1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3 SCSI Tape Driver for Linux version 1.1 and newer. See the accompanying
4 file Documentation/scsi/st.txt for more information.
5
6 History:
7 Rewritten from Dwayne Forsyth's SCSI tape driver by Kai Makisara.
8 Contribution and ideas from several people including (in alphabetical
9 order) Klaus Ehrenfried, Eugene Exarevsky, Eric Lee Green, Wolfgang Denk,
10 Steve Hirsch, Andreas Koppenh"ofer, Michael Leodolter, Eyal Lebedinsky,
11 Michael Schaefer, J"org Weule, and Eric Youngdale.
12
13 Copyright 1992 - 2016 Kai Makisara
14 email Kai.Makisara@kolumbus.fi
15
16 Some small formal changes - aeb, 950809
17
18 Last modified: 18-JAN-1998 Richard Gooch <rgooch@atnf.csiro.au> Devfs support
19 */
20
21 static const char *verstr = "20160209";
22
23 #include <linux/module.h>
24
25 #include <linux/fs.h>
26 #include <linux/kernel.h>
27 #include <linux/sched/signal.h>
28 #include <linux/mm.h>
29 #include <linux/init.h>
30 #include <linux/string.h>
31 #include <linux/slab.h>
32 #include <linux/errno.h>
33 #include <linux/mtio.h>
34 #include <linux/cdrom.h>
35 #include <linux/ioctl.h>
36 #include <linux/fcntl.h>
37 #include <linux/spinlock.h>
38 #include <linux/blkdev.h>
39 #include <linux/moduleparam.h>
40 #include <linux/cdev.h>
41 #include <linux/idr.h>
42 #include <linux/delay.h>
43 #include <linux/mutex.h>
44
45 #include <linux/uaccess.h>
46 #include <asm/dma.h>
47
48 #include <scsi/scsi.h>
49 #include <scsi/scsi_dbg.h>
50 #include <scsi/scsi_device.h>
51 #include <scsi/scsi_driver.h>
52 #include <scsi/scsi_eh.h>
53 #include <scsi/scsi_host.h>
54 #include <scsi/scsi_ioctl.h>
55 #include <scsi/sg.h>
56
57
58 /* The driver prints some debugging information on the console if DEBUG
59 is defined and non-zero. */
60 #define DEBUG 1
61 #define NO_DEBUG 0
62
63 #define ST_DEB_MSG KERN_NOTICE
64 #if DEBUG
65 /* The message level for the debug messages is currently set to KERN_NOTICE
66 so that people can easily see the messages. Later when the debugging messages
67 in the drivers are more widely classified, this may be changed to KERN_DEBUG. */
68 #define DEB(a) a
69 #define DEBC(a) if (debugging) { a ; }
70 #else
71 #define DEB(a)
72 #define DEBC(a)
73 #endif
74
75 #define ST_KILOBYTE 1024
76
77 #include "st_options.h"
78 #include "st.h"
79
80 static int buffer_kbs;
81 static int max_sg_segs;
82 static int try_direct_io = TRY_DIRECT_IO;
83 static int try_rdio = 1;
84 static int try_wdio = 1;
85 static int debug_flag;
86
87 static struct class st_sysfs_class;
88 static const struct attribute_group *st_dev_groups[];
89 static const struct attribute_group *st_drv_groups[];
90
91 MODULE_AUTHOR("Kai Makisara");
92 MODULE_DESCRIPTION("SCSI tape (st) driver");
93 MODULE_LICENSE("GPL");
94 MODULE_ALIAS_CHARDEV_MAJOR(SCSI_TAPE_MAJOR);
95 MODULE_ALIAS_SCSI_DEVICE(TYPE_TAPE);
96
97 /* Set 'perm' (4th argument) to 0 to disable module_param's definition
98 * of sysfs parameters (which module_param doesn't yet support).
99 * Sysfs parameters defined explicitly later.
100 */
101 module_param_named(buffer_kbs, buffer_kbs, int, 0);
102 MODULE_PARM_DESC(buffer_kbs, "Default driver buffer size for fixed block mode (KB; 32)");
103 module_param_named(max_sg_segs, max_sg_segs, int, 0);
104 MODULE_PARM_DESC(max_sg_segs, "Maximum number of scatter/gather segments to use (256)");
105 module_param_named(try_direct_io, try_direct_io, int, 0);
106 MODULE_PARM_DESC(try_direct_io, "Try direct I/O between user buffer and tape drive (1)");
107 module_param_named(debug_flag, debug_flag, int, 0);
108 MODULE_PARM_DESC(debug_flag, "Enable DEBUG, same as setting debugging=1");
109
110
111 /* Extra parameters for testing */
112 module_param_named(try_rdio, try_rdio, int, 0);
113 MODULE_PARM_DESC(try_rdio, "Try direct read i/o when possible");
114 module_param_named(try_wdio, try_wdio, int, 0);
115 MODULE_PARM_DESC(try_wdio, "Try direct write i/o when possible");
116
117 #ifndef MODULE
118 static int write_threshold_kbs; /* retained for compatibility */
119 static struct st_dev_parm {
120 char *name;
121 int *val;
122 } parms[] __initdata = {
123 {
124 "buffer_kbs", &buffer_kbs
125 },
126 { /* Retained for compatibility with 2.4 */
127 "write_threshold_kbs", &write_threshold_kbs
128 },
129 {
130 "max_sg_segs", NULL
131 },
132 {
133 "try_direct_io", &try_direct_io
134 },
135 {
136 "debug_flag", &debug_flag
137 }
138 };
139 #endif
140
141 /* Restrict the number of modes so that names for all are assigned */
142 #if ST_NBR_MODES > 16
143 #error "Maximum number of modes is 16"
144 #endif
145 /* Bit reversed order to get same names for same minors with all
146 mode counts */
147 static const char *st_formats[] = {
148 "", "r", "k", "s", "l", "t", "o", "u",
149 "m", "v", "p", "x", "a", "y", "q", "z"};
150
151 /* The default definitions have been moved to st_options.h */
152
153 #define ST_FIXED_BUFFER_SIZE (ST_FIXED_BUFFER_BLOCKS * ST_KILOBYTE)
154
155 /* The buffer size should fit into the 24 bits for length in the
156 6-byte SCSI read and write commands. */
157 #if ST_FIXED_BUFFER_SIZE >= (2 << 24 - 1)
158 #error "Buffer size should not exceed (2 << 24 - 1) bytes!"
159 #endif
160
161 static int debugging = DEBUG;
162
163 #define MAX_RETRIES 0
164 #define MAX_WRITE_RETRIES 0
165 #define MAX_READY_RETRIES 0
166 #define NO_TAPE NOT_READY
167
168 #define ST_TIMEOUT (900 * HZ)
169 #define ST_LONG_TIMEOUT (14000 * HZ)
170
171 /* Remove mode bits and auto-rewind bit (7) */
172 #define TAPE_NR(x) ( ((iminor(x) & ~255) >> (ST_NBR_MODE_BITS + 1)) | \
173 (iminor(x) & ((1 << ST_MODE_SHIFT)-1)))
174 #define TAPE_MODE(x) ((iminor(x) & ST_MODE_MASK) >> ST_MODE_SHIFT)
175
176 /* Construct the minor number from the device (d), mode (m), and non-rewind (n) data */
177 #define TAPE_MINOR(d, m, n) (((d & ~(255 >> (ST_NBR_MODE_BITS + 1))) << (ST_NBR_MODE_BITS + 1)) | \
178 (d & (255 >> (ST_NBR_MODE_BITS + 1))) | (m << ST_MODE_SHIFT) | ((n != 0) << 7) )
179
180 /* Internal ioctl to set both density (uppermost 8 bits) and blocksize (lower
181 24 bits) */
182 #define SET_DENS_AND_BLK 0x10001
183
184 static int st_fixed_buffer_size = ST_FIXED_BUFFER_SIZE;
185 static int st_max_sg_segs = ST_MAX_SG;
186
187 static int modes_defined;
188
189 static int enlarge_buffer(struct st_buffer *, int, int);
190 static void clear_buffer(struct st_buffer *);
191 static void normalize_buffer(struct st_buffer *);
192 static int append_to_buffer(const char __user *, struct st_buffer *, int);
193 static int from_buffer(struct st_buffer *, char __user *, int);
194 static void move_buffer_data(struct st_buffer *, int);
195
196 static int sgl_map_user_pages(struct st_buffer *, const unsigned int,
197 unsigned long, size_t, int);
198 static int sgl_unmap_user_pages(struct st_buffer *, const unsigned int, int);
199
200 static int st_probe(struct device *);
201 static int st_remove(struct device *);
202
203 static struct scsi_driver st_template = {
204 .gendrv = {
205 .name = "st",
206 .owner = THIS_MODULE,
207 .probe = st_probe,
208 .remove = st_remove,
209 .groups = st_drv_groups,
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 static DEFINE_SPINLOCK(st_index_lock);
226 static DEFINE_SPINLOCK(st_use_lock);
227 static DEFINE_IDR(st_index_idr);
228
229
230
231 #ifndef SIGS_FROM_OSST
232 #define SIGS_FROM_OSST \
233 {"OnStream", "SC-", "", "osst"}, \
234 {"OnStream", "DI-", "", "osst"}, \
235 {"OnStream", "DP-", "", "osst"}, \
236 {"OnStream", "USB", "", "osst"}, \
237 {"OnStream", "FW-", "", "osst"}
238 #endif
239
scsi_tape_get(int dev)240 static struct scsi_tape *scsi_tape_get(int dev)
241 {
242 struct scsi_tape *STp = NULL;
243
244 mutex_lock(&st_ref_mutex);
245 spin_lock(&st_index_lock);
246
247 STp = idr_find(&st_index_idr, dev);
248 if (!STp) goto out;
249
250 kref_get(&STp->kref);
251
252 if (!STp->device)
253 goto out_put;
254
255 if (scsi_device_get(STp->device))
256 goto out_put;
257
258 goto out;
259
260 out_put:
261 kref_put(&STp->kref, scsi_tape_release);
262 STp = NULL;
263 out:
264 spin_unlock(&st_index_lock);
265 mutex_unlock(&st_ref_mutex);
266 return STp;
267 }
268
scsi_tape_put(struct scsi_tape * STp)269 static void scsi_tape_put(struct scsi_tape *STp)
270 {
271 struct scsi_device *sdev = STp->device;
272
273 mutex_lock(&st_ref_mutex);
274 kref_put(&STp->kref, scsi_tape_release);
275 scsi_device_put(sdev);
276 mutex_unlock(&st_ref_mutex);
277 }
278
279 struct st_reject_data {
280 char *vendor;
281 char *model;
282 char *rev;
283 char *driver_hint; /* Name of the correct driver, NULL if unknown */
284 };
285
286 static struct st_reject_data reject_list[] = {
287 /* {"XXX", "Yy-", "", NULL}, example */
288 SIGS_FROM_OSST,
289 {NULL, }};
290
291 /* If the device signature is on the list of incompatible drives, the
292 function returns a pointer to the name of the correct driver (if known) */
st_incompatible(struct scsi_device * SDp)293 static char * st_incompatible(struct scsi_device* SDp)
294 {
295 struct st_reject_data *rp;
296
297 for (rp=&(reject_list[0]); rp->vendor != NULL; rp++)
298 if (!strncmp(rp->vendor, SDp->vendor, strlen(rp->vendor)) &&
299 !strncmp(rp->model, SDp->model, strlen(rp->model)) &&
300 !strncmp(rp->rev, SDp->rev, strlen(rp->rev))) {
301 if (rp->driver_hint)
302 return rp->driver_hint;
303 else
304 return "unknown";
305 }
306 return NULL;
307 }
308
309
tape_name(struct scsi_tape * tape)310 static inline char *tape_name(struct scsi_tape *tape)
311 {
312 return tape->disk->disk_name;
313 }
314
315 #define st_printk(prefix, t, fmt, a...) \
316 sdev_prefix_printk(prefix, (t)->device, tape_name(t), fmt, ##a)
317 #ifdef DEBUG
318 #define DEBC_printk(t, fmt, a...) \
319 if (debugging) { st_printk(ST_DEB_MSG, t, fmt, ##a ); }
320 #else
321 #define DEBC_printk(t, fmt, a...)
322 #endif
323
st_analyze_sense(struct st_request * SRpnt,struct st_cmdstatus * s)324 static void st_analyze_sense(struct st_request *SRpnt, struct st_cmdstatus *s)
325 {
326 const u8 *ucp;
327 const u8 *sense = SRpnt->sense;
328
329 s->have_sense = scsi_normalize_sense(SRpnt->sense,
330 SCSI_SENSE_BUFFERSIZE, &s->sense_hdr);
331 s->flags = 0;
332
333 if (s->have_sense) {
334 s->deferred = 0;
335 s->remainder_valid =
336 scsi_get_sense_info_fld(sense, SCSI_SENSE_BUFFERSIZE, &s->uremainder64);
337 switch (sense[0] & 0x7f) {
338 case 0x71:
339 s->deferred = 1;
340 /* fall through */
341 case 0x70:
342 s->fixed_format = 1;
343 s->flags = sense[2] & 0xe0;
344 break;
345 case 0x73:
346 s->deferred = 1;
347 /* fall through */
348 case 0x72:
349 s->fixed_format = 0;
350 ucp = scsi_sense_desc_find(sense, SCSI_SENSE_BUFFERSIZE, 4);
351 s->flags = ucp ? (ucp[3] & 0xe0) : 0;
352 break;
353 }
354 }
355 }
356
357
358 /* Convert the result to success code */
st_chk_result(struct scsi_tape * STp,struct st_request * SRpnt)359 static int st_chk_result(struct scsi_tape *STp, struct st_request * SRpnt)
360 {
361 int result = SRpnt->result;
362 u8 scode;
363 DEB(const char *stp;)
364 char *name = tape_name(STp);
365 struct st_cmdstatus *cmdstatp;
366
367 if (!result)
368 return 0;
369
370 cmdstatp = &STp->buffer->cmdstat;
371 st_analyze_sense(SRpnt, cmdstatp);
372
373 if (cmdstatp->have_sense)
374 scode = STp->buffer->cmdstat.sense_hdr.sense_key;
375 else
376 scode = 0;
377
378 DEB(
379 if (debugging) {
380 st_printk(ST_DEB_MSG, STp,
381 "Error: %x, cmd: %x %x %x %x %x %x\n", result,
382 SRpnt->cmd[0], SRpnt->cmd[1], SRpnt->cmd[2],
383 SRpnt->cmd[3], SRpnt->cmd[4], SRpnt->cmd[5]);
384 if (cmdstatp->have_sense)
385 __scsi_print_sense(STp->device, name,
386 SRpnt->sense, SCSI_SENSE_BUFFERSIZE);
387 } ) /* end DEB */
388 if (!debugging) { /* Abnormal conditions for tape */
389 if (!cmdstatp->have_sense)
390 st_printk(KERN_WARNING, STp,
391 "Error %x (driver bt 0x%x, host bt 0x%x).\n",
392 result, driver_byte(result), host_byte(result));
393 else if (cmdstatp->have_sense &&
394 scode != NO_SENSE &&
395 scode != RECOVERED_ERROR &&
396 /* scode != UNIT_ATTENTION && */
397 scode != BLANK_CHECK &&
398 scode != VOLUME_OVERFLOW &&
399 SRpnt->cmd[0] != MODE_SENSE &&
400 SRpnt->cmd[0] != TEST_UNIT_READY) {
401
402 __scsi_print_sense(STp->device, name,
403 SRpnt->sense, SCSI_SENSE_BUFFERSIZE);
404 }
405 }
406
407 if (cmdstatp->fixed_format &&
408 STp->cln_mode >= EXTENDED_SENSE_START) { /* Only fixed format sense */
409 if (STp->cln_sense_value)
410 STp->cleaning_req |= ((SRpnt->sense[STp->cln_mode] &
411 STp->cln_sense_mask) == STp->cln_sense_value);
412 else
413 STp->cleaning_req |= ((SRpnt->sense[STp->cln_mode] &
414 STp->cln_sense_mask) != 0);
415 }
416 if (cmdstatp->have_sense &&
417 cmdstatp->sense_hdr.asc == 0 && cmdstatp->sense_hdr.ascq == 0x17)
418 STp->cleaning_req = 1; /* ASC and ASCQ => cleaning requested */
419
420 STp->pos_unknown |= STp->device->was_reset;
421
422 if (cmdstatp->have_sense &&
423 scode == RECOVERED_ERROR
424 #if ST_RECOVERED_WRITE_FATAL
425 && SRpnt->cmd[0] != WRITE_6
426 && SRpnt->cmd[0] != WRITE_FILEMARKS
427 #endif
428 ) {
429 STp->recover_count++;
430 STp->recover_reg++;
431
432 DEB(
433 if (debugging) {
434 if (SRpnt->cmd[0] == READ_6)
435 stp = "read";
436 else if (SRpnt->cmd[0] == WRITE_6)
437 stp = "write";
438 else
439 stp = "ioctl";
440 st_printk(ST_DEB_MSG, STp,
441 "Recovered %s error (%d).\n",
442 stp, STp->recover_count);
443 } ) /* end DEB */
444
445 if (cmdstatp->flags == 0)
446 return 0;
447 }
448 return (-EIO);
449 }
450
st_allocate_request(struct scsi_tape * stp)451 static struct st_request *st_allocate_request(struct scsi_tape *stp)
452 {
453 struct st_request *streq;
454
455 streq = kzalloc(sizeof(*streq), GFP_KERNEL);
456 if (streq)
457 streq->stp = stp;
458 else {
459 st_printk(KERN_ERR, stp,
460 "Can't get SCSI request.\n");
461 if (signal_pending(current))
462 stp->buffer->syscall_result = -EINTR;
463 else
464 stp->buffer->syscall_result = -EBUSY;
465 }
466
467 return streq;
468 }
469
st_release_request(struct st_request * streq)470 static void st_release_request(struct st_request *streq)
471 {
472 kfree(streq);
473 }
474
st_do_stats(struct scsi_tape * STp,struct request * req)475 static void st_do_stats(struct scsi_tape *STp, struct request *req)
476 {
477 ktime_t now;
478
479 now = ktime_get();
480 if (scsi_req(req)->cmd[0] == WRITE_6) {
481 now = ktime_sub(now, STp->stats->write_time);
482 atomic64_add(ktime_to_ns(now), &STp->stats->tot_write_time);
483 atomic64_add(ktime_to_ns(now), &STp->stats->tot_io_time);
484 atomic64_inc(&STp->stats->write_cnt);
485 if (scsi_req(req)->result) {
486 atomic64_add(atomic_read(&STp->stats->last_write_size)
487 - STp->buffer->cmdstat.residual,
488 &STp->stats->write_byte_cnt);
489 if (STp->buffer->cmdstat.residual > 0)
490 atomic64_inc(&STp->stats->resid_cnt);
491 } else
492 atomic64_add(atomic_read(&STp->stats->last_write_size),
493 &STp->stats->write_byte_cnt);
494 } else if (scsi_req(req)->cmd[0] == READ_6) {
495 now = ktime_sub(now, STp->stats->read_time);
496 atomic64_add(ktime_to_ns(now), &STp->stats->tot_read_time);
497 atomic64_add(ktime_to_ns(now), &STp->stats->tot_io_time);
498 atomic64_inc(&STp->stats->read_cnt);
499 if (scsi_req(req)->result) {
500 atomic64_add(atomic_read(&STp->stats->last_read_size)
501 - STp->buffer->cmdstat.residual,
502 &STp->stats->read_byte_cnt);
503 if (STp->buffer->cmdstat.residual > 0)
504 atomic64_inc(&STp->stats->resid_cnt);
505 } else
506 atomic64_add(atomic_read(&STp->stats->last_read_size),
507 &STp->stats->read_byte_cnt);
508 } else {
509 now = ktime_sub(now, STp->stats->other_time);
510 atomic64_add(ktime_to_ns(now), &STp->stats->tot_io_time);
511 atomic64_inc(&STp->stats->other_cnt);
512 }
513 atomic64_dec(&STp->stats->in_flight);
514 }
515
st_scsi_execute_end(struct request * req,blk_status_t status)516 static void st_scsi_execute_end(struct request *req, blk_status_t status)
517 {
518 struct st_request *SRpnt = req->end_io_data;
519 struct scsi_request *rq = scsi_req(req);
520 struct scsi_tape *STp = SRpnt->stp;
521 struct bio *tmp;
522
523 STp->buffer->cmdstat.midlevel_result = SRpnt->result = rq->result;
524 STp->buffer->cmdstat.residual = rq->resid_len;
525
526 st_do_stats(STp, req);
527
528 tmp = SRpnt->bio;
529 if (rq->sense_len)
530 memcpy(SRpnt->sense, rq->sense, SCSI_SENSE_BUFFERSIZE);
531 if (SRpnt->waiting)
532 complete(SRpnt->waiting);
533
534 blk_rq_unmap_user(tmp);
535 blk_put_request(req);
536 }
537
st_scsi_execute(struct st_request * SRpnt,const unsigned char * cmd,int data_direction,void * buffer,unsigned bufflen,int timeout,int retries)538 static int st_scsi_execute(struct st_request *SRpnt, const unsigned char *cmd,
539 int data_direction, void *buffer, unsigned bufflen,
540 int timeout, int retries)
541 {
542 struct request *req;
543 struct scsi_request *rq;
544 struct rq_map_data *mdata = &SRpnt->stp->buffer->map_data;
545 int err = 0;
546 struct scsi_tape *STp = SRpnt->stp;
547
548 req = blk_get_request(SRpnt->stp->device->request_queue,
549 data_direction == DMA_TO_DEVICE ?
550 REQ_OP_SCSI_OUT : REQ_OP_SCSI_IN, 0);
551 if (IS_ERR(req))
552 return DRIVER_ERROR << 24;
553 rq = scsi_req(req);
554 req->rq_flags |= RQF_QUIET;
555
556 mdata->null_mapped = 1;
557
558 if (bufflen) {
559 err = blk_rq_map_user(req->q, req, mdata, NULL, bufflen,
560 GFP_KERNEL);
561 if (err) {
562 blk_put_request(req);
563 return DRIVER_ERROR << 24;
564 }
565 }
566
567 atomic64_inc(&STp->stats->in_flight);
568 if (cmd[0] == WRITE_6) {
569 atomic_set(&STp->stats->last_write_size, bufflen);
570 STp->stats->write_time = ktime_get();
571 } else if (cmd[0] == READ_6) {
572 atomic_set(&STp->stats->last_read_size, bufflen);
573 STp->stats->read_time = ktime_get();
574 } else {
575 STp->stats->other_time = ktime_get();
576 }
577
578 SRpnt->bio = req->bio;
579 rq->cmd_len = COMMAND_SIZE(cmd[0]);
580 memset(rq->cmd, 0, BLK_MAX_CDB);
581 memcpy(rq->cmd, cmd, rq->cmd_len);
582 req->timeout = timeout;
583 rq->retries = retries;
584 req->end_io_data = SRpnt;
585
586 blk_execute_rq_nowait(req->q, NULL, req, 1, st_scsi_execute_end);
587 return 0;
588 }
589
590 /* Do the scsi command. Waits until command performed if do_wait is true.
591 Otherwise write_behind_check() is used to check that the command
592 has finished. */
593 static struct st_request *
st_do_scsi(struct st_request * SRpnt,struct scsi_tape * STp,unsigned char * cmd,int bytes,int direction,int timeout,int retries,int do_wait)594 st_do_scsi(struct st_request * SRpnt, struct scsi_tape * STp, unsigned char *cmd,
595 int bytes, int direction, int timeout, int retries, int do_wait)
596 {
597 struct completion *waiting;
598 struct rq_map_data *mdata = &STp->buffer->map_data;
599 int ret;
600
601 /* if async, make sure there's no command outstanding */
602 if (!do_wait && ((STp->buffer)->last_SRpnt)) {
603 st_printk(KERN_ERR, STp,
604 "Async command already active.\n");
605 if (signal_pending(current))
606 (STp->buffer)->syscall_result = (-EINTR);
607 else
608 (STp->buffer)->syscall_result = (-EBUSY);
609 return NULL;
610 }
611
612 if (!SRpnt) {
613 SRpnt = st_allocate_request(STp);
614 if (!SRpnt)
615 return NULL;
616 }
617
618 /* If async IO, set last_SRpnt. This ptr tells write_behind_check
619 which IO is outstanding. It's nulled out when the IO completes. */
620 if (!do_wait)
621 (STp->buffer)->last_SRpnt = SRpnt;
622
623 waiting = &STp->wait;
624 init_completion(waiting);
625 SRpnt->waiting = waiting;
626
627 if (STp->buffer->do_dio) {
628 mdata->page_order = 0;
629 mdata->nr_entries = STp->buffer->sg_segs;
630 mdata->pages = STp->buffer->mapped_pages;
631 } else {
632 mdata->page_order = STp->buffer->reserved_page_order;
633 mdata->nr_entries =
634 DIV_ROUND_UP(bytes, PAGE_SIZE << mdata->page_order);
635 mdata->pages = STp->buffer->reserved_pages;
636 mdata->offset = 0;
637 }
638
639 memcpy(SRpnt->cmd, cmd, sizeof(SRpnt->cmd));
640 STp->buffer->cmdstat.have_sense = 0;
641 STp->buffer->syscall_result = 0;
642
643 ret = st_scsi_execute(SRpnt, cmd, direction, NULL, bytes, timeout,
644 retries);
645 if (ret) {
646 /* could not allocate the buffer or request was too large */
647 (STp->buffer)->syscall_result = (-EBUSY);
648 (STp->buffer)->last_SRpnt = NULL;
649 } else if (do_wait) {
650 wait_for_completion(waiting);
651 SRpnt->waiting = NULL;
652 (STp->buffer)->syscall_result = st_chk_result(STp, SRpnt);
653 }
654
655 return SRpnt;
656 }
657
658
659 /* Handle the write-behind checking (waits for completion). Returns -ENOSPC if
660 write has been correct but EOM early warning reached, -EIO if write ended in
661 error or zero if write successful. Asynchronous writes are used only in
662 variable block mode. */
write_behind_check(struct scsi_tape * STp)663 static int write_behind_check(struct scsi_tape * STp)
664 {
665 int retval = 0;
666 struct st_buffer *STbuffer;
667 struct st_partstat *STps;
668 struct st_cmdstatus *cmdstatp;
669 struct st_request *SRpnt;
670
671 STbuffer = STp->buffer;
672 if (!STbuffer->writing)
673 return 0;
674
675 DEB(
676 if (STp->write_pending)
677 STp->nbr_waits++;
678 else
679 STp->nbr_finished++;
680 ) /* end DEB */
681
682 wait_for_completion(&(STp->wait));
683 SRpnt = STbuffer->last_SRpnt;
684 STbuffer->last_SRpnt = NULL;
685 SRpnt->waiting = NULL;
686
687 (STp->buffer)->syscall_result = st_chk_result(STp, SRpnt);
688 st_release_request(SRpnt);
689
690 STbuffer->buffer_bytes -= STbuffer->writing;
691 STps = &(STp->ps[STp->partition]);
692 if (STps->drv_block >= 0) {
693 if (STp->block_size == 0)
694 STps->drv_block++;
695 else
696 STps->drv_block += STbuffer->writing / STp->block_size;
697 }
698
699 cmdstatp = &STbuffer->cmdstat;
700 if (STbuffer->syscall_result) {
701 retval = -EIO;
702 if (cmdstatp->have_sense && !cmdstatp->deferred &&
703 (cmdstatp->flags & SENSE_EOM) &&
704 (cmdstatp->sense_hdr.sense_key == NO_SENSE ||
705 cmdstatp->sense_hdr.sense_key == RECOVERED_ERROR)) {
706 /* EOM at write-behind, has all data been written? */
707 if (!cmdstatp->remainder_valid ||
708 cmdstatp->uremainder64 == 0)
709 retval = -ENOSPC;
710 }
711 if (retval == -EIO)
712 STps->drv_block = -1;
713 }
714 STbuffer->writing = 0;
715
716 DEB(if (debugging && retval)
717 st_printk(ST_DEB_MSG, STp,
718 "Async write error %x, return value %d.\n",
719 STbuffer->cmdstat.midlevel_result, retval);) /* end DEB */
720
721 return retval;
722 }
723
724
725 /* Step over EOF if it has been inadvertently crossed (ioctl not used because
726 it messes up the block number). */
cross_eof(struct scsi_tape * STp,int forward)727 static int cross_eof(struct scsi_tape * STp, int forward)
728 {
729 struct st_request *SRpnt;
730 unsigned char cmd[MAX_COMMAND_SIZE];
731
732 cmd[0] = SPACE;
733 cmd[1] = 0x01; /* Space FileMarks */
734 if (forward) {
735 cmd[2] = cmd[3] = 0;
736 cmd[4] = 1;
737 } else
738 cmd[2] = cmd[3] = cmd[4] = 0xff; /* -1 filemarks */
739 cmd[5] = 0;
740
741 DEBC_printk(STp, "Stepping over filemark %s.\n",
742 forward ? "forward" : "backward");
743
744 SRpnt = st_do_scsi(NULL, STp, cmd, 0, DMA_NONE,
745 STp->device->request_queue->rq_timeout,
746 MAX_RETRIES, 1);
747 if (!SRpnt)
748 return (STp->buffer)->syscall_result;
749
750 st_release_request(SRpnt);
751 SRpnt = NULL;
752
753 if ((STp->buffer)->cmdstat.midlevel_result != 0)
754 st_printk(KERN_ERR, STp,
755 "Stepping over filemark %s failed.\n",
756 forward ? "forward" : "backward");
757
758 return (STp->buffer)->syscall_result;
759 }
760
761
762 /* Flush the write buffer (never need to write if variable blocksize). */
st_flush_write_buffer(struct scsi_tape * STp)763 static int st_flush_write_buffer(struct scsi_tape * STp)
764 {
765 int transfer, blks;
766 int result;
767 unsigned char cmd[MAX_COMMAND_SIZE];
768 struct st_request *SRpnt;
769 struct st_partstat *STps;
770
771 result = write_behind_check(STp);
772 if (result)
773 return result;
774
775 result = 0;
776 if (STp->dirty == 1) {
777
778 transfer = STp->buffer->buffer_bytes;
779 DEBC_printk(STp, "Flushing %d bytes.\n", transfer);
780
781 memset(cmd, 0, MAX_COMMAND_SIZE);
782 cmd[0] = WRITE_6;
783 cmd[1] = 1;
784 blks = transfer / STp->block_size;
785 cmd[2] = blks >> 16;
786 cmd[3] = blks >> 8;
787 cmd[4] = blks;
788
789 SRpnt = st_do_scsi(NULL, STp, cmd, transfer, DMA_TO_DEVICE,
790 STp->device->request_queue->rq_timeout,
791 MAX_WRITE_RETRIES, 1);
792 if (!SRpnt)
793 return (STp->buffer)->syscall_result;
794
795 STps = &(STp->ps[STp->partition]);
796 if ((STp->buffer)->syscall_result != 0) {
797 struct st_cmdstatus *cmdstatp = &STp->buffer->cmdstat;
798
799 if (cmdstatp->have_sense && !cmdstatp->deferred &&
800 (cmdstatp->flags & SENSE_EOM) &&
801 (cmdstatp->sense_hdr.sense_key == NO_SENSE ||
802 cmdstatp->sense_hdr.sense_key == RECOVERED_ERROR) &&
803 (!cmdstatp->remainder_valid ||
804 cmdstatp->uremainder64 == 0)) { /* All written at EOM early warning */
805 STp->dirty = 0;
806 (STp->buffer)->buffer_bytes = 0;
807 if (STps->drv_block >= 0)
808 STps->drv_block += blks;
809 result = (-ENOSPC);
810 } else {
811 st_printk(KERN_ERR, STp, "Error on flush.\n");
812 STps->drv_block = (-1);
813 result = (-EIO);
814 }
815 } else {
816 if (STps->drv_block >= 0)
817 STps->drv_block += blks;
818 STp->dirty = 0;
819 (STp->buffer)->buffer_bytes = 0;
820 }
821 st_release_request(SRpnt);
822 SRpnt = NULL;
823 }
824 return result;
825 }
826
827
828 /* Flush the tape buffer. The tape will be positioned correctly unless
829 seek_next is true. */
flush_buffer(struct scsi_tape * STp,int seek_next)830 static int flush_buffer(struct scsi_tape *STp, int seek_next)
831 {
832 int backspace, result;
833 struct st_partstat *STps;
834
835 /*
836 * If there was a bus reset, block further access
837 * to this device.
838 */
839 if (STp->pos_unknown)
840 return (-EIO);
841
842 if (STp->ready != ST_READY)
843 return 0;
844 STps = &(STp->ps[STp->partition]);
845 if (STps->rw == ST_WRITING) /* Writing */
846 return st_flush_write_buffer(STp);
847
848 if (STp->block_size == 0)
849 return 0;
850
851 backspace = ((STp->buffer)->buffer_bytes +
852 (STp->buffer)->read_pointer) / STp->block_size -
853 ((STp->buffer)->read_pointer + STp->block_size - 1) /
854 STp->block_size;
855 (STp->buffer)->buffer_bytes = 0;
856 (STp->buffer)->read_pointer = 0;
857 result = 0;
858 if (!seek_next) {
859 if (STps->eof == ST_FM_HIT) {
860 result = cross_eof(STp, 0); /* Back over the EOF hit */
861 if (!result)
862 STps->eof = ST_NOEOF;
863 else {
864 if (STps->drv_file >= 0)
865 STps->drv_file++;
866 STps->drv_block = 0;
867 }
868 }
869 if (!result && backspace > 0)
870 result = st_int_ioctl(STp, MTBSR, backspace);
871 } else if (STps->eof == ST_FM_HIT) {
872 if (STps->drv_file >= 0)
873 STps->drv_file++;
874 STps->drv_block = 0;
875 STps->eof = ST_NOEOF;
876 }
877 return result;
878
879 }
880
881 /* Set the mode parameters */
set_mode_densblk(struct scsi_tape * STp,struct st_modedef * STm)882 static int set_mode_densblk(struct scsi_tape * STp, struct st_modedef * STm)
883 {
884 int set_it = 0;
885 unsigned long arg;
886
887 if (!STp->density_changed &&
888 STm->default_density >= 0 &&
889 STm->default_density != STp->density) {
890 arg = STm->default_density;
891 set_it = 1;
892 } else
893 arg = STp->density;
894 arg <<= MT_ST_DENSITY_SHIFT;
895 if (!STp->blksize_changed &&
896 STm->default_blksize >= 0 &&
897 STm->default_blksize != STp->block_size) {
898 arg |= STm->default_blksize;
899 set_it = 1;
900 } else
901 arg |= STp->block_size;
902 if (set_it &&
903 st_int_ioctl(STp, SET_DENS_AND_BLK, arg)) {
904 st_printk(KERN_WARNING, STp,
905 "Can't set default block size to %d bytes "
906 "and density %x.\n",
907 STm->default_blksize, STm->default_density);
908 if (modes_defined)
909 return (-EINVAL);
910 }
911 return 0;
912 }
913
914
915 /* Lock or unlock the drive door. Don't use when st_request allocated. */
do_door_lock(struct scsi_tape * STp,int do_lock)916 static int do_door_lock(struct scsi_tape * STp, int do_lock)
917 {
918 int retval;
919
920 DEBC_printk(STp, "%socking drive door.\n", do_lock ? "L" : "Unl");
921
922 retval = scsi_set_medium_removal(STp->device,
923 do_lock ? SCSI_REMOVAL_PREVENT : SCSI_REMOVAL_ALLOW);
924 if (!retval)
925 STp->door_locked = do_lock ? ST_LOCKED_EXPLICIT : ST_UNLOCKED;
926 else
927 STp->door_locked = ST_LOCK_FAILS;
928 return retval;
929 }
930
931
932 /* Set the internal state after reset */
reset_state(struct scsi_tape * STp)933 static void reset_state(struct scsi_tape *STp)
934 {
935 int i;
936 struct st_partstat *STps;
937
938 STp->pos_unknown = 0;
939 for (i = 0; i < ST_NBR_PARTITIONS; i++) {
940 STps = &(STp->ps[i]);
941 STps->rw = ST_IDLE;
942 STps->eof = ST_NOEOF;
943 STps->at_sm = 0;
944 STps->last_block_valid = 0;
945 STps->drv_block = -1;
946 STps->drv_file = -1;
947 }
948 if (STp->can_partitions) {
949 STp->partition = find_partition(STp);
950 if (STp->partition < 0)
951 STp->partition = 0;
952 STp->new_partition = STp->partition;
953 }
954 }
955
956 /* Test if the drive is ready. Returns either one of the codes below or a negative system
957 error code. */
958 #define CHKRES_READY 0
959 #define CHKRES_NEW_SESSION 1
960 #define CHKRES_NOT_READY 2
961 #define CHKRES_NO_TAPE 3
962
963 #define MAX_ATTENTIONS 10
964
test_ready(struct scsi_tape * STp,int do_wait)965 static int test_ready(struct scsi_tape *STp, int do_wait)
966 {
967 int attentions, waits, max_wait, scode;
968 int retval = CHKRES_READY, new_session = 0;
969 unsigned char cmd[MAX_COMMAND_SIZE];
970 struct st_request *SRpnt = NULL;
971 struct st_cmdstatus *cmdstatp = &STp->buffer->cmdstat;
972
973 max_wait = do_wait ? ST_BLOCK_SECONDS : 0;
974
975 for (attentions=waits=0; ; ) {
976 memset((void *) &cmd[0], 0, MAX_COMMAND_SIZE);
977 cmd[0] = TEST_UNIT_READY;
978 SRpnt = st_do_scsi(SRpnt, STp, cmd, 0, DMA_NONE,
979 STp->long_timeout, MAX_READY_RETRIES, 1);
980
981 if (!SRpnt) {
982 retval = (STp->buffer)->syscall_result;
983 break;
984 }
985
986 if (cmdstatp->have_sense) {
987
988 scode = cmdstatp->sense_hdr.sense_key;
989
990 if (scode == UNIT_ATTENTION) { /* New media? */
991 new_session = 1;
992 if (attentions < MAX_ATTENTIONS) {
993 attentions++;
994 continue;
995 }
996 else {
997 retval = (-EIO);
998 break;
999 }
1000 }
1001
1002 if (scode == NOT_READY) {
1003 if (waits < max_wait) {
1004 if (msleep_interruptible(1000)) {
1005 retval = (-EINTR);
1006 break;
1007 }
1008 waits++;
1009 continue;
1010 }
1011 else {
1012 if ((STp->device)->scsi_level >= SCSI_2 &&
1013 cmdstatp->sense_hdr.asc == 0x3a) /* Check ASC */
1014 retval = CHKRES_NO_TAPE;
1015 else
1016 retval = CHKRES_NOT_READY;
1017 break;
1018 }
1019 }
1020 }
1021
1022 retval = (STp->buffer)->syscall_result;
1023 if (!retval)
1024 retval = new_session ? CHKRES_NEW_SESSION : CHKRES_READY;
1025 break;
1026 }
1027
1028 if (SRpnt != NULL)
1029 st_release_request(SRpnt);
1030 return retval;
1031 }
1032
1033
1034 /* See if the drive is ready and gather information about the tape. Return values:
1035 < 0 negative error code from errno.h
1036 0 drive ready
1037 1 drive not ready (possibly no tape)
1038 */
check_tape(struct scsi_tape * STp,struct file * filp)1039 static int check_tape(struct scsi_tape *STp, struct file *filp)
1040 {
1041 int i, retval, new_session = 0, do_wait;
1042 unsigned char cmd[MAX_COMMAND_SIZE], saved_cleaning;
1043 unsigned short st_flags = filp->f_flags;
1044 struct st_request *SRpnt = NULL;
1045 struct st_modedef *STm;
1046 struct st_partstat *STps;
1047 struct inode *inode = file_inode(filp);
1048 int mode = TAPE_MODE(inode);
1049
1050 STp->ready = ST_READY;
1051
1052 if (mode != STp->current_mode) {
1053 DEBC_printk(STp, "Mode change from %d to %d.\n",
1054 STp->current_mode, mode);
1055 new_session = 1;
1056 STp->current_mode = mode;
1057 }
1058 STm = &(STp->modes[STp->current_mode]);
1059
1060 saved_cleaning = STp->cleaning_req;
1061 STp->cleaning_req = 0;
1062
1063 do_wait = ((filp->f_flags & O_NONBLOCK) == 0);
1064 retval = test_ready(STp, do_wait);
1065
1066 if (retval < 0)
1067 goto err_out;
1068
1069 if (retval == CHKRES_NEW_SESSION) {
1070 STp->pos_unknown = 0;
1071 STp->partition = STp->new_partition = 0;
1072 if (STp->can_partitions)
1073 STp->nbr_partitions = 1; /* This guess will be updated later
1074 if necessary */
1075 for (i = 0; i < ST_NBR_PARTITIONS; i++) {
1076 STps = &(STp->ps[i]);
1077 STps->rw = ST_IDLE;
1078 STps->eof = ST_NOEOF;
1079 STps->at_sm = 0;
1080 STps->last_block_valid = 0;
1081 STps->drv_block = 0;
1082 STps->drv_file = 0;
1083 }
1084 new_session = 1;
1085 }
1086 else {
1087 STp->cleaning_req |= saved_cleaning;
1088
1089 if (retval == CHKRES_NOT_READY || retval == CHKRES_NO_TAPE) {
1090 if (retval == CHKRES_NO_TAPE)
1091 STp->ready = ST_NO_TAPE;
1092 else
1093 STp->ready = ST_NOT_READY;
1094
1095 STp->density = 0; /* Clear the erroneous "residue" */
1096 STp->write_prot = 0;
1097 STp->block_size = 0;
1098 STp->ps[0].drv_file = STp->ps[0].drv_block = (-1);
1099 STp->partition = STp->new_partition = 0;
1100 STp->door_locked = ST_UNLOCKED;
1101 return CHKRES_NOT_READY;
1102 }
1103 }
1104
1105 if (STp->omit_blklims)
1106 STp->min_block = STp->max_block = (-1);
1107 else {
1108 memset((void *) &cmd[0], 0, MAX_COMMAND_SIZE);
1109 cmd[0] = READ_BLOCK_LIMITS;
1110
1111 SRpnt = st_do_scsi(SRpnt, STp, cmd, 6, DMA_FROM_DEVICE,
1112 STp->device->request_queue->rq_timeout,
1113 MAX_READY_RETRIES, 1);
1114 if (!SRpnt) {
1115 retval = (STp->buffer)->syscall_result;
1116 goto err_out;
1117 }
1118
1119 if (!SRpnt->result && !STp->buffer->cmdstat.have_sense) {
1120 STp->max_block = ((STp->buffer)->b_data[1] << 16) |
1121 ((STp->buffer)->b_data[2] << 8) | (STp->buffer)->b_data[3];
1122 STp->min_block = ((STp->buffer)->b_data[4] << 8) |
1123 (STp->buffer)->b_data[5];
1124 if ( DEB( debugging || ) !STp->inited)
1125 st_printk(KERN_INFO, STp,
1126 "Block limits %d - %d bytes.\n",
1127 STp->min_block, STp->max_block);
1128 } else {
1129 STp->min_block = STp->max_block = (-1);
1130 DEBC_printk(STp, "Can't read block limits.\n");
1131 }
1132 }
1133
1134 memset((void *) &cmd[0], 0, MAX_COMMAND_SIZE);
1135 cmd[0] = MODE_SENSE;
1136 cmd[4] = 12;
1137
1138 SRpnt = st_do_scsi(SRpnt, STp, cmd, 12, DMA_FROM_DEVICE,
1139 STp->device->request_queue->rq_timeout,
1140 MAX_READY_RETRIES, 1);
1141 if (!SRpnt) {
1142 retval = (STp->buffer)->syscall_result;
1143 goto err_out;
1144 }
1145
1146 if ((STp->buffer)->syscall_result != 0) {
1147 DEBC_printk(STp, "No Mode Sense.\n");
1148 STp->block_size = ST_DEFAULT_BLOCK; /* Educated guess (?) */
1149 (STp->buffer)->syscall_result = 0; /* Prevent error propagation */
1150 STp->drv_write_prot = 0;
1151 } else {
1152 DEBC_printk(STp,"Mode sense. Length %d, "
1153 "medium %x, WBS %x, BLL %d\n",
1154 (STp->buffer)->b_data[0],
1155 (STp->buffer)->b_data[1],
1156 (STp->buffer)->b_data[2],
1157 (STp->buffer)->b_data[3]);
1158
1159 if ((STp->buffer)->b_data[3] >= 8) {
1160 STp->drv_buffer = ((STp->buffer)->b_data[2] >> 4) & 7;
1161 STp->density = (STp->buffer)->b_data[4];
1162 STp->block_size = (STp->buffer)->b_data[9] * 65536 +
1163 (STp->buffer)->b_data[10] * 256 + (STp->buffer)->b_data[11];
1164 DEBC_printk(STp, "Density %x, tape length: %x, "
1165 "drv buffer: %d\n",
1166 STp->density,
1167 (STp->buffer)->b_data[5] * 65536 +
1168 (STp->buffer)->b_data[6] * 256 +
1169 (STp->buffer)->b_data[7],
1170 STp->drv_buffer);
1171 }
1172 STp->drv_write_prot = ((STp->buffer)->b_data[2] & 0x80) != 0;
1173 if (!STp->drv_buffer && STp->immediate_filemark) {
1174 st_printk(KERN_WARNING, STp,
1175 "non-buffered tape: disabling "
1176 "writing immediate filemarks\n");
1177 STp->immediate_filemark = 0;
1178 }
1179 }
1180 st_release_request(SRpnt);
1181 SRpnt = NULL;
1182 STp->inited = 1;
1183
1184 if (STp->block_size > 0)
1185 (STp->buffer)->buffer_blocks =
1186 (STp->buffer)->buffer_size / STp->block_size;
1187 else
1188 (STp->buffer)->buffer_blocks = 1;
1189 (STp->buffer)->buffer_bytes = (STp->buffer)->read_pointer = 0;
1190
1191 DEBC_printk(STp, "Block size: %d, buffer size: %d (%d blocks).\n",
1192 STp->block_size, (STp->buffer)->buffer_size,
1193 (STp->buffer)->buffer_blocks);
1194
1195 if (STp->drv_write_prot) {
1196 STp->write_prot = 1;
1197
1198 DEBC_printk(STp, "Write protected\n");
1199
1200 if (do_wait &&
1201 ((st_flags & O_ACCMODE) == O_WRONLY ||
1202 (st_flags & O_ACCMODE) == O_RDWR)) {
1203 retval = (-EROFS);
1204 goto err_out;
1205 }
1206 }
1207
1208 if (STp->can_partitions && STp->nbr_partitions < 1) {
1209 /* This code is reached when the device is opened for the first time
1210 after the driver has been initialized with tape in the drive and the
1211 partition support has been enabled. */
1212 DEBC_printk(STp, "Updating partition number in status.\n");
1213 if ((STp->partition = find_partition(STp)) < 0) {
1214 retval = STp->partition;
1215 goto err_out;
1216 }
1217 STp->new_partition = STp->partition;
1218 STp->nbr_partitions = 1; /* This guess will be updated when necessary */
1219 }
1220
1221 if (new_session) { /* Change the drive parameters for the new mode */
1222 STp->density_changed = STp->blksize_changed = 0;
1223 STp->compression_changed = 0;
1224 if (!(STm->defaults_for_writes) &&
1225 (retval = set_mode_densblk(STp, STm)) < 0)
1226 goto err_out;
1227
1228 if (STp->default_drvbuffer != 0xff) {
1229 if (st_int_ioctl(STp, MTSETDRVBUFFER, STp->default_drvbuffer))
1230 st_printk(KERN_WARNING, STp,
1231 "Can't set default drive "
1232 "buffering to %d.\n",
1233 STp->default_drvbuffer);
1234 }
1235 }
1236
1237 return CHKRES_READY;
1238
1239 err_out:
1240 return retval;
1241 }
1242
1243
1244 /* Open the device. Needs to take the BKL only because of incrementing the SCSI host
1245 module count. */
st_open(struct inode * inode,struct file * filp)1246 static int st_open(struct inode *inode, struct file *filp)
1247 {
1248 int i, retval = (-EIO);
1249 int resumed = 0;
1250 struct scsi_tape *STp;
1251 struct st_partstat *STps;
1252 int dev = TAPE_NR(inode);
1253
1254 /*
1255 * We really want to do nonseekable_open(inode, filp); here, but some
1256 * versions of tar incorrectly call lseek on tapes and bail out if that
1257 * fails. So we disallow pread() and pwrite(), but permit lseeks.
1258 */
1259 filp->f_mode &= ~(FMODE_PREAD | FMODE_PWRITE);
1260
1261 if (!(STp = scsi_tape_get(dev))) {
1262 return -ENXIO;
1263 }
1264
1265 filp->private_data = STp;
1266
1267 spin_lock(&st_use_lock);
1268 if (STp->in_use) {
1269 spin_unlock(&st_use_lock);
1270 scsi_tape_put(STp);
1271 DEBC_printk(STp, "Device already in use.\n");
1272 return (-EBUSY);
1273 }
1274
1275 STp->in_use = 1;
1276 spin_unlock(&st_use_lock);
1277 STp->rew_at_close = STp->autorew_dev = (iminor(inode) & 0x80) == 0;
1278
1279 if (scsi_autopm_get_device(STp->device) < 0) {
1280 retval = -EIO;
1281 goto err_out;
1282 }
1283 resumed = 1;
1284 if (!scsi_block_when_processing_errors(STp->device)) {
1285 retval = (-ENXIO);
1286 goto err_out;
1287 }
1288
1289 /* See that we have at least a one page buffer available */
1290 if (!enlarge_buffer(STp->buffer, PAGE_SIZE, STp->restr_dma)) {
1291 st_printk(KERN_WARNING, STp,
1292 "Can't allocate one page tape buffer.\n");
1293 retval = (-EOVERFLOW);
1294 goto err_out;
1295 }
1296
1297 (STp->buffer)->cleared = 0;
1298 (STp->buffer)->writing = 0;
1299 (STp->buffer)->syscall_result = 0;
1300
1301 STp->write_prot = ((filp->f_flags & O_ACCMODE) == O_RDONLY);
1302
1303 STp->dirty = 0;
1304 for (i = 0; i < ST_NBR_PARTITIONS; i++) {
1305 STps = &(STp->ps[i]);
1306 STps->rw = ST_IDLE;
1307 }
1308 STp->try_dio_now = STp->try_dio;
1309 STp->recover_count = 0;
1310 DEB( STp->nbr_waits = STp->nbr_finished = 0;
1311 STp->nbr_requests = STp->nbr_dio = STp->nbr_pages = 0; )
1312
1313 retval = check_tape(STp, filp);
1314 if (retval < 0)
1315 goto err_out;
1316 if ((filp->f_flags & O_NONBLOCK) == 0 &&
1317 retval != CHKRES_READY) {
1318 if (STp->ready == NO_TAPE)
1319 retval = (-ENOMEDIUM);
1320 else
1321 retval = (-EIO);
1322 goto err_out;
1323 }
1324 return 0;
1325
1326 err_out:
1327 normalize_buffer(STp->buffer);
1328 spin_lock(&st_use_lock);
1329 STp->in_use = 0;
1330 spin_unlock(&st_use_lock);
1331 if (resumed)
1332 scsi_autopm_put_device(STp->device);
1333 scsi_tape_put(STp);
1334 return retval;
1335
1336 }
1337
1338
1339 /* Flush the tape buffer before close */
st_flush(struct file * filp,fl_owner_t id)1340 static int st_flush(struct file *filp, fl_owner_t id)
1341 {
1342 int result = 0, result2;
1343 unsigned char cmd[MAX_COMMAND_SIZE];
1344 struct st_request *SRpnt;
1345 struct scsi_tape *STp = filp->private_data;
1346 struct st_modedef *STm = &(STp->modes[STp->current_mode]);
1347 struct st_partstat *STps = &(STp->ps[STp->partition]);
1348
1349 if (file_count(filp) > 1)
1350 return 0;
1351
1352 if (STps->rw == ST_WRITING && !STp->pos_unknown) {
1353 result = st_flush_write_buffer(STp);
1354 if (result != 0 && result != (-ENOSPC))
1355 goto out;
1356 }
1357
1358 if (STp->can_partitions &&
1359 (result2 = switch_partition(STp)) < 0) {
1360 DEBC_printk(STp, "switch_partition at close failed.\n");
1361 if (result == 0)
1362 result = result2;
1363 goto out;
1364 }
1365
1366 DEBC( if (STp->nbr_requests)
1367 st_printk(KERN_DEBUG, STp,
1368 "Number of r/w requests %d, dio used in %d, "
1369 "pages %d.\n", STp->nbr_requests, STp->nbr_dio,
1370 STp->nbr_pages));
1371
1372 if (STps->rw == ST_WRITING && !STp->pos_unknown) {
1373 struct st_cmdstatus *cmdstatp = &STp->buffer->cmdstat;
1374
1375 #if DEBUG
1376 DEBC_printk(STp, "Async write waits %d, finished %d.\n",
1377 STp->nbr_waits, STp->nbr_finished);
1378 #endif
1379 memset(cmd, 0, MAX_COMMAND_SIZE);
1380 cmd[0] = WRITE_FILEMARKS;
1381 if (STp->immediate_filemark)
1382 cmd[1] = 1;
1383 cmd[4] = 1 + STp->two_fm;
1384
1385 SRpnt = st_do_scsi(NULL, STp, cmd, 0, DMA_NONE,
1386 STp->device->request_queue->rq_timeout,
1387 MAX_WRITE_RETRIES, 1);
1388 if (!SRpnt) {
1389 result = (STp->buffer)->syscall_result;
1390 goto out;
1391 }
1392
1393 if (STp->buffer->syscall_result == 0 ||
1394 (cmdstatp->have_sense && !cmdstatp->deferred &&
1395 (cmdstatp->flags & SENSE_EOM) &&
1396 (cmdstatp->sense_hdr.sense_key == NO_SENSE ||
1397 cmdstatp->sense_hdr.sense_key == RECOVERED_ERROR) &&
1398 (!cmdstatp->remainder_valid || cmdstatp->uremainder64 == 0))) {
1399 /* Write successful at EOM */
1400 st_release_request(SRpnt);
1401 SRpnt = NULL;
1402 if (STps->drv_file >= 0)
1403 STps->drv_file++;
1404 STps->drv_block = 0;
1405 if (STp->two_fm)
1406 cross_eof(STp, 0);
1407 STps->eof = ST_FM;
1408 }
1409 else { /* Write error */
1410 st_release_request(SRpnt);
1411 SRpnt = NULL;
1412 st_printk(KERN_ERR, STp,
1413 "Error on write filemark.\n");
1414 if (result == 0)
1415 result = (-EIO);
1416 }
1417
1418 DEBC_printk(STp, "Buffer flushed, %d EOF(s) written\n", cmd[4]);
1419 } else if (!STp->rew_at_close) {
1420 STps = &(STp->ps[STp->partition]);
1421 if (!STm->sysv || STps->rw != ST_READING) {
1422 if (STp->can_bsr)
1423 result = flush_buffer(STp, 0);
1424 else if (STps->eof == ST_FM_HIT) {
1425 result = cross_eof(STp, 0);
1426 if (result) {
1427 if (STps->drv_file >= 0)
1428 STps->drv_file++;
1429 STps->drv_block = 0;
1430 STps->eof = ST_FM;
1431 } else
1432 STps->eof = ST_NOEOF;
1433 }
1434 } else if ((STps->eof == ST_NOEOF &&
1435 !(result = cross_eof(STp, 1))) ||
1436 STps->eof == ST_FM_HIT) {
1437 if (STps->drv_file >= 0)
1438 STps->drv_file++;
1439 STps->drv_block = 0;
1440 STps->eof = ST_FM;
1441 }
1442 }
1443
1444 out:
1445 if (STp->rew_at_close) {
1446 result2 = st_int_ioctl(STp, MTREW, 1);
1447 if (result == 0)
1448 result = result2;
1449 }
1450 return result;
1451 }
1452
1453
1454 /* Close the device and release it. BKL is not needed: this is the only thread
1455 accessing this tape. */
st_release(struct inode * inode,struct file * filp)1456 static int st_release(struct inode *inode, struct file *filp)
1457 {
1458 int result = 0;
1459 struct scsi_tape *STp = filp->private_data;
1460
1461 if (STp->door_locked == ST_LOCKED_AUTO)
1462 do_door_lock(STp, 0);
1463
1464 normalize_buffer(STp->buffer);
1465 spin_lock(&st_use_lock);
1466 STp->in_use = 0;
1467 spin_unlock(&st_use_lock);
1468 scsi_autopm_put_device(STp->device);
1469 scsi_tape_put(STp);
1470
1471 return result;
1472 }
1473
1474 /* The checks common to both reading and writing */
rw_checks(struct scsi_tape * STp,struct file * filp,size_t count)1475 static ssize_t rw_checks(struct scsi_tape *STp, struct file *filp, size_t count)
1476 {
1477 ssize_t retval = 0;
1478
1479 /*
1480 * If we are in the middle of error recovery, don't let anyone
1481 * else try and use this device. Also, if error recovery fails, it
1482 * may try and take the device offline, in which case all further
1483 * access to the device is prohibited.
1484 */
1485 if (!scsi_block_when_processing_errors(STp->device)) {
1486 retval = (-ENXIO);
1487 goto out;
1488 }
1489
1490 if (STp->ready != ST_READY) {
1491 if (STp->ready == ST_NO_TAPE)
1492 retval = (-ENOMEDIUM);
1493 else
1494 retval = (-EIO);
1495 goto out;
1496 }
1497
1498 if (! STp->modes[STp->current_mode].defined) {
1499 retval = (-ENXIO);
1500 goto out;
1501 }
1502
1503
1504 /*
1505 * If there was a bus reset, block further access
1506 * to this device.
1507 */
1508 if (STp->pos_unknown) {
1509 retval = (-EIO);
1510 goto out;
1511 }
1512
1513 if (count == 0)
1514 goto out;
1515
1516 DEB(
1517 if (!STp->in_use) {
1518 st_printk(ST_DEB_MSG, STp,
1519 "Incorrect device.\n");
1520 retval = (-EIO);
1521 goto out;
1522 } ) /* end DEB */
1523
1524 if (STp->can_partitions &&
1525 (retval = switch_partition(STp)) < 0)
1526 goto out;
1527
1528 if (STp->block_size == 0 && STp->max_block > 0 &&
1529 (count < STp->min_block || count > STp->max_block)) {
1530 retval = (-EINVAL);
1531 goto out;
1532 }
1533
1534 if (STp->do_auto_lock && STp->door_locked == ST_UNLOCKED &&
1535 !do_door_lock(STp, 1))
1536 STp->door_locked = ST_LOCKED_AUTO;
1537
1538 out:
1539 return retval;
1540 }
1541
1542
setup_buffering(struct scsi_tape * STp,const char __user * buf,size_t count,int is_read)1543 static int setup_buffering(struct scsi_tape *STp, const char __user *buf,
1544 size_t count, int is_read)
1545 {
1546 int i, bufsize, retval = 0;
1547 struct st_buffer *STbp = STp->buffer;
1548
1549 if (is_read)
1550 i = STp->try_dio_now && try_rdio;
1551 else
1552 i = STp->try_dio_now && try_wdio;
1553
1554 if (i && ((unsigned long)buf & queue_dma_alignment(
1555 STp->device->request_queue)) == 0) {
1556 i = sgl_map_user_pages(STbp, STbp->use_sg, (unsigned long)buf,
1557 count, (is_read ? READ : WRITE));
1558 if (i > 0) {
1559 STbp->do_dio = i;
1560 STbp->buffer_bytes = 0; /* can be used as transfer counter */
1561 }
1562 else
1563 STbp->do_dio = 0; /* fall back to buffering with any error */
1564 STbp->sg_segs = STbp->do_dio;
1565 DEB(
1566 if (STbp->do_dio) {
1567 STp->nbr_dio++;
1568 STp->nbr_pages += STbp->do_dio;
1569 }
1570 )
1571 } else
1572 STbp->do_dio = 0;
1573 DEB( STp->nbr_requests++; )
1574
1575 if (!STbp->do_dio) {
1576 if (STp->block_size)
1577 bufsize = STp->block_size > st_fixed_buffer_size ?
1578 STp->block_size : st_fixed_buffer_size;
1579 else {
1580 bufsize = count;
1581 /* Make sure that data from previous user is not leaked even if
1582 HBA does not return correct residual */
1583 if (is_read && STp->sili && !STbp->cleared)
1584 clear_buffer(STbp);
1585 }
1586
1587 if (bufsize > STbp->buffer_size &&
1588 !enlarge_buffer(STbp, bufsize, STp->restr_dma)) {
1589 st_printk(KERN_WARNING, STp,
1590 "Can't allocate %d byte tape buffer.\n",
1591 bufsize);
1592 retval = (-EOVERFLOW);
1593 goto out;
1594 }
1595 if (STp->block_size)
1596 STbp->buffer_blocks = bufsize / STp->block_size;
1597 }
1598
1599 out:
1600 return retval;
1601 }
1602
1603
1604 /* Can be called more than once after each setup_buffer() */
release_buffering(struct scsi_tape * STp,int is_read)1605 static void release_buffering(struct scsi_tape *STp, int is_read)
1606 {
1607 struct st_buffer *STbp;
1608
1609 STbp = STp->buffer;
1610 if (STbp->do_dio) {
1611 sgl_unmap_user_pages(STbp, STbp->do_dio, is_read);
1612 STbp->do_dio = 0;
1613 STbp->sg_segs = 0;
1614 }
1615 }
1616
1617
1618 /* Write command */
1619 static ssize_t
st_write(struct file * filp,const char __user * buf,size_t count,loff_t * ppos)1620 st_write(struct file *filp, const char __user *buf, size_t count, loff_t * ppos)
1621 {
1622 ssize_t total;
1623 ssize_t i, do_count, blks, transfer;
1624 ssize_t retval;
1625 int undone, retry_eot = 0, scode;
1626 int async_write;
1627 unsigned char cmd[MAX_COMMAND_SIZE];
1628 const char __user *b_point;
1629 struct st_request *SRpnt = NULL;
1630 struct scsi_tape *STp = filp->private_data;
1631 struct st_modedef *STm;
1632 struct st_partstat *STps;
1633 struct st_buffer *STbp;
1634
1635 if (mutex_lock_interruptible(&STp->lock))
1636 return -ERESTARTSYS;
1637
1638 retval = rw_checks(STp, filp, count);
1639 if (retval || count == 0)
1640 goto out;
1641
1642 /* Write must be integral number of blocks */
1643 if (STp->block_size != 0 && (count % STp->block_size) != 0) {
1644 st_printk(KERN_WARNING, STp,
1645 "Write not multiple of tape block size.\n");
1646 retval = (-EINVAL);
1647 goto out;
1648 }
1649
1650 STm = &(STp->modes[STp->current_mode]);
1651 STps = &(STp->ps[STp->partition]);
1652
1653 if (STp->write_prot) {
1654 retval = (-EACCES);
1655 goto out;
1656 }
1657
1658
1659 if (STps->rw == ST_READING) {
1660 retval = flush_buffer(STp, 0);
1661 if (retval)
1662 goto out;
1663 STps->rw = ST_WRITING;
1664 } else if (STps->rw != ST_WRITING &&
1665 STps->drv_file == 0 && STps->drv_block == 0) {
1666 if ((retval = set_mode_densblk(STp, STm)) < 0)
1667 goto out;
1668 if (STm->default_compression != ST_DONT_TOUCH &&
1669 !(STp->compression_changed)) {
1670 if (st_compression(STp, (STm->default_compression == ST_YES))) {
1671 st_printk(KERN_WARNING, STp,
1672 "Can't set default compression.\n");
1673 if (modes_defined) {
1674 retval = (-EINVAL);
1675 goto out;
1676 }
1677 }
1678 }
1679 }
1680
1681 STbp = STp->buffer;
1682 i = write_behind_check(STp);
1683 if (i) {
1684 if (i == -ENOSPC)
1685 STps->eof = ST_EOM_OK;
1686 else
1687 STps->eof = ST_EOM_ERROR;
1688 }
1689
1690 if (STps->eof == ST_EOM_OK) {
1691 STps->eof = ST_EOD_1; /* allow next write */
1692 retval = (-ENOSPC);
1693 goto out;
1694 }
1695 else if (STps->eof == ST_EOM_ERROR) {
1696 retval = (-EIO);
1697 goto out;
1698 }
1699
1700 /* Check the buffer readability in cases where copy_user might catch
1701 the problems after some tape movement. */
1702 if (STp->block_size != 0 &&
1703 !STbp->do_dio &&
1704 (copy_from_user(&i, buf, 1) != 0 ||
1705 copy_from_user(&i, buf + count - 1, 1) != 0)) {
1706 retval = (-EFAULT);
1707 goto out;
1708 }
1709
1710 retval = setup_buffering(STp, buf, count, 0);
1711 if (retval)
1712 goto out;
1713
1714 total = count;
1715
1716 memset(cmd, 0, MAX_COMMAND_SIZE);
1717 cmd[0] = WRITE_6;
1718 cmd[1] = (STp->block_size != 0);
1719
1720 STps->rw = ST_WRITING;
1721
1722 b_point = buf;
1723 while (count > 0 && !retry_eot) {
1724
1725 if (STbp->do_dio) {
1726 do_count = count;
1727 }
1728 else {
1729 if (STp->block_size == 0)
1730 do_count = count;
1731 else {
1732 do_count = STbp->buffer_blocks * STp->block_size -
1733 STbp->buffer_bytes;
1734 if (do_count > count)
1735 do_count = count;
1736 }
1737
1738 i = append_to_buffer(b_point, STbp, do_count);
1739 if (i) {
1740 retval = i;
1741 goto out;
1742 }
1743 }
1744 count -= do_count;
1745 b_point += do_count;
1746
1747 async_write = STp->block_size == 0 && !STbp->do_dio &&
1748 STm->do_async_writes && STps->eof < ST_EOM_OK;
1749
1750 if (STp->block_size != 0 && STm->do_buffer_writes &&
1751 !(STp->try_dio_now && try_wdio) && STps->eof < ST_EOM_OK &&
1752 STbp->buffer_bytes < STbp->buffer_size) {
1753 STp->dirty = 1;
1754 /* Don't write a buffer that is not full enough. */
1755 if (!async_write && count == 0)
1756 break;
1757 }
1758
1759 retry_write:
1760 if (STp->block_size == 0)
1761 blks = transfer = do_count;
1762 else {
1763 if (!STbp->do_dio)
1764 blks = STbp->buffer_bytes;
1765 else
1766 blks = do_count;
1767 blks /= STp->block_size;
1768 transfer = blks * STp->block_size;
1769 }
1770 cmd[2] = blks >> 16;
1771 cmd[3] = blks >> 8;
1772 cmd[4] = blks;
1773
1774 SRpnt = st_do_scsi(SRpnt, STp, cmd, transfer, DMA_TO_DEVICE,
1775 STp->device->request_queue->rq_timeout,
1776 MAX_WRITE_RETRIES, !async_write);
1777 if (!SRpnt) {
1778 retval = STbp->syscall_result;
1779 goto out;
1780 }
1781 if (async_write && !STbp->syscall_result) {
1782 STbp->writing = transfer;
1783 STp->dirty = !(STbp->writing ==
1784 STbp->buffer_bytes);
1785 SRpnt = NULL; /* Prevent releasing this request! */
1786 DEB( STp->write_pending = 1; )
1787 break;
1788 }
1789
1790 if (STbp->syscall_result != 0) {
1791 struct st_cmdstatus *cmdstatp = &STp->buffer->cmdstat;
1792
1793 DEBC_printk(STp, "Error on write:\n");
1794 if (cmdstatp->have_sense && (cmdstatp->flags & SENSE_EOM)) {
1795 scode = cmdstatp->sense_hdr.sense_key;
1796 if (cmdstatp->remainder_valid)
1797 undone = (int)cmdstatp->uremainder64;
1798 else if (STp->block_size == 0 &&
1799 scode == VOLUME_OVERFLOW)
1800 undone = transfer;
1801 else
1802 undone = 0;
1803 if (STp->block_size != 0)
1804 undone *= STp->block_size;
1805 if (undone <= do_count) {
1806 /* Only data from this write is not written */
1807 count += undone;
1808 b_point -= undone;
1809 do_count -= undone;
1810 if (STp->block_size)
1811 blks = (transfer - undone) / STp->block_size;
1812 STps->eof = ST_EOM_OK;
1813 /* Continue in fixed block mode if all written
1814 in this request but still something left to write
1815 (retval left to zero)
1816 */
1817 if (STp->block_size == 0 ||
1818 undone > 0 || count == 0)
1819 retval = (-ENOSPC); /* EOM within current request */
1820 DEBC_printk(STp, "EOM with %d "
1821 "bytes unwritten.\n",
1822 (int)count);
1823 } else {
1824 /* EOT within data buffered earlier (possible only
1825 in fixed block mode without direct i/o) */
1826 if (!retry_eot && !cmdstatp->deferred &&
1827 (scode == NO_SENSE || scode == RECOVERED_ERROR)) {
1828 move_buffer_data(STp->buffer, transfer - undone);
1829 retry_eot = 1;
1830 if (STps->drv_block >= 0) {
1831 STps->drv_block += (transfer - undone) /
1832 STp->block_size;
1833 }
1834 STps->eof = ST_EOM_OK;
1835 DEBC_printk(STp, "Retry "
1836 "write of %d "
1837 "bytes at EOM.\n",
1838 STp->buffer->buffer_bytes);
1839 goto retry_write;
1840 }
1841 else {
1842 /* Either error within data buffered by driver or
1843 failed retry */
1844 count -= do_count;
1845 blks = do_count = 0;
1846 STps->eof = ST_EOM_ERROR;
1847 STps->drv_block = (-1); /* Too cautious? */
1848 retval = (-EIO); /* EOM for old data */
1849 DEBC_printk(STp, "EOM with "
1850 "lost data.\n");
1851 }
1852 }
1853 } else {
1854 count += do_count;
1855 STps->drv_block = (-1); /* Too cautious? */
1856 retval = STbp->syscall_result;
1857 }
1858
1859 }
1860
1861 if (STps->drv_block >= 0) {
1862 if (STp->block_size == 0)
1863 STps->drv_block += (do_count > 0);
1864 else
1865 STps->drv_block += blks;
1866 }
1867
1868 STbp->buffer_bytes = 0;
1869 STp->dirty = 0;
1870
1871 if (retval || retry_eot) {
1872 if (count < total)
1873 retval = total - count;
1874 goto out;
1875 }
1876 }
1877
1878 if (STps->eof == ST_EOD_1)
1879 STps->eof = ST_EOM_OK;
1880 else if (STps->eof != ST_EOM_OK)
1881 STps->eof = ST_NOEOF;
1882 retval = total - count;
1883
1884 out:
1885 if (SRpnt != NULL)
1886 st_release_request(SRpnt);
1887 release_buffering(STp, 0);
1888 mutex_unlock(&STp->lock);
1889
1890 return retval;
1891 }
1892
1893 /* Read data from the tape. Returns zero in the normal case, one if the
1894 eof status has changed, and the negative error code in case of a
1895 fatal error. Otherwise updates the buffer and the eof state.
1896
1897 Does release user buffer mapping if it is set.
1898 */
read_tape(struct scsi_tape * STp,long count,struct st_request ** aSRpnt)1899 static long read_tape(struct scsi_tape *STp, long count,
1900 struct st_request ** aSRpnt)
1901 {
1902 int transfer, blks, bytes;
1903 unsigned char cmd[MAX_COMMAND_SIZE];
1904 struct st_request *SRpnt;
1905 struct st_modedef *STm;
1906 struct st_partstat *STps;
1907 struct st_buffer *STbp;
1908 int retval = 0;
1909
1910 if (count == 0)
1911 return 0;
1912
1913 STm = &(STp->modes[STp->current_mode]);
1914 STps = &(STp->ps[STp->partition]);
1915 if (STps->eof == ST_FM_HIT)
1916 return 1;
1917 STbp = STp->buffer;
1918
1919 if (STp->block_size == 0)
1920 blks = bytes = count;
1921 else {
1922 if (!(STp->try_dio_now && try_rdio) && STm->do_read_ahead) {
1923 blks = (STp->buffer)->buffer_blocks;
1924 bytes = blks * STp->block_size;
1925 } else {
1926 bytes = count;
1927 if (!STbp->do_dio && bytes > (STp->buffer)->buffer_size)
1928 bytes = (STp->buffer)->buffer_size;
1929 blks = bytes / STp->block_size;
1930 bytes = blks * STp->block_size;
1931 }
1932 }
1933
1934 memset(cmd, 0, MAX_COMMAND_SIZE);
1935 cmd[0] = READ_6;
1936 cmd[1] = (STp->block_size != 0);
1937 if (!cmd[1] && STp->sili)
1938 cmd[1] |= 2;
1939 cmd[2] = blks >> 16;
1940 cmd[3] = blks >> 8;
1941 cmd[4] = blks;
1942
1943 SRpnt = *aSRpnt;
1944 SRpnt = st_do_scsi(SRpnt, STp, cmd, bytes, DMA_FROM_DEVICE,
1945 STp->device->request_queue->rq_timeout,
1946 MAX_RETRIES, 1);
1947 release_buffering(STp, 1);
1948 *aSRpnt = SRpnt;
1949 if (!SRpnt)
1950 return STbp->syscall_result;
1951
1952 STbp->read_pointer = 0;
1953 STps->at_sm = 0;
1954
1955 /* Something to check */
1956 if (STbp->syscall_result) {
1957 struct st_cmdstatus *cmdstatp = &STp->buffer->cmdstat;
1958
1959 retval = 1;
1960 DEBC_printk(STp,
1961 "Sense: %2x %2x %2x %2x %2x %2x %2x %2x\n",
1962 SRpnt->sense[0], SRpnt->sense[1],
1963 SRpnt->sense[2], SRpnt->sense[3],
1964 SRpnt->sense[4], SRpnt->sense[5],
1965 SRpnt->sense[6], SRpnt->sense[7]);
1966 if (cmdstatp->have_sense) {
1967
1968 if (cmdstatp->sense_hdr.sense_key == BLANK_CHECK)
1969 cmdstatp->flags &= 0xcf; /* No need for EOM in this case */
1970
1971 if (cmdstatp->flags != 0) { /* EOF, EOM, or ILI */
1972 /* Compute the residual count */
1973 if (cmdstatp->remainder_valid)
1974 transfer = (int)cmdstatp->uremainder64;
1975 else
1976 transfer = 0;
1977 if (cmdstatp->sense_hdr.sense_key == MEDIUM_ERROR) {
1978 if (STp->block_size == 0)
1979 transfer = bytes;
1980 /* Some drives set ILI with MEDIUM ERROR */
1981 cmdstatp->flags &= ~SENSE_ILI;
1982 }
1983
1984 if (cmdstatp->flags & SENSE_ILI) { /* ILI */
1985 if (STp->block_size == 0 &&
1986 transfer < 0) {
1987 st_printk(KERN_NOTICE, STp,
1988 "Failed to read %d "
1989 "byte block with %d "
1990 "byte transfer.\n",
1991 bytes - transfer,
1992 bytes);
1993 if (STps->drv_block >= 0)
1994 STps->drv_block += 1;
1995 STbp->buffer_bytes = 0;
1996 return (-ENOMEM);
1997 } else if (STp->block_size == 0) {
1998 STbp->buffer_bytes = bytes - transfer;
1999 } else {
2000 st_release_request(SRpnt);
2001 SRpnt = *aSRpnt = NULL;
2002 if (transfer == blks) { /* We did not get anything, error */
2003 st_printk(KERN_NOTICE, STp,
2004 "Incorrect "
2005 "block size.\n");
2006 if (STps->drv_block >= 0)
2007 STps->drv_block += blks - transfer + 1;
2008 st_int_ioctl(STp, MTBSR, 1);
2009 return (-EIO);
2010 }
2011 /* We have some data, deliver it */
2012 STbp->buffer_bytes = (blks - transfer) *
2013 STp->block_size;
2014 DEBC_printk(STp, "ILI but "
2015 "enough data "
2016 "received %ld "
2017 "%d.\n", count,
2018 STbp->buffer_bytes);
2019 if (STps->drv_block >= 0)
2020 STps->drv_block += 1;
2021 if (st_int_ioctl(STp, MTBSR, 1))
2022 return (-EIO);
2023 }
2024 } else if (cmdstatp->flags & SENSE_FMK) { /* FM overrides EOM */
2025 if (STps->eof != ST_FM_HIT)
2026 STps->eof = ST_FM_HIT;
2027 else
2028 STps->eof = ST_EOD_2;
2029 if (STp->block_size == 0)
2030 STbp->buffer_bytes = 0;
2031 else
2032 STbp->buffer_bytes =
2033 bytes - transfer * STp->block_size;
2034 DEBC_printk(STp, "EOF detected (%d "
2035 "bytes read).\n",
2036 STbp->buffer_bytes);
2037 } else if (cmdstatp->flags & SENSE_EOM) {
2038 if (STps->eof == ST_FM)
2039 STps->eof = ST_EOD_1;
2040 else
2041 STps->eof = ST_EOM_OK;
2042 if (STp->block_size == 0)
2043 STbp->buffer_bytes = bytes - transfer;
2044 else
2045 STbp->buffer_bytes =
2046 bytes - transfer * STp->block_size;
2047
2048 DEBC_printk(STp, "EOM detected (%d "
2049 "bytes read).\n",
2050 STbp->buffer_bytes);
2051 }
2052 }
2053 /* end of EOF, EOM, ILI test */
2054 else { /* nonzero sense key */
2055 DEBC_printk(STp, "Tape error while reading.\n");
2056 STps->drv_block = (-1);
2057 if (STps->eof == ST_FM &&
2058 cmdstatp->sense_hdr.sense_key == BLANK_CHECK) {
2059 DEBC_printk(STp, "Zero returned for "
2060 "first BLANK CHECK "
2061 "after EOF.\n");
2062 STps->eof = ST_EOD_2; /* First BLANK_CHECK after FM */
2063 } else /* Some other extended sense code */
2064 retval = (-EIO);
2065 }
2066
2067 if (STbp->buffer_bytes < 0) /* Caused by bogus sense data */
2068 STbp->buffer_bytes = 0;
2069 }
2070 /* End of extended sense test */
2071 else { /* Non-extended sense */
2072 retval = STbp->syscall_result;
2073 }
2074
2075 }
2076 /* End of error handling */
2077 else { /* Read successful */
2078 STbp->buffer_bytes = bytes;
2079 if (STp->sili) /* In fixed block mode residual is always zero here */
2080 STbp->buffer_bytes -= STp->buffer->cmdstat.residual;
2081 }
2082
2083 if (STps->drv_block >= 0) {
2084 if (STp->block_size == 0)
2085 STps->drv_block++;
2086 else
2087 STps->drv_block += STbp->buffer_bytes / STp->block_size;
2088 }
2089 return retval;
2090 }
2091
2092
2093 /* Read command */
2094 static ssize_t
st_read(struct file * filp,char __user * buf,size_t count,loff_t * ppos)2095 st_read(struct file *filp, char __user *buf, size_t count, loff_t * ppos)
2096 {
2097 ssize_t total;
2098 ssize_t retval = 0;
2099 ssize_t i, transfer;
2100 int special, do_dio = 0;
2101 struct st_request *SRpnt = NULL;
2102 struct scsi_tape *STp = filp->private_data;
2103 struct st_modedef *STm;
2104 struct st_partstat *STps;
2105 struct st_buffer *STbp = STp->buffer;
2106
2107 if (mutex_lock_interruptible(&STp->lock))
2108 return -ERESTARTSYS;
2109
2110 retval = rw_checks(STp, filp, count);
2111 if (retval || count == 0)
2112 goto out;
2113
2114 STm = &(STp->modes[STp->current_mode]);
2115 if (STp->block_size != 0 && (count % STp->block_size) != 0) {
2116 if (!STm->do_read_ahead) {
2117 retval = (-EINVAL); /* Read must be integral number of blocks */
2118 goto out;
2119 }
2120 STp->try_dio_now = 0; /* Direct i/o can't handle split blocks */
2121 }
2122
2123 STps = &(STp->ps[STp->partition]);
2124 if (STps->rw == ST_WRITING) {
2125 retval = flush_buffer(STp, 0);
2126 if (retval)
2127 goto out;
2128 STps->rw = ST_READING;
2129 }
2130 DEB(
2131 if (debugging && STps->eof != ST_NOEOF)
2132 st_printk(ST_DEB_MSG, STp,
2133 "EOF/EOM flag up (%d). Bytes %d\n",
2134 STps->eof, STbp->buffer_bytes);
2135 ) /* end DEB */
2136
2137 retval = setup_buffering(STp, buf, count, 1);
2138 if (retval)
2139 goto out;
2140 do_dio = STbp->do_dio;
2141
2142 if (STbp->buffer_bytes == 0 &&
2143 STps->eof >= ST_EOD_1) {
2144 if (STps->eof < ST_EOD) {
2145 STps->eof += 1;
2146 retval = 0;
2147 goto out;
2148 }
2149 retval = (-EIO); /* EOM or Blank Check */
2150 goto out;
2151 }
2152
2153 if (do_dio) {
2154 /* Check the buffer writability before any tape movement. Don't alter
2155 buffer data. */
2156 if (copy_from_user(&i, buf, 1) != 0 ||
2157 copy_to_user(buf, &i, 1) != 0 ||
2158 copy_from_user(&i, buf + count - 1, 1) != 0 ||
2159 copy_to_user(buf + count - 1, &i, 1) != 0) {
2160 retval = (-EFAULT);
2161 goto out;
2162 }
2163 }
2164
2165 STps->rw = ST_READING;
2166
2167
2168 /* Loop until enough data in buffer or a special condition found */
2169 for (total = 0, special = 0; total < count && !special;) {
2170
2171 /* Get new data if the buffer is empty */
2172 if (STbp->buffer_bytes == 0) {
2173 special = read_tape(STp, count - total, &SRpnt);
2174 if (special < 0) { /* No need to continue read */
2175 retval = special;
2176 goto out;
2177 }
2178 }
2179
2180 /* Move the data from driver buffer to user buffer */
2181 if (STbp->buffer_bytes > 0) {
2182 DEB(
2183 if (debugging && STps->eof != ST_NOEOF)
2184 st_printk(ST_DEB_MSG, STp,
2185 "EOF up (%d). Left %d, needed %d.\n",
2186 STps->eof, STbp->buffer_bytes,
2187 (int)(count - total));
2188 ) /* end DEB */
2189 transfer = STbp->buffer_bytes < count - total ?
2190 STbp->buffer_bytes : count - total;
2191 if (!do_dio) {
2192 i = from_buffer(STbp, buf, transfer);
2193 if (i) {
2194 retval = i;
2195 goto out;
2196 }
2197 }
2198 buf += transfer;
2199 total += transfer;
2200 }
2201
2202 if (STp->block_size == 0)
2203 break; /* Read only one variable length block */
2204
2205 } /* for (total = 0, special = 0;
2206 total < count && !special; ) */
2207
2208 /* Change the eof state if no data from tape or buffer */
2209 if (total == 0) {
2210 if (STps->eof == ST_FM_HIT) {
2211 STps->eof = ST_FM;
2212 STps->drv_block = 0;
2213 if (STps->drv_file >= 0)
2214 STps->drv_file++;
2215 } else if (STps->eof == ST_EOD_1) {
2216 STps->eof = ST_EOD_2;
2217 STps->drv_block = 0;
2218 if (STps->drv_file >= 0)
2219 STps->drv_file++;
2220 } else if (STps->eof == ST_EOD_2)
2221 STps->eof = ST_EOD;
2222 } else if (STps->eof == ST_FM)
2223 STps->eof = ST_NOEOF;
2224 retval = total;
2225
2226 out:
2227 if (SRpnt != NULL) {
2228 st_release_request(SRpnt);
2229 SRpnt = NULL;
2230 }
2231 if (do_dio) {
2232 release_buffering(STp, 1);
2233 STbp->buffer_bytes = 0;
2234 }
2235 mutex_unlock(&STp->lock);
2236
2237 return retval;
2238 }
2239
2240
2241
DEB(static void st_log_options (struct scsi_tape * STp,struct st_modedef * STm){ if (debugging) { st_printk(KERN_INFO, STp, "Mode %d options: buffer writes: %d, " "async writes: %d, read ahead: %d\\n", STp->current_mode, STm->do_buffer_writes, STm->do_async_writes, STm->do_read_ahead); st_printk(KERN_INFO, STp, " can bsr: %d, two FMs: %d, " "fast mteom: %d, auto lock: %d,\\n", STp->can_bsr, STp->two_fm, STp->fast_mteom, STp->do_auto_lock); st_printk(KERN_INFO, STp, " defs for wr: %d, no block limits: %d, " "partitions: %d, s2 log: %d\\n", STm->defaults_for_writes, STp->omit_blklims, STp->can_partitions, STp->scsi2_logical); st_printk(KERN_INFO, STp, " sysv: %d nowait: %d sili: %d " "nowait_filemark: %d\\n", STm->sysv, STp->immediate, STp->sili, STp->immediate_filemark); st_printk(KERN_INFO, STp, " debugging: %d\\n", debugging); } } )2242 DEB(
2243 /* Set the driver options */
2244 static void st_log_options(struct scsi_tape * STp, struct st_modedef * STm)
2245 {
2246 if (debugging) {
2247 st_printk(KERN_INFO, STp,
2248 "Mode %d options: buffer writes: %d, "
2249 "async writes: %d, read ahead: %d\n",
2250 STp->current_mode, STm->do_buffer_writes,
2251 STm->do_async_writes, STm->do_read_ahead);
2252 st_printk(KERN_INFO, STp,
2253 " can bsr: %d, two FMs: %d, "
2254 "fast mteom: %d, auto lock: %d,\n",
2255 STp->can_bsr, STp->two_fm, STp->fast_mteom,
2256 STp->do_auto_lock);
2257 st_printk(KERN_INFO, STp,
2258 " defs for wr: %d, no block limits: %d, "
2259 "partitions: %d, s2 log: %d\n",
2260 STm->defaults_for_writes, STp->omit_blklims,
2261 STp->can_partitions, STp->scsi2_logical);
2262 st_printk(KERN_INFO, STp,
2263 " sysv: %d nowait: %d sili: %d "
2264 "nowait_filemark: %d\n",
2265 STm->sysv, STp->immediate, STp->sili,
2266 STp->immediate_filemark);
2267 st_printk(KERN_INFO, STp, " debugging: %d\n", debugging);
2268 }
2269 }
2270 )
2271
2272
2273 static int st_set_options(struct scsi_tape *STp, long options)
2274 {
2275 int value;
2276 long code;
2277 struct st_modedef *STm;
2278 struct cdev *cd0, *cd1;
2279 struct device *d0, *d1;
2280
2281 STm = &(STp->modes[STp->current_mode]);
2282 if (!STm->defined) {
2283 cd0 = STm->cdevs[0];
2284 cd1 = STm->cdevs[1];
2285 d0 = STm->devs[0];
2286 d1 = STm->devs[1];
2287 memcpy(STm, &(STp->modes[0]), sizeof(struct st_modedef));
2288 STm->cdevs[0] = cd0;
2289 STm->cdevs[1] = cd1;
2290 STm->devs[0] = d0;
2291 STm->devs[1] = d1;
2292 modes_defined = 1;
2293 DEBC_printk(STp, "Initialized mode %d definition from mode 0\n",
2294 STp->current_mode);
2295 }
2296
2297 code = options & MT_ST_OPTIONS;
2298 if (code == MT_ST_BOOLEANS) {
2299 STm->do_buffer_writes = (options & MT_ST_BUFFER_WRITES) != 0;
2300 STm->do_async_writes = (options & MT_ST_ASYNC_WRITES) != 0;
2301 STm->defaults_for_writes = (options & MT_ST_DEF_WRITES) != 0;
2302 STm->do_read_ahead = (options & MT_ST_READ_AHEAD) != 0;
2303 STp->two_fm = (options & MT_ST_TWO_FM) != 0;
2304 STp->fast_mteom = (options & MT_ST_FAST_MTEOM) != 0;
2305 STp->do_auto_lock = (options & MT_ST_AUTO_LOCK) != 0;
2306 STp->can_bsr = (options & MT_ST_CAN_BSR) != 0;
2307 STp->omit_blklims = (options & MT_ST_NO_BLKLIMS) != 0;
2308 if ((STp->device)->scsi_level >= SCSI_2)
2309 STp->can_partitions = (options & MT_ST_CAN_PARTITIONS) != 0;
2310 STp->scsi2_logical = (options & MT_ST_SCSI2LOGICAL) != 0;
2311 STp->immediate = (options & MT_ST_NOWAIT) != 0;
2312 STp->immediate_filemark = (options & MT_ST_NOWAIT_EOF) != 0;
2313 STm->sysv = (options & MT_ST_SYSV) != 0;
2314 STp->sili = (options & MT_ST_SILI) != 0;
2315 DEB( debugging = (options & MT_ST_DEBUGGING) != 0;
2316 st_log_options(STp, STm); )
2317 } else if (code == MT_ST_SETBOOLEANS || code == MT_ST_CLEARBOOLEANS) {
2318 value = (code == MT_ST_SETBOOLEANS);
2319 if ((options & MT_ST_BUFFER_WRITES) != 0)
2320 STm->do_buffer_writes = value;
2321 if ((options & MT_ST_ASYNC_WRITES) != 0)
2322 STm->do_async_writes = value;
2323 if ((options & MT_ST_DEF_WRITES) != 0)
2324 STm->defaults_for_writes = value;
2325 if ((options & MT_ST_READ_AHEAD) != 0)
2326 STm->do_read_ahead = value;
2327 if ((options & MT_ST_TWO_FM) != 0)
2328 STp->two_fm = value;
2329 if ((options & MT_ST_FAST_MTEOM) != 0)
2330 STp->fast_mteom = value;
2331 if ((options & MT_ST_AUTO_LOCK) != 0)
2332 STp->do_auto_lock = value;
2333 if ((options & MT_ST_CAN_BSR) != 0)
2334 STp->can_bsr = value;
2335 if ((options & MT_ST_NO_BLKLIMS) != 0)
2336 STp->omit_blklims = value;
2337 if ((STp->device)->scsi_level >= SCSI_2 &&
2338 (options & MT_ST_CAN_PARTITIONS) != 0)
2339 STp->can_partitions = value;
2340 if ((options & MT_ST_SCSI2LOGICAL) != 0)
2341 STp->scsi2_logical = value;
2342 if ((options & MT_ST_NOWAIT) != 0)
2343 STp->immediate = value;
2344 if ((options & MT_ST_NOWAIT_EOF) != 0)
2345 STp->immediate_filemark = value;
2346 if ((options & MT_ST_SYSV) != 0)
2347 STm->sysv = value;
2348 if ((options & MT_ST_SILI) != 0)
2349 STp->sili = value;
2350 DEB(
2351 if ((options & MT_ST_DEBUGGING) != 0)
2352 debugging = value;
2353 st_log_options(STp, STm); )
2354 } else if (code == MT_ST_WRITE_THRESHOLD) {
2355 /* Retained for compatibility */
2356 } else if (code == MT_ST_DEF_BLKSIZE) {
2357 value = (options & ~MT_ST_OPTIONS);
2358 if (value == ~MT_ST_OPTIONS) {
2359 STm->default_blksize = (-1);
2360 DEBC_printk(STp, "Default block size disabled.\n");
2361 } else {
2362 STm->default_blksize = value;
2363 DEBC_printk(STp,"Default block size set to "
2364 "%d bytes.\n", STm->default_blksize);
2365 if (STp->ready == ST_READY) {
2366 STp->blksize_changed = 0;
2367 set_mode_densblk(STp, STm);
2368 }
2369 }
2370 } else if (code == MT_ST_TIMEOUTS) {
2371 value = (options & ~MT_ST_OPTIONS);
2372 if ((value & MT_ST_SET_LONG_TIMEOUT) != 0) {
2373 STp->long_timeout = (value & ~MT_ST_SET_LONG_TIMEOUT) * HZ;
2374 DEBC_printk(STp, "Long timeout set to %d seconds.\n",
2375 (value & ~MT_ST_SET_LONG_TIMEOUT));
2376 } else {
2377 blk_queue_rq_timeout(STp->device->request_queue,
2378 value * HZ);
2379 DEBC_printk(STp, "Normal timeout set to %d seconds.\n",
2380 value);
2381 }
2382 } else if (code == MT_ST_SET_CLN) {
2383 value = (options & ~MT_ST_OPTIONS) & 0xff;
2384 if (value != 0 &&
2385 (value < EXTENDED_SENSE_START ||
2386 value >= SCSI_SENSE_BUFFERSIZE))
2387 return (-EINVAL);
2388 STp->cln_mode = value;
2389 STp->cln_sense_mask = (options >> 8) & 0xff;
2390 STp->cln_sense_value = (options >> 16) & 0xff;
2391 st_printk(KERN_INFO, STp,
2392 "Cleaning request mode %d, mask %02x, value %02x\n",
2393 value, STp->cln_sense_mask, STp->cln_sense_value);
2394 } else if (code == MT_ST_DEF_OPTIONS) {
2395 code = (options & ~MT_ST_CLEAR_DEFAULT);
2396 value = (options & MT_ST_CLEAR_DEFAULT);
2397 if (code == MT_ST_DEF_DENSITY) {
2398 if (value == MT_ST_CLEAR_DEFAULT) {
2399 STm->default_density = (-1);
2400 DEBC_printk(STp,
2401 "Density default disabled.\n");
2402 } else {
2403 STm->default_density = value & 0xff;
2404 DEBC_printk(STp, "Density default set to %x\n",
2405 STm->default_density);
2406 if (STp->ready == ST_READY) {
2407 STp->density_changed = 0;
2408 set_mode_densblk(STp, STm);
2409 }
2410 }
2411 } else if (code == MT_ST_DEF_DRVBUFFER) {
2412 if (value == MT_ST_CLEAR_DEFAULT) {
2413 STp->default_drvbuffer = 0xff;
2414 DEBC_printk(STp,
2415 "Drive buffer default disabled.\n");
2416 } else {
2417 STp->default_drvbuffer = value & 7;
2418 DEBC_printk(STp,
2419 "Drive buffer default set to %x\n",
2420 STp->default_drvbuffer);
2421 if (STp->ready == ST_READY)
2422 st_int_ioctl(STp, MTSETDRVBUFFER, STp->default_drvbuffer);
2423 }
2424 } else if (code == MT_ST_DEF_COMPRESSION) {
2425 if (value == MT_ST_CLEAR_DEFAULT) {
2426 STm->default_compression = ST_DONT_TOUCH;
2427 DEBC_printk(STp,
2428 "Compression default disabled.\n");
2429 } else {
2430 if ((value & 0xff00) != 0) {
2431 STp->c_algo = (value & 0xff00) >> 8;
2432 DEBC_printk(STp, "Compression "
2433 "algorithm set to 0x%x.\n",
2434 STp->c_algo);
2435 }
2436 if ((value & 0xff) != 0xff) {
2437 STm->default_compression = (value & 1 ? ST_YES : ST_NO);
2438 DEBC_printk(STp, "Compression default "
2439 "set to %x\n",
2440 (value & 1));
2441 if (STp->ready == ST_READY) {
2442 STp->compression_changed = 0;
2443 st_compression(STp, (STm->default_compression == ST_YES));
2444 }
2445 }
2446 }
2447 }
2448 } else
2449 return (-EIO);
2450
2451 return 0;
2452 }
2453
2454 #define MODE_HEADER_LENGTH 4
2455
2456 /* Mode header and page byte offsets */
2457 #define MH_OFF_DATA_LENGTH 0
2458 #define MH_OFF_MEDIUM_TYPE 1
2459 #define MH_OFF_DEV_SPECIFIC 2
2460 #define MH_OFF_BDESCS_LENGTH 3
2461 #define MP_OFF_PAGE_NBR 0
2462 #define MP_OFF_PAGE_LENGTH 1
2463
2464 /* Mode header and page bit masks */
2465 #define MH_BIT_WP 0x80
2466 #define MP_MSK_PAGE_NBR 0x3f
2467
2468 /* Don't return block descriptors */
2469 #define MODE_SENSE_OMIT_BDESCS 0x08
2470
2471 #define MODE_SELECT_PAGE_FORMAT 0x10
2472
2473 /* Read a mode page into the tape buffer. The block descriptors are included
2474 if incl_block_descs is true. The page control is ored to the page number
2475 parameter, if necessary. */
read_mode_page(struct scsi_tape * STp,int page,int omit_block_descs)2476 static int read_mode_page(struct scsi_tape *STp, int page, int omit_block_descs)
2477 {
2478 unsigned char cmd[MAX_COMMAND_SIZE];
2479 struct st_request *SRpnt;
2480
2481 memset(cmd, 0, MAX_COMMAND_SIZE);
2482 cmd[0] = MODE_SENSE;
2483 if (omit_block_descs)
2484 cmd[1] = MODE_SENSE_OMIT_BDESCS;
2485 cmd[2] = page;
2486 cmd[4] = 255;
2487
2488 SRpnt = st_do_scsi(NULL, STp, cmd, cmd[4], DMA_FROM_DEVICE,
2489 STp->device->request_queue->rq_timeout, 0, 1);
2490 if (SRpnt == NULL)
2491 return (STp->buffer)->syscall_result;
2492
2493 st_release_request(SRpnt);
2494
2495 return STp->buffer->syscall_result;
2496 }
2497
2498
2499 /* Send the mode page in the tape buffer to the drive. Assumes that the mode data
2500 in the buffer is correctly formatted. The long timeout is used if slow is non-zero. */
write_mode_page(struct scsi_tape * STp,int page,int slow)2501 static int write_mode_page(struct scsi_tape *STp, int page, int slow)
2502 {
2503 int pgo;
2504 unsigned char cmd[MAX_COMMAND_SIZE];
2505 struct st_request *SRpnt;
2506 int timeout;
2507
2508 memset(cmd, 0, MAX_COMMAND_SIZE);
2509 cmd[0] = MODE_SELECT;
2510 cmd[1] = MODE_SELECT_PAGE_FORMAT;
2511 pgo = MODE_HEADER_LENGTH + (STp->buffer)->b_data[MH_OFF_BDESCS_LENGTH];
2512 cmd[4] = pgo + (STp->buffer)->b_data[pgo + MP_OFF_PAGE_LENGTH] + 2;
2513
2514 /* Clear reserved fields */
2515 (STp->buffer)->b_data[MH_OFF_DATA_LENGTH] = 0;
2516 (STp->buffer)->b_data[MH_OFF_MEDIUM_TYPE] = 0;
2517 (STp->buffer)->b_data[MH_OFF_DEV_SPECIFIC] &= ~MH_BIT_WP;
2518 (STp->buffer)->b_data[pgo + MP_OFF_PAGE_NBR] &= MP_MSK_PAGE_NBR;
2519
2520 timeout = slow ?
2521 STp->long_timeout : STp->device->request_queue->rq_timeout;
2522 SRpnt = st_do_scsi(NULL, STp, cmd, cmd[4], DMA_TO_DEVICE,
2523 timeout, 0, 1);
2524 if (SRpnt == NULL)
2525 return (STp->buffer)->syscall_result;
2526
2527 st_release_request(SRpnt);
2528
2529 return STp->buffer->syscall_result;
2530 }
2531
2532
2533 #define COMPRESSION_PAGE 0x0f
2534 #define COMPRESSION_PAGE_LENGTH 16
2535
2536 #define CP_OFF_DCE_DCC 2
2537 #define CP_OFF_C_ALGO 7
2538
2539 #define DCE_MASK 0x80
2540 #define DCC_MASK 0x40
2541 #define RED_MASK 0x60
2542
2543
2544 /* Control the compression with mode page 15. Algorithm not changed if zero.
2545
2546 The block descriptors are read and written because Sony SDT-7000 does not
2547 work without this (suggestion from Michael Schaefer <Michael.Schaefer@dlr.de>).
2548 Including block descriptors should not cause any harm to other drives. */
2549
st_compression(struct scsi_tape * STp,int state)2550 static int st_compression(struct scsi_tape * STp, int state)
2551 {
2552 int retval;
2553 int mpoffs; /* Offset to mode page start */
2554 unsigned char *b_data = (STp->buffer)->b_data;
2555
2556 if (STp->ready != ST_READY)
2557 return (-EIO);
2558
2559 /* Read the current page contents */
2560 retval = read_mode_page(STp, COMPRESSION_PAGE, 0);
2561 if (retval) {
2562 DEBC_printk(STp, "Compression mode page not supported.\n");
2563 return (-EIO);
2564 }
2565
2566 mpoffs = MODE_HEADER_LENGTH + b_data[MH_OFF_BDESCS_LENGTH];
2567 DEBC_printk(STp, "Compression state is %d.\n",
2568 (b_data[mpoffs + CP_OFF_DCE_DCC] & DCE_MASK ? 1 : 0));
2569
2570 /* Check if compression can be changed */
2571 if ((b_data[mpoffs + CP_OFF_DCE_DCC] & DCC_MASK) == 0) {
2572 DEBC_printk(STp, "Compression not supported.\n");
2573 return (-EIO);
2574 }
2575
2576 /* Do the change */
2577 if (state) {
2578 b_data[mpoffs + CP_OFF_DCE_DCC] |= DCE_MASK;
2579 if (STp->c_algo != 0)
2580 b_data[mpoffs + CP_OFF_C_ALGO] = STp->c_algo;
2581 }
2582 else {
2583 b_data[mpoffs + CP_OFF_DCE_DCC] &= ~DCE_MASK;
2584 if (STp->c_algo != 0)
2585 b_data[mpoffs + CP_OFF_C_ALGO] = 0; /* no compression */
2586 }
2587
2588 retval = write_mode_page(STp, COMPRESSION_PAGE, 0);
2589 if (retval) {
2590 DEBC_printk(STp, "Compression change failed.\n");
2591 return (-EIO);
2592 }
2593 DEBC_printk(STp, "Compression state changed to %d.\n", state);
2594
2595 STp->compression_changed = 1;
2596 return 0;
2597 }
2598
2599
2600 /* Process the load and unload commands (does unload if the load code is zero) */
do_load_unload(struct scsi_tape * STp,struct file * filp,int load_code)2601 static int do_load_unload(struct scsi_tape *STp, struct file *filp, int load_code)
2602 {
2603 int retval = (-EIO), timeout;
2604 unsigned char cmd[MAX_COMMAND_SIZE];
2605 struct st_partstat *STps;
2606 struct st_request *SRpnt;
2607
2608 if (STp->ready != ST_READY && !load_code) {
2609 if (STp->ready == ST_NO_TAPE)
2610 return (-ENOMEDIUM);
2611 else
2612 return (-EIO);
2613 }
2614
2615 memset(cmd, 0, MAX_COMMAND_SIZE);
2616 cmd[0] = START_STOP;
2617 if (load_code)
2618 cmd[4] |= 1;
2619 /*
2620 * If arg >= 1 && arg <= 6 Enhanced load/unload in HP C1553A
2621 */
2622 if (load_code >= 1 + MT_ST_HPLOADER_OFFSET
2623 && load_code <= 6 + MT_ST_HPLOADER_OFFSET) {
2624 DEBC_printk(STp, " Enhanced %sload slot %2d.\n",
2625 (cmd[4]) ? "" : "un",
2626 load_code - MT_ST_HPLOADER_OFFSET);
2627 cmd[3] = load_code - MT_ST_HPLOADER_OFFSET; /* MediaID field of C1553A */
2628 }
2629 if (STp->immediate) {
2630 cmd[1] = 1; /* Don't wait for completion */
2631 timeout = STp->device->request_queue->rq_timeout;
2632 }
2633 else
2634 timeout = STp->long_timeout;
2635
2636 DEBC(
2637 if (!load_code)
2638 st_printk(ST_DEB_MSG, STp, "Unloading tape.\n");
2639 else
2640 st_printk(ST_DEB_MSG, STp, "Loading tape.\n");
2641 );
2642
2643 SRpnt = st_do_scsi(NULL, STp, cmd, 0, DMA_NONE,
2644 timeout, MAX_RETRIES, 1);
2645 if (!SRpnt)
2646 return (STp->buffer)->syscall_result;
2647
2648 retval = (STp->buffer)->syscall_result;
2649 st_release_request(SRpnt);
2650
2651 if (!retval) { /* SCSI command successful */
2652
2653 if (!load_code) {
2654 STp->rew_at_close = 0;
2655 STp->ready = ST_NO_TAPE;
2656 }
2657 else {
2658 STp->rew_at_close = STp->autorew_dev;
2659 retval = check_tape(STp, filp);
2660 if (retval > 0)
2661 retval = 0;
2662 }
2663 }
2664 else {
2665 STps = &(STp->ps[STp->partition]);
2666 STps->drv_file = STps->drv_block = (-1);
2667 }
2668
2669 return retval;
2670 }
2671
2672 #if DEBUG
2673 #define ST_DEB_FORWARD 0
2674 #define ST_DEB_BACKWARD 1
deb_space_print(struct scsi_tape * STp,int direction,char * units,unsigned char * cmd)2675 static void deb_space_print(struct scsi_tape *STp, int direction, char *units, unsigned char *cmd)
2676 {
2677 s32 sc;
2678
2679 if (!debugging)
2680 return;
2681
2682 sc = cmd[2] & 0x80 ? 0xff000000 : 0;
2683 sc |= (cmd[2] << 16) | (cmd[3] << 8) | cmd[4];
2684 if (direction)
2685 sc = -sc;
2686 st_printk(ST_DEB_MSG, STp, "Spacing tape %s over %d %s.\n",
2687 direction ? "backward" : "forward", sc, units);
2688 }
2689 #else
2690 #define ST_DEB_FORWARD 0
2691 #define ST_DEB_BACKWARD 1
deb_space_print(struct scsi_tape * STp,int direction,char * units,unsigned char * cmd)2692 static void deb_space_print(struct scsi_tape *STp, int direction, char *units, unsigned char *cmd) {}
2693 #endif
2694
2695
2696 /* Internal ioctl function */
st_int_ioctl(struct scsi_tape * STp,unsigned int cmd_in,unsigned long arg)2697 static int st_int_ioctl(struct scsi_tape *STp, unsigned int cmd_in, unsigned long arg)
2698 {
2699 int timeout;
2700 long ltmp;
2701 int ioctl_result;
2702 int chg_eof = 1;
2703 unsigned char cmd[MAX_COMMAND_SIZE];
2704 struct st_request *SRpnt;
2705 struct st_partstat *STps;
2706 int fileno, blkno, at_sm, undone;
2707 int datalen = 0, direction = DMA_NONE;
2708
2709 WARN_ON(STp->buffer->do_dio != 0);
2710 if (STp->ready != ST_READY) {
2711 if (STp->ready == ST_NO_TAPE)
2712 return (-ENOMEDIUM);
2713 else
2714 return (-EIO);
2715 }
2716 timeout = STp->long_timeout;
2717 STps = &(STp->ps[STp->partition]);
2718 fileno = STps->drv_file;
2719 blkno = STps->drv_block;
2720 at_sm = STps->at_sm;
2721
2722 memset(cmd, 0, MAX_COMMAND_SIZE);
2723 switch (cmd_in) {
2724 case MTFSFM:
2725 chg_eof = 0; /* Changed from the FSF after this */
2726 /* fall through */
2727 case MTFSF:
2728 cmd[0] = SPACE;
2729 cmd[1] = 0x01; /* Space FileMarks */
2730 cmd[2] = (arg >> 16);
2731 cmd[3] = (arg >> 8);
2732 cmd[4] = arg;
2733 deb_space_print(STp, ST_DEB_FORWARD, "filemarks", cmd);
2734 if (fileno >= 0)
2735 fileno += arg;
2736 blkno = 0;
2737 at_sm &= (arg == 0);
2738 break;
2739 case MTBSFM:
2740 chg_eof = 0; /* Changed from the FSF after this */
2741 /* fall through */
2742 case MTBSF:
2743 cmd[0] = SPACE;
2744 cmd[1] = 0x01; /* Space FileMarks */
2745 ltmp = (-arg);
2746 cmd[2] = (ltmp >> 16);
2747 cmd[3] = (ltmp >> 8);
2748 cmd[4] = ltmp;
2749 deb_space_print(STp, ST_DEB_BACKWARD, "filemarks", cmd);
2750 if (fileno >= 0)
2751 fileno -= arg;
2752 blkno = (-1); /* We can't know the block number */
2753 at_sm &= (arg == 0);
2754 break;
2755 case MTFSR:
2756 cmd[0] = SPACE;
2757 cmd[1] = 0x00; /* Space Blocks */
2758 cmd[2] = (arg >> 16);
2759 cmd[3] = (arg >> 8);
2760 cmd[4] = arg;
2761 deb_space_print(STp, ST_DEB_FORWARD, "blocks", cmd);
2762 if (blkno >= 0)
2763 blkno += arg;
2764 at_sm &= (arg == 0);
2765 break;
2766 case MTBSR:
2767 cmd[0] = SPACE;
2768 cmd[1] = 0x00; /* Space Blocks */
2769 ltmp = (-arg);
2770 cmd[2] = (ltmp >> 16);
2771 cmd[3] = (ltmp >> 8);
2772 cmd[4] = ltmp;
2773 deb_space_print(STp, ST_DEB_BACKWARD, "blocks", cmd);
2774 if (blkno >= 0)
2775 blkno -= arg;
2776 at_sm &= (arg == 0);
2777 break;
2778 case MTFSS:
2779 cmd[0] = SPACE;
2780 cmd[1] = 0x04; /* Space Setmarks */
2781 cmd[2] = (arg >> 16);
2782 cmd[3] = (arg >> 8);
2783 cmd[4] = arg;
2784 deb_space_print(STp, ST_DEB_FORWARD, "setmarks", cmd);
2785 if (arg != 0) {
2786 blkno = fileno = (-1);
2787 at_sm = 1;
2788 }
2789 break;
2790 case MTBSS:
2791 cmd[0] = SPACE;
2792 cmd[1] = 0x04; /* Space Setmarks */
2793 ltmp = (-arg);
2794 cmd[2] = (ltmp >> 16);
2795 cmd[3] = (ltmp >> 8);
2796 cmd[4] = ltmp;
2797 deb_space_print(STp, ST_DEB_BACKWARD, "setmarks", cmd);
2798 if (arg != 0) {
2799 blkno = fileno = (-1);
2800 at_sm = 1;
2801 }
2802 break;
2803 case MTWEOF:
2804 case MTWEOFI:
2805 case MTWSM:
2806 if (STp->write_prot)
2807 return (-EACCES);
2808 cmd[0] = WRITE_FILEMARKS;
2809 if (cmd_in == MTWSM)
2810 cmd[1] = 2;
2811 if (cmd_in == MTWEOFI ||
2812 (cmd_in == MTWEOF && STp->immediate_filemark))
2813 cmd[1] |= 1;
2814 cmd[2] = (arg >> 16);
2815 cmd[3] = (arg >> 8);
2816 cmd[4] = arg;
2817 timeout = STp->device->request_queue->rq_timeout;
2818 DEBC(
2819 if (cmd_in != MTWSM)
2820 st_printk(ST_DEB_MSG, STp,
2821 "Writing %d filemarks.\n",
2822 cmd[2] * 65536 +
2823 cmd[3] * 256 +
2824 cmd[4]);
2825 else
2826 st_printk(ST_DEB_MSG, STp,
2827 "Writing %d setmarks.\n",
2828 cmd[2] * 65536 +
2829 cmd[3] * 256 +
2830 cmd[4]);
2831 )
2832 if (fileno >= 0)
2833 fileno += arg;
2834 blkno = 0;
2835 at_sm = (cmd_in == MTWSM);
2836 break;
2837 case MTREW:
2838 cmd[0] = REZERO_UNIT;
2839 if (STp->immediate) {
2840 cmd[1] = 1; /* Don't wait for completion */
2841 timeout = STp->device->request_queue->rq_timeout;
2842 }
2843 DEBC_printk(STp, "Rewinding tape.\n");
2844 fileno = blkno = at_sm = 0;
2845 break;
2846 case MTNOP:
2847 DEBC_printk(STp, "No op on tape.\n");
2848 return 0; /* Should do something ? */
2849 break;
2850 case MTRETEN:
2851 cmd[0] = START_STOP;
2852 if (STp->immediate) {
2853 cmd[1] = 1; /* Don't wait for completion */
2854 timeout = STp->device->request_queue->rq_timeout;
2855 }
2856 cmd[4] = 3;
2857 DEBC_printk(STp, "Retensioning tape.\n");
2858 fileno = blkno = at_sm = 0;
2859 break;
2860 case MTEOM:
2861 if (!STp->fast_mteom) {
2862 /* space to the end of tape */
2863 ioctl_result = st_int_ioctl(STp, MTFSF, 0x7fffff);
2864 fileno = STps->drv_file;
2865 if (STps->eof >= ST_EOD_1)
2866 return 0;
2867 /* The next lines would hide the number of spaced FileMarks
2868 That's why I inserted the previous lines. I had no luck
2869 with detecting EOM with FSF, so we go now to EOM.
2870 Joerg Weule */
2871 } else
2872 fileno = (-1);
2873 cmd[0] = SPACE;
2874 cmd[1] = 3;
2875 DEBC_printk(STp, "Spacing to end of recorded medium.\n");
2876 blkno = -1;
2877 at_sm = 0;
2878 break;
2879 case MTERASE:
2880 if (STp->write_prot)
2881 return (-EACCES);
2882 cmd[0] = ERASE;
2883 cmd[1] = (arg ? 1 : 0); /* Long erase with non-zero argument */
2884 if (STp->immediate) {
2885 cmd[1] |= 2; /* Don't wait for completion */
2886 timeout = STp->device->request_queue->rq_timeout;
2887 }
2888 else
2889 timeout = STp->long_timeout * 8;
2890
2891 DEBC_printk(STp, "Erasing tape.\n");
2892 fileno = blkno = at_sm = 0;
2893 break;
2894 case MTSETBLK: /* Set block length */
2895 case MTSETDENSITY: /* Set tape density */
2896 case MTSETDRVBUFFER: /* Set drive buffering */
2897 case SET_DENS_AND_BLK: /* Set density and block size */
2898 chg_eof = 0;
2899 if (STp->dirty || (STp->buffer)->buffer_bytes != 0)
2900 return (-EIO); /* Not allowed if data in buffer */
2901 if ((cmd_in == MTSETBLK || cmd_in == SET_DENS_AND_BLK) &&
2902 (arg & MT_ST_BLKSIZE_MASK) != 0 &&
2903 STp->max_block > 0 &&
2904 ((arg & MT_ST_BLKSIZE_MASK) < STp->min_block ||
2905 (arg & MT_ST_BLKSIZE_MASK) > STp->max_block)) {
2906 st_printk(KERN_WARNING, STp, "Illegal block size.\n");
2907 return (-EINVAL);
2908 }
2909 cmd[0] = MODE_SELECT;
2910 if ((STp->use_pf & USE_PF))
2911 cmd[1] = MODE_SELECT_PAGE_FORMAT;
2912 cmd[4] = datalen = 12;
2913 direction = DMA_TO_DEVICE;
2914
2915 memset((STp->buffer)->b_data, 0, 12);
2916 if (cmd_in == MTSETDRVBUFFER)
2917 (STp->buffer)->b_data[2] = (arg & 7) << 4;
2918 else
2919 (STp->buffer)->b_data[2] =
2920 STp->drv_buffer << 4;
2921 (STp->buffer)->b_data[3] = 8; /* block descriptor length */
2922 if (cmd_in == MTSETDENSITY) {
2923 (STp->buffer)->b_data[4] = arg;
2924 STp->density_changed = 1; /* At least we tried ;-) */
2925 } else if (cmd_in == SET_DENS_AND_BLK)
2926 (STp->buffer)->b_data[4] = arg >> 24;
2927 else
2928 (STp->buffer)->b_data[4] = STp->density;
2929 if (cmd_in == MTSETBLK || cmd_in == SET_DENS_AND_BLK) {
2930 ltmp = arg & MT_ST_BLKSIZE_MASK;
2931 if (cmd_in == MTSETBLK)
2932 STp->blksize_changed = 1; /* At least we tried ;-) */
2933 } else
2934 ltmp = STp->block_size;
2935 (STp->buffer)->b_data[9] = (ltmp >> 16);
2936 (STp->buffer)->b_data[10] = (ltmp >> 8);
2937 (STp->buffer)->b_data[11] = ltmp;
2938 timeout = STp->device->request_queue->rq_timeout;
2939 DEBC(
2940 if (cmd_in == MTSETBLK || cmd_in == SET_DENS_AND_BLK)
2941 st_printk(ST_DEB_MSG, STp,
2942 "Setting block size to %d bytes.\n",
2943 (STp->buffer)->b_data[9] * 65536 +
2944 (STp->buffer)->b_data[10] * 256 +
2945 (STp->buffer)->b_data[11]);
2946 if (cmd_in == MTSETDENSITY || cmd_in == SET_DENS_AND_BLK)
2947 st_printk(ST_DEB_MSG, STp,
2948 "Setting density code to %x.\n",
2949 (STp->buffer)->b_data[4]);
2950 if (cmd_in == MTSETDRVBUFFER)
2951 st_printk(ST_DEB_MSG, STp,
2952 "Setting drive buffer code to %d.\n",
2953 ((STp->buffer)->b_data[2] >> 4) & 7);
2954 )
2955 break;
2956 default:
2957 return (-ENOSYS);
2958 }
2959
2960 SRpnt = st_do_scsi(NULL, STp, cmd, datalen, direction,
2961 timeout, MAX_RETRIES, 1);
2962 if (!SRpnt)
2963 return (STp->buffer)->syscall_result;
2964
2965 ioctl_result = (STp->buffer)->syscall_result;
2966
2967 if (!ioctl_result) { /* SCSI command successful */
2968 st_release_request(SRpnt);
2969 SRpnt = NULL;
2970 STps->drv_block = blkno;
2971 STps->drv_file = fileno;
2972 STps->at_sm = at_sm;
2973
2974 if (cmd_in == MTBSFM)
2975 ioctl_result = st_int_ioctl(STp, MTFSF, 1);
2976 else if (cmd_in == MTFSFM)
2977 ioctl_result = st_int_ioctl(STp, MTBSF, 1);
2978
2979 if (cmd_in == MTSETBLK || cmd_in == SET_DENS_AND_BLK) {
2980 STp->block_size = arg & MT_ST_BLKSIZE_MASK;
2981 if (STp->block_size != 0) {
2982 (STp->buffer)->buffer_blocks =
2983 (STp->buffer)->buffer_size / STp->block_size;
2984 }
2985 (STp->buffer)->buffer_bytes = (STp->buffer)->read_pointer = 0;
2986 if (cmd_in == SET_DENS_AND_BLK)
2987 STp->density = arg >> MT_ST_DENSITY_SHIFT;
2988 } else if (cmd_in == MTSETDRVBUFFER)
2989 STp->drv_buffer = (arg & 7);
2990 else if (cmd_in == MTSETDENSITY)
2991 STp->density = arg;
2992
2993 if (cmd_in == MTEOM)
2994 STps->eof = ST_EOD;
2995 else if (cmd_in == MTFSF)
2996 STps->eof = ST_FM;
2997 else if (chg_eof)
2998 STps->eof = ST_NOEOF;
2999
3000 if (cmd_in == MTWEOF || cmd_in == MTWEOFI)
3001 STps->rw = ST_IDLE; /* prevent automatic WEOF at close */
3002 } else { /* SCSI command was not completely successful. Don't return
3003 from this block without releasing the SCSI command block! */
3004 struct st_cmdstatus *cmdstatp = &STp->buffer->cmdstat;
3005
3006 if (cmdstatp->flags & SENSE_EOM) {
3007 if (cmd_in != MTBSF && cmd_in != MTBSFM &&
3008 cmd_in != MTBSR && cmd_in != MTBSS)
3009 STps->eof = ST_EOM_OK;
3010 STps->drv_block = 0;
3011 }
3012
3013 if (cmdstatp->remainder_valid)
3014 undone = (int)cmdstatp->uremainder64;
3015 else
3016 undone = 0;
3017
3018 if ((cmd_in == MTWEOF || cmd_in == MTWEOFI) &&
3019 cmdstatp->have_sense &&
3020 (cmdstatp->flags & SENSE_EOM)) {
3021 if (cmdstatp->sense_hdr.sense_key == NO_SENSE ||
3022 cmdstatp->sense_hdr.sense_key == RECOVERED_ERROR) {
3023 ioctl_result = 0; /* EOF(s) written successfully at EOM */
3024 STps->eof = ST_NOEOF;
3025 } else { /* Writing EOF(s) failed */
3026 if (fileno >= 0)
3027 fileno -= undone;
3028 if (undone < arg)
3029 STps->eof = ST_NOEOF;
3030 }
3031 STps->drv_file = fileno;
3032 } else if ((cmd_in == MTFSF) || (cmd_in == MTFSFM)) {
3033 if (fileno >= 0)
3034 STps->drv_file = fileno - undone;
3035 else
3036 STps->drv_file = fileno;
3037 STps->drv_block = -1;
3038 STps->eof = ST_NOEOF;
3039 } else if ((cmd_in == MTBSF) || (cmd_in == MTBSFM)) {
3040 if (arg > 0 && undone < 0) /* Some drives get this wrong */
3041 undone = (-undone);
3042 if (STps->drv_file >= 0)
3043 STps->drv_file = fileno + undone;
3044 STps->drv_block = 0;
3045 STps->eof = ST_NOEOF;
3046 } else if (cmd_in == MTFSR) {
3047 if (cmdstatp->flags & SENSE_FMK) { /* Hit filemark */
3048 if (STps->drv_file >= 0)
3049 STps->drv_file++;
3050 STps->drv_block = 0;
3051 STps->eof = ST_FM;
3052 } else {
3053 if (blkno >= undone)
3054 STps->drv_block = blkno - undone;
3055 else
3056 STps->drv_block = (-1);
3057 STps->eof = ST_NOEOF;
3058 }
3059 } else if (cmd_in == MTBSR) {
3060 if (cmdstatp->flags & SENSE_FMK) { /* Hit filemark */
3061 STps->drv_file--;
3062 STps->drv_block = (-1);
3063 } else {
3064 if (arg > 0 && undone < 0) /* Some drives get this wrong */
3065 undone = (-undone);
3066 if (STps->drv_block >= 0)
3067 STps->drv_block = blkno + undone;
3068 }
3069 STps->eof = ST_NOEOF;
3070 } else if (cmd_in == MTEOM) {
3071 STps->drv_file = (-1);
3072 STps->drv_block = (-1);
3073 STps->eof = ST_EOD;
3074 } else if (cmd_in == MTSETBLK ||
3075 cmd_in == MTSETDENSITY ||
3076 cmd_in == MTSETDRVBUFFER ||
3077 cmd_in == SET_DENS_AND_BLK) {
3078 if (cmdstatp->sense_hdr.sense_key == ILLEGAL_REQUEST &&
3079 !(STp->use_pf & PF_TESTED)) {
3080 /* Try the other possible state of Page Format if not
3081 already tried */
3082 STp->use_pf = (STp->use_pf ^ USE_PF) | PF_TESTED;
3083 st_release_request(SRpnt);
3084 SRpnt = NULL;
3085 return st_int_ioctl(STp, cmd_in, arg);
3086 }
3087 } else if (chg_eof)
3088 STps->eof = ST_NOEOF;
3089
3090 if (cmdstatp->sense_hdr.sense_key == BLANK_CHECK)
3091 STps->eof = ST_EOD;
3092
3093 st_release_request(SRpnt);
3094 SRpnt = NULL;
3095 }
3096
3097 return ioctl_result;
3098 }
3099
3100
3101 /* Get the tape position. If bt == 2, arg points into a kernel space mt_loc
3102 structure. */
3103
get_location(struct scsi_tape * STp,unsigned int * block,int * partition,int logical)3104 static int get_location(struct scsi_tape *STp, unsigned int *block, int *partition,
3105 int logical)
3106 {
3107 int result;
3108 unsigned char scmd[MAX_COMMAND_SIZE];
3109 struct st_request *SRpnt;
3110
3111 if (STp->ready != ST_READY)
3112 return (-EIO);
3113
3114 memset(scmd, 0, MAX_COMMAND_SIZE);
3115 if ((STp->device)->scsi_level < SCSI_2) {
3116 scmd[0] = QFA_REQUEST_BLOCK;
3117 scmd[4] = 3;
3118 } else {
3119 scmd[0] = READ_POSITION;
3120 if (!logical && !STp->scsi2_logical)
3121 scmd[1] = 1;
3122 }
3123 SRpnt = st_do_scsi(NULL, STp, scmd, 20, DMA_FROM_DEVICE,
3124 STp->device->request_queue->rq_timeout,
3125 MAX_READY_RETRIES, 1);
3126 if (!SRpnt)
3127 return (STp->buffer)->syscall_result;
3128
3129 if ((STp->buffer)->syscall_result != 0 ||
3130 (STp->device->scsi_level >= SCSI_2 &&
3131 ((STp->buffer)->b_data[0] & 4) != 0)) {
3132 *block = *partition = 0;
3133 DEBC_printk(STp, " Can't read tape position.\n");
3134 result = (-EIO);
3135 } else {
3136 result = 0;
3137 if ((STp->device)->scsi_level < SCSI_2) {
3138 *block = ((STp->buffer)->b_data[0] << 16)
3139 + ((STp->buffer)->b_data[1] << 8)
3140 + (STp->buffer)->b_data[2];
3141 *partition = 0;
3142 } else {
3143 *block = ((STp->buffer)->b_data[4] << 24)
3144 + ((STp->buffer)->b_data[5] << 16)
3145 + ((STp->buffer)->b_data[6] << 8)
3146 + (STp->buffer)->b_data[7];
3147 *partition = (STp->buffer)->b_data[1];
3148 if (((STp->buffer)->b_data[0] & 0x80) &&
3149 (STp->buffer)->b_data[1] == 0) /* BOP of partition 0 */
3150 STp->ps[0].drv_block = STp->ps[0].drv_file = 0;
3151 }
3152 DEBC_printk(STp, "Got tape pos. blk %d part %d.\n",
3153 *block, *partition);
3154 }
3155 st_release_request(SRpnt);
3156 SRpnt = NULL;
3157
3158 return result;
3159 }
3160
3161
3162 /* Set the tape block and partition. Negative partition means that only the
3163 block should be set in vendor specific way. */
set_location(struct scsi_tape * STp,unsigned int block,int partition,int logical)3164 static int set_location(struct scsi_tape *STp, unsigned int block, int partition,
3165 int logical)
3166 {
3167 struct st_partstat *STps;
3168 int result, p;
3169 unsigned int blk;
3170 int timeout;
3171 unsigned char scmd[MAX_COMMAND_SIZE];
3172 struct st_request *SRpnt;
3173
3174 if (STp->ready != ST_READY)
3175 return (-EIO);
3176 timeout = STp->long_timeout;
3177 STps = &(STp->ps[STp->partition]);
3178
3179 DEBC_printk(STp, "Setting block to %d and partition to %d.\n",
3180 block, partition);
3181 DEB(if (partition < 0)
3182 return (-EIO); )
3183
3184 /* Update the location at the partition we are leaving */
3185 if ((!STp->can_partitions && partition != 0) ||
3186 partition >= ST_NBR_PARTITIONS)
3187 return (-EINVAL);
3188 if (partition != STp->partition) {
3189 if (get_location(STp, &blk, &p, 1))
3190 STps->last_block_valid = 0;
3191 else {
3192 STps->last_block_valid = 1;
3193 STps->last_block_visited = blk;
3194 DEBC_printk(STp, "Visited block %d for "
3195 "partition %d saved.\n",
3196 blk, STp->partition);
3197 }
3198 }
3199
3200 memset(scmd, 0, MAX_COMMAND_SIZE);
3201 if ((STp->device)->scsi_level < SCSI_2) {
3202 scmd[0] = QFA_SEEK_BLOCK;
3203 scmd[2] = (block >> 16);
3204 scmd[3] = (block >> 8);
3205 scmd[4] = block;
3206 scmd[5] = 0;
3207 } else {
3208 scmd[0] = SEEK_10;
3209 scmd[3] = (block >> 24);
3210 scmd[4] = (block >> 16);
3211 scmd[5] = (block >> 8);
3212 scmd[6] = block;
3213 if (!logical && !STp->scsi2_logical)
3214 scmd[1] = 4;
3215 if (STp->partition != partition) {
3216 scmd[1] |= 2;
3217 scmd[8] = partition;
3218 DEBC_printk(STp, "Trying to change partition "
3219 "from %d to %d\n", STp->partition,
3220 partition);
3221 }
3222 }
3223 if (STp->immediate) {
3224 scmd[1] |= 1; /* Don't wait for completion */
3225 timeout = STp->device->request_queue->rq_timeout;
3226 }
3227
3228 SRpnt = st_do_scsi(NULL, STp, scmd, 0, DMA_NONE,
3229 timeout, MAX_READY_RETRIES, 1);
3230 if (!SRpnt)
3231 return (STp->buffer)->syscall_result;
3232
3233 STps->drv_block = STps->drv_file = (-1);
3234 STps->eof = ST_NOEOF;
3235 if ((STp->buffer)->syscall_result != 0) {
3236 result = (-EIO);
3237 if (STp->can_partitions &&
3238 (STp->device)->scsi_level >= SCSI_2 &&
3239 (p = find_partition(STp)) >= 0)
3240 STp->partition = p;
3241 } else {
3242 if (STp->can_partitions) {
3243 STp->partition = partition;
3244 STps = &(STp->ps[partition]);
3245 if (!STps->last_block_valid ||
3246 STps->last_block_visited != block) {
3247 STps->at_sm = 0;
3248 STps->rw = ST_IDLE;
3249 }
3250 } else
3251 STps->at_sm = 0;
3252 if (block == 0)
3253 STps->drv_block = STps->drv_file = 0;
3254 result = 0;
3255 }
3256
3257 st_release_request(SRpnt);
3258 SRpnt = NULL;
3259
3260 return result;
3261 }
3262
3263
3264 /* Find the current partition number for the drive status. Called from open and
3265 returns either partition number of negative error code. */
find_partition(struct scsi_tape * STp)3266 static int find_partition(struct scsi_tape *STp)
3267 {
3268 int i, partition;
3269 unsigned int block;
3270
3271 if ((i = get_location(STp, &block, &partition, 1)) < 0)
3272 return i;
3273 if (partition >= ST_NBR_PARTITIONS)
3274 return (-EIO);
3275 return partition;
3276 }
3277
3278
3279 /* Change the partition if necessary */
switch_partition(struct scsi_tape * STp)3280 static int switch_partition(struct scsi_tape *STp)
3281 {
3282 struct st_partstat *STps;
3283
3284 if (STp->partition == STp->new_partition)
3285 return 0;
3286 STps = &(STp->ps[STp->new_partition]);
3287 if (!STps->last_block_valid)
3288 STps->last_block_visited = 0;
3289 return set_location(STp, STps->last_block_visited, STp->new_partition, 1);
3290 }
3291
3292 /* Functions for reading and writing the medium partition mode page. */
3293
3294 #define PART_PAGE 0x11
3295 #define PART_PAGE_FIXED_LENGTH 8
3296
3297 #define PP_OFF_MAX_ADD_PARTS 2
3298 #define PP_OFF_NBR_ADD_PARTS 3
3299 #define PP_OFF_FLAGS 4
3300 #define PP_OFF_PART_UNITS 6
3301 #define PP_OFF_RESERVED 7
3302
3303 #define PP_BIT_IDP 0x20
3304 #define PP_BIT_FDP 0x80
3305 #define PP_MSK_PSUM_MB 0x10
3306 #define PP_MSK_PSUM_UNITS 0x18
3307 #define PP_MSK_POFM 0x04
3308
3309 /* Get the number of partitions on the tape. As a side effect reads the
3310 mode page into the tape buffer. */
nbr_partitions(struct scsi_tape * STp)3311 static int nbr_partitions(struct scsi_tape *STp)
3312 {
3313 int result;
3314
3315 if (STp->ready != ST_READY)
3316 return (-EIO);
3317
3318 result = read_mode_page(STp, PART_PAGE, 1);
3319
3320 if (result) {
3321 DEBC_printk(STp, "Can't read medium partition page.\n");
3322 result = (-EIO);
3323 } else {
3324 result = (STp->buffer)->b_data[MODE_HEADER_LENGTH +
3325 PP_OFF_NBR_ADD_PARTS] + 1;
3326 DEBC_printk(STp, "Number of partitions %d.\n", result);
3327 }
3328
3329 return result;
3330 }
3331
3332
format_medium(struct scsi_tape * STp,int format)3333 static int format_medium(struct scsi_tape *STp, int format)
3334 {
3335 int result = 0;
3336 int timeout = STp->long_timeout;
3337 unsigned char scmd[MAX_COMMAND_SIZE];
3338 struct st_request *SRpnt;
3339
3340 memset(scmd, 0, MAX_COMMAND_SIZE);
3341 scmd[0] = FORMAT_UNIT;
3342 scmd[2] = format;
3343 if (STp->immediate) {
3344 scmd[1] |= 1; /* Don't wait for completion */
3345 timeout = STp->device->request_queue->rq_timeout;
3346 }
3347 DEBC_printk(STp, "Sending FORMAT MEDIUM\n");
3348 SRpnt = st_do_scsi(NULL, STp, scmd, 0, DMA_NONE,
3349 timeout, MAX_RETRIES, 1);
3350 if (!SRpnt)
3351 result = STp->buffer->syscall_result;
3352 return result;
3353 }
3354
3355
3356 /* Partition the tape into two partitions if size > 0 or one partition if
3357 size == 0.
3358
3359 The block descriptors are read and written because Sony SDT-7000 does not
3360 work without this (suggestion from Michael Schaefer <Michael.Schaefer@dlr.de>).
3361
3362 My HP C1533A drive returns only one partition size field. This is used to
3363 set the size of partition 1. There is no size field for the default partition.
3364 Michael Schaefer's Sony SDT-7000 returns two descriptors and the second is
3365 used to set the size of partition 1 (this is what the SCSI-3 standard specifies).
3366 The following algorithm is used to accommodate both drives: if the number of
3367 partition size fields is greater than the maximum number of additional partitions
3368 in the mode page, the second field is used. Otherwise the first field is used.
3369
3370 For Seagate DDS drives the page length must be 8 when no partitions is defined
3371 and 10 when 1 partition is defined (information from Eric Lee Green). This is
3372 is acceptable also to some other old drives and enforced if the first partition
3373 size field is used for the first additional partition size.
3374
3375 For drives that advertize SCSI-3 or newer, use the SSC-3 methods.
3376 */
partition_tape(struct scsi_tape * STp,int size)3377 static int partition_tape(struct scsi_tape *STp, int size)
3378 {
3379 int result;
3380 int target_partition;
3381 bool scsi3 = STp->device->scsi_level >= SCSI_3, needs_format = false;
3382 int pgo, psd_cnt, psdo;
3383 int psum = PP_MSK_PSUM_MB, units = 0;
3384 unsigned char *bp;
3385
3386 result = read_mode_page(STp, PART_PAGE, 0);
3387 if (result) {
3388 DEBC_printk(STp, "Can't read partition mode page.\n");
3389 return result;
3390 }
3391 target_partition = 1;
3392 if (size < 0) {
3393 target_partition = 0;
3394 size = -size;
3395 }
3396
3397 /* The mode page is in the buffer. Let's modify it and write it. */
3398 bp = (STp->buffer)->b_data;
3399 pgo = MODE_HEADER_LENGTH + bp[MH_OFF_BDESCS_LENGTH];
3400 DEBC_printk(STp, "Partition page length is %d bytes.\n",
3401 bp[pgo + MP_OFF_PAGE_LENGTH] + 2);
3402
3403 psd_cnt = (bp[pgo + MP_OFF_PAGE_LENGTH] + 2 - PART_PAGE_FIXED_LENGTH) / 2;
3404
3405 if (scsi3) {
3406 needs_format = (bp[pgo + PP_OFF_FLAGS] & PP_MSK_POFM) != 0;
3407 if (needs_format && size == 0) {
3408 /* No need to write the mode page when clearing
3409 * partitioning
3410 */
3411 DEBC_printk(STp, "Formatting tape with one partition.\n");
3412 result = format_medium(STp, 0);
3413 goto out;
3414 }
3415 if (needs_format) /* Leave the old value for HP DATs claiming SCSI_3 */
3416 psd_cnt = 2;
3417 if ((bp[pgo + PP_OFF_FLAGS] & PP_MSK_PSUM_UNITS) == PP_MSK_PSUM_UNITS) {
3418 /* Use units scaling for large partitions if the device
3419 * suggests it and no precision lost. Required for IBM
3420 * TS1140/50 drives that don't support MB units.
3421 */
3422 if (size >= 1000 && (size % 1000) == 0) {
3423 size /= 1000;
3424 psum = PP_MSK_PSUM_UNITS;
3425 units = 9; /* GB */
3426 }
3427 }
3428 /* Try it anyway if too large to specify in MB */
3429 if (psum == PP_MSK_PSUM_MB && size >= 65534) {
3430 size /= 1000;
3431 psum = PP_MSK_PSUM_UNITS;
3432 units = 9; /* GB */
3433 }
3434 }
3435
3436 if (size >= 65535 || /* Does not fit into two bytes */
3437 (target_partition == 0 && psd_cnt < 2)) {
3438 result = -EINVAL;
3439 goto out;
3440 }
3441
3442 psdo = pgo + PART_PAGE_FIXED_LENGTH;
3443 /* The second condition is for HP DDS which use only one partition size
3444 * descriptor
3445 */
3446 if (target_partition > 0 &&
3447 (psd_cnt > bp[pgo + PP_OFF_MAX_ADD_PARTS] ||
3448 bp[pgo + PP_OFF_MAX_ADD_PARTS] != 1)) {
3449 bp[psdo] = bp[psdo + 1] = 0xff; /* Rest to partition 0 */
3450 psdo += 2;
3451 }
3452 memset(bp + psdo, 0, bp[pgo + PP_OFF_NBR_ADD_PARTS] * 2);
3453
3454 DEBC_printk(STp, "psd_cnt %d, max.parts %d, nbr_parts %d\n",
3455 psd_cnt, bp[pgo + PP_OFF_MAX_ADD_PARTS],
3456 bp[pgo + PP_OFF_NBR_ADD_PARTS]);
3457
3458 if (size == 0) {
3459 bp[pgo + PP_OFF_NBR_ADD_PARTS] = 0;
3460 if (psd_cnt <= bp[pgo + PP_OFF_MAX_ADD_PARTS])
3461 bp[pgo + MP_OFF_PAGE_LENGTH] = 6;
3462 DEBC_printk(STp, "Formatting tape with one partition.\n");
3463 } else {
3464 bp[psdo] = (size >> 8) & 0xff;
3465 bp[psdo + 1] = size & 0xff;
3466 if (target_partition == 0)
3467 bp[psdo + 2] = bp[psdo + 3] = 0xff;
3468 bp[pgo + 3] = 1;
3469 if (bp[pgo + MP_OFF_PAGE_LENGTH] < 8)
3470 bp[pgo + MP_OFF_PAGE_LENGTH] = 8;
3471 DEBC_printk(STp,
3472 "Formatting tape with two partitions (%i = %d MB).\n",
3473 target_partition, units > 0 ? size * 1000 : size);
3474 }
3475 bp[pgo + PP_OFF_PART_UNITS] = 0;
3476 bp[pgo + PP_OFF_RESERVED] = 0;
3477 if (size != 1 || units != 0) {
3478 bp[pgo + PP_OFF_FLAGS] = PP_BIT_IDP | psum |
3479 (bp[pgo + PP_OFF_FLAGS] & 0x07);
3480 bp[pgo + PP_OFF_PART_UNITS] = units;
3481 } else
3482 bp[pgo + PP_OFF_FLAGS] = PP_BIT_FDP |
3483 (bp[pgo + PP_OFF_FLAGS] & 0x1f);
3484 bp[pgo + MP_OFF_PAGE_LENGTH] = 6 + psd_cnt * 2;
3485
3486 result = write_mode_page(STp, PART_PAGE, 1);
3487
3488 if (!result && needs_format)
3489 result = format_medium(STp, 1);
3490
3491 if (result) {
3492 st_printk(KERN_INFO, STp, "Partitioning of tape failed.\n");
3493 result = (-EIO);
3494 }
3495
3496 out:
3497 return result;
3498 }
3499
3500
3501
3502 /* The ioctl command */
st_ioctl(struct file * file,unsigned int cmd_in,unsigned long arg)3503 static long st_ioctl(struct file *file, unsigned int cmd_in, unsigned long arg)
3504 {
3505 int i, cmd_nr, cmd_type, bt;
3506 int retval = 0;
3507 unsigned int blk;
3508 struct scsi_tape *STp = file->private_data;
3509 struct st_modedef *STm;
3510 struct st_partstat *STps;
3511 void __user *p = (void __user *)arg;
3512
3513 if (mutex_lock_interruptible(&STp->lock))
3514 return -ERESTARTSYS;
3515
3516 DEB(
3517 if (debugging && !STp->in_use) {
3518 st_printk(ST_DEB_MSG, STp, "Incorrect device.\n");
3519 retval = (-EIO);
3520 goto out;
3521 } ) /* end DEB */
3522
3523 STm = &(STp->modes[STp->current_mode]);
3524 STps = &(STp->ps[STp->partition]);
3525
3526 /*
3527 * If we are in the middle of error recovery, don't let anyone
3528 * else try and use this device. Also, if error recovery fails, it
3529 * may try and take the device offline, in which case all further
3530 * access to the device is prohibited.
3531 */
3532 retval = scsi_ioctl_block_when_processing_errors(STp->device, cmd_in,
3533 file->f_flags & O_NDELAY);
3534 if (retval)
3535 goto out;
3536
3537 cmd_type = _IOC_TYPE(cmd_in);
3538 cmd_nr = _IOC_NR(cmd_in);
3539
3540 if (cmd_type == _IOC_TYPE(MTIOCTOP) && cmd_nr == _IOC_NR(MTIOCTOP)) {
3541 struct mtop mtc;
3542
3543 if (_IOC_SIZE(cmd_in) != sizeof(mtc)) {
3544 retval = (-EINVAL);
3545 goto out;
3546 }
3547
3548 i = copy_from_user(&mtc, p, sizeof(struct mtop));
3549 if (i) {
3550 retval = (-EFAULT);
3551 goto out;
3552 }
3553
3554 if (mtc.mt_op == MTSETDRVBUFFER && !capable(CAP_SYS_ADMIN)) {
3555 st_printk(KERN_WARNING, STp,
3556 "MTSETDRVBUFFER only allowed for root.\n");
3557 retval = (-EPERM);
3558 goto out;
3559 }
3560 if (!STm->defined &&
3561 (mtc.mt_op != MTSETDRVBUFFER &&
3562 (mtc.mt_count & MT_ST_OPTIONS) == 0)) {
3563 retval = (-ENXIO);
3564 goto out;
3565 }
3566
3567 if (!STp->pos_unknown) {
3568
3569 if (STps->eof == ST_FM_HIT) {
3570 if (mtc.mt_op == MTFSF || mtc.mt_op == MTFSFM ||
3571 mtc.mt_op == MTEOM) {
3572 mtc.mt_count -= 1;
3573 if (STps->drv_file >= 0)
3574 STps->drv_file += 1;
3575 } else if (mtc.mt_op == MTBSF || mtc.mt_op == MTBSFM) {
3576 mtc.mt_count += 1;
3577 if (STps->drv_file >= 0)
3578 STps->drv_file += 1;
3579 }
3580 }
3581
3582 if (mtc.mt_op == MTSEEK) {
3583 /* Old position must be restored if partition will be
3584 changed */
3585 i = !STp->can_partitions ||
3586 (STp->new_partition != STp->partition);
3587 } else {
3588 i = mtc.mt_op == MTREW || mtc.mt_op == MTOFFL ||
3589 mtc.mt_op == MTRETEN || mtc.mt_op == MTEOM ||
3590 mtc.mt_op == MTLOCK || mtc.mt_op == MTLOAD ||
3591 mtc.mt_op == MTFSF || mtc.mt_op == MTFSFM ||
3592 mtc.mt_op == MTBSF || mtc.mt_op == MTBSFM ||
3593 mtc.mt_op == MTCOMPRESSION;
3594 }
3595 i = flush_buffer(STp, i);
3596 if (i < 0) {
3597 retval = i;
3598 goto out;
3599 }
3600 if (STps->rw == ST_WRITING &&
3601 (mtc.mt_op == MTREW || mtc.mt_op == MTOFFL ||
3602 mtc.mt_op == MTSEEK ||
3603 mtc.mt_op == MTBSF || mtc.mt_op == MTBSFM)) {
3604 i = st_int_ioctl(STp, MTWEOF, 1);
3605 if (i < 0) {
3606 retval = i;
3607 goto out;
3608 }
3609 if (mtc.mt_op == MTBSF || mtc.mt_op == MTBSFM)
3610 mtc.mt_count++;
3611 STps->rw = ST_IDLE;
3612 }
3613
3614 } else {
3615 /*
3616 * If there was a bus reset, block further access
3617 * to this device. If the user wants to rewind the tape,
3618 * then reset the flag and allow access again.
3619 */
3620 if (mtc.mt_op != MTREW &&
3621 mtc.mt_op != MTOFFL &&
3622 mtc.mt_op != MTRETEN &&
3623 mtc.mt_op != MTERASE &&
3624 mtc.mt_op != MTSEEK &&
3625 mtc.mt_op != MTEOM) {
3626 retval = (-EIO);
3627 goto out;
3628 }
3629 reset_state(STp);
3630 /* remove this when the midlevel properly clears was_reset */
3631 STp->device->was_reset = 0;
3632 }
3633
3634 if (mtc.mt_op != MTNOP && mtc.mt_op != MTSETBLK &&
3635 mtc.mt_op != MTSETDENSITY && mtc.mt_op != MTWSM &&
3636 mtc.mt_op != MTSETDRVBUFFER && mtc.mt_op != MTSETPART)
3637 STps->rw = ST_IDLE; /* Prevent automatic WEOF and fsf */
3638
3639 if (mtc.mt_op == MTOFFL && STp->door_locked != ST_UNLOCKED)
3640 do_door_lock(STp, 0); /* Ignore result! */
3641
3642 if (mtc.mt_op == MTSETDRVBUFFER &&
3643 (mtc.mt_count & MT_ST_OPTIONS) != 0) {
3644 retval = st_set_options(STp, mtc.mt_count);
3645 goto out;
3646 }
3647
3648 if (mtc.mt_op == MTSETPART) {
3649 if (!STp->can_partitions ||
3650 mtc.mt_count < 0 || mtc.mt_count >= ST_NBR_PARTITIONS) {
3651 retval = (-EINVAL);
3652 goto out;
3653 }
3654 if (mtc.mt_count >= STp->nbr_partitions &&
3655 (STp->nbr_partitions = nbr_partitions(STp)) < 0) {
3656 retval = (-EIO);
3657 goto out;
3658 }
3659 if (mtc.mt_count >= STp->nbr_partitions) {
3660 retval = (-EINVAL);
3661 goto out;
3662 }
3663 STp->new_partition = mtc.mt_count;
3664 retval = 0;
3665 goto out;
3666 }
3667
3668 if (mtc.mt_op == MTMKPART) {
3669 if (!STp->can_partitions) {
3670 retval = (-EINVAL);
3671 goto out;
3672 }
3673 i = do_load_unload(STp, file, 1);
3674 if (i < 0) {
3675 retval = i;
3676 goto out;
3677 }
3678 i = partition_tape(STp, mtc.mt_count);
3679 if (i < 0) {
3680 retval = i;
3681 goto out;
3682 }
3683 for (i = 0; i < ST_NBR_PARTITIONS; i++) {
3684 STp->ps[i].rw = ST_IDLE;
3685 STp->ps[i].at_sm = 0;
3686 STp->ps[i].last_block_valid = 0;
3687 }
3688 STp->partition = STp->new_partition = 0;
3689 STp->nbr_partitions = mtc.mt_count != 0 ? 2 : 1;
3690 STps->drv_block = STps->drv_file = 0;
3691 retval = 0;
3692 goto out;
3693 }
3694
3695 if (mtc.mt_op == MTSEEK) {
3696 i = set_location(STp, mtc.mt_count, STp->new_partition, 0);
3697 if (!STp->can_partitions)
3698 STp->ps[0].rw = ST_IDLE;
3699 retval = i;
3700 goto out;
3701 }
3702
3703 if (mtc.mt_op == MTUNLOAD || mtc.mt_op == MTOFFL) {
3704 retval = do_load_unload(STp, file, 0);
3705 goto out;
3706 }
3707
3708 if (mtc.mt_op == MTLOAD) {
3709 retval = do_load_unload(STp, file, max(1, mtc.mt_count));
3710 goto out;
3711 }
3712
3713 if (mtc.mt_op == MTLOCK || mtc.mt_op == MTUNLOCK) {
3714 retval = do_door_lock(STp, (mtc.mt_op == MTLOCK));
3715 goto out;
3716 }
3717
3718 if (STp->can_partitions && STp->ready == ST_READY &&
3719 (i = switch_partition(STp)) < 0) {
3720 retval = i;
3721 goto out;
3722 }
3723
3724 if (mtc.mt_op == MTCOMPRESSION)
3725 retval = st_compression(STp, (mtc.mt_count & 1));
3726 else
3727 retval = st_int_ioctl(STp, mtc.mt_op, mtc.mt_count);
3728 goto out;
3729 }
3730 if (!STm->defined) {
3731 retval = (-ENXIO);
3732 goto out;
3733 }
3734
3735 if ((i = flush_buffer(STp, 0)) < 0) {
3736 retval = i;
3737 goto out;
3738 }
3739 if (STp->can_partitions &&
3740 (i = switch_partition(STp)) < 0) {
3741 retval = i;
3742 goto out;
3743 }
3744
3745 if (cmd_type == _IOC_TYPE(MTIOCGET) && cmd_nr == _IOC_NR(MTIOCGET)) {
3746 struct mtget mt_status;
3747
3748 if (_IOC_SIZE(cmd_in) != sizeof(struct mtget)) {
3749 retval = (-EINVAL);
3750 goto out;
3751 }
3752
3753 mt_status.mt_type = STp->tape_type;
3754 mt_status.mt_dsreg =
3755 ((STp->block_size << MT_ST_BLKSIZE_SHIFT) & MT_ST_BLKSIZE_MASK) |
3756 ((STp->density << MT_ST_DENSITY_SHIFT) & MT_ST_DENSITY_MASK);
3757 mt_status.mt_blkno = STps->drv_block;
3758 mt_status.mt_fileno = STps->drv_file;
3759 if (STp->block_size != 0) {
3760 if (STps->rw == ST_WRITING)
3761 mt_status.mt_blkno +=
3762 (STp->buffer)->buffer_bytes / STp->block_size;
3763 else if (STps->rw == ST_READING)
3764 mt_status.mt_blkno -=
3765 ((STp->buffer)->buffer_bytes +
3766 STp->block_size - 1) / STp->block_size;
3767 }
3768
3769 mt_status.mt_gstat = 0;
3770 if (STp->drv_write_prot)
3771 mt_status.mt_gstat |= GMT_WR_PROT(0xffffffff);
3772 if (mt_status.mt_blkno == 0) {
3773 if (mt_status.mt_fileno == 0)
3774 mt_status.mt_gstat |= GMT_BOT(0xffffffff);
3775 else
3776 mt_status.mt_gstat |= GMT_EOF(0xffffffff);
3777 }
3778 mt_status.mt_erreg = (STp->recover_reg << MT_ST_SOFTERR_SHIFT);
3779 mt_status.mt_resid = STp->partition;
3780 if (STps->eof == ST_EOM_OK || STps->eof == ST_EOM_ERROR)
3781 mt_status.mt_gstat |= GMT_EOT(0xffffffff);
3782 else if (STps->eof >= ST_EOM_OK)
3783 mt_status.mt_gstat |= GMT_EOD(0xffffffff);
3784 if (STp->density == 1)
3785 mt_status.mt_gstat |= GMT_D_800(0xffffffff);
3786 else if (STp->density == 2)
3787 mt_status.mt_gstat |= GMT_D_1600(0xffffffff);
3788 else if (STp->density == 3)
3789 mt_status.mt_gstat |= GMT_D_6250(0xffffffff);
3790 if (STp->ready == ST_READY)
3791 mt_status.mt_gstat |= GMT_ONLINE(0xffffffff);
3792 if (STp->ready == ST_NO_TAPE)
3793 mt_status.mt_gstat |= GMT_DR_OPEN(0xffffffff);
3794 if (STps->at_sm)
3795 mt_status.mt_gstat |= GMT_SM(0xffffffff);
3796 if (STm->do_async_writes ||
3797 (STm->do_buffer_writes && STp->block_size != 0) ||
3798 STp->drv_buffer != 0)
3799 mt_status.mt_gstat |= GMT_IM_REP_EN(0xffffffff);
3800 if (STp->cleaning_req)
3801 mt_status.mt_gstat |= GMT_CLN(0xffffffff);
3802
3803 i = copy_to_user(p, &mt_status, sizeof(struct mtget));
3804 if (i) {
3805 retval = (-EFAULT);
3806 goto out;
3807 }
3808
3809 STp->recover_reg = 0; /* Clear after read */
3810 retval = 0;
3811 goto out;
3812 } /* End of MTIOCGET */
3813 if (cmd_type == _IOC_TYPE(MTIOCPOS) && cmd_nr == _IOC_NR(MTIOCPOS)) {
3814 struct mtpos mt_pos;
3815 if (_IOC_SIZE(cmd_in) != sizeof(struct mtpos)) {
3816 retval = (-EINVAL);
3817 goto out;
3818 }
3819 if ((i = get_location(STp, &blk, &bt, 0)) < 0) {
3820 retval = i;
3821 goto out;
3822 }
3823 mt_pos.mt_blkno = blk;
3824 i = copy_to_user(p, &mt_pos, sizeof(struct mtpos));
3825 if (i)
3826 retval = (-EFAULT);
3827 goto out;
3828 }
3829 mutex_unlock(&STp->lock);
3830 switch (cmd_in) {
3831 case SCSI_IOCTL_GET_IDLUN:
3832 case SCSI_IOCTL_GET_BUS_NUMBER:
3833 break;
3834 default:
3835 if ((cmd_in == SG_IO ||
3836 cmd_in == SCSI_IOCTL_SEND_COMMAND ||
3837 cmd_in == CDROM_SEND_PACKET) &&
3838 !capable(CAP_SYS_RAWIO))
3839 i = -EPERM;
3840 else
3841 i = scsi_cmd_ioctl(STp->disk->queue, STp->disk,
3842 file->f_mode, cmd_in, p);
3843 if (i != -ENOTTY)
3844 return i;
3845 break;
3846 }
3847 retval = scsi_ioctl(STp->device, cmd_in, p);
3848 if (!retval && cmd_in == SCSI_IOCTL_STOP_UNIT) { /* unload */
3849 STp->rew_at_close = 0;
3850 STp->ready = ST_NO_TAPE;
3851 }
3852 return retval;
3853
3854 out:
3855 mutex_unlock(&STp->lock);
3856 return retval;
3857 }
3858
3859 #ifdef CONFIG_COMPAT
st_compat_ioctl(struct file * file,unsigned int cmd,unsigned long arg)3860 static long st_compat_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
3861 {
3862 struct scsi_tape *STp = file->private_data;
3863 struct scsi_device *sdev = STp->device;
3864 int ret = -ENOIOCTLCMD;
3865 if (sdev->host->hostt->compat_ioctl) {
3866
3867 ret = sdev->host->hostt->compat_ioctl(sdev, cmd, (void __user *)arg);
3868
3869 }
3870 return ret;
3871 }
3872 #endif
3873
3874
3875
3876 /* Try to allocate a new tape buffer. Calling function must not hold
3877 dev_arr_lock. */
new_tape_buffer(int need_dma,int max_sg)3878 static struct st_buffer *new_tape_buffer(int need_dma, int max_sg)
3879 {
3880 struct st_buffer *tb;
3881
3882 tb = kzalloc(sizeof(struct st_buffer), GFP_KERNEL);
3883 if (!tb) {
3884 printk(KERN_NOTICE "st: Can't allocate new tape buffer.\n");
3885 return NULL;
3886 }
3887 tb->frp_segs = 0;
3888 tb->use_sg = max_sg;
3889 tb->dma = need_dma;
3890 tb->buffer_size = 0;
3891
3892 tb->reserved_pages = kcalloc(max_sg, sizeof(struct page *),
3893 GFP_KERNEL);
3894 if (!tb->reserved_pages) {
3895 kfree(tb);
3896 return NULL;
3897 }
3898
3899 return tb;
3900 }
3901
3902
3903 /* Try to allocate enough space in the tape buffer */
3904 #define ST_MAX_ORDER 6
3905
enlarge_buffer(struct st_buffer * STbuffer,int new_size,int need_dma)3906 static int enlarge_buffer(struct st_buffer * STbuffer, int new_size, int need_dma)
3907 {
3908 int segs, max_segs, b_size, order, got;
3909 gfp_t priority;
3910
3911 if (new_size <= STbuffer->buffer_size)
3912 return 1;
3913
3914 if (STbuffer->buffer_size <= PAGE_SIZE)
3915 normalize_buffer(STbuffer); /* Avoid extra segment */
3916
3917 max_segs = STbuffer->use_sg;
3918
3919 priority = GFP_KERNEL | __GFP_NOWARN;
3920 if (need_dma)
3921 priority |= GFP_DMA;
3922
3923 if (STbuffer->cleared)
3924 priority |= __GFP_ZERO;
3925
3926 if (STbuffer->frp_segs) {
3927 order = STbuffer->reserved_page_order;
3928 b_size = PAGE_SIZE << order;
3929 } else {
3930 for (b_size = PAGE_SIZE, order = 0;
3931 order < ST_MAX_ORDER &&
3932 max_segs * (PAGE_SIZE << order) < new_size;
3933 order++, b_size *= 2)
3934 ; /* empty */
3935 STbuffer->reserved_page_order = order;
3936 }
3937 if (max_segs * (PAGE_SIZE << order) < new_size) {
3938 if (order == ST_MAX_ORDER)
3939 return 0;
3940 normalize_buffer(STbuffer);
3941 return enlarge_buffer(STbuffer, new_size, need_dma);
3942 }
3943
3944 for (segs = STbuffer->frp_segs, got = STbuffer->buffer_size;
3945 segs < max_segs && got < new_size;) {
3946 struct page *page;
3947
3948 page = alloc_pages(priority, order);
3949 if (!page) {
3950 DEB(STbuffer->buffer_size = got);
3951 normalize_buffer(STbuffer);
3952 return 0;
3953 }
3954
3955 STbuffer->frp_segs += 1;
3956 got += b_size;
3957 STbuffer->buffer_size = got;
3958 STbuffer->reserved_pages[segs] = page;
3959 segs++;
3960 }
3961 STbuffer->b_data = page_address(STbuffer->reserved_pages[0]);
3962
3963 return 1;
3964 }
3965
3966
3967 /* Make sure that no data from previous user is in the internal buffer */
clear_buffer(struct st_buffer * st_bp)3968 static void clear_buffer(struct st_buffer * st_bp)
3969 {
3970 int i;
3971
3972 for (i=0; i < st_bp->frp_segs; i++)
3973 memset(page_address(st_bp->reserved_pages[i]), 0,
3974 PAGE_SIZE << st_bp->reserved_page_order);
3975 st_bp->cleared = 1;
3976 }
3977
3978
3979 /* Release the extra buffer */
normalize_buffer(struct st_buffer * STbuffer)3980 static void normalize_buffer(struct st_buffer * STbuffer)
3981 {
3982 int i, order = STbuffer->reserved_page_order;
3983
3984 for (i = 0; i < STbuffer->frp_segs; i++) {
3985 __free_pages(STbuffer->reserved_pages[i], order);
3986 STbuffer->buffer_size -= (PAGE_SIZE << order);
3987 }
3988 STbuffer->frp_segs = 0;
3989 STbuffer->sg_segs = 0;
3990 STbuffer->reserved_page_order = 0;
3991 STbuffer->map_data.offset = 0;
3992 }
3993
3994
3995 /* Move data from the user buffer to the tape buffer. Returns zero (success) or
3996 negative error code. */
append_to_buffer(const char __user * ubp,struct st_buffer * st_bp,int do_count)3997 static int append_to_buffer(const char __user *ubp, struct st_buffer * st_bp, int do_count)
3998 {
3999 int i, cnt, res, offset;
4000 int length = PAGE_SIZE << st_bp->reserved_page_order;
4001
4002 for (i = 0, offset = st_bp->buffer_bytes;
4003 i < st_bp->frp_segs && offset >= length; i++)
4004 offset -= length;
4005 if (i == st_bp->frp_segs) { /* Should never happen */
4006 printk(KERN_WARNING "st: append_to_buffer offset overflow.\n");
4007 return (-EIO);
4008 }
4009 for (; i < st_bp->frp_segs && do_count > 0; i++) {
4010 struct page *page = st_bp->reserved_pages[i];
4011 cnt = length - offset < do_count ? length - offset : do_count;
4012 res = copy_from_user(page_address(page) + offset, ubp, cnt);
4013 if (res)
4014 return (-EFAULT);
4015 do_count -= cnt;
4016 st_bp->buffer_bytes += cnt;
4017 ubp += cnt;
4018 offset = 0;
4019 }
4020 if (do_count) /* Should never happen */
4021 return (-EIO);
4022
4023 return 0;
4024 }
4025
4026
4027 /* Move data from the tape buffer to the user buffer. Returns zero (success) or
4028 negative error code. */
from_buffer(struct st_buffer * st_bp,char __user * ubp,int do_count)4029 static int from_buffer(struct st_buffer * st_bp, char __user *ubp, int do_count)
4030 {
4031 int i, cnt, res, offset;
4032 int length = PAGE_SIZE << st_bp->reserved_page_order;
4033
4034 for (i = 0, offset = st_bp->read_pointer;
4035 i < st_bp->frp_segs && offset >= length; i++)
4036 offset -= length;
4037 if (i == st_bp->frp_segs) { /* Should never happen */
4038 printk(KERN_WARNING "st: from_buffer offset overflow.\n");
4039 return (-EIO);
4040 }
4041 for (; i < st_bp->frp_segs && do_count > 0; i++) {
4042 struct page *page = st_bp->reserved_pages[i];
4043 cnt = length - offset < do_count ? length - offset : do_count;
4044 res = copy_to_user(ubp, page_address(page) + offset, cnt);
4045 if (res)
4046 return (-EFAULT);
4047 do_count -= cnt;
4048 st_bp->buffer_bytes -= cnt;
4049 st_bp->read_pointer += cnt;
4050 ubp += cnt;
4051 offset = 0;
4052 }
4053 if (do_count) /* Should never happen */
4054 return (-EIO);
4055
4056 return 0;
4057 }
4058
4059
4060 /* Move data towards start of buffer */
move_buffer_data(struct st_buffer * st_bp,int offset)4061 static void move_buffer_data(struct st_buffer * st_bp, int offset)
4062 {
4063 int src_seg, dst_seg, src_offset = 0, dst_offset;
4064 int count, total;
4065 int length = PAGE_SIZE << st_bp->reserved_page_order;
4066
4067 if (offset == 0)
4068 return;
4069
4070 total=st_bp->buffer_bytes - offset;
4071 for (src_seg=0; src_seg < st_bp->frp_segs; src_seg++) {
4072 src_offset = offset;
4073 if (src_offset < length)
4074 break;
4075 offset -= length;
4076 }
4077
4078 st_bp->buffer_bytes = st_bp->read_pointer = total;
4079 for (dst_seg=dst_offset=0; total > 0; ) {
4080 struct page *dpage = st_bp->reserved_pages[dst_seg];
4081 struct page *spage = st_bp->reserved_pages[src_seg];
4082
4083 count = min(length - dst_offset, length - src_offset);
4084 memmove(page_address(dpage) + dst_offset,
4085 page_address(spage) + src_offset, count);
4086 src_offset += count;
4087 if (src_offset >= length) {
4088 src_seg++;
4089 src_offset = 0;
4090 }
4091 dst_offset += count;
4092 if (dst_offset >= length) {
4093 dst_seg++;
4094 dst_offset = 0;
4095 }
4096 total -= count;
4097 }
4098 }
4099
4100 /* Validate the options from command line or module parameters */
validate_options(void)4101 static void validate_options(void)
4102 {
4103 if (buffer_kbs > 0)
4104 st_fixed_buffer_size = buffer_kbs * ST_KILOBYTE;
4105 if (max_sg_segs >= ST_FIRST_SG)
4106 st_max_sg_segs = max_sg_segs;
4107 }
4108
4109 #ifndef MODULE
4110 /* Set the boot options. Syntax is defined in Documenation/scsi/st.txt.
4111 */
st_setup(char * str)4112 static int __init st_setup(char *str)
4113 {
4114 int i, len, ints[5];
4115 char *stp;
4116
4117 stp = get_options(str, ARRAY_SIZE(ints), ints);
4118
4119 if (ints[0] > 0) {
4120 for (i = 0; i < ints[0] && i < ARRAY_SIZE(parms); i++)
4121 if (parms[i].val)
4122 *parms[i].val = ints[i + 1];
4123 } else {
4124 while (stp != NULL) {
4125 for (i = 0; i < ARRAY_SIZE(parms); i++) {
4126 len = strlen(parms[i].name);
4127 if (!strncmp(stp, parms[i].name, len) &&
4128 (*(stp + len) == ':' || *(stp + len) == '=')) {
4129 if (parms[i].val)
4130 *parms[i].val =
4131 simple_strtoul(stp + len + 1, NULL, 0);
4132 else
4133 printk(KERN_WARNING "st: Obsolete parameter %s\n",
4134 parms[i].name);
4135 break;
4136 }
4137 }
4138 if (i >= ARRAY_SIZE(parms))
4139 printk(KERN_WARNING "st: invalid parameter in '%s'\n",
4140 stp);
4141 stp = strchr(stp, ',');
4142 if (stp)
4143 stp++;
4144 }
4145 }
4146
4147 validate_options();
4148
4149 return 1;
4150 }
4151
4152 __setup("st=", st_setup);
4153
4154 #endif
4155
4156 static const struct file_operations st_fops =
4157 {
4158 .owner = THIS_MODULE,
4159 .read = st_read,
4160 .write = st_write,
4161 .unlocked_ioctl = st_ioctl,
4162 #ifdef CONFIG_COMPAT
4163 .compat_ioctl = st_compat_ioctl,
4164 #endif
4165 .open = st_open,
4166 .flush = st_flush,
4167 .release = st_release,
4168 .llseek = noop_llseek,
4169 };
4170
create_one_cdev(struct scsi_tape * tape,int mode,int rew)4171 static int create_one_cdev(struct scsi_tape *tape, int mode, int rew)
4172 {
4173 int i, error;
4174 dev_t cdev_devno;
4175 struct cdev *cdev;
4176 struct device *dev;
4177 struct st_modedef *STm = &(tape->modes[mode]);
4178 char name[10];
4179 int dev_num = tape->index;
4180
4181 cdev_devno = MKDEV(SCSI_TAPE_MAJOR, TAPE_MINOR(dev_num, mode, rew));
4182
4183 cdev = cdev_alloc();
4184 if (!cdev) {
4185 pr_err("st%d: out of memory. Device not attached.\n", dev_num);
4186 error = -ENOMEM;
4187 goto out;
4188 }
4189 cdev->owner = THIS_MODULE;
4190 cdev->ops = &st_fops;
4191 STm->cdevs[rew] = cdev;
4192
4193 error = cdev_add(cdev, cdev_devno, 1);
4194 if (error) {
4195 pr_err("st%d: Can't add %s-rewind mode %d\n", dev_num,
4196 rew ? "non" : "auto", mode);
4197 pr_err("st%d: Device not attached.\n", dev_num);
4198 goto out_free;
4199 }
4200
4201 i = mode << (4 - ST_NBR_MODE_BITS);
4202 snprintf(name, 10, "%s%s%s", rew ? "n" : "",
4203 tape->disk->disk_name, st_formats[i]);
4204
4205 dev = device_create(&st_sysfs_class, &tape->device->sdev_gendev,
4206 cdev_devno, &tape->modes[mode], "%s", name);
4207 if (IS_ERR(dev)) {
4208 pr_err("st%d: device_create failed\n", dev_num);
4209 error = PTR_ERR(dev);
4210 goto out_free;
4211 }
4212
4213 STm->devs[rew] = dev;
4214
4215 return 0;
4216 out_free:
4217 cdev_del(STm->cdevs[rew]);
4218 out:
4219 STm->cdevs[rew] = NULL;
4220 STm->devs[rew] = NULL;
4221 return error;
4222 }
4223
create_cdevs(struct scsi_tape * tape)4224 static int create_cdevs(struct scsi_tape *tape)
4225 {
4226 int mode, error;
4227 for (mode = 0; mode < ST_NBR_MODES; ++mode) {
4228 error = create_one_cdev(tape, mode, 0);
4229 if (error)
4230 return error;
4231 error = create_one_cdev(tape, mode, 1);
4232 if (error)
4233 return error;
4234 }
4235
4236 return sysfs_create_link(&tape->device->sdev_gendev.kobj,
4237 &tape->modes[0].devs[0]->kobj, "tape");
4238 }
4239
remove_cdevs(struct scsi_tape * tape)4240 static void remove_cdevs(struct scsi_tape *tape)
4241 {
4242 int mode, rew;
4243 sysfs_remove_link(&tape->device->sdev_gendev.kobj, "tape");
4244 for (mode = 0; mode < ST_NBR_MODES; mode++) {
4245 struct st_modedef *STm = &(tape->modes[mode]);
4246 for (rew = 0; rew < 2; rew++) {
4247 if (STm->cdevs[rew])
4248 cdev_del(STm->cdevs[rew]);
4249 if (STm->devs[rew])
4250 device_unregister(STm->devs[rew]);
4251 }
4252 }
4253 }
4254
st_probe(struct device * dev)4255 static int st_probe(struct device *dev)
4256 {
4257 struct scsi_device *SDp = to_scsi_device(dev);
4258 struct gendisk *disk = NULL;
4259 struct scsi_tape *tpnt = NULL;
4260 struct st_modedef *STm;
4261 struct st_partstat *STps;
4262 struct st_buffer *buffer;
4263 int i, error;
4264 char *stp;
4265
4266 if (SDp->type != TYPE_TAPE)
4267 return -ENODEV;
4268 if ((stp = st_incompatible(SDp))) {
4269 sdev_printk(KERN_INFO, SDp,
4270 "OnStream tapes are no longer supported;\n");
4271 sdev_printk(KERN_INFO, SDp,
4272 "please mail to linux-scsi@vger.kernel.org.\n");
4273 return -ENODEV;
4274 }
4275
4276 scsi_autopm_get_device(SDp);
4277 i = queue_max_segments(SDp->request_queue);
4278 if (st_max_sg_segs < i)
4279 i = st_max_sg_segs;
4280 buffer = new_tape_buffer((SDp->host)->unchecked_isa_dma, i);
4281 if (buffer == NULL) {
4282 sdev_printk(KERN_ERR, SDp,
4283 "st: Can't allocate new tape buffer. "
4284 "Device not attached.\n");
4285 goto out;
4286 }
4287
4288 disk = alloc_disk(1);
4289 if (!disk) {
4290 sdev_printk(KERN_ERR, SDp,
4291 "st: out of memory. Device not attached.\n");
4292 goto out_buffer_free;
4293 }
4294
4295 tpnt = kzalloc(sizeof(struct scsi_tape), GFP_KERNEL);
4296 if (tpnt == NULL) {
4297 sdev_printk(KERN_ERR, SDp,
4298 "st: Can't allocate device descriptor.\n");
4299 goto out_put_disk;
4300 }
4301 kref_init(&tpnt->kref);
4302 tpnt->disk = disk;
4303 disk->private_data = &tpnt->driver;
4304 /* SCSI tape doesn't register this gendisk via add_disk(). Manually
4305 * take queue reference that release_disk() expects. */
4306 if (!blk_get_queue(SDp->request_queue))
4307 goto out_put_disk;
4308 disk->queue = SDp->request_queue;
4309 tpnt->driver = &st_template;
4310
4311 tpnt->device = SDp;
4312 if (SDp->scsi_level <= 2)
4313 tpnt->tape_type = MT_ISSCSI1;
4314 else
4315 tpnt->tape_type = MT_ISSCSI2;
4316
4317 tpnt->buffer = buffer;
4318 tpnt->buffer->last_SRpnt = NULL;
4319
4320 tpnt->inited = 0;
4321 tpnt->dirty = 0;
4322 tpnt->in_use = 0;
4323 tpnt->drv_buffer = 1; /* Try buffering if no mode sense */
4324 tpnt->restr_dma = (SDp->host)->unchecked_isa_dma;
4325 tpnt->use_pf = (SDp->scsi_level >= SCSI_2);
4326 tpnt->density = 0;
4327 tpnt->do_auto_lock = ST_AUTO_LOCK;
4328 tpnt->can_bsr = (SDp->scsi_level > 2 ? 1 : ST_IN_FILE_POS); /* BSR mandatory in SCSI3 */
4329 tpnt->can_partitions = 0;
4330 tpnt->two_fm = ST_TWO_FM;
4331 tpnt->fast_mteom = ST_FAST_MTEOM;
4332 tpnt->scsi2_logical = ST_SCSI2LOGICAL;
4333 tpnt->sili = ST_SILI;
4334 tpnt->immediate = ST_NOWAIT;
4335 tpnt->immediate_filemark = 0;
4336 tpnt->default_drvbuffer = 0xff; /* No forced buffering */
4337 tpnt->partition = 0;
4338 tpnt->new_partition = 0;
4339 tpnt->nbr_partitions = 0;
4340 blk_queue_rq_timeout(tpnt->device->request_queue, ST_TIMEOUT);
4341 tpnt->long_timeout = ST_LONG_TIMEOUT;
4342 tpnt->try_dio = try_direct_io && !SDp->host->unchecked_isa_dma;
4343
4344 for (i = 0; i < ST_NBR_MODES; i++) {
4345 STm = &(tpnt->modes[i]);
4346 STm->defined = 0;
4347 STm->sysv = ST_SYSV;
4348 STm->defaults_for_writes = 0;
4349 STm->do_async_writes = ST_ASYNC_WRITES;
4350 STm->do_buffer_writes = ST_BUFFER_WRITES;
4351 STm->do_read_ahead = ST_READ_AHEAD;
4352 STm->default_compression = ST_DONT_TOUCH;
4353 STm->default_blksize = (-1); /* No forced size */
4354 STm->default_density = (-1); /* No forced density */
4355 STm->tape = tpnt;
4356 }
4357
4358 for (i = 0; i < ST_NBR_PARTITIONS; i++) {
4359 STps = &(tpnt->ps[i]);
4360 STps->rw = ST_IDLE;
4361 STps->eof = ST_NOEOF;
4362 STps->at_sm = 0;
4363 STps->last_block_valid = 0;
4364 STps->drv_block = (-1);
4365 STps->drv_file = (-1);
4366 }
4367
4368 tpnt->current_mode = 0;
4369 tpnt->modes[0].defined = 1;
4370
4371 tpnt->density_changed = tpnt->compression_changed =
4372 tpnt->blksize_changed = 0;
4373 mutex_init(&tpnt->lock);
4374
4375 idr_preload(GFP_KERNEL);
4376 spin_lock(&st_index_lock);
4377 error = idr_alloc(&st_index_idr, tpnt, 0, ST_MAX_TAPES + 1, GFP_NOWAIT);
4378 spin_unlock(&st_index_lock);
4379 idr_preload_end();
4380 if (error < 0) {
4381 pr_warn("st: idr allocation failed: %d\n", error);
4382 goto out_put_queue;
4383 }
4384 tpnt->index = error;
4385 sprintf(disk->disk_name, "st%d", tpnt->index);
4386 tpnt->stats = kzalloc(sizeof(struct scsi_tape_stats), GFP_KERNEL);
4387 if (tpnt->stats == NULL) {
4388 sdev_printk(KERN_ERR, SDp,
4389 "st: Can't allocate statistics.\n");
4390 goto out_idr_remove;
4391 }
4392
4393 dev_set_drvdata(dev, tpnt);
4394
4395
4396 error = create_cdevs(tpnt);
4397 if (error)
4398 goto out_remove_devs;
4399 scsi_autopm_put_device(SDp);
4400
4401 sdev_printk(KERN_NOTICE, SDp,
4402 "Attached scsi tape %s\n", tape_name(tpnt));
4403 sdev_printk(KERN_INFO, SDp, "%s: try direct i/o: %s (alignment %d B)\n",
4404 tape_name(tpnt), tpnt->try_dio ? "yes" : "no",
4405 queue_dma_alignment(SDp->request_queue) + 1);
4406
4407 return 0;
4408
4409 out_remove_devs:
4410 remove_cdevs(tpnt);
4411 kfree(tpnt->stats);
4412 out_idr_remove:
4413 spin_lock(&st_index_lock);
4414 idr_remove(&st_index_idr, tpnt->index);
4415 spin_unlock(&st_index_lock);
4416 out_put_queue:
4417 blk_put_queue(disk->queue);
4418 out_put_disk:
4419 put_disk(disk);
4420 kfree(tpnt);
4421 out_buffer_free:
4422 kfree(buffer);
4423 out:
4424 scsi_autopm_put_device(SDp);
4425 return -ENODEV;
4426 };
4427
4428
st_remove(struct device * dev)4429 static int st_remove(struct device *dev)
4430 {
4431 struct scsi_tape *tpnt = dev_get_drvdata(dev);
4432 int index = tpnt->index;
4433
4434 scsi_autopm_get_device(to_scsi_device(dev));
4435 remove_cdevs(tpnt);
4436
4437 mutex_lock(&st_ref_mutex);
4438 kref_put(&tpnt->kref, scsi_tape_release);
4439 mutex_unlock(&st_ref_mutex);
4440 spin_lock(&st_index_lock);
4441 idr_remove(&st_index_idr, index);
4442 spin_unlock(&st_index_lock);
4443 return 0;
4444 }
4445
4446 /**
4447 * scsi_tape_release - Called to free the Scsi_Tape structure
4448 * @kref: pointer to embedded kref
4449 *
4450 * st_ref_mutex must be held entering this routine. Because it is
4451 * called on last put, you should always use the scsi_tape_get()
4452 * scsi_tape_put() helpers which manipulate the semaphore directly
4453 * and never do a direct kref_put().
4454 **/
scsi_tape_release(struct kref * kref)4455 static void scsi_tape_release(struct kref *kref)
4456 {
4457 struct scsi_tape *tpnt = to_scsi_tape(kref);
4458 struct gendisk *disk = tpnt->disk;
4459
4460 tpnt->device = NULL;
4461
4462 if (tpnt->buffer) {
4463 normalize_buffer(tpnt->buffer);
4464 kfree(tpnt->buffer->reserved_pages);
4465 kfree(tpnt->buffer);
4466 }
4467
4468 disk->private_data = NULL;
4469 put_disk(disk);
4470 kfree(tpnt->stats);
4471 kfree(tpnt);
4472 return;
4473 }
4474
4475 static struct class st_sysfs_class = {
4476 .name = "scsi_tape",
4477 .dev_groups = st_dev_groups,
4478 };
4479
init_st(void)4480 static int __init init_st(void)
4481 {
4482 int err;
4483
4484 validate_options();
4485
4486 printk(KERN_INFO "st: Version %s, fixed bufsize %d, s/g segs %d\n",
4487 verstr, st_fixed_buffer_size, st_max_sg_segs);
4488
4489 debugging = (debug_flag > 0) ? debug_flag : NO_DEBUG;
4490 if (debugging) {
4491 printk(KERN_INFO "st: Debugging enabled debug_flag = %d\n",
4492 debugging);
4493 }
4494
4495 err = class_register(&st_sysfs_class);
4496 if (err) {
4497 pr_err("Unable register sysfs class for SCSI tapes\n");
4498 return err;
4499 }
4500
4501 err = register_chrdev_region(MKDEV(SCSI_TAPE_MAJOR, 0),
4502 ST_MAX_TAPE_ENTRIES, "st");
4503 if (err) {
4504 printk(KERN_ERR "Unable to get major %d for SCSI tapes\n",
4505 SCSI_TAPE_MAJOR);
4506 goto err_class;
4507 }
4508
4509 err = scsi_register_driver(&st_template.gendrv);
4510 if (err)
4511 goto err_chrdev;
4512
4513 return 0;
4514
4515 err_chrdev:
4516 unregister_chrdev_region(MKDEV(SCSI_TAPE_MAJOR, 0),
4517 ST_MAX_TAPE_ENTRIES);
4518 err_class:
4519 class_unregister(&st_sysfs_class);
4520 return err;
4521 }
4522
exit_st(void)4523 static void __exit exit_st(void)
4524 {
4525 scsi_unregister_driver(&st_template.gendrv);
4526 unregister_chrdev_region(MKDEV(SCSI_TAPE_MAJOR, 0),
4527 ST_MAX_TAPE_ENTRIES);
4528 class_unregister(&st_sysfs_class);
4529 idr_destroy(&st_index_idr);
4530 printk(KERN_INFO "st: Unloaded.\n");
4531 }
4532
4533 module_init(init_st);
4534 module_exit(exit_st);
4535
4536
4537 /* The sysfs driver interface. Read-only at the moment */
try_direct_io_show(struct device_driver * ddp,char * buf)4538 static ssize_t try_direct_io_show(struct device_driver *ddp, char *buf)
4539 {
4540 return scnprintf(buf, PAGE_SIZE, "%d\n", try_direct_io);
4541 }
4542 static DRIVER_ATTR_RO(try_direct_io);
4543
fixed_buffer_size_show(struct device_driver * ddp,char * buf)4544 static ssize_t fixed_buffer_size_show(struct device_driver *ddp, char *buf)
4545 {
4546 return scnprintf(buf, PAGE_SIZE, "%d\n", st_fixed_buffer_size);
4547 }
4548 static DRIVER_ATTR_RO(fixed_buffer_size);
4549
max_sg_segs_show(struct device_driver * ddp,char * buf)4550 static ssize_t max_sg_segs_show(struct device_driver *ddp, char *buf)
4551 {
4552 return scnprintf(buf, PAGE_SIZE, "%d\n", st_max_sg_segs);
4553 }
4554 static DRIVER_ATTR_RO(max_sg_segs);
4555
version_show(struct device_driver * ddd,char * buf)4556 static ssize_t version_show(struct device_driver *ddd, char *buf)
4557 {
4558 return scnprintf(buf, PAGE_SIZE, "[%s]\n", verstr);
4559 }
4560 static DRIVER_ATTR_RO(version);
4561
4562 #if DEBUG
debug_flag_store(struct device_driver * ddp,const char * buf,size_t count)4563 static ssize_t debug_flag_store(struct device_driver *ddp,
4564 const char *buf, size_t count)
4565 {
4566 /* We only care what the first byte of the data is the rest is unused.
4567 * if it's a '1' we turn on debug and if it's a '0' we disable it. All
4568 * other values have -EINVAL returned if they are passed in.
4569 */
4570 if (count > 0) {
4571 if (buf[0] == '0') {
4572 debugging = NO_DEBUG;
4573 return count;
4574 } else if (buf[0] == '1') {
4575 debugging = 1;
4576 return count;
4577 }
4578 }
4579 return -EINVAL;
4580 }
4581
debug_flag_show(struct device_driver * ddp,char * buf)4582 static ssize_t debug_flag_show(struct device_driver *ddp, char *buf)
4583 {
4584 return scnprintf(buf, PAGE_SIZE, "%d\n", debugging);
4585 }
4586 static DRIVER_ATTR_RW(debug_flag);
4587 #endif
4588
4589 static struct attribute *st_drv_attrs[] = {
4590 &driver_attr_try_direct_io.attr,
4591 &driver_attr_fixed_buffer_size.attr,
4592 &driver_attr_max_sg_segs.attr,
4593 &driver_attr_version.attr,
4594 #if DEBUG
4595 &driver_attr_debug_flag.attr,
4596 #endif
4597 NULL,
4598 };
4599 ATTRIBUTE_GROUPS(st_drv);
4600
4601 /* The sysfs simple class interface */
4602 static ssize_t
defined_show(struct device * dev,struct device_attribute * attr,char * buf)4603 defined_show(struct device *dev, struct device_attribute *attr, char *buf)
4604 {
4605 struct st_modedef *STm = dev_get_drvdata(dev);
4606 ssize_t l = 0;
4607
4608 l = snprintf(buf, PAGE_SIZE, "%d\n", STm->defined);
4609 return l;
4610 }
4611 static DEVICE_ATTR_RO(defined);
4612
4613 static ssize_t
default_blksize_show(struct device * dev,struct device_attribute * attr,char * buf)4614 default_blksize_show(struct device *dev, struct device_attribute *attr,
4615 char *buf)
4616 {
4617 struct st_modedef *STm = dev_get_drvdata(dev);
4618 ssize_t l = 0;
4619
4620 l = snprintf(buf, PAGE_SIZE, "%d\n", STm->default_blksize);
4621 return l;
4622 }
4623 static DEVICE_ATTR_RO(default_blksize);
4624
4625 static ssize_t
default_density_show(struct device * dev,struct device_attribute * attr,char * buf)4626 default_density_show(struct device *dev, struct device_attribute *attr,
4627 char *buf)
4628 {
4629 struct st_modedef *STm = dev_get_drvdata(dev);
4630 ssize_t l = 0;
4631 char *fmt;
4632
4633 fmt = STm->default_density >= 0 ? "0x%02x\n" : "%d\n";
4634 l = snprintf(buf, PAGE_SIZE, fmt, STm->default_density);
4635 return l;
4636 }
4637 static DEVICE_ATTR_RO(default_density);
4638
4639 static ssize_t
default_compression_show(struct device * dev,struct device_attribute * attr,char * buf)4640 default_compression_show(struct device *dev, struct device_attribute *attr,
4641 char *buf)
4642 {
4643 struct st_modedef *STm = dev_get_drvdata(dev);
4644 ssize_t l = 0;
4645
4646 l = snprintf(buf, PAGE_SIZE, "%d\n", STm->default_compression - 1);
4647 return l;
4648 }
4649 static DEVICE_ATTR_RO(default_compression);
4650
4651 static ssize_t
options_show(struct device * dev,struct device_attribute * attr,char * buf)4652 options_show(struct device *dev, struct device_attribute *attr, char *buf)
4653 {
4654 struct st_modedef *STm = dev_get_drvdata(dev);
4655 struct scsi_tape *STp = STm->tape;
4656 int options;
4657 ssize_t l = 0;
4658
4659 options = STm->do_buffer_writes ? MT_ST_BUFFER_WRITES : 0;
4660 options |= STm->do_async_writes ? MT_ST_ASYNC_WRITES : 0;
4661 options |= STm->do_read_ahead ? MT_ST_READ_AHEAD : 0;
4662 DEB( options |= debugging ? MT_ST_DEBUGGING : 0 );
4663 options |= STp->two_fm ? MT_ST_TWO_FM : 0;
4664 options |= STp->fast_mteom ? MT_ST_FAST_MTEOM : 0;
4665 options |= STm->defaults_for_writes ? MT_ST_DEF_WRITES : 0;
4666 options |= STp->can_bsr ? MT_ST_CAN_BSR : 0;
4667 options |= STp->omit_blklims ? MT_ST_NO_BLKLIMS : 0;
4668 options |= STp->can_partitions ? MT_ST_CAN_PARTITIONS : 0;
4669 options |= STp->scsi2_logical ? MT_ST_SCSI2LOGICAL : 0;
4670 options |= STm->sysv ? MT_ST_SYSV : 0;
4671 options |= STp->immediate ? MT_ST_NOWAIT : 0;
4672 options |= STp->immediate_filemark ? MT_ST_NOWAIT_EOF : 0;
4673 options |= STp->sili ? MT_ST_SILI : 0;
4674
4675 l = snprintf(buf, PAGE_SIZE, "0x%08x\n", options);
4676 return l;
4677 }
4678 static DEVICE_ATTR_RO(options);
4679
4680 /* Support for tape stats */
4681
4682 /**
4683 * read_cnt_show - return read count - count of reads made from tape drive
4684 * @dev: struct device
4685 * @attr: attribute structure
4686 * @buf: buffer to return formatted data in
4687 */
read_cnt_show(struct device * dev,struct device_attribute * attr,char * buf)4688 static ssize_t read_cnt_show(struct device *dev,
4689 struct device_attribute *attr, char *buf)
4690 {
4691 struct st_modedef *STm = dev_get_drvdata(dev);
4692
4693 return sprintf(buf, "%lld",
4694 (long long)atomic64_read(&STm->tape->stats->read_cnt));
4695 }
4696 static DEVICE_ATTR_RO(read_cnt);
4697
4698 /**
4699 * read_byte_cnt_show - return read byte count - tape drives
4700 * may use blocks less than 512 bytes this gives the raw byte count of
4701 * of data read from the tape drive.
4702 * @dev: struct device
4703 * @attr: attribute structure
4704 * @buf: buffer to return formatted data in
4705 */
read_byte_cnt_show(struct device * dev,struct device_attribute * attr,char * buf)4706 static ssize_t read_byte_cnt_show(struct device *dev,
4707 struct device_attribute *attr, char *buf)
4708 {
4709 struct st_modedef *STm = dev_get_drvdata(dev);
4710
4711 return sprintf(buf, "%lld",
4712 (long long)atomic64_read(&STm->tape->stats->read_byte_cnt));
4713 }
4714 static DEVICE_ATTR_RO(read_byte_cnt);
4715
4716 /**
4717 * read_ns_show - return read ns - overall time spent waiting on reads in ns.
4718 * @dev: struct device
4719 * @attr: attribute structure
4720 * @buf: buffer to return formatted data in
4721 */
read_ns_show(struct device * dev,struct device_attribute * attr,char * buf)4722 static ssize_t read_ns_show(struct device *dev,
4723 struct device_attribute *attr, char *buf)
4724 {
4725 struct st_modedef *STm = dev_get_drvdata(dev);
4726
4727 return sprintf(buf, "%lld",
4728 (long long)atomic64_read(&STm->tape->stats->tot_read_time));
4729 }
4730 static DEVICE_ATTR_RO(read_ns);
4731
4732 /**
4733 * write_cnt_show - write count - number of user calls
4734 * to write(2) that have written data to tape.
4735 * @dev: struct device
4736 * @attr: attribute structure
4737 * @buf: buffer to return formatted data in
4738 */
write_cnt_show(struct device * dev,struct device_attribute * attr,char * buf)4739 static ssize_t write_cnt_show(struct device *dev,
4740 struct device_attribute *attr, char *buf)
4741 {
4742 struct st_modedef *STm = dev_get_drvdata(dev);
4743
4744 return sprintf(buf, "%lld",
4745 (long long)atomic64_read(&STm->tape->stats->write_cnt));
4746 }
4747 static DEVICE_ATTR_RO(write_cnt);
4748
4749 /**
4750 * write_byte_cnt_show - write byte count - raw count of
4751 * bytes written to tape.
4752 * @dev: struct device
4753 * @attr: attribute structure
4754 * @buf: buffer to return formatted data in
4755 */
write_byte_cnt_show(struct device * dev,struct device_attribute * attr,char * buf)4756 static ssize_t write_byte_cnt_show(struct device *dev,
4757 struct device_attribute *attr, char *buf)
4758 {
4759 struct st_modedef *STm = dev_get_drvdata(dev);
4760
4761 return sprintf(buf, "%lld",
4762 (long long)atomic64_read(&STm->tape->stats->write_byte_cnt));
4763 }
4764 static DEVICE_ATTR_RO(write_byte_cnt);
4765
4766 /**
4767 * write_ns_show - write ns - number of nanoseconds waiting on write
4768 * requests to complete.
4769 * @dev: struct device
4770 * @attr: attribute structure
4771 * @buf: buffer to return formatted data in
4772 */
write_ns_show(struct device * dev,struct device_attribute * attr,char * buf)4773 static ssize_t write_ns_show(struct device *dev,
4774 struct device_attribute *attr, char *buf)
4775 {
4776 struct st_modedef *STm = dev_get_drvdata(dev);
4777
4778 return sprintf(buf, "%lld",
4779 (long long)atomic64_read(&STm->tape->stats->tot_write_time));
4780 }
4781 static DEVICE_ATTR_RO(write_ns);
4782
4783 /**
4784 * in_flight_show - number of I/Os currently in flight -
4785 * in most cases this will be either 0 or 1. It may be higher if someone
4786 * has also issued other SCSI commands such as via an ioctl.
4787 * @dev: struct device
4788 * @attr: attribute structure
4789 * @buf: buffer to return formatted data in
4790 */
in_flight_show(struct device * dev,struct device_attribute * attr,char * buf)4791 static ssize_t in_flight_show(struct device *dev,
4792 struct device_attribute *attr, char *buf)
4793 {
4794 struct st_modedef *STm = dev_get_drvdata(dev);
4795
4796 return sprintf(buf, "%lld",
4797 (long long)atomic64_read(&STm->tape->stats->in_flight));
4798 }
4799 static DEVICE_ATTR_RO(in_flight);
4800
4801 /**
4802 * io_ns_show - io wait ns - this is the number of ns spent
4803 * waiting on all I/O to complete. This includes tape movement commands
4804 * such as rewinding, seeking to end of file or tape, it also includes
4805 * read and write. To determine the time spent on tape movement
4806 * subtract the read and write ns from this value.
4807 * @dev: struct device
4808 * @attr: attribute structure
4809 * @buf: buffer to return formatted data in
4810 */
io_ns_show(struct device * dev,struct device_attribute * attr,char * buf)4811 static ssize_t io_ns_show(struct device *dev,
4812 struct device_attribute *attr, char *buf)
4813 {
4814 struct st_modedef *STm = dev_get_drvdata(dev);
4815
4816 return sprintf(buf, "%lld",
4817 (long long)atomic64_read(&STm->tape->stats->tot_io_time));
4818 }
4819 static DEVICE_ATTR_RO(io_ns);
4820
4821 /**
4822 * other_cnt_show - other io count - this is the number of
4823 * I/O requests other than read and write requests.
4824 * Typically these are tape movement requests but will include driver
4825 * tape movement. This includes only requests issued by the st driver.
4826 * @dev: struct device
4827 * @attr: attribute structure
4828 * @buf: buffer to return formatted data in
4829 */
other_cnt_show(struct device * dev,struct device_attribute * attr,char * buf)4830 static ssize_t other_cnt_show(struct device *dev,
4831 struct device_attribute *attr, char *buf)
4832 {
4833 struct st_modedef *STm = dev_get_drvdata(dev);
4834
4835 return sprintf(buf, "%lld",
4836 (long long)atomic64_read(&STm->tape->stats->other_cnt));
4837 }
4838 static DEVICE_ATTR_RO(other_cnt);
4839
4840 /**
4841 * resid_cnt_show - A count of the number of times we get a residual
4842 * count - this should indicate someone issuing reads larger than the
4843 * block size on tape.
4844 * @dev: struct device
4845 * @attr: attribute structure
4846 * @buf: buffer to return formatted data in
4847 */
resid_cnt_show(struct device * dev,struct device_attribute * attr,char * buf)4848 static ssize_t resid_cnt_show(struct device *dev,
4849 struct device_attribute *attr, char *buf)
4850 {
4851 struct st_modedef *STm = dev_get_drvdata(dev);
4852
4853 return sprintf(buf, "%lld",
4854 (long long)atomic64_read(&STm->tape->stats->resid_cnt));
4855 }
4856 static DEVICE_ATTR_RO(resid_cnt);
4857
4858 static struct attribute *st_dev_attrs[] = {
4859 &dev_attr_defined.attr,
4860 &dev_attr_default_blksize.attr,
4861 &dev_attr_default_density.attr,
4862 &dev_attr_default_compression.attr,
4863 &dev_attr_options.attr,
4864 NULL,
4865 };
4866
4867 static struct attribute *st_stats_attrs[] = {
4868 &dev_attr_read_cnt.attr,
4869 &dev_attr_read_byte_cnt.attr,
4870 &dev_attr_read_ns.attr,
4871 &dev_attr_write_cnt.attr,
4872 &dev_attr_write_byte_cnt.attr,
4873 &dev_attr_write_ns.attr,
4874 &dev_attr_in_flight.attr,
4875 &dev_attr_io_ns.attr,
4876 &dev_attr_other_cnt.attr,
4877 &dev_attr_resid_cnt.attr,
4878 NULL,
4879 };
4880
4881 static struct attribute_group stats_group = {
4882 .name = "stats",
4883 .attrs = st_stats_attrs,
4884 };
4885
4886 static struct attribute_group st_group = {
4887 .attrs = st_dev_attrs,
4888 };
4889
4890 static const struct attribute_group *st_dev_groups[] = {
4891 &st_group,
4892 &stats_group,
4893 NULL,
4894 };
4895
4896 /* The following functions may be useful for a larger audience. */
sgl_map_user_pages(struct st_buffer * STbp,const unsigned int max_pages,unsigned long uaddr,size_t count,int rw)4897 static int sgl_map_user_pages(struct st_buffer *STbp,
4898 const unsigned int max_pages, unsigned long uaddr,
4899 size_t count, int rw)
4900 {
4901 unsigned long end = (uaddr + count + PAGE_SIZE - 1) >> PAGE_SHIFT;
4902 unsigned long start = uaddr >> PAGE_SHIFT;
4903 const int nr_pages = end - start;
4904 int res, i, j;
4905 struct page **pages;
4906 struct rq_map_data *mdata = &STbp->map_data;
4907
4908 /* User attempted Overflow! */
4909 if ((uaddr + count) < uaddr)
4910 return -EINVAL;
4911
4912 /* Too big */
4913 if (nr_pages > max_pages)
4914 return -ENOMEM;
4915
4916 /* Hmm? */
4917 if (count == 0)
4918 return 0;
4919
4920 pages = kmalloc_array(max_pages, sizeof(*pages), GFP_KERNEL);
4921 if (pages == NULL)
4922 return -ENOMEM;
4923
4924 /* Try to fault in all of the necessary pages */
4925 /* rw==READ means read from drive, write into memory area */
4926 res = get_user_pages_fast(uaddr, nr_pages, rw == READ ? FOLL_WRITE : 0,
4927 pages);
4928
4929 /* Errors and no page mapped should return here */
4930 if (res < nr_pages)
4931 goto out_unmap;
4932
4933 for (i=0; i < nr_pages; i++) {
4934 /* FIXME: flush superflous for rw==READ,
4935 * probably wrong function for rw==WRITE
4936 */
4937 flush_dcache_page(pages[i]);
4938 }
4939
4940 mdata->offset = uaddr & ~PAGE_MASK;
4941 STbp->mapped_pages = pages;
4942
4943 return nr_pages;
4944 out_unmap:
4945 if (res > 0) {
4946 for (j=0; j < res; j++)
4947 put_page(pages[j]);
4948 res = 0;
4949 }
4950 kfree(pages);
4951 return res;
4952 }
4953
4954
4955 /* And unmap them... */
sgl_unmap_user_pages(struct st_buffer * STbp,const unsigned int nr_pages,int dirtied)4956 static int sgl_unmap_user_pages(struct st_buffer *STbp,
4957 const unsigned int nr_pages, int dirtied)
4958 {
4959 int i;
4960
4961 for (i=0; i < nr_pages; i++) {
4962 struct page *page = STbp->mapped_pages[i];
4963
4964 if (dirtied)
4965 SetPageDirty(page);
4966 /* FIXME: cache flush missing for rw==READ
4967 * FIXME: call the correct reference counting function
4968 */
4969 put_page(page);
4970 }
4971 kfree(STbp->mapped_pages);
4972 STbp->mapped_pages = NULL;
4973
4974 return 0;
4975 }
4976