queue->rq_timeout,
1869 MAX_RETRIES, 1);
1870 release_buffering(STp, 1);
1871 *aSRpnt = SRpnt;
1872 if (!SRpnt)
1873 return STbp->syscall_result;
1874
1875 STbp->read_pointer = 0;
1876 STps->at_sm = 0;
1877
1878 /* Something to check */
1879 if (STbp->syscall_result) {
1880 struct st_cmdstatus *cmdstatp = &STp->buffer->cmdstat;
1881
1882 retval = 1;
1883 DEBC(printk(ST_DEB_MSG "%s: Sense: %2x %2x %2x %2x %2x %2x %2x %2x\n",
1884 name,
1885 SRpnt->sense[0], SRpnt->sense[1],
1886 SRpnt->sense[2], SRpnt->sense[3],
1887 SRpnt->sense[4], SRpnt->sense[5],
1888 SRpnt->sense[6], SRpnt->sense[7]));
1889 if (cmdstatp->have_sense) {
1890
1891 if (cmdstatp->sense_hdr.sense_key == BLANK_CHECK)
1892 cmdstatp->flags &= 0xcf; /* No need for EOM in this case */
1893
1894 if (cmdstatp->flags != 0) { /* EOF, EOM, or ILI */
1895 /* Compute the residual count */
1896 if (cmdstatp->remainder_valid)
1897 transfer = (int)cmdstatp->uremainder64;
1898 else
1899 transfer = 0;
1900 if (STp->block_size == 0 &&
1901 cmdstatp->sense_hdr.sense_key == MEDIUM_ERROR)
1902 transfer = bytes;
1903
1904 if (cmdstatp->flags & SENSE_ILI) { /* ILI */
1905 if (STp->block_size == 0) {
1906 if (transfer <= 0) {
1907 if (transfer < 0)
1908 printk(KERN_NOTICE
1909 "%s: Failed to read %d byte block with %d byte transfer.\n",
1910 name, bytes - transfer, bytes);
1911 if (STps->drv_block >= 0)
1912 STps->drv_block += 1;
1913 STbp->buffer_bytes = 0;
1914 return (-ENOMEM);
1915 }
1916 STbp->buffer_bytes = bytes - transfer;
1917 } else {
1918 st_release_request(SRpnt);
1919 SRpnt = *aSRpnt = NULL;
1920 if (transfer == blks) { /* We did not get anything, error */
1921 printk(KERN_NOTICE "%s: Incorrect block size.\n", name);
1922 if (STps->drv_block >= 0)
1923 STps->drv_block += blks - transfer + 1;
1924 st_int_ioctl(STp, MTBSR, 1);
1925 return (-EIO);
1926 }
1927 /* We have some data, deliver it */
1928 STbp->buffer_bytes = (blks - transfer) *
1929 STp->block_size;
1930 DEBC(printk(ST_DEB_MSG
1931 "%s: ILI but enough data received %ld %d.\n",
1932 name, count, STbp->buffer_bytes));
1933 if (STps->drv_block >= 0)
1934 STps->drv_block += 1;
1935 if (st_int_ioctl(STp, MTBSR, 1))
1936 return (-EIO);
1937 }
1938 } else if (cmdstatp->flags & SENSE_FMK) { /* FM overrides EOM */
1939 if (STps->eof != ST_FM_HIT)
1940 STps->eof = ST_FM_HIT;
1941 else
1942 STps->eof = ST_EOD_2;
1943 if (STp->block_size == 0)
1944 STbp->buffer_bytes = 0;
1945 else
1946 STbp->buffer_bytes =
1947 bytes - transfer * STp->block_size;
1948 DEBC(printk(ST_DEB_MSG
1949 "%s: EOF detected (%d bytes read).\n",
1950 name, STbp->buffer_bytes));
1951 } else if (cmdstatp->flags & SENSE_EOM) {
1952 if (STps->eof == ST_FM)
1953 STps->eof = ST_EOD_1;
1954 else
1955 STps->eof = ST_EOM_OK;
1956 if (STp->block_size == 0)
1957 STbp->buffer_bytes = bytes - transfer;
1958 else
1959 STbp->buffer_bytes =
1960 bytes - transfer * STp->block_size;
1961
1962 DEBC(printk(ST_DEB_MSG "%s: EOM detected (%d bytes read).\n",
1963 name, STbp->buffer_bytes));
1964 }
1965 }
1966 /* end of EOF, EOM, ILI test */
1967 else { /* nonzero sense key */
1968 DEBC(printk(ST_DEB_MSG
1969 "%s: Tape error while reading.\n", name));
1970 STps->drv_block = (-1);
1971 if (STps->eof == ST_FM &&
1972 cmdstatp->sense_hdr.sense_key == BLANK_CHECK) {
1973 DEBC(printk(ST_DEB_MSG
1974 "%s: Zero returned for first BLANK CHECK after EOF.\n",
1975 name));
1976 STps->eof = ST_EOD_2; /* First BLANK_CHECK after FM */
1977 } else /* Some other extended sense code */
1978 retval = (-EIO);
1979 }
1980
1981 if (STbp->buffer_bytes < 0) /* Caused by bogus sense data */
1982 STbp->buffer_bytes = 0;
1983 }
1984 /* End of extended sense test */
1985 else { /* Non-extended sense */
1986 retval = STbp->syscall_result;
1987 }
1988
1989 }
1990 /* End of error handling */
1991 else { /* Read successful */
1992 STbp->buffer_bytes = bytes;
1993 if (STp->sili) /* In fixed block mode residual is always zero here */
1994 STbp->buffer_bytes -= STp->buffer->cmdstat.residual;
1995 }
1996
1997 if (STps->drv_block >= 0) {
1998 if (STp->block_size == 0)
1999 STps->drv_block++;
2000 else
2001 STps->drv_block += STbp->buffer_bytes / STp->block_size;
2002 }
2003 return retval;
2004 }
2005 \f
2006
2007 /* Read command */
2008 static ssize_t
2009 st_read(struct file *filp, char __user *buf, size_t count, loff_t * ppos)
2010 {
2011 ssize_t total;
2012 ssize_t retval = 0;
2013 ssize_t i, transfer;
2014 int special, do_dio = 0;
2015 struct st_request *SRpnt = NULL;
2016 struct scsi_tape *STp = filp->private_data;
2017 struct st_modedef *STm;
2018 struct st_partstat *STps;
2019 struct st_buffer *STbp = STp->buffer;
2020 DEB( char *name = tape_name(STp); )
2021
2022 if (mutex_lock_interruptible(&STp->lock))
2023 return -ERESTARTSYS;
2024
2025 retval = rw_checks(STp, filp, count);
2026 if (retval || count == 0)
2027 goto out;
2028
2029 STm = &(STp->modes[STp->current_mode]);
2030 if (STp->block_size != 0 && (count % STp->block_size) != 0) {
2031 if (!STm->do_read_ahead) {
2032 retval = (-EINVAL); /* Read must be integral number of blocks */
2033 goto out;
2034 }
2035 STp->try_dio_now = 0; /* Direct i/o can't handle split blocks */
2036 }
2037
2038 STps = &(STp->ps[STp->partition]);
2039 if (STps->rw == ST_WRITING) {
2040 retval = flush_buffer(STp, 0);
2041 if (retval)
2042 goto out;
2043 STps->rw = ST_READING;
2044 }
2045 DEB(
2046 if (debugging && STps->eof != ST_NOEOF)
2047 printk(ST_DEB_MSG "%s: EOF/EOM flag up (%d). Bytes %d\n", name,
2048 STps->eof, STbp->buffer_bytes);
2049 ) /* end DEB */
2050
2051 retval = setup_buffering(STp, buf, count, 1);
2052 if (retval)
2053 goto out;
2054 do_dio = STbp->do_dio;
2055
2056 if (STbp->buffer_bytes == 0 &&
2057 STps->eof >= ST_EOD_1) {
2058 if (STps->eof < ST_EOD) {
2059 STps->eof += 1;
2060 retval = 0;
2061 goto out;
2062 }
2063 retval = (-EIO); /* EOM or Blank Check */
2064 goto out;
2065 }
2066
2067 if (do_dio) {
2068 /* Check the buffer writability before any tape movement. Don't alter
2069 buffer data. */
2070 if (copy_from_user(&i, buf, 1) != 0 ||
2071 copy_to_user(buf, &i, 1) != 0 ||
2072 copy_from_user(&i, buf + count - 1, 1) != 0 ||
2073 copy_to_user(buf + count - 1, &i, 1) != 0) {
2074 retval = (-EFAULT);
2075 goto out;
2076 }
2077 }
2078
2079 STps->rw = ST_READING;
2080
2081
2082 /* Loop until enough data in buffer or a special condition found */
2083 for (total = 0, special = 0; total < count && !special;) {
2084
2085 /* Get new data if the buffer is empty */
2086 if (STbp->buffer_bytes == 0) {
2087 special = read_tape(STp, count - total, &SRpnt);
2088 if (special < 0) { /* No need to continue read */
2089 retval = special;
2090 goto out;
2091 }
2092 }
2093
2094 /* Move the data from driver buffer to user buffer */
2095 if (STbp->buffer_bytes > 0) {
2096 DEB(
2097 if (debugging && STps->eof != ST_NOEOF)
2098 printk(ST_DEB_MSG
2099 "%s: EOF up (%d). Left %d, needed %d.\n", name,
2100 STps->eof, STbp->buffer_bytes,
2101 (int)(count - total));
2102 ) /* end DEB */
2103 transfer = STbp->buffer_bytes < count - total ?
2104 STbp->buffer_bytes : count - total;
2105 if (!do_dio) {
2106 i = from_buffer(STbp, buf, transfer);
2107 if (i) {
2108 retval = i;
2109 goto out;
2110 }
2111 }
2112 buf += transfer;
2113 total += transfer;
2114 }
2115
2116 if (STp->block_size == 0)
2117 break; /* Read only one variable length block */
2118
2119 } /* for (total = 0, special = 0;
2120 total < count && !special; ) */
2121
2122 /* Change the eof state if no data from tape or buffer */
2123 if (total == 0) {
2124 if (STps->eof == ST_FM_HIT) {
2125 STps->eof = ST_FM;
2126 STps->drv_block = 0;
2127 if (STps->drv_file >= 0)
2128 STps->drv_file++;
2129 } else if (STps->eof == ST_EOD_1) {
2130 STps->eof = ST_EOD_2;
2131 STps->drv_block = 0;
2132 if (STps->drv_file >= 0)
2133 STps->drv_file++;
2134 } else if (STps->eof == ST_EOD_2)
2135 STps->eof = ST_EOD;
2136 } else if (STps->eof == ST_FM)
2137 STps->eof = ST_NOEOF;
2138 retval = total;
2139
2140 out:
2141 if (SRpnt != NULL) {
2142 st_release_request(SRpnt);
2143 SRpnt = NULL;
2144 }
2145 if (do_dio) {
2146 release_buffering(STp, 1);
2147 STbp->buffer_bytes = 0;
2148 }
2149 mutex_unlock(&STp->lock);
2150
2151 return retval;
2152 }
2153 \f
2154
2155
2156 DEB(
2157 /* Set the driver options */
2158 static void st_log_options(struct scsi_tape * STp, struct st_modedef * STm, char *name)
2159 {
2160 if (debugging) {
2161 printk(KERN_INFO
2162 "%s: Mode %d options: buffer writes: %d, async writes: %d, read ahead: %d\n",
2163 name, STp->current_mode, STm->do_buffer_writes, STm->do_async_writes,
2164 STm->do_read_ahead);
2165 printk(KERN_INFO
2166 "%s: can bsr: %d, two FMs: %d, fast mteom: %d, auto lock: %d,\n",
2167 name, STp->can_bsr, STp->two_fm, STp->fast_mteom, STp->do_auto_lock);
2168 printk(KERN_INFO
2169 "%s: defs for wr: %d, no block limits: %d, partitions: %d, s2 log: %d\n",
2170 name, STm->defaults_for_writes, STp->omit_blklims, STp->can_partitions,
2171 STp->scsi2_logical);
2172 printk(KERN_INFO
2173 "%s: sysv: %d nowait: %d sili: %d\n", name, STm->sysv, STp->immediate,
2174 STp->sili);
2175 printk(KERN_INFO "%s: debugging: %d\n",
2176 name, debugging);
2177 }
2178 }
2179 )
2180
2181
2182 static int st_set_options(struct scsi_tape *STp, long options)
2183 {
2184 int value;
2185 long code;
2186 struct st_modedef *STm;
2187 char *name = tape_name(STp);
2188 struct cdev *cd0, *cd1;
2189
2190 STm = &(STp->modes[STp->current_mode]);
2191 if (!STm->defined) {
2192 cd0 = STm->cdevs[0]; cd1 = STm->cdevs[1];
2193 memcpy(STm, &(STp->modes[0]), sizeof(struct st_modedef));
2194 STm->cdevs[0] = cd0; STm->cdevs[1] = cd1;
2195 modes_defined = 1;
2196 DEBC(printk(ST_DEB_MSG
2197 "%s: Initialized mode %d definition from mode 0\n",
2198 name, STp->current_mode));
2199 }
2200
2201 code = options & MT_ST_OPTIONS;
2202 if (code == MT_ST_BOOLEANS) {
2203 STm->do_buffer_writes = (options & MT_ST_BUFFER_WRITES) != 0;
2204 STm->do_async_writes = (options & MT_ST_ASYNC_WRITES) != 0;
2205 STm->defaults_for_writes = (options & MT_ST_DEF_WRITES) != 0;
2206 STm->do_read_ahead = (options & MT_ST_READ_AHEAD) != 0;
2207 STp->two_fm = (options & MT_ST_TWO_FM) != 0;
2208 STp->fast_mteom = (options & MT_ST_FAST_MTEOM) != 0;
2209 STp->do_auto_lock = (options & MT_ST_AUTO_LOCK) != 0;
2210 STp->can_bsr = (options & MT_ST_CAN_BSR) != 0;
2211 STp->omit_blklims = (options & MT_ST_NO_BLKLIMS) != 0;
2212 if ((STp->device)->scsi_level >= SCSI_2)
2213 STp->can_partitions = (options & MT_ST_CAN_PARTITIONS) != 0;
2214 STp->scsi2_logical = (options & MT_ST_SCSI2LOGICAL) != 0;
2215 STp->immediate = (options & MT_ST_NOWAIT) != 0;
2216 STm->sysv = (options & MT_ST_SYSV) != 0;
2217 STp->sili = (options & MT_ST_SILI) != 0;
2218 DEB( debugging = (options & MT_ST_DEBUGGING) != 0;
2219 st_log_options(STp, STm, name); )
2220 } else if (code == MT_ST_SETBOOLEANS || code == MT_ST_CLEARBOOLEANS) {
2221 value = (code == MT_ST_SETBOOLEANS);
2222 if ((options & MT_ST_BUFFER_WRITES) != 0)
2223 STm->do_buffer_writes = value;
2224 if ((options & MT_ST_ASYNC_WRITES) != 0)
2225 STm->do_async_writes = value;
2226 if ((options & MT_ST_DEF_WRITES) != 0)
2227 STm->defaults_for_writes = value;
2228 if ((options & MT_ST_READ_AHEAD) != 0)
2229 STm->do_read_ahead = value;
2230 if ((options & MT_ST_TWO_FM) != 0)
2231 STp->two_fm = value;
2232 if ((options & MT_ST_FAST_MTEOM) != 0)
2233 STp->fast_mteom = value;
2234 if ((options & MT_ST_AUTO_LOCK) != 0)
2235 STp->do_auto_lock = value;
2236 if ((options & MT_ST_CAN_BSR) != 0)
2237 STp->can_bsr = value;
2238 if ((options & MT_ST_NO_BLKLIMS) != 0)
2239 STp->omit_blklims = value;
2240 if ((STp->device)->scsi_level >= SCSI_2 &&
2241 (options & MT_ST_CAN_PARTITIONS) != 0)
2242 STp->can_partitions = value;
2243 if ((options & MT_ST_SCSI2LOGICAL) != 0)
2244 STp->scsi2_logical = value;
2245 if ((options & MT_ST_NOWAIT) != 0)
2246 STp->immediate = value;
2247 if ((options & MT_ST_SYSV) != 0)
2248 STm->sysv = value;
2249 if ((options & MT_ST_SILI) != 0)
2250 STp->sili = value;
2251 DEB(
2252 if ((options & MT_ST_DEBUGGING) != 0)
2253 debugging = value;
2254 st_log_options(STp, STm, name); )
2255 } else if (code == MT_ST_WRITE_THRESHOLD) {
2256 /* Retained for compatibility */
2257 } else if (code == MT_ST_DEF_BLKSIZE) {
2258 value = (options & ~MT_ST_OPTIONS);
2259 if (value == ~MT_ST_OPTIONS) {
2260 STm->default_blksize = (-1);
2261 DEBC( printk(KERN_INFO "%s: Default block size disabled.\n", name));
2262 } else {
2263 STm->default_blksize = value;
2264 DEBC( printk(KERN_INFO "%s: Default block size set to %d bytes.\n",
2265 name, STm->default_blksize));
2266 if (STp->ready == ST_READY) {
2267 STp->blksize_changed = 0;
2268 set_mode_densblk(STp, STm);
2269 }
2270 }
2271 } else if (code == MT_ST_TIMEOUTS) {
2272 value = (options & ~MT_ST_OPTIONS);
2273 if ((value & MT_ST_SET_LONG_TIMEOUT) != 0) {
2274 STp->long_timeout = (value & ~MT_ST_SET_LONG_TIMEOUT) * HZ;
2275 DEBC( printk(KERN_INFO "%s: Long timeout set to %d seconds.\n", name,
2276 (value & ~MT_ST_SET_LONG_TIMEOUT)));
2277 } else {
2278 blk_queue_rq_timeout(STp->device->request_queue,
2279 value * HZ);
2280 DEBC( printk(KERN_INFO "%s: Normal timeout set to %d seconds.\n",
2281 name, value) );
2282 }
2283 } else if (code == MT_ST_SET_CLN) {
2284 value = (options & ~MT_ST_OPTIONS) & 0xff;
2285 if (value != 0 &&
2286 (value < EXTENDED_SENSE_START ||
2287 value >= SCSI_SENSE_BUFFERSIZE))
2288 return (-EINVAL);
2289 STp->cln_mode = value;
2290 STp->cln_sense_mask = (options >> 8) & 0xff;
2291 STp->cln_sense_value = (options >> 16) & 0xff;
2292 printk(KERN_INFO
2293 "%s: Cleaning request mode %d, mask %02x, value %02x\n",
2294 name, value, STp->cln_sense_mask, STp->cln_sense_value);
2295 } else if (code == MT_ST_DEF_OPTIONS) {
2296 code = (options & ~MT_ST_CLEAR_DEFAULT);
2297 value = (options & MT_ST_CLEAR_DEFAULT);
2298 if (code == MT_ST_DEF_DENSITY) {
2299 if (value == MT_ST_CLEAR_DEFAULT) {
2300 STm->default_density = (-1);
2301 DEBC( printk(KERN_INFO "%s: Density default disabled.\n",
2302 name));
2303 } else {
2304 STm->default_density = value & 0xff;
2305 DEBC( printk(KERN_INFO "%s: Density default set to %x\n",
2306 name, STm->default_density));
2307 if (STp->ready == ST_READY) {
2308 STp->density_changed = 0;
2309 set_mode_densblk(STp, STm);
2310 }
2311 }
2312 } else if (code == MT_ST_DEF_DRVBUFFER) {
2313 if (value == MT_ST_CLEAR_DEFAULT) {
2314 STp->default_drvbuffer = 0xff;
2315 DEBC( printk(KERN_INFO
2316 "%s: Drive buffer default disabled.\n", name));
2317 } else {
2318 STp->default_drvbuffer = value & 7;
2319 DEBC( printk(KERN_INFO
2320 "%s: Drive buffer default set to %x\n",
2321 name, STp->default_drvbuffer));
2322 if (STp->ready == ST_READY)
2323 st_int_ioctl(STp, MTSETDRVBUFFER, STp->default_drvbuffer);
2324 }
2325 } else if (code == MT_ST_DEF_COMPRESSION) {
2326 if (value == MT_ST_CLEAR_DEFAULT) {
2327 STm->default_compression = ST_DONT_TOUCH;
2328 DEBC( printk(KERN_INFO
2329 "%s: Compression default disabled.\n", name));
2330 } else {
2331 if ((value & 0xff00) != 0) {
2332 STp->c_algo = (value & 0xff00) >> 8;
2333 DEBC( printk(KERN_INFO "%s: Compression algorithm set to 0x%x.\n",
2334 name, STp->c_algo));
2335 }
2336 if ((value & 0xff) != 0xff) {
2337 STm->default_compression = (value & 1 ? ST_YES : ST_NO);
2338 DEBC( printk(KERN_INFO "%s: Compression default set to %x\n",
2339 name, (value & 1)));
2340 if (STp->ready == ST_READY) {
2341 STp->compression_changed = 0;
2342 st_compression(STp, (STm->default_compression == ST_YES));
2343 }
2344 }
2345 }
2346 }
2347 } else
2348 return (-EIO);
2349
2350 return 0;
2351 }
2352 \f
2353 #define MODE_HEADER_LENGTH 4
2354
2355 /* Mode header and page byte offsets */
2356 #define MH_OFF_DATA_LENGTH 0
2357 #define MH_OFF_MEDIUM_TYPE 1
2358 #define MH_OFF_DEV_SPECIFIC 2
2359 #define MH_OFF_BDESCS_LENGTH 3
2360 #define MP_OFF_PAGE_NBR 0
2361 #define MP_OFF_PAGE_LENGTH 1
2362
2363 /* Mode header and page bit masks */
2364 #define MH_BIT_WP 0x80
2365 #define MP_MSK_PAGE_NBR 0x3f
2366
2367 /* Don't return block descriptors */
2368 #define MODE_SENSE_OMIT_BDESCS 0x08
2369
2370 #define MODE_SELECT_PAGE_FORMAT 0x10
2371
2372 /* Read a mode page into the tape buffer. The block descriptors are included
2373 if incl_block_descs is true. The page control is ored to the page number
2374 parameter, if necessary. */
2375 static int read_mode_page(struct scsi_tape *STp, int page, int omit_block_descs)
2376 {
2377 unsigned char cmd[MAX_COMMAND_SIZE];
2378 struct st_request *SRpnt;
2379
2380 memset(cmd, 0, MAX_COMMAND_SIZE);
2381 cmd[0] = MODE_SENSE;
2382 if (omit_block_descs)
2383 cmd[1] = MODE_SENSE_OMIT_BDESCS;
2384 cmd[2] = page;
2385 cmd[4] = 255;
2386
2387 SRpnt = st_do_scsi(NULL, STp, cmd, cmd[4], DMA_FROM_DEVICE,
2388 STp->device->request_queue->rq_timeout, 0, 1);
2389 if (SRpnt == NULL)
2390 return (STp->buffer)->syscall_result;
2391
2392 st_release_request(SRpnt);
2393
2394 return STp->buffer->syscall_result;
2395 }
2396
2397
2398 /* Send the mode page in the tape buffer to the drive. Assumes that the mode data
2399 in the buffer is correctly formatted. The long timeout is used if slow is non-zero. */
2400 static int write_mode_page(struct scsi_tape *STp, int page, int slow)
2401 {
2402 int pgo;
2403 unsigned char cmd[MAX_COMMAND_SIZE];
2404 struct st_request *SRpnt;
2405 int timeout;
2406
2407 memset(cmd, 0, MAX_COMMAND_SIZE);
2408 cmd[0] = MODE_SELECT;
2409 cmd[1] = MODE_SELECT_PAGE_FORMAT;
2410 pgo = MODE_HEADER_LENGTH + (STp->buffer)->b_data[MH_OFF_BDESCS_LENGTH];
2411 cmd[4] = pgo + (STp->buffer)->b_data[pgo + MP_OFF_PAGE_LENGTH] + 2;
2412
2413 /* Clear reserved fields */
2414 (STp->buffer)->b_data[MH_OFF_DATA_LENGTH] = 0;
2415 (STp->buffer)->b_data[MH_OFF_MEDIUM_TYPE] = 0;
2416 (STp->buffer)->b_data[MH_OFF_DEV_SPECIFIC] &= ~MH_BIT_WP;
2417 (STp->buffer)->b_data[pgo + MP_OFF_PAGE_NBR] &= MP_MSK_PAGE_NBR;
2418
2419 timeout = slow ?
2420 STp->long_timeout : STp->device->request_queue->rq_timeout;
2421 SRpnt = st_do_scsi(NULL, STp, cmd, cmd[4], DMA_TO_DEVICE,
2422 timeout, 0, 1);
2423 if (SRpnt == NULL)
2424 return (STp->buffer)->syscall_result;
2425
2426 st_release_request(SRpnt);
2427
2428 return STp->buffer->syscall_result;
2429 }
2430
2431
2432 #define COMPRESSION_PAGE 0x0f
2433 #define COMPRESSION_PAGE_LENGTH 16
2434
2435 #define CP_OFF_DCE_DCC 2
2436 #define CP_OFF_C_ALGO 7
2437
2438 #define DCE_MASK 0x80
2439 #define DCC_MASK 0x40
2440 #define RED_MASK 0x60
2441
2442
2443 /* Control the compression with mode page 15. Algorithm not changed if zero.
2444
2445 The block descriptors are read and written because Sony SDT-7000 does not
2446 work without this (suggestion from Michael Schaefer <Michael.Schaefer@dlr.de>).
2447 Including block descriptors should not cause any harm to other drives. */
2448
2449 static int st_compression(struct scsi_tape * STp, int state)
2450 {
2451 int retval;
2452 int mpoffs; /* Offset to mode page start */
2453 unsigned char *b_data = (STp->buffer)->b_data;
2454 DEB( char *name = tape_name(STp); )
2455
2456 if (STp->ready != ST_READY)
2457 return (-EIO);
2458
2459 /* Read the current page contents */
2460 retval = read_mode_page(STp, COMPRESSION_PAGE, 0);
2461 if (retval) {
2462 DEBC(printk(ST_DEB_MSG "%s: Compression mode page not supported.\n",
2463 name));
2464 return (-EIO);
2465 }
2466
2467 mpoffs = MODE_HEADER_LENGTH + b_data[MH_OFF_BDESCS_LENGTH];
2468 DEBC(printk(ST_DEB_MSG "%s: Compression state is %d.\n", name,
2469 (b_data[mpoffs + CP_OFF_DCE_DCC] & DCE_MASK ? 1 : 0)));
2470
2471 /* Check if compression can be changed */
2472 if ((b_data[mpoffs + CP_OFF_DCE_DCC] & DCC_MASK) == 0) {
2473 DEBC(printk(ST_DEB_MSG "%s: Compression not supported.\n", name));
2474 return (-EIO);
2475 }
2476
2477 /* Do the change */
2478 if (state) {
2479 b_data[mpoffs + CP_OFF_DCE_DCC] |= DCE_MASK;
2480 if (STp->c_algo != 0)
2481 b_data[mpoffs + CP_OFF_C_ALGO] = STp->c_algo;
2482 }
2483 else {
2484 b_data[mpoffs + CP_OFF_DCE_DCC] &= ~DCE_MASK;
2485 if (STp->c_algo != 0)
2486 b_data[mpoffs + CP_OFF_C_ALGO] = 0; /* no compression */
2487 }
2488
2489 retval = write_mode_page(STp, COMPRESSION_PAGE, 0);
2490 if (retval) {
2491 DEBC(printk(ST_DEB_MSG "%s: Compression change failed.\n", name));
2492 return (-EIO);
2493 }
2494 DEBC(printk(ST_DEB_MSG "%s: Compression state changed to %d.\n",
2495 name, state));
2496
2497 STp->compression_changed = 1;
2498 return 0;
2499 }
2500
2501
2502 /* Process the load and unload commands (does unload if the load code is zero) */
2503 static int do_load_unload(struct scsi_tape *STp, struct file *filp, int load_code)
2504 {
2505 int retval = (-EIO), timeout;
2506 DEB( char *name = tape_name(STp); )
2507 unsigned char cmd[MAX_COMMAND_SIZE];
2508 struct st_partstat *STps;
2509 struct st_request *SRpnt;
2510
2511 if (STp->ready != ST_READY && !load_code) {
2512 if (STp->ready == ST_NO_TAPE)
2513 return (-ENOMEDIUM);
2514 else
2515 return (-EIO);
2516 }
2517
2518 memset(cmd, 0, MAX_COMMAND_SIZE);
2519 cmd[0] = START_STOP;
2520 if (load_code)
2521 cmd[4] |= 1;
2522 /*
2523 * If arg >= 1 && arg <= 6 Enhanced load/unload in HP C1553A
2524 */
2525 if (load_code >= 1 + MT_ST_HPLOADER_OFFSET
2526 && load_code <= 6 + MT_ST_HPLOADER_OFFSET) {
2527 DEBC(printk(ST_DEB_MSG "%s: Enhanced %sload slot %2d.\n",
2528 name, (cmd[4]) ? "" : "un",
2529 load_code - MT_ST_HPLOADER_OFFSET));
2530 cmd[3] = load_code - MT_ST_HPLOADER_OFFSET; /* MediaID field of C1553A */
2531 }
2532 if (STp->immediate) {
2533 cmd[1] = 1; /* Don't wait for completion */
2534 timeout = STp->device->request_queue->rq_timeout;
2535 }
2536 else
2537 timeout = STp->long_timeout;
2538
2539 DEBC(
2540 if (!load_code)
2541 printk(ST_DEB_MSG "%s: Unloading tape.\n", name);
2542 else
2543 printk(ST_DEB_MSG "%s: Loading tape.\n", name);
2544 );
2545
2546 SRpnt = st_do_scsi(NULL, STp, cmd, 0, DMA_NONE,
2547 timeout, MAX_RETRIES, 1);
2548 if (!SRpnt)
2549 return (STp->buffer)->syscall_result;
2550
2551 retval = (STp->buffer)->syscall_result;
2552 st_release_request(SRpnt);
2553
2554 if (!retval) { /* SCSI command successful */
2555
2556 if (!load_code) {
2557 STp->rew_at_close = 0;
2558 STp->ready = ST_NO_TAPE;
2559 }
2560 else {
2561 STp->rew_at_close = STp->autorew_dev;
2562 retval = check_tape(STp, filp);
2563 if (retval > 0)
2564 retval = 0;
2565 }
2566 }
2567 else {
2568 STps = &(STp->ps[STp->partition]);
2569 STps->drv_file = STps->drv_block = (-1);
2570 }
2571
2572 return retval;
2573 }
2574 \f
2575 #if DEBUG
2576 #define ST_DEB_FORWARD 0
2577 #define ST_DEB_BACKWARD 1
2578 static void deb_space_print(char *name, int direction, char *units, unsigned char *cmd)
2579 {
2580 s32 sc;
2581
2582 sc = cmd[2] & 0x80 ? 0xff000000 : 0;
2583 sc |= (cmd[2] << 16) | (cmd[3] << 8) | cmd[4];
2584 if (direction)
2585 sc = -sc;
2586 printk(ST_DEB_MSG "%s: Spacing tape %s over %d %s.\n", name,
2587 direction ? "backward" : "forward", sc, units);
2588 }
2589 #endif
2590
2591
2592 /* Internal ioctl function */
2593 static int st_int_ioctl(struct scsi_tape *STp, unsigned int cmd_in, unsigned long arg)
2594 {
2595 int timeout;
2596 long ltmp;
2597 int ioctl_result;
2598 int chg_eof = 1;
2599 unsigned char cmd[MAX_COMMAND_SIZE];
2600 struct st_request *SRpnt;
2601 struct st_partstat *STps;
2602 int fileno, blkno, at_sm, undone;
2603 int datalen = 0, direction = DMA_NONE;
2604 char *name = tape_name(STp);
2605
2606 WARN_ON(STp->buffer->do_dio != 0);
2607 if (STp->ready != ST_READY) {
2608 if (STp->ready == ST_NO_TAPE)
2609 return (-ENOMEDIUM);
2610 else
2611 return (-EIO);
2612 }
2613 timeout = STp->long_timeout;
2614 STps = &(STp->ps[STp->partition]);
2615 fileno = STps->drv_file;
2616 blkno = STps->drv_block;
2617 at_sm = STps->at_sm;
2618
2619 memset(cmd, 0, MAX_COMMAND_SIZE);
2620 switch (cmd_in) {
2621 case MTFSFM:
2622 chg_eof = 0; /* Changed from the FSF after this */
2623 case MTFSF:
2624 cmd[0] = SPACE;
2625 cmd[1] = 0x01; /* Space FileMarks */
2626 cmd[2] = (arg >> 16);
2627 cmd[3] = (arg >> 8);
2628 cmd[4] = arg;
2629 DEBC(deb_space_print(name, ST_DEB_FORWARD, "filemarks", cmd);)
2630 if (fileno >= 0)
2631 fileno += arg;
2632 blkno = 0;
2633 at_sm &= (arg == 0);
2634 break;
2635 case MTBSFM:
2636 chg_eof = 0; /* Changed from the FSF after this */
2637 case MTBSF:
2638 cmd[0] = SPACE;
2639 cmd[1] = 0x01; /* Space FileMarks */
2640 ltmp = (-arg);
2641 cmd[2] = (ltmp >> 16);
2642 cmd[3] = (ltmp >> 8);
2643 cmd[4] = ltmp;
2644 DEBC(deb_space_print(name, ST_DEB_BACKWARD, "filemarks", cmd);)
2645 if (fileno >= 0)
2646 fileno -= arg;
2647 blkno = (-1); /* We can't know the block number */
2648 at_sm &= (arg == 0);
2649 break;
2650 case MTFSR:
2651 cmd[0] = SPACE;
2652 cmd[1] = 0x00; /* Space Blocks */
2653 cmd[2] = (arg >> 16);
2654 cmd[3] = (arg >> 8);
2655 cmd[4] = arg;
2656 DEBC(deb_space_print(name, ST_DEB_FORWARD, "blocks", cmd);)
2657 if (blkno >= 0)
2658 blkno += arg;
2659 at_sm &= (arg == 0);
2660 break;
2661 case MTBSR:
2662 cmd[0] = SPACE;
2663 cmd[1] = 0x00; /* Space Blocks */
2664 ltmp = (-arg);
2665 cmd[2] = (ltmp >> 16);
2666 cmd[3] = (ltmp >> 8);
2667 cmd[4] = ltmp;
2668 DEBC(deb_space_print(name, ST_DEB_BACKWARD, "blocks", cmd);)
2669 if (blkno >= 0)
2670 blkno -= arg;
2671 at_sm &= (arg == 0);
2672 break;
2673 case MTFSS:
2674 cmd[0] = SPACE;
2675 cmd[1] = 0x04; /* Space Setmarks */
2676 cmd[2] = (arg >> 16);
2677 cmd[3] = (arg >> 8);
2678 cmd[4] = arg;
2679 DEBC(deb_space_print(name, ST_DEB_FORWARD, "setmarks", cmd);)
2680 if (arg != 0) {
2681 blkno = fileno = (-1);
2682 at_sm = 1;
2683 }
2684 break;
2685 case MTBSS:
2686 cmd[0] = SPACE;
2687 cmd[1] = 0x04; /* Space Setmarks */
2688 ltmp = (-arg);
2689 cmd[2] = (ltmp >> 16);
2690 cmd[3] = (ltmp >> 8);
2691 cmd[4] = ltmp;
2692 DEBC(deb_space_print(name, ST_DEB_BACKWARD, "setmarks", cmd);)
2693 if (arg != 0) {
2694 blkno = fileno = (-1);
2695 at_sm = 1;
2696 }
2697 break;
2698 case MTWEOF:
2699 case MTWEOFI:
2700 case MTWSM:
2701 if (STp->write_prot)
2702 return (-EACCES);
2703 cmd[0] = WRITE_FILEMARKS;
2704 if (cmd_in == MTWSM)
2705 cmd[1] = 2;
2706 if (cmd_in == MTWEOFI)
2707 cmd[1] |= 1;
2708 cmd[2] = (arg >> 16);
2709 cmd[3] = (arg >> 8);
2710 cmd[4] = arg;
2711 timeout = STp->device->request_queue->rq_timeout;
2712 DEBC(
2713 if (cmd_in != MTWSM)
2714 printk(ST_DEB_MSG "%s: Writing %d filemarks.\n", name,
2715 cmd[2] * 65536 + cmd[3] * 256 + cmd[4]);
2716 else
2717 printk(ST_DEB_MSG "%s: Writing %d setmarks.\n", name,
2718 cmd[2] * 65536 + cmd[3] * 256 + cmd[4]);
2719 )
2720 if (fileno >= 0)
2721 fileno += arg;
2722 blkno = 0;
2723 at_sm = (cmd_in == MTWSM);
2724 break;
2725 case MTREW:
2726 cmd[0] = REZERO_UNIT;
2727 if (STp->immediate) {
2728 cmd[1] = 1; /* Don't wait for completion */
2729 timeout = STp->device->request_queue->rq_timeout;
2730 }
2731 DEBC(printk(ST_DEB_MSG "%s: Rewinding tape.\n", name));
2732 fileno = blkno = at_sm = 0;
2733 break;
2734 case MTNOP:
2735 DEBC(printk(ST_DEB_MSG "%s: No op on tape.\n", name));
2736 return 0; /* Should do something ? */
2737 break;
2738 case MTRETEN:
2739 cmd[0] = START_STOP;
2740 if (STp->immediate) {
2741 cmd[1] = 1; /* Don't wait for completion */
2742 timeout = STp->device->request_queue->rq_timeout;
2743 }
2744 cmd[4] = 3;
2745 DEBC(printk(ST_DEB_MSG "%s: Retensioning tape.\n", name));
2746 fileno = blkno = at_sm = 0;
2747 break;
2748 case MTEOM:
2749 if (!STp->fast_mteom) {
2750 /* space to the end of tape */
2751 ioctl_result = st_int_ioctl(STp, MTFSF, 0x7fffff);
2752 fileno = STps->drv_file;
2753 if (STps->eof >= ST_EOD_1)
2754 return 0;
2755 /* The next lines would hide the number of spaced FileMarks
2756 That's why I inserted the previous lines. I had no luck
2757 with detecting EOM with FSF, so we go now to EOM.
2758 Joerg Weule */
2759 } else
2760 fileno = (-1);
2761 cmd[0] = SPACE;
2762 cmd[1] = 3;
2763 DEBC(printk(ST_DEB_MSG "%s: Spacing to end of recorded medium.\n",
2764 name));
2765 blkno = -1;
2766 at_sm = 0;
2767 break;
2768 case MTERASE:
2769 if (STp->write_prot)
2770 return (-EACCES);
2771 cmd[0] = ERASE;
2772 cmd[1] = (arg ? 1 : 0); /* Long erase with non-zero argument */
2773 if (STp->immediate) {
2774 cmd[1] |= 2; /* Don't wait for completion */
2775 timeout = STp->device->request_queue->rq_timeout;
2776 }
2777 else
2778 timeout = STp->long_timeout * 8;
2779
2780 DEBC(printk(ST_DEB_MSG "%s: Erasing tape.\n", name));
2781 fileno = blkno = at_sm = 0;
2782 break;
2783 case MTSETBLK: /* Set block length */
2784 case MTSETDENSITY: /* Set tape density */
2785 case MTSETDRVBUFFER: /* Set drive buffering */
2786 case SET_DENS_AND_BLK: /* Set density and block size */
2787 chg_eof = 0;
2788 if (STp->dirty || (STp->buffer)->buffer_bytes != 0)
2789 return (-EIO); /* Not allowed if data in buffer */
2790 if ((cmd_in == MTSETBLK || cmd_in == SET_DENS_AND_BLK) &&
2791 (arg & MT_ST_BLKSIZE_MASK) != 0 &&
2792 STp->max_block > 0 &&
2793 ((arg & MT_ST_BLKSIZE_MASK) < STp->min_block ||
2794 (arg & MT_ST_BLKSIZE_MASK) > STp->max_block)) {
2795 printk(KERN_WARNING "%s: Illegal block size.\n", name);
2796 return (-EINVAL);
2797 }
2798 cmd[0] = MODE_SELECT;
2799 if ((STp->use_pf & USE_PF))
2800 cmd[1] = MODE_SELECT_PAGE_FORMAT;
2801 cmd[4] = datalen = 12;
2802 direction = DMA_TO_DEVICE;
2803
2804 memset((STp->buffer)->b_data, 0, 12);
2805 if (cmd_in == MTSETDRVBUFFER)
2806 (STp->buffer)->b_data[2] = (arg & 7) << 4;
2807 else
2808 (STp->buffer)->b_data[2] =
2809 STp->drv_buffer << 4;
2810 (STp->buffer)->b_data[3] = 8; /* block descriptor length */
2811 if (cmd_in == MTSETDENSITY) {
2812 (STp->buffer)->b_data[4] = arg;
2813 STp->density_changed = 1; /* At least we tried ;-) */
2814 } else if (cmd_in == SET_DENS_AND_BLK)
2815 (STp->buffer)->b_data[4] = arg >> 24;
2816 else
2817 (STp->buffer)->b_data[4] = STp->density;
2818 if (cmd_in == MTSETBLK || cmd_in == SET_DENS_AND_BLK) {
2819 ltmp = arg & MT_ST_BLKSIZE_MASK;
2820 if (cmd_in == MTSETBLK)
2821 STp->blksize_changed = 1; /* At least we tried ;-) */
2822 } else
2823 ltmp = STp->block_size;
2824 (STp->buffer)->b_data[9] = (ltmp >> 16);
2825 (STp->buffer)->b_data[10] = (ltmp >> 8);
2826 (STp->buffer)->b_data[11] = ltmp;
2827 timeout = STp->device->request_queue->rq_timeout;
2828 DEBC(
2829 if (cmd_in == MTSETBLK || cmd_in == SET_DENS_AND_BLK)
2830 printk(ST_DEB_MSG
2831 "%s: Setting block size to %d bytes.\n", name,
2832 (STp->buffer)->b_data[9] * 65536 +
2833 (STp->buffer)->b_data[10] * 256 +
2834 (STp->buffer)->b_data[11]);
2835 if (cmd_in == MTSETDENSITY || cmd_in == SET_DENS_AND_BLK)
2836 printk(ST_DEB_MSG
2837 "%s: Setting density code to %x.\n", name,
2838 (STp->buffer)->b_data[4]);
2839 if (cmd_in == MTSETDRVBUFFER)
2840 printk(ST_DEB_MSG
2841 "%s: Setting drive buffer code to %d.\n", name,
2842 ((STp->buffer)->b_data[2] >> 4) & 7);
2843 )
2844 break;
2845 default:
2846 return (-ENOSYS);
2847 }
2848
2849 SRpnt = st_do_scsi(NULL, STp, cmd, datalen, direction,
2850 timeout, MAX_RETRIES, 1);
2851 if (!SRpnt)
2852 return (STp->buffer)->syscall_result;
2853
2854 ioctl_result = (STp->buffer)->syscall_result;
2855
2856 if (!ioctl_result) { /* SCSI command successful */
2857 st_release_request(SRpnt);
2858 SRpnt = NULL;
2859 STps->drv_block = blkno;
2860 STps->drv_file = fileno;
2861 STps->at_sm = at_sm;
2862
2863 if (cmd_in == MTBSFM)
2864 ioctl_result = st_int_ioctl(STp, MTFSF, 1);
2865 else if (cmd_in == MTFSFM)
2866 ioctl_result = st_int_ioctl(STp, MTBSF, 1);
2867
2868 if (cmd_in == MTSETBLK || cmd_in == SET_DENS_AND_BLK) {
2869 STp->block_size = arg & MT_ST_BLKSIZE_MASK;
2870 if (STp->block_size != 0) {
2871 (STp->buffer)->buffer_blocks =
2872 (STp->buffer)->buffer_size / STp->block_size;
2873 }
2874 (STp->buffer)->buffer_bytes = (STp->buffer)->read_pointer = 0;
2875 if (cmd_in == SET_DENS_AND_BLK)
2876 STp->density = arg >> MT_ST_DENSITY_SHIFT;
2877 } else if (cmd_in == MTSETDRVBUFFER)
2878 STp->drv_buffer = (arg & 7);
2879 else if (cmd_in == MTSETDENSITY)
2880 STp->density = arg;
2881
2882 if (cmd_in == MTEOM)
2883 STps->eof = ST_EOD;
2884 else if (cmd_in == MTFSF)
2885 STps->eof = ST_FM;
2886 else if (chg_eof)
2887 STps->eof = ST_NOEOF;
2888
2889 if (cmd_in == MTWEOF || cmd_in == MTWEOFI)
2890 STps->rw = ST_IDLE; /* prevent automatic WEOF at close */
2891 } else { /* SCSI command was not completely successful. Don't return
2892 from this block without releasing the SCSI command block! */
2893 struct st_cmdstatus *cmdstatp = &STp->buffer->cmdstat;
2894
2895 if (cmdstatp->flags & SENSE_EOM) {
2896 if (cmd_in != MTBSF && cmd_in != MTBSFM &&
2897 cmd_in != MTBSR && cmd_in != MTBSS)
2898 STps->eof = ST_EOM_OK;
2899 STps->drv_block = 0;
2900 }
2901
2902 if (cmdstatp->remainder_valid)
2903 undone = (int)cmdstatp->uremainder64;
2904 else
2905 undone = 0;
2906
2907 if ((cmd_in == MTWEOF || cmd_in == MTWEOFI) &&
2908 cmdstatp->have_sense &&
2909 (cmdstatp->flags & SENSE_EOM)) {
2910 if (cmdstatp->sense_hdr.sense_key == NO_SENSE ||
2911 cmdstatp->sense_hdr.sense_key == RECOVERED_ERROR) {
2912 ioctl_result = 0; /* EOF(s) written successfully at EOM */
2913 STps->eof = ST_NOEOF;
2914 } else { /* Writing EOF(s) failed */
2915 if (fileno >= 0)
2916 fileno -= undone;
2917 if (undone < arg)
2918 STps->eof = ST_NOEOF;
2919 }
2920 STps->drv_file = fileno;
2921 } else if ((cmd_in == MTFSF) || (cmd_in == MTFSFM)) {
2922 if (fileno >= 0)
2923 STps->drv_file = fileno - undone;
2924 else
2925 STps->drv_file = fileno;
2926 STps->drv_block = -1;
2927 STps->eof = ST_NOEOF;
2928 } else if ((cmd_in == MTBSF) || (cmd_in == MTBSFM)) {
2929 if (arg > 0 && undone < 0) /* Some drives get this wrong */
2930 undone = (-undone);
2931 if (STps->drv_file >= 0)
2932 STps->drv_file = fileno + undone;
2933 STps->drv_block = 0;
2934 STps->eof = ST_NOEOF;
2935 } else if (cmd_in == MTFSR) {
2936 if (cmdstatp->flags & SENSE_FMK) { /* Hit filemark */
2937 if (STps->drv_file >= 0)
2938 STps->drv_file++;
2939 STps->drv_block = 0;
2940 STps->eof = ST_FM;
2941 } else {
2942 if (blkno >= undone)
2943 STps->drv_block = blkno - undone;
2944 else
2945 STps->drv_block = (-1);
2946 STps->eof = ST_NOEOF;
2947 }
2948 } else if (cmd_in == MTBSR) {
2949 if (cmdstatp->flags & SENSE_FMK) { /* Hit filemark */
2950 STps->drv_file--;
2951 STps->drv_block = (-1);
2952 } else {
2953 if (arg > 0 && undone < 0) /* Some drives get this wrong */
2954 undone = (-undone);
2955 if (STps->drv_block >= 0)
2956 STps->drv_block = blkno + undone;
2957 }
2958 STps->eof = ST_NOEOF;
2959 } else if (cmd_in == MTEOM) {
2960 STps->drv_file = (-1);
2961 STps->drv_block = (-1);
2962 STps->eof = ST_EOD;
2963 } else if (cmd_in == MTSETBLK ||
2964 cmd_in == MTSETDENSITY ||
2965 cmd_in == MTSETDRVBUFFER ||
2966 cmd_in == SET_DENS_AND_BLK) {
2967 if (cmdstatp->sense_hdr.sense_key == ILLEGAL_REQUEST &&
2968 !(STp->use_pf & PF_TESTED)) {
2969 /* Try the other possible state of Page Format if not
2970 already tried */
2971 STp->use_pf = (STp->use_pf ^ USE_PF) | PF_TESTED;
2972 st_release_request(SRpnt);
2973 SRpnt = NULL;
2974 return st_int_ioctl(STp, cmd_in, arg);
2975 }
2976 } else if (chg_eof)
2977 STps->eof = ST_NOEOF;
2978
2979 if (cmdstatp->sense_hdr.sense_key == BLANK_CHECK)
2980 STps->eof = ST_EOD;
2981
2982 st_release_request(SRpnt);
2983 SRpnt = NULL;
2984 }
2985
2986 return ioctl_result;
2987 }
2988 \f
2989
2990 /* Get the tape position. If bt == 2, arg points into a kernel space mt_loc
2991 structure. */
2992
2993 static int get_location(struct scsi_tape *STp, unsigned int *block, int *partition,
2994 int logical)
2995 {
2996 int result;
2997 unsigned char scmd[MAX_COMMAND_SIZE];
2998 struct st_request *SRpnt;
2999 DEB( char *name = tape_name(STp); )
3000
3001 if (STp->ready != ST_READY)
3002 return (-EIO);
3003
3004 memset(scmd, 0, MAX_COMMAND_SIZE);
3005 if ((STp->device)->scsi_level < SCSI_2) {
3006 scmd[0] = QFA_REQUEST_BLOCK;
3007 scmd[4] = 3;
3008 } else {
3009 scmd[0] = READ_POSITION;
3010 if (!logical && !STp->scsi2_logical)
3011 scmd[1] = 1;
3012 }
3013 SRpnt = st_do_scsi(NULL, STp, scmd, 20, DMA_FROM_DEVICE,
3014 STp->device->request_queue->rq_timeout,
3015 MAX_READY_RETRIES, 1);
3016 if (!SRpnt)
3017 return (STp->buffer)->syscall_result;
3018
3019 if ((STp->buffer)->syscall_result != 0 ||
3020 (STp->device->scsi_level >= SCSI_2 &&
3021 ((STp->buffer)->b_data[0] & 4) != 0)) {
3022 *block = *partition = 0;
3023 DEBC(printk(ST_DEB_MSG "%s: Can't read tape position.\n", name));
3024 result = (-EIO);
3025 } else {
3026 result = 0;
3027 if ((STp->device)->scsi_level < SCSI_2) {
3028 *block = ((STp->buffer)->b_data[0] << 16)
3029 + ((STp->buffer)->b_data[1] << 8)
3030 + (STp->buffer)->b_data[2];
3031 *partition = 0;
3032 } else {
3033 *block = ((STp->buffer)->b_data[4] << 24)
3034 + ((STp->buffer)->b_data[5] << 16)
3035 + ((STp->buffer)->b_data[6] << 8)
3036 + (STp->buffer)->b_data[7];
3037 *partition = (STp->buffer)->b_data[1];
3038 if (((STp->buffer)->b_data[0] & 0x80) &&
3039 (STp->buffer)->b_data[1] == 0) /* BOP of partition 0 */
3040 STp->ps[0].drv_block = STp->ps[0].drv_file = 0;
3041 }
3042 DEBC(printk(ST_DEB_MSG "%s: Got tape pos. blk %d part %d.\n", name,
3043 *block, *partition));
3044 }
3045 st_release_request(SRpnt);
3046 SRpnt = NULL;
3047
3048 return result;
3049 }
3050
3051
3052 /* Set the tape block and partition. Negative partition means that only the
3053 block should be set in vendor specific way. */
3054 static int set_location(struct scsi_tape *STp, unsigned int block, int partition,
3055 int logical)
3056 {
3057 struct st_partstat *STps;
3058 int result, p;
3059 unsigned int blk;
3060 int timeout;
3061 unsigned char scmd[MAX_COMMAND_SIZE];
3062 struct st_request *SRpnt;
3063 DEB( char *name = tape_name(STp); )
3064
3065 if (STp->ready != ST_READY)
3066 return (-EIO);
3067 timeout = STp->long_timeout;
3068 STps = &(STp->ps[STp->partition]);
3069
3070 DEBC(printk(ST_DEB_MSG "%s: Setting block to %d and partition to %d.\n",
3071 name, block, partition));
3072 DEB(if (partition < 0)
3073 return (-EIO); )
3074
3075 /* Update the location at the partition we are leaving */
3076 if ((!STp->can_partitions && partition != 0) ||
3077 partition >= ST_NBR_PARTITIONS)
3078 return (-EINVAL);
3079 if (partition != STp->partition) {
3080 if (get_location(STp, &blk, &p, 1))
3081 STps->last_block_valid = 0;
3082 else {
3083 STps->last_block_valid = 1;
3084 STps->last_block_visited = blk;
3085 DEBC(printk(ST_DEB_MSG
3086 "%s: Visited block %d for partition %d saved.\n",
3087 name, blk, STp->partition));
3088 }
3089 }
3090
3091 memset(scmd, 0, MAX_COMMAND_SIZE);
3092 if ((STp->device)->scsi_level < SCSI_2) {
3093 scmd[0] = QFA_SEEK_BLOCK;
3094 scmd[2] = (block >> 16);
3095 scmd[3] = (block >> 8);
3096 scmd[4] = block;
3097 scmd[5] = 0;
3098 } else {
3099 scmd[0] = SEEK_10;
3100 scmd[3] = (block >> 24);
3101 scmd[4] = (block >> 16);
3102 scmd[5] = (block >> 8);
3103 scmd[6] = block;
3104 if (!logical && !STp->scsi2_logical)
3105 scmd[1] = 4;
3106 if (STp->partition != partition) {
3107 scmd[1] |= 2;
3108 scmd[8] = partition;
3109 DEBC(printk(ST_DEB_MSG
3110 "%s: Trying to change partition from %d to %d\n",
3111 name, STp->partition, partition));
3112 }
3113 }
3114 if (STp->immediate) {
3115 scmd[1] |= 1; /* Don't wait for completion */
3116 timeout = STp->device->request_queue->rq_timeout;
3117 }
3118
3119 SRpnt = st_do_scsi(NULL, STp, scmd, 0, DMA_NONE,
3120 timeout, MAX_READY_RETRIES, 1);
3121 if (!SRpnt)
3122 return (STp->buffer)->syscall_result;
3123
3124 STps->drv_block = STps->drv_file = (-1);
3125 STps->eof = ST_NOEOF;
3126 if ((STp->buffer)->syscall_result != 0) {
3127 result = (-EIO);
3128 if (STp->can_partitions &&
3129 (STp->device)->scsi_level >= SCSI_2 &&
3130 (p = find_partition(STp)) >= 0)
3131 STp->partition = p;
3132 } else {
3133 if (STp->can_partitions) {
3134 STp->partition = partition;
3135 STps = &(STp->ps[partition]);
3136 if (!STps->last_block_valid ||
3137 STps->last_block_visited != block) {
3138 STps->at_sm = 0;
3139 STps->rw = ST_IDLE;
3140 }
3141 } else
3142 STps->at_sm = 0;
3143 if (block == 0)
3144 STps->drv_block = STps->drv_file = 0;
3145 result = 0;
3146 }
3147
3148 st_release_request(SRpnt);
3149 SRpnt = NULL;
3150
3151 return result;
3152 }
3153
3154
3155 /* Find the current partition number for the drive status. Called from open and
3156 returns either partition number of negative error code. */
3157 static int find_partition(struct scsi_tape *STp)
3158 {
3159 int i, partition;
3160 unsigned int block;
3161
3162 if ((i = get_location(STp, &block, &partition, 1)) < 0)
3163 return i;
3164 if (partition >= ST_NBR_PARTITIONS)
3165 return (-EIO);
3166 return partition;
3167 }
3168
3169
3170 /* Change the partition if necessary */
3171 static int switch_partition(struct scsi_tape *STp)
3172 {
3173 struct st_partstat *STps;
3174
3175 if (STp->partition == STp->new_partition)
3176 return 0;
3177 STps = &(STp->ps[STp->new_partition]);
3178 if (!STps->last_block_valid)
3179 STps->last_block_visited = 0;
3180 return set_location(STp, STps->last_block_visited, STp->new_partition, 1);
3181 }
3182 \f
3183 /* Functions for reading and writing the medium partition mode page. */
3184
3185 #define PART_PAGE 0x11
3186 #define PART_PAGE_FIXED_LENGTH 8
3187
3188 #define PP_OFF_MAX_ADD_PARTS 2
3189 #define PP_OFF_NBR_ADD_PARTS 3
3190 #define PP_OFF_FLAGS 4
3191 #define PP_OFF_PART_UNITS 6
3192 #define PP_OFF_RESERVED 7
3193
3194 #define PP_BIT_IDP 0x20
3195 #define PP_MSK_PSUM_MB 0x10
3196
3197 /* Get the number of partitions on the tape. As a side effect reads the
3198 mode page into the tape buffer. */
3199 static int nbr_partitions(struct scsi_tape *STp)
3200 {
3201 int result;
3202 DEB( char *name = tape_name(STp); )
3203
3204 if (STp->ready != ST_READY)
3205 return (-EIO);
3206
3207 result = read_mode_page(STp, PART_PAGE, 1);
3208
3209 if (result) {
3210 DEBC(printk(ST_DEB_MSG "%s: Can't read medium partition page.\n",
3211 name));
3212 result = (-EIO);
3213 } else {
3214 result = (STp->buffer)->b_data[MODE_HEADER_LENGTH +
3215 PP_OFF_NBR_ADD_PARTS] + 1;
3216 DEBC(printk(ST_DEB_MSG "%s: Number of partitions %d.\n", name, result));
3217 }
3218
3219 return result;
3220 }
3221
3222
3223 /* Partition the tape into two partitions if size > 0 or one partition if
3224 size == 0.
3225
3226 The block descriptors are read and written because Sony SDT-7000 does not
3227 work without this (suggestion from Michael Schaefer <Michael.Schaefer@dlr.de>).
3228
3229 My HP C1533A drive returns only one partition size field. This is used to
3230 set the size of partition 1. There is no size field for the default partition.
3231 Michael Schaefer's Sony SDT-7000 returns two descriptors and the second is
3232 used to set the size of partition 1 (this is what the SCSI-3 standard specifies).
3233 The following algorithm is used to accommodate both drives: if the number of
3234 partition size fields is greater than the maximum number of additional partitions
3235 in the mode page, the second field is used. Otherwise the first field is used.
3236
3237 For Seagate DDS drives the page length must be 8 when no partitions is defined
3238 and 10 when 1 partition is defined (information from Eric Lee Green). This is
3239 is acceptable also to some other old drives and enforced if the first partition
3240 size field is used for the first additional partition size.
3241 */
3242 static int partition_tape(struct scsi_tape *STp, int size)
3243 {
3244 char *name = tape_name(STp);
3245 int result;
3246 int pgo, psd_cnt, psdo;
3247 unsigned char *bp;
3248
3249 result = read_mode_page(STp, PART_PAGE, 0);
3250 if (result) {
3251 DEBC(printk(ST_DEB_MSG "%s: Can't read partition mode page.\n", name));
3252 return result;
3253 }
3254 /* The mode page is in the buffer. Let's modify it and write it. */
3255 bp = (STp->buffer)->b_data;
3256 pgo = MODE_HEADER_LENGTH + bp[MH_OFF_BDESCS_LENGTH];
3257 DEBC(printk(ST_DEB_MSG "%s: Partition page length is %d bytes.\n",
3258 name, bp[pgo + MP_OFF_PAGE_LENGTH] + 2));
3259
3260 psd_cnt = (bp[pgo + MP_OFF_PAGE_LENGTH] + 2 - PART_PAGE_FIXED_LENGTH) / 2;
3261 psdo = pgo + PART_PAGE_FIXED_LENGTH;
3262 if (psd_cnt > bp[pgo + PP_OFF_MAX_ADD_PARTS]) {
3263 bp[psdo] = bp[psdo + 1] = 0xff; /* Rest of the tape */
3264 psdo += 2;
3265 }
3266 memset(bp + psdo, 0, bp[pgo + PP_OFF_NBR_ADD_PARTS] * 2);
3267
3268 DEBC(printk("%s: psd_cnt %d, max.parts %d, nbr_parts %d\n", name,
3269 psd_cnt, bp[pgo + PP_OFF_MAX_ADD_PARTS],
3270 bp[pgo + PP_OFF_NBR_ADD_PARTS]));
3271
3272 if (size <= 0) {
3273 bp[pgo + PP_OFF_NBR_ADD_PARTS] = 0;
3274 if (psd_cnt <= bp[pgo + PP_OFF_MAX_ADD_PARTS])
3275 bp[pgo + MP_OFF_PAGE_LENGTH] = 6;
3276 DEBC(printk(ST_DEB_MSG "%s: Formatting tape with one partition.\n",
3277 name));
3278 } else {
3279 bp[psdo] = (size >> 8) & 0xff;
3280 bp[psdo + 1] = size & 0xff;
3281 bp[pgo + 3] = 1;
3282 if (bp[pgo + MP_OFF_PAGE_LENGTH] < 8)
3283 bp[pgo + MP_OFF_PAGE_LENGTH] = 8;
3284 DEBC(printk(ST_DEB_MSG
3285 "%s: Formatting tape with two partitions (1 = %d MB).\n",
3286 name, size));
3287 }
3288 bp[pgo + PP_OFF_PART_UNITS] = 0;
3289 bp[pgo + PP_OFF_RESERVED] = 0;
3290 bp[pgo + PP_OFF_FLAGS] = PP_BIT_IDP | PP_MSK_PSUM_MB;
3291
3292 result = write_mode_page(STp, PART_PAGE, 1);
3293 if (result) {
3294 printk(KERN_INFO "%s: Partitioning of tape failed.\n", name);
3295 result = (-EIO);
3296 }
3297
3298 return result;
3299 }
3300 \f
3301
3302
3303 /* The ioctl command */
3304 static long st_ioctl(struct file *file, unsigned int cmd_in, unsigned long arg)
3305 {
3306 int i, cmd_nr, cmd_type, bt;
3307 int retval = 0;
3308 unsigned int blk;
3309 struct scsi_tape *STp = file->private_data;
3310 struct st_modedef *STm;
3311 struct st_partstat *STps;
3312 char *name = tape_name(STp);
3313 void __user *p = (void __user *)arg;
3314
3315 if (mutex_lock_interruptible(&STp->lock))
3316 return -ERESTARTSYS;
3317
3318 DEB(
3319 if (debugging && !STp->in_use) {
3320 printk(ST_DEB_MSG "%s: Incorrect device.\n", name);
3321 retval = (-EIO);
3322 goto out;
3323 } ) /* end DEB */
3324
3325 STm = &(STp->modes[STp->current_mode]);
3326 STps = &(STp->ps[STp->partition]);
3327
3328 /*
3329 * If we are in the middle of error recovery, don't let anyone
3330 * else try and use this device. Also, if error recovery fails, it
3331 * may try and take the device offline, in which case all further
3332 * access to the device is prohibited.
3333 */
3334 retval = scsi_nonblockable_ioctl(STp->device, cmd_in, p,
3335 file->f_flags & O_NDELAY);
3336 if (!scsi_block_when_processing_errors(STp->device) || retval != -ENODEV)
3337 goto out;
3338 retval = 0;
3339
3340 cmd_type = _IOC_TYPE(cmd_in);
3341 cmd_nr = _IOC_NR(cmd_in);
3342
3343 if (cmd_type == _IOC_TYPE(MTIOCTOP) && cmd_nr == _IOC_NR(MTIOCTOP)) {
3344 struct mtop mtc;
3345
3346 if (_IOC_SIZE(cmd_in) != sizeof(mtc)) {
3347 retval = (-EINVAL);
3348 goto out;
3349 }
3350
3351 i = copy_from_user(&mtc, p, sizeof(struct mtop));
3352 if (i) {
3353 retval = (-EFAULT);
3354 goto out;
3355 }
3356
3357 if (mtc.mt_op == MTSETDRVBUFFER && !capable(CAP_SYS_ADMIN)) {
3358 printk(KERN_WARNING
3359 "%s: MTSETDRVBUFFER only allowed for root.\n", name);
3360 retval = (-EPERM);
3361 goto out;
3362 }
3363 if (!STm->defined &&
3364 (mtc.mt_op != MTSETDRVBUFFER &&
3365 (mtc.mt_count & MT_ST_OPTIONS) == 0)) {
3366 retval = (-ENXIO);
3367 goto out;
3368 }
3369
3370 if (!STp->pos_unknown) {
3371
3372 if (STps->eof == ST_FM_HIT) {
3373 if (mtc.mt_op == MTFSF || mtc.mt_op == MTFSFM ||
3374 mtc.mt_op == MTEOM) {
3375 mtc.mt_count -= 1;
3376 if (STps->drv_file >= 0)
3377 STps->drv_file += 1;
3378 } else if (mtc.mt_op == MTBSF || mtc.mt_op == MTBSFM) {
3379 mtc.mt_count += 1;
3380 if (STps->drv_file >= 0)
3381 STps->drv_file += 1;
3382 }
3383 }
3384
3385 if (mtc.mt_op == MTSEEK) {
3386 /* Old position must be restored if partition will be
3387 changed */
3388 i = !STp->can_partitions ||
3389 (STp->new_partition != STp->partition);
3390 } else {
3391 i = mtc.mt_op == MTREW || mtc.mt_op == MTOFFL ||
3392 mtc.mt_op == MTRETEN || mtc.mt_op == MTEOM ||
3393 mtc.mt_op == MTLOCK || mtc.mt_op == MTLOAD ||
3394 mtc.mt_op == MTFSF || mtc.mt_op == MTFSFM ||
3395 mtc.mt_op == MTBSF || mtc.mt_op == MTBSFM ||
3396 mtc.mt_op == MTCOMPRESSION;
3397 }
3398 i = flush_buffer(STp, i);
3399 if (i < 0) {
3400 retval = i;
3401 goto out;
3402 }
3403 if (STps->rw == ST_WRITING &&
3404 (mtc.mt_op == MTREW || mtc.mt_op == MTOFFL ||
3405 mtc.mt_op == MTSEEK ||
3406 mtc.mt_op == MTBSF || mtc.mt_op == MTBSFM)) {
3407 i = st_int_ioctl(STp, MTWEOF, 1);
3408 if (i < 0) {
3409 retval = i;
3410 goto out;
3411 }
3412 if (mtc.mt_op == MTBSF || mtc.mt_op == MTBSFM)
3413 mtc.mt_count++;
3414 STps->rw = ST_IDLE;
3415 }
3416
3417 } else {
3418 /*
3419 * If there was a bus reset, block further access
3420 * to this device. If the user wants to rewind the tape,
3421 * then reset the flag and allow access again.
3422 */
3423 if (mtc.mt_op != MTREW &&
3424 mtc.mt_op != MTOFFL &&
3425 mtc.mt_op != MTRETEN &&
3426 mtc.mt_op != MTERASE &&
3427 mtc.mt_op != MTSEEK &&
3428 mtc.mt_op != MTEOM) {
3429 retval = (-EIO);
3430 goto out;
3431 }
3432 reset_state(STp);
3433 /* remove this when the midlevel properly clears was_reset */
3434 STp->device->was_reset = 0;
3435 }
3436
3437 if (mtc.mt_op != MTNOP && mtc.mt_op != MTSETBLK &&
3438 mtc.mt_op != MTSETDENSITY && mtc.mt_op != MTWSM &&
3439 mtc.mt_op != MTSETDRVBUFFER && mtc.mt_op != MTSETPART)
3440 STps->rw = ST_IDLE; /* Prevent automatic WEOF and fsf */
3441
3442 if (mtc.mt_op == MTOFFL && STp->door_locked != ST_UNLOCKED)
3443 do_door_lock(STp, 0); /* Ignore result! */
3444
3445 if (mtc.mt_op == MTSETDRVBUFFER &&
3446 (mtc.mt_count & MT_ST_OPTIONS) != 0) {
3447 retval = st_set_options(STp, mtc.mt_count);
3448 goto out;
3449 }
3450
3451 if (mtc.mt_op == MTSETPART) {
3452 if (!STp->can_partitions ||
3453 mtc.mt_count < 0 || mtc.mt_count >= ST_NBR_PARTITIONS) {
3454 retval = (-EINVAL);
3455 goto out;
3456 }
3457 if (mtc.mt_count >= STp->nbr_partitions &&
3458 (STp->nbr_partitions = nbr_partitions(STp)) < 0) {
3459 retval = (-EIO);
3460 goto out;
3461 }
3462 if (mtc.mt_count >= STp->nbr_partitions) {
3463 retval = (-EINVAL);
3464 goto out;
3465 }
3466 STp->new_partition = mtc.mt_count;
3467 retval = 0;
3468 goto out;
3469 }
3470
3471 if (mtc.mt_op == MTMKPART) {
3472 if (!STp->can_partitions) {
3473 retval = (-EINVAL);
3474 goto out;
3475 }
3476 if ((i = st_int_ioctl(STp, MTREW, 0)) < 0 ||
3477 (i = partition_tape(STp, mtc.mt_count)) < 0) {
3478 retval = i;
3479 goto out;
3480 }
3481 for (i = 0; i < ST_NBR_PARTITIONS; i++) {
3482 STp->ps[i].rw = ST_IDLE;
3483 STp->ps[i].at_sm = 0;
3484 STp->ps[i].last_block_valid = 0;
3485 }
3486 STp->partition = STp->new_partition = 0;
3487 STp->nbr_partitions = 1; /* Bad guess ?-) */
3488 STps->drv_block = STps->drv_file = 0;
3489 retval = 0;
3490 goto out;
3491 }
3492
3493 if (mtc.mt_op == MTSEEK) {
3494 i = set_location(STp, mtc.mt_count, STp->new_partition, 0);
3495 if (!STp->can_partitions)
3496 STp->ps[0].rw = ST_IDLE;
3497 retval = i;
3498 goto out;
3499 }
3500
3501 if (mtc.mt_op == MTUNLOAD || mtc.mt_op == MTOFFL) {
3502 retval = do_load_unload(STp, file, 0);
3503 goto out;
3504 }
3505
3506 if (mtc.mt_op == MTLOAD) {
3507 retval = do_load_unload(STp, file, max(1, mtc.mt_count));
3508 goto out;
3509 }
3510
3511 if (mtc.mt_op == MTLOCK || mtc.mt_op == MTUNLOCK) {
3512 retval = do_door_lock(STp, (mtc.mt_op == MTLOCK));
3513 goto out;
3514 }
3515
3516 if (STp->can_partitions && STp->ready == ST_READY &&
3517 (i = switch_partition(STp)) < 0) {
3518 retval = i;
3519 goto out;
3520 }
3521
3522 if (mtc.mt_op == MTCOMPRESSION)
3523 retval = st_compression(STp, (mtc.mt_count & 1));
3524 else
3525 retval = st_int_ioctl(STp, mtc.mt_op, mtc.mt_count);
3526 goto out;
3527 }
3528 if (!STm->defined) {
3529 retval = (-ENXIO);
3530 goto out;
3531 }
3532
3533 if ((i = flush_buffer(STp, 0)) < 0) {
3534 retval = i;
3535 goto out;
3536 }
3537 if (STp->can_partitions &&
3538 (i = switch_partition(STp)) < 0) {
3539 retval = i;
3540 goto out;
3541 }
3542
3543 if (cmd_type == _IOC_TYPE(MTIOCGET) && cmd_nr == _IOC_NR(MTIOCGET)) {
3544 struct mtget mt_status;
3545
3546 if (_IOC_SIZE(cmd_in) != sizeof(struct mtget)) {
3547 retval = (-EINVAL);
3548 goto out;
3549 }
3550
3551 mt_status.mt_type = STp->tape_type;
3552 mt_status.mt_dsreg =
3553 ((STp->block_size << MT_ST_BLKSIZE_SHIFT) & MT_ST_BLKSIZE_MASK) |
3554 ((STp->density << MT_ST_DENSITY_SHIFT) & MT_ST_DENSITY_MASK);
3555 mt_status.mt_blkno = STps->drv_block;
3556 mt_status.mt_fileno = STps->drv_file;
3557 if (STp->block_size != 0) {
3558 if (STps->rw == ST_WRITING)
3559 mt_status.mt_blkno +=
3560 (STp->buffer)->buffer_bytes / STp->block_size;
3561 else if (STps->rw == ST_READING)
3562 mt_status.mt_blkno -=
3563 ((STp->buffer)->buffer_bytes +
3564 STp->block_size - 1) / STp->block_size;
3565 }
3566
3567 mt_status.mt_gstat = 0;
3568 if (STp->drv_write_prot)
3569 mt_status.mt_gstat |= GMT_WR_PROT(0xffffffff);
3570 if (mt_status.mt_blkno == 0) {
3571 if (mt_status.mt_fileno == 0)
3572 mt_status.mt_gstat |= GMT_BOT(0xffffffff);
3573 else
3574 mt_status.mt_gstat |= GMT_EOF(0xffffffff);
3575 }
3576 mt_status.mt_erreg = (STp->recover_reg << MT_ST_SOFTERR_SHIFT);
3577 mt_status.mt_resid = STp->partition;
3578 if (STps->eof == ST_EOM_OK || STps->eof == ST_EOM_ERROR)
3579 mt_status.mt_gstat |= GMT_EOT(0xffffffff);
3580 else if (STps->eof >= ST_EOM_OK)
3581 mt_status.mt_gstat |= GMT_EOD(0xffffffff);
3582 if (STp->density == 1)
3583 mt_status.mt_gstat |= GMT_D_800(0xffffffff);
3584 else if (STp->density == 2)
3585 mt_status.mt_gstat |= GMT_D_1600(0xffffffff);
3586 else if (STp->density == 3)
3587 mt_status.mt_gstat |= GMT_D_6250(0xffffffff);
3588 if (STp->ready == ST_READY)
3589 mt_status.mt_gstat |= GMT_ONLINE(0xffffffff);
3590 if (STp->ready == ST_NO_TAPE)
3591 mt_status.mt_gstat |= GMT_DR_OPEN(0xffffffff);
3592 if (STps->at_sm)
3593 mt_status.mt_gstat |= GMT_SM(0xffffffff);
3594 if (STm->do_async_writes ||
3595 (STm->do_buffer_writes && STp->block_size != 0) ||
3596 STp->drv_buffer != 0)
3597 mt_status.mt_gstat |= GMT_IM_REP_EN(0xffffffff);
3598 if (STp->cleaning_req)
3599 mt_status.mt_gstat |= GMT_CLN(0xffffffff);
3600
3601 i = copy_to_user(p, &mt_status, sizeof(struct mtget));
3602 if (i) {
3603 retval = (-EFAULT);
3604 goto out;
3605 }
3606
3607 STp->recover_reg = 0; /* Clear after read */
3608 retval = 0;
3609 goto out;
3610 } /* End of MTIOCGET */
3611 if (cmd_type == _IOC_TYPE(MTIOCPOS) && cmd_nr == _IOC_NR(MTIOCPOS)) {
3612 struct mtpos mt_pos;
3613 if (_IOC_SIZE(cmd_in) != sizeof(struct mtpos)) {
3614 retval = (-EINVAL);
3615 goto out;
3616 }
3617 if ((i = get_location(STp, &blk, &bt, 0)) < 0) {
3618 retval = i;
3619 goto out;
3620 }
3621 mt_pos.mt_blkno = blk;
3622 i = copy_to_user(p, &mt_pos, sizeof(struct mtpos));
3623 if (i)
3624 retval = (-EFAULT);
3625 goto out;
3626 }
3627 mutex_unlock(&STp->lock);
3628 switch (cmd_in) {
3629 case SCSI_IOCTL_GET_IDLUN:
3630 case SCSI_IOCTL_GET_BUS_NUMBER:
3631 break;
3632 default:
3633 if ((cmd_in == SG_IO ||
3634 cmd_in == SCSI_IOCTL_SEND_COMMAND ||
3635 cmd_in == CDROM_SEND_PACKET) &&
3636 !capable(CAP_SYS_RAWIO))
3637 i = -EPERM;
3638 else
3639 i = scsi_cmd_ioctl(STp->disk->queue, STp->disk,
3640 file->f_mode, cmd_in, p);
3641 if (i != -ENOTTY)
3642 return i;
3643 break;
3644 }
3645 retval = scsi_ioctl(STp->device, cmd_in, p);
3646 if (!retval && cmd_in == SCSI_IOCTL_STOP_UNIT) { /* unload */
3647 STp->rew_at_close = 0;
3648 STp->ready = ST_NO_TAPE;
3649 }
3650 return retval;
3651
3652 out:
3653 mutex_unlock(&STp->lock);
3654 return retval;
3655 }
3656
3657 #ifdef CONFIG_COMPAT
3658 static long st_compat_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
3659 {
3660 struct scsi_tape *STp = file->private_data;
3661 struct scsi_device *sdev = STp->device;
3662 int ret = -ENOIOCTLCMD;
3663 if (sdev->host->hostt->compat_ioctl) {
3664
3665 ret = sdev->host->hostt->compat_ioctl(sdev, cmd, (void __user *)arg);
3666
3667 }
3668 return ret;
3669 }
3670 #endif
3671
3672 \f
3673
3674 /* Try to allocate a new tape buffer. Calling function must not hold
3675 dev_arr_lock. */
3676 static struct st_buffer *new_tape_buffer(int need_dma, int max_sg)
3677 {
3678 struct st_buffer *tb;
3679
3680 tb = kzalloc(sizeof(struct st_buffer), GFP_ATOMIC);
3681 if (!tb) {
3682 printk(KERN_NOTICE "st: Can't allocate new tape buffer.\n");
3683 return NULL;
3684 }
3685 tb->frp_segs = 0;
3686 tb->use_sg = max_sg;
3687 tb->dma = need_dma;
3688 tb->buffer_size = 0;
3689
3690 tb->reserved_pages = kzalloc(max_sg * sizeof(struct page *),
3691 GFP_ATOMIC);
3692 if (!tb->reserved_pages) {
3693 kfree(tb);
3694 return NULL;
3695 }
3696
3697 return tb;
3698 }
3699
3700
3701 /* Try to allocate enough space in the tape buffer */
3702 #define ST_MAX_ORDER 6
3703
3704 static int enlarge_buffer(struct st_buffer * STbuffer, int new_size, int need_dma)
3705 {
3706 int segs, nbr, max_segs, b_size, order, got;
3707 gfp_t priority;
3708
3709 if (new_size <= STbuffer->buffer_size)
3710 return 1;
3711
3712 if (STbuffer->buffer_size <= PAGE_SIZE)
3713 normalize_buffer(STbuffer); /* Avoid extra segment */
3714
3715 max_segs = STbuffer->use_sg;
3716 nbr = max_segs - STbuffer->frp_segs;
3717 if (nbr <= 0)
3718 return 0;
3719
3720 priority = GFP_KERNEL | __GFP_NOWARN;
3721 if (need_dma)
3722 priority |= GFP_DMA;
3723
3724 if (STbuffer->cleared)
3725 priority |= __GFP_ZERO;
3726
3727 if (STbuffer->frp_segs) {
3728 order = STbuffer->reserved_page_order;
3729 b_size = PAGE_SIZE << order;
3730 } else {
3731 for (b_size = PAGE_SIZE, order = 0;
3732 order < ST_MAX_ORDER &&
3733 max_segs * (PAGE_SIZE << order) < new_size;
3734 order++, b_size *= 2)
3735 ; /* empty */
3736 STbuffer->reserved_page_order = order;
3737 }
3738 if (max_segs * (PAGE_SIZE << order) < new_size) {
3739 if (order == ST_MAX_ORDER)
3740 return 0;
3741 normalize_buffer(STbuffer);
3742 return enlarge_buffer(STbuffer, new_size, need_dma);
3743 }
3744
3745 for (segs = STbuffer->frp_segs, got = STbuffer->buffer_size;
3746 segs < max_segs && got < new_size;) {
3747 struct page *page;
3748
3749 page = alloc_pages(priority, order);
3750 if (!page) {
3751 DEB(STbuffer->buffer_size = got);
3752 normalize_buffer(STbuffer);
3753 return 0;
3754 }
3755
3756 STbuffer->frp_segs += 1;
3757 got += b_size;
3758 STbuffer->buffer_size = got;
3759 STbuffer->reserved_pages[segs] = page;
3760 segs++;
3761 }
3762 STbuffer->b_data = page_address(STbuffer->reserved_pages[0]);
3763
3764 return 1;
3765 }
3766
3767
3768 /* Make sure that no data from previous user is in the internal buffer */
3769 static void clear_buffer(struct st_buffer * st_bp)
3770 {
3771 int i;
3772
3773 for (i=0; i < st_bp->frp_segs; i++)
3774 memset(page_address(st_bp->reserved_pages[i]), 0,
3775 PAGE_SIZE << st_bp->reserved_page_order);
3776 st_bp->cleared = 1;
3777 }
3778
3779
3780 /* Release the extra buffer */
3781 static void normalize_buffer(struct st_buffer * STbuffer)
3782 {
3783 int i, order = STbuffer->reserved_page_order;
3784
3785 for (i = 0; i < STbuffer->frp_segs; i++) {
3786 __free_pages(STbuffer->reserved_pages[i], order);
3787 STbuffer->buffer_size -= (PAGE_SIZE << order);
3788 }
3789 STbuffer->frp_segs = 0;
3790 STbuffer->sg_segs = 0;
3791 STbuffer->reserved_page_order = 0;
3792 STbuffer->map_data.offset = 0;
3793 }
3794
3795
3796 /* Move data from the user buffer to the tape buffer. Returns zero (success) or
3797 negative error code. */
3798 static int append_to_buffer(const char __user *ubp, struct st_buffer * st_bp, int do_count)
3799 {
3800 int i, cnt, res, offset;
3801 int length = PAGE_SIZE << st_bp->reserved_page_order;
3802
3803 for (i = 0, offset = st_bp->buffer_bytes;
3804 i < st_bp->frp_segs && offset >= length; i++)
3805 offset -= length;
3806 if (i == st_bp->frp_segs) { /* Should never happen */
3807 printk(KERN_WARNING "st: append_to_buffer offset overflow.\n");
3808 return (-EIO);
3809 }
3810 for (; i < st_bp->frp_segs && do_count > 0; i++) {
3811 struct page *page = st_bp->reserved_pages[i];
3812 cnt = length - offset < do_count ? length - offset : do_count;
3813 res = copy_from_user(page_address(page) + offset, ubp, cnt);
3814 if (res)
3815 return (-EFAULT);
3816 do_count -= cnt;
3817 st_bp->buffer_bytes += cnt;
3818 ubp += cnt;
3819 offset = 0;
3820 }
3821 if (do_count) /* Should never happen */
3822 return (-EIO);
3823
3824 return 0;
3825 }
3826
3827
3828 /* Move data from the tape buffer to the user buffer. Returns zero (success) or
3829 negative error code. */
3830 static int from_buffer(struct st_buffer * st_bp, char __user *ubp, int do_count)
3831 {
3832 int i, cnt, res, offset;
3833 int length = PAGE_SIZE << st_bp->reserved_page_order;
3834
3835 for (i = 0, offset = st_bp->read_pointer;
3836 i < st_bp->frp_segs && offset >= length; i++)
3837 offset -= length;
3838 if (i == st_bp->frp_segs) { /* Should never happen */
3839 printk(KERN_WARNING "st: from_buffer offset overflow.\n");
3840 return (-EIO);
3841 }
3842 for (; i < st_bp->frp_segs && do_count > 0; i++) {
3843 struct page *page = st_bp->reserved_pages[i];
3844 cnt = length - offset < do_count ? length - offset : do_count;
3845 res = copy_to_user(ubp, page_address(page) + offset, cnt);
3846 if (res)
3847 return (-EFAULT);
3848 do_count -= cnt;
3849 st_bp->buffer_bytes -= cnt;
3850 st_bp->read_pointer += cnt;
3851 ubp += cnt;
3852 offset = 0;
3853 }
3854 if (do_count) /* Should never happen */
3855 return (-EIO);
3856
3857 return 0;
3858 }
3859
3860
3861 /* Move data towards start of buffer */
3862 static void move_buffer_data(struct st_buffer * st_bp, int offset)
3863 {
3864 int src_seg, dst_seg, src_offset = 0, dst_offset;
3865 int count, total;
3866 int length = PAGE_SIZE << st_bp->reserved_page_order;
3867
3868 if (offset == 0)
3869 return;
3870
3871 total=st_bp->buffer_bytes - offset;
3872 for (src_seg=0; src_seg < st_bp->frp_segs; src_seg++) {
3873 src_offset = offset;
3874 if (src_offset < length)
3875 break;
3876 offset -= length;
3877 }
3878
3879 st_bp->buffer_bytes = st_bp->read_pointer = total;
3880 for (dst_seg=dst_offset=0; total > 0; ) {
3881 struct page *dpage = st_bp->reserved_pages[dst_seg];
3882 struct page *spage = st_bp->reserved_pages[src_seg];
3883
3884 count = min(length - dst_offset, length - src_offset);
3885 memmove(page_address(dpage) + dst_offset,
3886 page_address(spage) + src_offset, count);
3887 src_offset += count;
3888 if (src_offset >= length) {
3889 src_seg++;
3890 src_offset = 0;
3891 }
3892 dst_offset += count;
3893 if (dst_offset >= length) {
3894 dst_seg++;
3895 dst_offset = 0;
3896 }
3897 total -= count;
3898 }
3899 }
3900
3901 /* Validate the options from command line or module parameters */
3902 static void validate_options(void)
3903 {
3904 if (buffer_kbs > 0)
3905 st_fixed_buffer_size = buffer_kbs * ST_KILOBYTE;
3906 if (max_sg_segs >= ST_FIRST_SG)
3907 st_max_sg_segs = max_sg_segs;
3908 }
3909
3910 #ifndef MODULE
3911 /* Set the boot options. Syntax is defined in Documenation/scsi/st.txt.
3912 */
3913 static int __init st_setup(char *str)
3914 {
3915 int i, len, ints[5];
3916 char *stp;
3917
3918 stp = get_options(str, ARRAY_SIZE(ints), ints);
3919
3920 if (ints[0] > 0) {
3921 for (i = 0; i < ints[0] && i < ARRAY_SIZE(parms); i++)
3922 if (parms[i].val)
3923 *parms[i].val = ints[i + 1];
3924 } else {
3925 while (stp != NULL) {
3926 for (i = 0; i < ARRAY_SIZE(parms); i++) {
3927 len = strlen(parms[i].name);
3928 if (!strncmp(stp, parms[i].name, len) &&
3929 (*(stp + len) == ':' || *(stp + len) == '=')) {
3930 if (parms[i].val)
3931 *parms[i].val =
3932 simple_strtoul(stp + len + 1, NULL, 0);
3933 else
3934 printk(KERN_WARNING "st: Obsolete parameter %s\n",
3935 parms[i].name);
3936 break;
3937 }
3938 }
3939 if (i >= ARRAY_SIZE(parms))
3940 printk(KERN_WARNING "st: invalid parameter in '%s'\n",
3941 stp);
3942 stp = strchr(stp, ',');
3943 if (stp)
3944 stp++;
3945 }
3946 }
3947
3948 validate_options();
3949
3950 return 1;
3951 }
3952
3953 __setup("st=", st_setup);
3954
3955 #endif
3956
3957 static const struct file_operations st_fops =
3958 {
3959 .owner = THIS_MODULE,
3960 .read = st_read,
3961 .write = st_write,
3962 .unlocked_ioctl = st_ioctl,
3963 #ifdef CONFIG_COMPAT
3964 .compat_ioctl = st_compat_ioctl,
3965 #endif
3966 .open = st_open,
3967 .flush = st_flush,
3968 .release = st_release,
3969 .llseek = noop_llseek,
3970 };
3971
3972 static int st_probe(struct device *dev)
3973 {
3974 struct scsi_device *SDp = to_scsi_device(dev);
3975 struct gendisk *disk = NULL;
3976 struct cdev *cdev = NULL;
3977 struct scsi_tape *tpnt = NULL;
3978 struct st_modedef *STm;
3979 struct st_partstat *STps;
3980 struct st_buffer *buffer;
3981 int i, j, mode, dev_num, error;
3982 char *stp;
3983
3984 if (SDp->type != TYPE_TAPE)
3985 return -ENODEV;
3986 if ((stp = st_incompatible(SDp))) {
3987 sdev_printk(KERN_INFO, SDp, "Found incompatible tape\n");
3988 printk(KERN_INFO "st: The suggested driver is %s.\n", stp);
3989 return -ENODEV;
3990 }
3991
3992 i = queue_max_segments(SDp->request_queue);
3993 if (st_max_sg_segs < i)
3994 i = st_max_sg_segs;
3995 buffer = new_tape_buffer((SDp->host)->unchecked_isa_dma, i);
3996 if (buffer == NULL) {
3997 printk(KERN_ERR
3998 "st: Can't allocate new tape buffer. Device not attached.\n");
3999 goto out;
4000 }
4001
4002 disk = alloc_disk(1);
4003 if (!disk) {
4004 printk(KERN_ERR "st: out of memory. Device not attached.\n");
4005 goto out_buffer_free;
4006 }
4007
4008 write_lock(&st_dev_arr_lock);
4009 if (st_nr_dev >= st_dev_max) {
4010 struct scsi_tape **tmp_da;
4011 int tmp_dev_max;
4012
4013 tmp_dev_max = max(st_nr_dev * 2, 8);
4014 if (tmp_dev_max > ST_MAX_TAPES)
4015 tmp_dev_max = ST_MAX_TAPES;
4016 if (tmp_dev_max <= st_nr_dev) {
4017 write_unlock(&st_dev_arr_lock);
4018 printk(KERN_ERR "st: Too many tape devices (max. %d).\n",
4019 ST_MAX_TAPES);
4020 goto out_put_disk;
4021 }
4022
4023 tmp_da = kzalloc(tmp_dev_max * sizeof(struct scsi_tape *), GFP_ATOMIC);
4024 if (tmp_da == NULL) {
4025 write_unlock(&st_dev_arr_lock);
4026 printk(KERN_ERR "st: Can't extend device array.\n");
4027 goto out_put_disk;
4028 }
4029
4030 if (scsi_tapes != NULL) {
4031 memcpy(tmp_da, scsi_tapes,
4032 st_dev_max * sizeof(struct scsi_tape *));
4033 kfree(scsi_tapes);
4034 }
4035 scsi_tapes = tmp_da;
4036
4037 st_dev_max = tmp_dev_max;
4038 }
4039
4040 for (i = 0; i < st_dev_max; i++)
4041 if (scsi_tapes[i] == NULL)
4042 break;
4043 if (i >= st_dev_max)
4044 panic("scsi_devices corrupt (st)");
4045
4046 tpnt = kzalloc(sizeof(struct scsi_tape), GFP_ATOMIC);
4047 if (tpnt == NULL) {
4048 write_unlock(&st_dev_arr_lock);
4049 printk(KERN_ERR "st: Can't allocate device descriptor.\n");
4050 goto out_put_disk;
4051 }
4052 kref_init(&tpnt->kref);
4053 tpnt->disk = disk;
4054 sprintf(disk->disk_name, "st%d", i);
4055 disk->private_data = &tpnt->driver;
4056 disk->queue = SDp->request_queue;
4057 tpnt->driver = &st_template;
4058 scsi_tapes[i] = tpnt;
4059 dev_num = i;
4060
4061 tpnt->device = SDp;
4062 if (SDp->scsi_level <= 2)
4063 tpnt->tape_type = MT_ISSCSI1;
4064 else
4065 tpnt->tape_type = MT_ISSCSI2;
4066
4067 tpnt->buffer = buffer;
4068 tpnt->buffer->last_SRpnt = NULL;
4069
4070 tpnt->inited = 0;
4071 tpnt->dirty = 0;
4072 tpnt->in_use = 0;
4073 tpnt->drv_buffer = 1; /* Try buffering if no mode sense */
4074 tpnt->restr_dma = (SDp->host)->unchecked_isa_dma;
4075 tpnt->use_pf = (SDp->scsi_level >= SCSI_2);
4076 tpnt->density = 0;
4077 tpnt->do_auto_lock = ST_AUTO_LOCK;
4078 tpnt->can_bsr = (SDp->scsi_level > 2 ? 1 : ST_IN_FILE_POS); /* BSR mandatory in SCSI3 */
4079 tpnt->can_partitions = 0;
4080 tpnt->two_fm = ST_TWO_FM;
4081 tpnt->fast_mteom = ST_FAST_MTEOM;
4082 tpnt->scsi2_logical = ST_SCSI2LOGICAL;
4083 tpnt->sili = ST_SILI;
4084 tpnt->immediate = ST_NOWAIT;
4085 tpnt->default_drvbuffer = 0xff; /* No forced buffering */
4086 tpnt->partition = 0;
4087 tpnt->new_partition = 0;
4088 tpnt->nbr_partitions = 0;
4089 blk_queue_rq_timeout(tpnt->device->request_queue, ST_TIMEOUT);
4090 tpnt->long_timeout = ST_LONG_TIMEOUT;
4091 tpnt->try_dio = try_direct_io && !SDp->host->unchecked_isa_dma;
4092
4093 for (i = 0; i < ST_NBR_MODES; i++) {
4094 STm = &(tpnt->modes[i]);
4095 STm->defined = 0;
4096 STm->sysv = ST_SYSV;
4097 STm->defaults_for_writes = 0;
4098 STm->do_async_writes = ST_ASYNC_WRITES;
4099 STm->do_buffer_writes = ST_BUFFER_WRITES;
4100 STm->do_read_ahead = ST_READ_AHEAD;
4101 STm->default_compression = ST_DONT_TOUCH;
4102 STm->default_blksize = (-1); /* No forced size */
4103 STm->default_density = (-1); /* No forced density */
4104 }
4105
4106 for (i = 0; i < ST_NBR_PARTITIONS; i++) {
4107 STps = &(tpnt->ps[i]);
4108 STps->rw = ST_IDLE;
4109 STps->eof = ST_NOEOF;
4110 STps->at_sm = 0;
4111 STps->last_block_valid = 0;
4112 STps->drv_block = (-1);
4113 STps->drv_file = (-1);
4114 }
4115
4116 tpnt->current_mode = 0;
4117 tpnt->modes[0].defined = 1;
4118
4119 tpnt->density_changed = tpnt->compression_changed =
4120 tpnt->blksize_changed = 0;
4121 mutex_init(&tpnt->lock);
4122
4123 st_nr_dev++;
4124 write_unlock(&st_dev_arr_lock);
4125
4126 for (mode = 0; mode < ST_NBR_MODES; ++mode) {
4127 STm = &(tpnt->modes[mode]);
4128 for (j=0; j < 2; j++) {
4129 cdev = cdev_alloc();
4130 if (!cdev) {
4131 printk(KERN_ERR
4132 "st%d: out of memory. Device not attached.\n",
4133 dev_num);
4134 goto out_free_tape;
4135 }
4136 cdev->owner = THIS_MODULE;
4137 cdev->ops = &st_fops;
4138
4139 error = cdev_add(cdev,
4140 MKDEV(SCSI_TAPE_MAJOR, TAPE_MINOR(dev_num, mode, j)),
4141 1);
4142 if (error) {
4143 printk(KERN_ERR "st%d: Can't add %s-rewind mode %d\n",
4144 dev_num, j ? "non" : "auto", mode);
4145 printk(KERN_ERR "st%d: Device not attached.\n", dev_num);
4146 goto out_free_tape;
4147 }
4148 STm->cdevs[j] = cdev;
4149
4150 }
4151 error = do_create_class_files(tpnt, dev_num, mode);
4152 if (error)
4153 goto out_free_tape;
4154 }
4155
4156 sdev_printk(KERN_NOTICE, SDp,
4157 "Attached scsi tape %s\n", tape_name(tpnt));
4158 sdev_printk(KERN_INFO, SDp, "%s: try direct i/o: %s (alignment %d B)\n",
4159 tape_name(tpnt), tpnt->try_dio ? "yes" : "no",
4160 queue_dma_alignment(SDp->request_queue) + 1);
4161
4162 return 0;
4163
4164 out_free_tape:
4165 for (mode=0; mode < ST_NBR_MODES; mode++) {
4166 STm = &(tpnt->modes[mode]);
4167 sysfs_remove_link(&tpnt->device->sdev_gendev.kobj,
4168 "tape");
4169 for (j=0; j < 2; j++) {
4170 if (STm->cdevs[j]) {
4171 if (cdev == STm->cdevs[j])
4172 cdev = NULL;
4173 device_destroy(st_sysfs_class,
4174 MKDEV(SCSI_TAPE_MAJOR,
4175 TAPE_MINOR(i, mode, j)));
4176 cdev_del(STm->cdevs[j]);
4177 }
4178 }
4179 }
4180 if (cdev)
4181 cdev_del(cdev);
4182 write_lock(&st_dev_arr_lock);
4183 scsi_tapes[dev_num] = NULL;
4184 st_nr_dev--;
4185 write_unlock(&st_dev_arr_lock);
4186 out_put_disk:
4187 put_disk(disk);
4188 kfree(tpnt);
4189 out_buffer_free:
4190 kfree(buffer);
4191 out:
4192 return -ENODEV;
4193 };
4194
4195
4196 static int st_remove(struct device *dev)
4197 {
4198 struct scsi_device *SDp = to_scsi_device(dev);
4199 struct scsi_tape *tpnt;
4200 int i, j, mode;
4201
4202 write_lock(&st_dev_arr_lock);
4203 for (i = 0; i < st_dev_max; i++) {
4204 tpnt = scsi_tapes[i];
4205 if (tpnt != NULL && tpnt->device == SDp) {
4206 scsi_tapes[i] = NULL;
4207 st_nr_dev--;
4208 write_unlock(&st_dev_arr_lock);
4209 sysfs_remove_link(&tpnt->device->sdev_gendev.kobj,
4210 "tape");
4211 for (mode = 0; mode < ST_NBR_MODES; ++mode) {
4212 for (j=0; j < 2; j++) {
4213 device_destroy(st_sysfs_class,
4214 MKDEV(SCSI_TAPE_MAJOR,
4215 TAPE_MINOR(i, mode, j)));
4216 cdev_del(tpnt->modes[mode].cdevs[j]);
4217 tpnt->modes[mode].cdevs[j] = NULL;
4218 }
4219 }
4220
4221 mutex_lock(&st_ref_mutex);
4222 kref_put(&tpnt->kref, scsi_tape_release);
4223 mutex_unlock(&st_ref_mutex);
4224 return 0;
4225 }
4226 }
4227
4228 write_unlock(&st_dev_arr_lock);
4229 return 0;
4230 }
4231
4232 /**
4233 * scsi_tape_release - Called to free the Scsi_Tape structure
4234 * @kref: pointer to embedded kref
4235 *
4236 * st_ref_mutex must be held entering this routine. Because it is
4237 * called on last put, you should always use the scsi_tape_get()
4238 * scsi_tape_put() helpers which manipulate the semaphore directly
4239 * and never do a direct kref_put().
4240 **/
4241 static void scsi_tape_release(struct kref *kref)
4242 {
4243 struct scsi_tape *tpnt = to_scsi_tape(kref);
4244 struct gendisk *disk = tpnt->disk;
4245
4246 tpnt->device = NULL;
4247
4248 if (tpnt->buffer) {
4249 normalize_buffer(tpnt->buffer);
4250 kfree(tpnt->buffer->reserved_pages);
4251 kfree(tpnt->buffer);
4252 }
4253
4254 disk->private_data = NULL;
4255 put_disk(disk);
4256 kfree(tpnt);
4257 return;
4258 }
4259
4260 static int __init init_st(void)
4261 {
4262 int err;
4263
4264 validate_options();
4265
4266 printk(KERN_INFO "st: Version %s, fixed bufsize %d, s/g segs %d\n",
4267 verstr, st_fixed_buffer_size, st_max_sg_segs);
4268
4269 st_sysfs_class = class_create(THIS_MODULE, "scsi_tape");
4270 if (IS_ERR(st_sysfs_class)) {
4271 printk(KERN_ERR "Unable create sysfs class for SCSI tapes\n");
4272 return PTR_ERR(st_sysfs_class);
4273 }
4274
4275 err = register_chrdev_region(MKDEV(SCSI_TAPE_MAJOR, 0),
4276 ST_MAX_TAPE_ENTRIES, "st");
4277 if (err) {
4278 printk(KERN_ERR "Unable to get major %d for SCSI tapes\n",
4279 SCSI_TAPE_MAJOR);
4280 goto err_class;
4281 }
4282
4283 err = scsi_register_driver(&st_template.gendrv);
4284 if (err)
4285 goto err_chrdev;
4286
4287 err = do_create_sysfs_files();
4288 if (err)
4289 goto err_scsidrv;
4290
4291 return 0;
4292
4293 err_scsidrv:
4294 scsi_unregister_driver(&st_template.gendrv);
4295 err_chrdev:
4296 unregister_chrdev_region(MKDEV(SCSI_TAPE_MAJOR, 0),
4297 ST_MAX_TAPE_ENTRIES);
4298 err_class:
4299 class_destroy(st_sysfs_class);
4300 return err;
4301 }
4302
4303 static void __exit exit_st(void)
4304 {
4305 do_remove_sysfs_files();
4306 scsi_unregister_driver(&st_template.gendrv);
4307 unregister_chrdev_region(MKDEV(SCSI_TAPE_MAJOR, 0),
4308 ST_MAX_TAPE_ENTRIES);
4309 class_destroy(st_sysfs_class);
4310 kfree(scsi_tapes);
4311 printk(KERN_INFO "st: Unloaded.\n");
4312 }
4313
4314 module_init(init_st);
4315 module_exit(exit_st);
4316
4317
4318 /* The sysfs driver interface. Read-only at the moment */
4319 static ssize_t st_try_direct_io_show(struct device_driver *ddp, char *buf)
4320 {
4321 return snprintf(buf, PAGE_SIZE, "%d\n", try_direct_io);
4322 }
4323 static DRIVER_ATTR(try_direct_io, S_IRUGO, st_try_direct_io_show, NULL);
4324
4325 static ssize_t st_fixed_buffer_size_show(struct device_driver *ddp, char *buf)
4326 {
4327 return snprintf(buf, PAGE_SIZE, "%d\n", st_fixed_buffer_size);
4328 }
4329 static DRIVER_ATTR(fixed_buffer_size, S_IRUGO, st_fixed_buffer_size_show, NULL);
4330
4331 static ssize_t st_max_sg_segs_show(struct device_driver *ddp, char *buf)
4332 {
4333 return snprintf(buf, PAGE_SIZE, "%d\n", st_max_sg_segs);
4334 }
4335 static DRIVER_ATTR(max_sg_segs, S_IRUGO, st_max_sg_segs_show, NULL);
4336
4337 static ssize_t st_version_show(struct device_driver *ddd, char *buf)
4338 {
4339 return snprintf(buf, PAGE_SIZE, "[%s]\n", verstr);
4340 }
4341 static DRIVER_ATTR(version, S_IRUGO, st_version_show, NULL);
4342
4343 static int do_create_sysfs_files(void)
4344 {
4345 struct device_driver *sysfs = &st_template.gendrv;
4346 int err;
4347
4348 err = driver_create_file(sysfs, &driver_attr_try_direct_io);
4349 if (err)
4350 return err;
4351 err = driver_create_file(sysfs, &driver_attr_fixed_buffer_size);
4352 if (err)
4353 goto err_try_direct_io;
4354 err = driver_create_file(sysfs, &driver_attr_max_sg_segs);
4355 if (err)
4356 goto err_attr_fixed_buf;
4357 err = driver_create_file(sysfs, &driver_attr_version);
4358 if (err)
4359 goto err_attr_max_sg;
4360
4361 return 0;
4362
4363 err_attr_max_sg:
4364 driver_remove_file(sysfs, &driver_attr_max_sg_segs);
4365 err_attr_fixed_buf:
4366 driver_remove_file(sysfs, &driver_attr_fixed_buffer_size);
4367 err_try_direct_io:
4368 driver_remove_file(sysfs, &driver_attr_try_direct_io);
4369 return err;
4370 }
4371
4372 static void do_remove_sysfs_files(void)
4373 {
4374 struct device_driver *sysfs = &st_template.gendrv;
4375
4376 driver_remove_file(sysfs, &driver_attr_version);
4377 driver_remove_file(sysfs, &driver_attr_max_sg_segs);
4378 driver_remove_file(sysfs, &driver_attr_fixed_buffer_size);
4379 driver_remove_file(sysfs, &driver_attr_try_direct_io);
4380 }
4381
4382
4383 /* The sysfs simple class interface */
4384 static ssize_t
4385 st_defined_show(struct device *dev, struct device_attribute *attr, char *buf)
4386 {
4387 struct st_modedef *STm = dev_get_drvdata(dev);
4388 ssize_t l = 0;
4389
4390 l = snprintf(buf, PAGE_SIZE, "%d\n", STm->defined);
4391 return l;
4392 }
4393
4394 DEVICE_ATTR(defined, S_IRUGO, st_defined_show, NULL);
4395
4396 static ssize_t
4397 st_defblk_show(struct device *dev, struct device_attribute *attr, char *buf)
4398 {
4399 struct st_modedef *STm = dev_get_drvdata(dev);
4400 ssize_t l = 0;
4401
4402 l = snprintf(buf, PAGE_SIZE, "%d\n", STm->default_blksize);
4403 return l;
4404 }
4405
4406 DEVICE_ATTR(default_blksize, S_IRUGO, st_defblk_show, NULL);
4407
4408 static ssize_t
4409 st_defdensity_show(struct device *dev, struct device_attribute *attr, char *buf)
4410 {
4411 struct st_modedef *STm = dev_get_drvdata(dev);
4412 ssize_t l = 0;
4413 char *fmt;
4414
4415 fmt = STm->default_density >= 0 ? "0x%02x\n" : "%d\n";
4416 l = snprintf(buf, PAGE_SIZE, fmt, STm->default_density);
4417 return l;
4418 }
4419
4420 DEVICE_ATTR(default_density, S_IRUGO, st_defdensity_show, NULL);
4421
4422 static ssize_t
4423 st_defcompression_show(struct device *dev, struct device_attribute *attr,
4424 char *buf)
4425 {
4426 struct st_modedef *STm = dev_get_drvdata(dev);
4427 ssize_t l = 0;
4428
4429 l = snprintf(buf, PAGE_SIZE, "%d\n", STm->default_compression - 1);
4430 return l;
4431 }
4432
4433 DEVICE_ATTR(default_compression, S_IRUGO, st_defcompression_show, NULL);
4434
4435 static ssize_t
4436 st_options_show(struct device *dev, struct device_attribute *attr, char *buf)
4437 {
4438 struct st_modedef *STm = dev_get_drvdata(dev);
4439 struct scsi_tape *STp;
4440 int i, j, options;
4441 ssize_t l = 0;
4442
4443 for (i=0; i < st_dev_max; i++) {
4444 for (j=0; j < ST_NBR_MODES; j++)
4445 if (&scsi_tapes[i]->modes[j] == STm)
4446 break;
4447 if (j < ST_NBR_MODES)
4448 break;
4449 }
4450 if (i == st_dev_max)
4451 return 0; /* should never happen */
4452
4453 STp = scsi_tapes[i];
4454
4455 options = STm->do_buffer_writes ? MT_ST_BUFFER_WRITES : 0;
4456 options |= STm->do_async_writes ? MT_ST_ASYNC_WRITES : 0;
4457 options |= STm->do_read_ahead ? MT_ST_READ_AHEAD : 0;
4458 DEB( options |= debugging ? MT_ST_DEBUGGING : 0 );
4459 options |= STp->two_fm ? MT_ST_TWO_FM : 0;
4460 options |= STp->fast_mteom ? MT_ST_FAST_MTEOM : 0;
4461 options |= STm->defaults_for_writes ? MT_ST_DEF_WRITES : 0;
4462 options |= STp->can_bsr ? MT_ST_CAN_BSR : 0;
4463 options |= STp->omit_blklims ? MT_ST_NO_BLKLIMS : 0;
4464 options |= STp->can_partitions ? MT_ST_CAN_PARTITIONS : 0;
4465 options |= STp->scsi2_logical ? MT_ST_SCSI2LOGICAL : 0;
4466 options |= STm->sysv ? MT_ST_SYSV : 0;
4467 options |= STp->immediate ? MT_ST_NOWAIT : 0;
4468 options |= STp->sili ? MT_ST_SILI : 0;
4469
4470 l = snprintf(buf, PAGE_SIZE, "0x%08x\n", options);
4471 return l;
4472 }
4473
4474 DEVICE_ATTR(options, S_IRUGO, st_options_show, NULL);
4475
4476 static int do_create_class_files(struct scsi_tape *STp, int dev_num, int mode)
4477 {
4478 int i, rew, error;
4479 char name[10];
4480 struct device *st_class_member;
4481
4482 for (rew=0; rew < 2; rew++) {
4483 /* Make sure that the minor numbers corresponding to the four
4484 first modes always get the same names */
4485 i = mode << (4 - ST_NBR_MODE_BITS);
4486 snprintf(name, 10, "%s%s%s", rew ? "n" : "",
4487 STp->disk->disk_name, st_formats[i]);
4488 st_class_member =
4489 device_create(st_sysfs_class, &STp->device->sdev_gendev,
4490 MKDEV(SCSI_TAPE_MAJOR,
4491 TAPE_MINOR(dev_num, mode, rew)),
4492 &STp->modes[mode], "%s", name);
4493 if (IS_ERR(st_class_member)) {
4494 printk(KERN_WARNING "st%d: device_create failed\n",
4495 dev_num);
4496 error = PTR_ERR(st_class_member);
4497 goto out;
4498 }
4499
4500 error = device_create_file(st_class_member,
4501 &dev_attr_defined);
4502 if (error) goto out;
4503 error = device_create_file(st_class_member,
4504 &dev_attr_default_blksize);
4505 if (error) goto out;
4506 error = device_create_file(st_class_member,
4507 &dev_attr_default_density);
4508 if (error) goto out;
4509 error = device_create_file(st_class_member,
4510 &dev_attr_default_compression);
4511 if (error) goto out;
4512 error = device_create_file(st_class_member,
4513 &dev_attr_options);
4514 if (error) goto out;
4515
4516 if (mode == 0 && rew == 0) {
4517 error = sysfs_create_link(&STp->device->sdev_gendev.kobj,
4518 &st_class_member->kobj,
4519 "tape");
4520 if (error) {
4521 printk(KERN_ERR
4522 "st%d: Can't create sysfs link from SCSI device.\n",
4523 dev_num);
4524 goto out;
4525 }
4526 }
4527 }
4528
4529 return 0;
4530
4531 out:
4532 return error;
4533 }
4534
4535 /* The following functions may be useful for a larger audience. */
4536 static int sgl_map_user_pages(struct st_buffer *STbp,
4537 const unsigned int max_pages, unsigned long uaddr,
4538 size_t count, int rw)
4539 {
4540 unsigned long end = (uaddr + count + PAGE_SIZE - 1) >> PAGE_SHIFT;
4541 unsigned long start = uaddr >> PAGE_SHIFT;
4542 const int nr_pages = end - start;
4543 int res, i, j;
4544 struct page **pages;
4545 struct rq_map_data *mdata = &STbp->map_data;
4546
4547 /* User attempted Overflow! */
4548 if ((uaddr + count) < uaddr)
4549 return -EINVAL;
4550
4551 /* Too big */
4552 if (nr_pages > max_pages)
4553 return -ENOMEM;
4554
4555 /* Hmm? */
4556 if (count == 0)
4557 return 0;
4558
4559 if ((pages = kmalloc(max_pages * sizeof(*pages), GFP_KERNEL)) == NULL)
4560 return -ENOMEM;
4561
4562 /* Try to fault in all of the necessary pages */
4563 down_read(&current->mm->mmap_sem);
4564 /* rw==READ means read from drive, write into memory area */
4565 res = get_user_pages(
4566 current,
4567 current->mm,
4568 uaddr,
4569 nr_pages,
4570 rw == READ,
4571 0, /* don't force */
4572 pages,
4573 NULL);
4574 up_read(&current->mm->mmap_sem);
4575
4576 /* Errors and no page mapped should return here */
4577 if (res < nr_pages)
4578 goto out_unmap;
4579
4580 for (i=0; i < nr_pages; i++) {
4581 /* FIXME: flush superflous for rw==READ,
4582 * probably wrong function for rw==WRITE
4583 */
4584 flush_dcache_page(pages[i]);
4585 }
4586
4587 mdata->offset = uaddr & ~PAGE_MASK;
4588 STbp->mapped_pages = pages;
4589
4590 return nr_pages;
4591 out_unmap:
4592 if (res > 0) {
4593 for (j=0; j < res; j++)
4594 page_cache_release(pages[j]);
4595 res = 0;
4596 }
4597 kfree(pages);
4598 return res;
4599 }
4600
4601
4602 /* And unmap them... */
4603 static int sgl_unmap_user_pages(struct st_buffer *STbp,
4604 const unsigned int nr_pages, int dirtied)
4605 {
4606 int i;
4607
4608 for (i=0; i < nr_pages; i++) {
4609 struct page *page = STbp->mapped_pages[i];
4610
4611 if (dirtied)
4612 SetPageDirty(page);
4613 /* FIXME: cache flush missing for rw==READ
4614 * FIXME: call the correct reference counting function
4615 */
4616 page_cache_release(page);
4617 }
4618 kfree(STbp->mapped_pages);
4619 STbp->mapped_pages = NULL;
4620
4621 return 0;
4622 }
Linux Btrfs Development