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.rst 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/compat.h>
26 #include <linux/fs.h>
27 #include <linux/kernel.h>
28 #include <linux/sched/signal.h>
29 #include <linux/mm.h>
30 #include <linux/init.h>
31 #include <linux/string.h>
32 #include <linux/slab.h>
33 #include <linux/errno.h>
34 #include <linux/mtio.h>
35 #include <linux/cdrom.h>
36 #include <linux/ioctl.h>
37 #include <linux/fcntl.h>
38 #include <linux/spinlock.h>
39 #include <linux/blkdev.h>
40 #include <linux/moduleparam.h>
41 #include <linux/cdev.h>
42 #include <linux/idr.h>
43 #include <linux/delay.h>
44 #include <linux/mutex.h>
45
46 #include <linux/uaccess.h>
47 #include <asm/dma.h>
48 #include <asm/unaligned.h>
49
50 #include <scsi/scsi.h>
51 #include <scsi/scsi_dbg.h>
52 #include <scsi/scsi_device.h>
53 #include <scsi/scsi_driver.h>
54 #include <scsi/scsi_eh.h>
55 #include <scsi/scsi_host.h>
56 #include <scsi/scsi_ioctl.h>
57 #include <scsi/sg.h>
58
59
60 /* The driver prints some debugging information on the console if DEBUG
61 is defined and non-zero. */
62 #define DEBUG 1
63 #define NO_DEBUG 0
64
65 #define ST_DEB_MSG KERN_NOTICE
66 #if DEBUG
67 /* The message level for the debug messages is currently set to KERN_NOTICE
68 so that people can easily see the messages. Later when the debugging messages
69 in the drivers are more widely classified, this may be changed to KERN_DEBUG. */
70 #define DEB(a) a
71 #define DEBC(a) if (debugging) { a ; }
72 #else
73 #define DEB(a)
74 #define DEBC(a)
75 #endif
76
77 #define ST_KILOBYTE 1024
78
79 #include "st_options.h"
80 #include "st.h"
81
82 static int buffer_kbs;
83 static int max_sg_segs;
84 static int try_direct_io = TRY_DIRECT_IO;
85 static int try_rdio = 1;
86 static int try_wdio = 1;
87 static int debug_flag;
88
89 static struct class st_sysfs_class;
90 static const struct attribute_group *st_dev_groups[];
91 static const struct attribute_group *st_drv_groups[];
92
93 MODULE_AUTHOR("Kai Makisara");
94 MODULE_DESCRIPTION("SCSI tape (st) driver");
95 MODULE_LICENSE("GPL");
96 MODULE_ALIAS_CHARDEV_MAJOR(SCSI_TAPE_MAJOR);
97 MODULE_ALIAS_SCSI_DEVICE(TYPE_TAPE);
98
99 /* Set 'perm' (4th argument) to 0 to disable module_param's definition
100 * of sysfs parameters (which module_param doesn't yet support).
101 * Sysfs parameters defined explicitly later.
102 */
103 module_param_named(buffer_kbs, buffer_kbs, int, 0);
104 MODULE_PARM_DESC(buffer_kbs, "Default driver buffer size for fixed block mode (KB; 32)");
105 module_param_named(max_sg_segs, max_sg_segs, int, 0);
106 MODULE_PARM_DESC(max_sg_segs, "Maximum number of scatter/gather segments to use (256)");
107 module_param_named(try_direct_io, try_direct_io, int, 0);
108 MODULE_PARM_DESC(try_direct_io, "Try direct I/O between user buffer and tape drive (1)");
109 module_param_named(debug_flag, debug_flag, int, 0);
110 MODULE_PARM_DESC(debug_flag, "Enable DEBUG, same as setting debugging=1");
111
112
113 /* Extra parameters for testing */
114 module_param_named(try_rdio, try_rdio, int, 0);
115 MODULE_PARM_DESC(try_rdio, "Try direct read i/o when possible");
116 module_param_named(try_wdio, try_wdio, int, 0);
117 MODULE_PARM_DESC(try_wdio, "Try direct write i/o when possible");
118
119 #ifndef MODULE
120 static int write_threshold_kbs; /* retained for compatibility */
121 static struct st_dev_parm {
122 char *name;
123 int *val;
124 } parms[] __initdata = {
125 {
126 "buffer_kbs", &buffer_kbs
127 },
128 { /* Retained for compatibility with 2.4 */
129 "write_threshold_kbs", &write_threshold_kbs
130 },
131 {
132 "max_sg_segs", NULL
133 },
134 {
135 "try_direct_io", &try_direct_io
136 },
137 {
138 "debug_flag", &debug_flag
139 }
140 };
141 #endif
142
143 /* Restrict the number of modes so that names for all are assigned */
144 #if ST_NBR_MODES > 16
145 #error "Maximum number of modes is 16"
146 #endif
147 /* Bit reversed order to get same names for same minors with all
148 mode counts */
149 static const char *st_formats[] = {
150 "", "r", "k", "s", "l", "t", "o", "u",
151 "m", "v", "p", "x", "a", "y", "q", "z"};
152
153 /* The default definitions have been moved to st_options.h */
154
155 #define ST_FIXED_BUFFER_SIZE (ST_FIXED_BUFFER_BLOCKS * ST_KILOBYTE)
156
157 /* The buffer size should fit into the 24 bits for length in the
158 6-byte SCSI read and write commands. */
159 #if ST_FIXED_BUFFER_SIZE >= (2 << 24 - 1)
160 #error "Buffer size should not exceed (2 << 24 - 1) bytes!"
161 #endif
162
163 static int debugging = DEBUG;
164
165 #define MAX_RETRIES 0
166 #define MAX_WRITE_RETRIES 0
167 #define MAX_READY_RETRIES 0
168 #define NO_TAPE NOT_READY
169
170 #define ST_TIMEOUT (900 * HZ)
171 #define ST_LONG_TIMEOUT (14000 * HZ)
172
173 /* Remove mode bits and auto-rewind bit (7) */
174 #define TAPE_NR(x) ( ((iminor(x) & ~255) >> (ST_NBR_MODE_BITS + 1)) | \
175 (iminor(x) & ((1 << ST_MODE_SHIFT)-1)))
176 #define TAPE_MODE(x) ((iminor(x) & ST_MODE_MASK) >> ST_MODE_SHIFT)
177
178 /* Construct the minor number from the device (d), mode (m), and non-rewind (n) data */
179 #define TAPE_MINOR(d, m, n) (((d & ~(255 >> (ST_NBR_MODE_BITS + 1))) << (ST_NBR_MODE_BITS + 1)) | \
180 (d & (255 >> (ST_NBR_MODE_BITS + 1))) | (m << ST_MODE_SHIFT) | ((n != 0) << 7) )
181
182 /* Internal ioctl to set both density (uppermost 8 bits) and blocksize (lower
183 24 bits) */
184 #define SET_DENS_AND_BLK 0x10001
185
186 static int st_fixed_buffer_size = ST_FIXED_BUFFER_SIZE;
187 static int st_max_sg_segs = ST_MAX_SG;
188
189 static int modes_defined;
190
191 static int enlarge_buffer(struct st_buffer *, int);
192 static void clear_buffer(struct st_buffer *);
193 static void normalize_buffer(struct st_buffer *);
194 static int append_to_buffer(const char __user *, struct st_buffer *, int);
195 static int from_buffer(struct st_buffer *, char __user *, int);
196 static void move_buffer_data(struct st_buffer *, int);
197
198 static int sgl_map_user_pages(struct st_buffer *, const unsigned int,
199 unsigned long, size_t, int);
200 static int sgl_unmap_user_pages(struct st_buffer *, const unsigned int, int);
201
202 static int st_probe(struct device *);
203 static int st_remove(struct device *);
204
205 static struct scsi_driver st_template = {
206 .gendrv = {
207 .name = "st",
208 .owner = THIS_MODULE,
209 .probe = st_probe,
210 .remove = st_remove,
211 .groups = st_drv_groups,
212 },
213 };
214
215 static int st_compression(struct scsi_tape *, int);
216
217 static int find_partition(struct scsi_tape *);
218 static int switch_partition(struct scsi_tape *);
219
220 static int st_int_ioctl(struct scsi_tape *, unsigned int, unsigned long);
221
222 static void scsi_tape_release(struct kref *);
223
224 #define to_scsi_tape(obj) container_of(obj, struct scsi_tape, kref)
225
226 static DEFINE_MUTEX(st_ref_mutex);
227 static DEFINE_SPINLOCK(st_index_lock);
228 static DEFINE_SPINLOCK(st_use_lock);
229 static DEFINE_IDR(st_index_idr);
230
231
232
233 #ifndef SIGS_FROM_OSST
234 #define SIGS_FROM_OSST \
235 {"OnStream", "SC-", "", "osst"}, \
236 {"OnStream", "DI-", "", "osst"}, \
237 {"OnStream", "DP-", "", "osst"}, \
238 {"OnStream", "USB", "", "osst"}, \
239 {"OnStream", "FW-", "", "osst"}
240 #endif
241
scsi_tape_get(int dev)242 static struct scsi_tape *scsi_tape_get(int dev)
243 {
244 struct scsi_tape *STp = NULL;
245
246 mutex_lock(&st_ref_mutex);
247 spin_lock(&st_index_lock);
248
249 STp = idr_find(&st_index_idr, dev);
250 if (!STp) goto out;
251
252 kref_get(&STp->kref);
253
254 if (!STp->device)
255 goto out_put;
256
257 if (scsi_device_get(STp->device))
258 goto out_put;
259
260 goto out;
261
262 out_put:
263 kref_put(&STp->kref, scsi_tape_release);
264 STp = NULL;
265 out:
266 spin_unlock(&st_index_lock);
267 mutex_unlock(&st_ref_mutex);
268 return STp;
269 }
270
scsi_tape_put(struct scsi_tape * STp)271 static void scsi_tape_put(struct scsi_tape *STp)
272 {
273 struct scsi_device *sdev = STp->device;
274
275 mutex_lock(&st_ref_mutex);
276 kref_put(&STp->kref, scsi_tape_release);
277 scsi_device_put(sdev);
278 mutex_unlock(&st_ref_mutex);
279 }
280
281 struct st_reject_data {
282 char *vendor;
283 char *model;
284 char *rev;
285 char *driver_hint; /* Name of the correct driver, NULL if unknown */
286 };
287
288 static struct st_reject_data reject_list[] = {
289 /* {"XXX", "Yy-", "", NULL}, example */
290 SIGS_FROM_OSST,
291 {NULL, }};
292
293 /* If the device signature is on the list of incompatible drives, the
294 function returns a pointer to the name of the correct driver (if known) */
st_incompatible(struct scsi_device * SDp)295 static char * st_incompatible(struct scsi_device* SDp)
296 {
297 struct st_reject_data *rp;
298
299 for (rp=&(reject_list[0]); rp->vendor != NULL; rp++)
300 if (!strncmp(rp->vendor, SDp->vendor, strlen(rp->vendor)) &&
301 !strncmp(rp->model, SDp->model, strlen(rp->model)) &&
302 !strncmp(rp->rev, SDp->rev, strlen(rp->rev))) {
303 if (rp->driver_hint)
304 return rp->driver_hint;
305 else
306 return "unknown";
307 }
308 return NULL;
309 }
310
311
tape_name(struct scsi_tape * tape)312 static inline char *tape_name(struct scsi_tape *tape)
313 {
314 return tape->disk->disk_name;
315 }
316
317 #define st_printk(prefix, t, fmt, a...) \
318 sdev_prefix_printk(prefix, (t)->device, tape_name(t), fmt, ##a)
319 #ifdef DEBUG
320 #define DEBC_printk(t, fmt, a...) \
321 if (debugging) { st_printk(ST_DEB_MSG, t, fmt, ##a ); }
322 #else
323 #define DEBC_printk(t, fmt, a...)
324 #endif
325
st_analyze_sense(struct st_request * SRpnt,struct st_cmdstatus * s)326 static void st_analyze_sense(struct st_request *SRpnt, struct st_cmdstatus *s)
327 {
328 const u8 *ucp;
329 const u8 *sense = SRpnt->sense;
330
331 s->have_sense = scsi_normalize_sense(SRpnt->sense,
332 SCSI_SENSE_BUFFERSIZE, &s->sense_hdr);
333 s->flags = 0;
334
335 if (s->have_sense) {
336 s->deferred = 0;
337 s->remainder_valid =
338 scsi_get_sense_info_fld(sense, SCSI_SENSE_BUFFERSIZE, &s->uremainder64);
339 switch (sense[0] & 0x7f) {
340 case 0x71:
341 s->deferred = 1;
342 fallthrough;
343 case 0x70:
344 s->fixed_format = 1;
345 s->flags = sense[2] & 0xe0;
346 break;
347 case 0x73:
348 s->deferred = 1;
349 fallthrough;
350 case 0x72:
351 s->fixed_format = 0;
352 ucp = scsi_sense_desc_find(sense, SCSI_SENSE_BUFFERSIZE, 4);
353 s->flags = ucp ? (ucp[3] & 0xe0) : 0;
354 break;
355 }
356 }
357 }
358
359
360 /* Convert the result to success code */
st_chk_result(struct scsi_tape * STp,struct st_request * SRpnt)361 static int st_chk_result(struct scsi_tape *STp, struct st_request * SRpnt)
362 {
363 int result = SRpnt->result;
364 u8 scode;
365 DEB(const char *stp;)
366 char *name = tape_name(STp);
367 struct st_cmdstatus *cmdstatp;
368
369 if (!result)
370 return 0;
371
372 cmdstatp = &STp->buffer->cmdstat;
373 st_analyze_sense(SRpnt, cmdstatp);
374
375 if (cmdstatp->have_sense)
376 scode = STp->buffer->cmdstat.sense_hdr.sense_key;
377 else
378 scode = 0;
379
380 DEB(
381 if (debugging) {
382 st_printk(ST_DEB_MSG, STp,
383 "Error: %x, cmd: %x %x %x %x %x %x\n", result,
384 SRpnt->cmd[0], SRpnt->cmd[1], SRpnt->cmd[2],
385 SRpnt->cmd[3], SRpnt->cmd[4], SRpnt->cmd[5]);
386 if (cmdstatp->have_sense)
387 __scsi_print_sense(STp->device, name,
388 SRpnt->sense, SCSI_SENSE_BUFFERSIZE);
389 } ) /* end DEB */
390 if (!debugging) { /* Abnormal conditions for tape */
391 if (!cmdstatp->have_sense)
392 st_printk(KERN_WARNING, STp,
393 "Error %x (driver bt 0x%x, host bt 0x%x).\n",
394 result, driver_byte(result), host_byte(result));
395 else if (cmdstatp->have_sense &&
396 scode != NO_SENSE &&
397 scode != RECOVERED_ERROR &&
398 /* scode != UNIT_ATTENTION && */
399 scode != BLANK_CHECK &&
400 scode != VOLUME_OVERFLOW &&
401 SRpnt->cmd[0] != MODE_SENSE &&
402 SRpnt->cmd[0] != TEST_UNIT_READY) {
403
404 __scsi_print_sense(STp->device, name,
405 SRpnt->sense, SCSI_SENSE_BUFFERSIZE);
406 }
407 }
408
409 if (cmdstatp->fixed_format &&
410 STp->cln_mode >= EXTENDED_SENSE_START) { /* Only fixed format sense */
411 if (STp->cln_sense_value)
412 STp->cleaning_req |= ((SRpnt->sense[STp->cln_mode] &
413 STp->cln_sense_mask) == STp->cln_sense_value);
414 else
415 STp->cleaning_req |= ((SRpnt->sense[STp->cln_mode] &
416 STp->cln_sense_mask) != 0);
417 }
418 if (cmdstatp->have_sense &&
419 cmdstatp->sense_hdr.asc == 0 && cmdstatp->sense_hdr.ascq == 0x17)
420 STp->cleaning_req = 1; /* ASC and ASCQ => cleaning requested */
421
422 STp->pos_unknown |= STp->device->was_reset;
423
424 if (cmdstatp->have_sense &&
425 scode == RECOVERED_ERROR
426 #if ST_RECOVERED_WRITE_FATAL
427 && SRpnt->cmd[0] != WRITE_6
428 && SRpnt->cmd[0] != WRITE_FILEMARKS
429 #endif
430 ) {
431 STp->recover_count++;
432 STp->recover_reg++;
433
434 DEB(
435 if (debugging) {
436 if (SRpnt->cmd[0] == READ_6)
437 stp = "read";
438 else if (SRpnt->cmd[0] == WRITE_6)
439 stp = "write";
440 else
441 stp = "ioctl";
442 st_printk(ST_DEB_MSG, STp,
443 "Recovered %s error (%d).\n",
444 stp, STp->recover_count);
445 } ) /* end DEB */
446
447 if (cmdstatp->flags == 0)
448 return 0;
449 }
450 return (-EIO);
451 }
452
st_allocate_request(struct scsi_tape * stp)453 static struct st_request *st_allocate_request(struct scsi_tape *stp)
454 {
455 struct st_request *streq;
456
457 streq = kzalloc(sizeof(*streq), GFP_KERNEL);
458 if (streq)
459 streq->stp = stp;
460 else {
461 st_printk(KERN_ERR, stp,
462 "Can't get SCSI request.\n");
463 if (signal_pending(current))
464 stp->buffer->syscall_result = -EINTR;
465 else
466 stp->buffer->syscall_result = -EBUSY;
467 }
468
469 return streq;
470 }
471
st_release_request(struct st_request * streq)472 static void st_release_request(struct st_request *streq)
473 {
474 kfree(streq);
475 }
476
st_do_stats(struct scsi_tape * STp,struct request * req)477 static void st_do_stats(struct scsi_tape *STp, struct request *req)
478 {
479 ktime_t now;
480
481 now = ktime_get();
482 if (scsi_req(req)->cmd[0] == WRITE_6) {
483 now = ktime_sub(now, STp->stats->write_time);
484 atomic64_add(ktime_to_ns(now), &STp->stats->tot_write_time);
485 atomic64_add(ktime_to_ns(now), &STp->stats->tot_io_time);
486 atomic64_inc(&STp->stats->write_cnt);
487 if (scsi_req(req)->result) {
488 atomic64_add(atomic_read(&STp->stats->last_write_size)
489 - STp->buffer->cmdstat.residual,
490 &STp->stats->write_byte_cnt);
491 if (STp->buffer->cmdstat.residual > 0)
492 atomic64_inc(&STp->stats->resid_cnt);
493 } else
494 atomic64_add(atomic_read(&STp->stats->last_write_size),
495 &STp->stats->write_byte_cnt);
496 } else if (scsi_req(req)->cmd[0] == READ_6) {
497 now = ktime_sub(now, STp->stats->read_time);
498 atomic64_add(ktime_to_ns(now), &STp->stats->tot_read_time);
499 atomic64_add(ktime_to_ns(now), &STp->stats->tot_io_time);
500 atomic64_inc(&STp->stats->read_cnt);
501 if (scsi_req(req)->result) {
502 atomic64_add(atomic_read(&STp->stats->last_read_size)
503 - STp->buffer->cmdstat.residual,
504 &STp->stats->read_byte_cnt);
505 if (STp->buffer->cmdstat.residual > 0)
506 atomic64_inc(&STp->stats->resid_cnt);
507 } else
508 atomic64_add(atomic_read(&STp->stats->last_read_size),
509 &STp->stats->read_byte_cnt);
510 } else {
511 now = ktime_sub(now, STp->stats->other_time);
512 atomic64_add(ktime_to_ns(now), &STp->stats->tot_io_time);
513 atomic64_inc(&STp->stats->other_cnt);
514 }
515 atomic64_dec(&STp->stats->in_flight);
516 }
517
st_scsi_execute_end(struct request * req,blk_status_t status)518 static void st_scsi_execute_end(struct request *req, blk_status_t status)
519 {
520 struct st_request *SRpnt = req->end_io_data;
521 struct scsi_request *rq = scsi_req(req);
522 struct scsi_tape *STp = SRpnt->stp;
523 struct bio *tmp;
524
525 STp->buffer->cmdstat.midlevel_result = SRpnt->result = rq->result;
526 STp->buffer->cmdstat.residual = rq->resid_len;
527
528 st_do_stats(STp, req);
529
530 tmp = SRpnt->bio;
531 if (rq->sense_len)
532 memcpy(SRpnt->sense, rq->sense, SCSI_SENSE_BUFFERSIZE);
533 if (SRpnt->waiting)
534 complete(SRpnt->waiting);
535
536 blk_rq_unmap_user(tmp);
537 blk_put_request(req);
538 }
539
st_scsi_execute(struct st_request * SRpnt,const unsigned char * cmd,int data_direction,void * buffer,unsigned bufflen,int timeout,int retries)540 static int st_scsi_execute(struct st_request *SRpnt, const unsigned char *cmd,
541 int data_direction, void *buffer, unsigned bufflen,
542 int timeout, int retries)
543 {
544 struct request *req;
545 struct scsi_request *rq;
546 struct rq_map_data *mdata = &SRpnt->stp->buffer->map_data;
547 int err = 0;
548 struct scsi_tape *STp = SRpnt->stp;
549
550 req = blk_get_request(SRpnt->stp->device->request_queue,
551 data_direction == DMA_TO_DEVICE ?
552 REQ_OP_SCSI_OUT : REQ_OP_SCSI_IN, 0);
553 if (IS_ERR(req))
554 return DRIVER_ERROR << 24;
555 rq = scsi_req(req);
556 req->rq_flags |= RQF_QUIET;
557
558 mdata->null_mapped = 1;
559
560 if (bufflen) {
561 err = blk_rq_map_user(req->q, req, mdata, NULL, bufflen,
562 GFP_KERNEL);
563 if (err) {
564 blk_put_request(req);
565 return DRIVER_ERROR << 24;
566 }
567 }
568
569 atomic64_inc(&STp->stats->in_flight);
570 if (cmd[0] == WRITE_6) {
571 atomic_set(&STp->stats->last_write_size, bufflen);
572 STp->stats->write_time = ktime_get();
573 } else if (cmd[0] == READ_6) {
574 atomic_set(&STp->stats->last_read_size, bufflen);
575 STp->stats->read_time = ktime_get();
576 } else {
577 STp->stats->other_time = ktime_get();
578 }
579
580 SRpnt->bio = req->bio;
581 rq->cmd_len = COMMAND_SIZE(cmd[0]);
582 memset(rq->cmd, 0, BLK_MAX_CDB);
583 memcpy(rq->cmd, cmd, rq->cmd_len);
584 req->timeout = timeout;
585 rq->retries = retries;
586 req->end_io_data = SRpnt;
587
588 blk_execute_rq_nowait(NULL, req, 1, st_scsi_execute_end);
589 return 0;
590 }
591
592 /* Do the scsi command. Waits until command performed if do_wait is true.
593 Otherwise write_behind_check() is used to check that the command
594 has finished. */
595 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)596 st_do_scsi(struct st_request * SRpnt, struct scsi_tape * STp, unsigned char *cmd,
597 int bytes, int direction, int timeout, int retries, int do_wait)
598 {
599 struct completion *waiting;
600 struct rq_map_data *mdata = &STp->buffer->map_data;
601 int ret;
602
603 /* if async, make sure there's no command outstanding */
604 if (!do_wait && ((STp->buffer)->last_SRpnt)) {
605 st_printk(KERN_ERR, STp,
606 "Async command already active.\n");
607 if (signal_pending(current))
608 (STp->buffer)->syscall_result = (-EINTR);
609 else
610 (STp->buffer)->syscall_result = (-EBUSY);
611 return NULL;
612 }
613
614 if (!SRpnt) {
615 SRpnt = st_allocate_request(STp);
616 if (!SRpnt)
617 return NULL;
618 }
619
620 /* If async IO, set last_SRpnt. This ptr tells write_behind_check
621 which IO is outstanding. It's nulled out when the IO completes. */
622 if (!do_wait)
623 (STp->buffer)->last_SRpnt = SRpnt;
624
625 waiting = &STp->wait;
626 init_completion(waiting);
627 SRpnt->waiting = waiting;
628
629 if (STp->buffer->do_dio) {
630 mdata->page_order = 0;
631 mdata->nr_entries = STp->buffer->sg_segs;
632 mdata->pages = STp->buffer->mapped_pages;
633 } else {
634 mdata->page_order = STp->buffer->reserved_page_order;
635 mdata->nr_entries =
636 DIV_ROUND_UP(bytes, PAGE_SIZE << mdata->page_order);
637 mdata->pages = STp->buffer->reserved_pages;
638 mdata->offset = 0;
639 }
640
641 memcpy(SRpnt->cmd, cmd, sizeof(SRpnt->cmd));
642 STp->buffer->cmdstat.have_sense = 0;
643 STp->buffer->syscall_result = 0;
644
645 ret = st_scsi_execute(SRpnt, cmd, direction, NULL, bytes, timeout,
646 retries);
647 if (ret) {
648 /* could not allocate the buffer or request was too large */
649 (STp->buffer)->syscall_result = (-EBUSY);
650 (STp->buffer)->last_SRpnt = NULL;
651 } else if (do_wait) {
652 wait_for_completion(waiting);
653 SRpnt->waiting = NULL;
654 (STp->buffer)->syscall_result = st_chk_result(STp, SRpnt);
655 }
656
657 return SRpnt;
658 }
659
660
661 /* Handle the write-behind checking (waits for completion). Returns -ENOSPC if
662 write has been correct but EOM early warning reached, -EIO if write ended in
663 error or zero if write successful. Asynchronous writes are used only in
664 variable block mode. */
write_behind_check(struct scsi_tape * STp)665 static int write_behind_check(struct scsi_tape * STp)
666 {
667 int retval = 0;
668 struct st_buffer *STbuffer;
669 struct st_partstat *STps;
670 struct st_cmdstatus *cmdstatp;
671 struct st_request *SRpnt;
672
673 STbuffer = STp->buffer;
674 if (!STbuffer->writing)
675 return 0;
676
677 DEB(
678 if (STp->write_pending)
679 STp->nbr_waits++;
680 else
681 STp->nbr_finished++;
682 ) /* end DEB */
683
684 wait_for_completion(&(STp->wait));
685 SRpnt = STbuffer->last_SRpnt;
686 STbuffer->last_SRpnt = NULL;
687 SRpnt->waiting = NULL;
688
689 (STp->buffer)->syscall_result = st_chk_result(STp, SRpnt);
690 st_release_request(SRpnt);
691
692 STbuffer->buffer_bytes -= STbuffer->writing;
693 STps = &(STp->ps[STp->partition]);
694 if (STps->drv_block >= 0) {
695 if (STp->block_size == 0)
696 STps->drv_block++;
697 else
698 STps->drv_block += STbuffer->writing / STp->block_size;
699 }
700
701 cmdstatp = &STbuffer->cmdstat;
702 if (STbuffer->syscall_result) {
703 retval = -EIO;
704 if (cmdstatp->have_sense && !cmdstatp->deferred &&
705 (cmdstatp->flags & SENSE_EOM) &&
706 (cmdstatp->sense_hdr.sense_key == NO_SENSE ||
707 cmdstatp->sense_hdr.sense_key == RECOVERED_ERROR)) {
708 /* EOM at write-behind, has all data been written? */
709 if (!cmdstatp->remainder_valid ||
710 cmdstatp->uremainder64 == 0)
711 retval = -ENOSPC;
712 }
713 if (retval == -EIO)
714 STps->drv_block = -1;
715 }
716 STbuffer->writing = 0;
717
718 DEB(if (debugging && retval)
719 st_printk(ST_DEB_MSG, STp,
720 "Async write error %x, return value %d.\n",
721 STbuffer->cmdstat.midlevel_result, retval);) /* end DEB */
722
723 return retval;
724 }
725
726
727 /* Step over EOF if it has been inadvertently crossed (ioctl not used because
728 it messes up the block number). */
cross_eof(struct scsi_tape * STp,int forward)729 static int cross_eof(struct scsi_tape * STp, int forward)
730 {
731 struct st_request *SRpnt;
732 unsigned char cmd[MAX_COMMAND_SIZE];
733
734 cmd[0] = SPACE;
735 cmd[1] = 0x01; /* Space FileMarks */
736 if (forward) {
737 cmd[2] = cmd[3] = 0;
738 cmd[4] = 1;
739 } else
740 cmd[2] = cmd[3] = cmd[4] = 0xff; /* -1 filemarks */
741 cmd[5] = 0;
742
743 DEBC_printk(STp, "Stepping over filemark %s.\n",
744 forward ? "forward" : "backward");
745
746 SRpnt = st_do_scsi(NULL, STp, cmd, 0, DMA_NONE,
747 STp->device->request_queue->rq_timeout,
748 MAX_RETRIES, 1);
749 if (!SRpnt)
750 return (STp->buffer)->syscall_result;
751
752 st_release_request(SRpnt);
753 SRpnt = NULL;
754
755 if ((STp->buffer)->cmdstat.midlevel_result != 0)
756 st_printk(KERN_ERR, STp,
757 "Stepping over filemark %s failed.\n",
758 forward ? "forward" : "backward");
759
760 return (STp->buffer)->syscall_result;
761 }
762
763
764 /* Flush the write buffer (never need to write if variable blocksize). */
st_flush_write_buffer(struct scsi_tape * STp)765 static int st_flush_write_buffer(struct scsi_tape * STp)
766 {
767 int transfer, blks;
768 int result;
769 unsigned char cmd[MAX_COMMAND_SIZE];
770 struct st_request *SRpnt;
771 struct st_partstat *STps;
772
773 result = write_behind_check(STp);
774 if (result)
775 return result;
776
777 result = 0;
778 if (STp->dirty == 1) {
779
780 transfer = STp->buffer->buffer_bytes;
781 DEBC_printk(STp, "Flushing %d bytes.\n", transfer);
782
783 memset(cmd, 0, MAX_COMMAND_SIZE);
784 cmd[0] = WRITE_6;
785 cmd[1] = 1;
786 blks = transfer / STp->block_size;
787 cmd[2] = blks >> 16;
788 cmd[3] = blks >> 8;
789 cmd[4] = blks;
790
791 SRpnt = st_do_scsi(NULL, STp, cmd, transfer, DMA_TO_DEVICE,
792 STp->device->request_queue->rq_timeout,
793 MAX_WRITE_RETRIES, 1);
794 if (!SRpnt)
795 return (STp->buffer)->syscall_result;
796
797 STps = &(STp->ps[STp->partition]);
798 if ((STp->buffer)->syscall_result != 0) {
799 struct st_cmdstatus *cmdstatp = &STp->buffer->cmdstat;
800
801 if (cmdstatp->have_sense && !cmdstatp->deferred &&
802 (cmdstatp->flags & SENSE_EOM) &&
803 (cmdstatp->sense_hdr.sense_key == NO_SENSE ||
804 cmdstatp->sense_hdr.sense_key == RECOVERED_ERROR) &&
805 (!cmdstatp->remainder_valid ||
806 cmdstatp->uremainder64 == 0)) { /* All written at EOM early warning */
807 STp->dirty = 0;
808 (STp->buffer)->buffer_bytes = 0;
809 if (STps->drv_block >= 0)
810 STps->drv_block += blks;
811 result = (-ENOSPC);
812 } else {
813 st_printk(KERN_ERR, STp, "Error on flush.\n");
814 STps->drv_block = (-1);
815 result = (-EIO);
816 }
817 } else {
818 if (STps->drv_block >= 0)
819 STps->drv_block += blks;
820 STp->dirty = 0;
821 (STp->buffer)->buffer_bytes = 0;
822 }
823 st_release_request(SRpnt);
824 SRpnt = NULL;
825 }
826 return result;
827 }
828
829
830 /* Flush the tape buffer. The tape will be positioned correctly unless
831 seek_next is true. */
flush_buffer(struct scsi_tape * STp,int seek_next)832 static int flush_buffer(struct scsi_tape *STp, int seek_next)
833 {
834 int backspace, result;
835 struct st_partstat *STps;
836
837 /*
838 * If there was a bus reset, block further access
839 * to this device.
840 */
841 if (STp->pos_unknown)
842 return (-EIO);
843
844 if (STp->ready != ST_READY)
845 return 0;
846 STps = &(STp->ps[STp->partition]);
847 if (STps->rw == ST_WRITING) /* Writing */
848 return st_flush_write_buffer(STp);
849
850 if (STp->block_size == 0)
851 return 0;
852
853 backspace = ((STp->buffer)->buffer_bytes +
854 (STp->buffer)->read_pointer) / STp->block_size -
855 ((STp->buffer)->read_pointer + STp->block_size - 1) /
856 STp->block_size;
857 (STp->buffer)->buffer_bytes = 0;
858 (STp->buffer)->read_pointer = 0;
859 result = 0;
860 if (!seek_next) {
861 if (STps->eof == ST_FM_HIT) {
862 result = cross_eof(STp, 0); /* Back over the EOF hit */
863 if (!result)
864 STps->eof = ST_NOEOF;
865 else {
866 if (STps->drv_file >= 0)
867 STps->drv_file++;
868 STps->drv_block = 0;
869 }
870 }
871 if (!result && backspace > 0)
872 result = st_int_ioctl(STp, MTBSR, backspace);
873 } else if (STps->eof == ST_FM_HIT) {
874 if (STps->drv_file >= 0)
875 STps->drv_file++;
876 STps->drv_block = 0;
877 STps->eof = ST_NOEOF;
878 }
879 return result;
880
881 }
882
883 /* Set the mode parameters */
set_mode_densblk(struct scsi_tape * STp,struct st_modedef * STm)884 static int set_mode_densblk(struct scsi_tape * STp, struct st_modedef * STm)
885 {
886 int set_it = 0;
887 unsigned long arg;
888
889 if (!STp->density_changed &&
890 STm->default_density >= 0 &&
891 STm->default_density != STp->density) {
892 arg = STm->default_density;
893 set_it = 1;
894 } else
895 arg = STp->density;
896 arg <<= MT_ST_DENSITY_SHIFT;
897 if (!STp->blksize_changed &&
898 STm->default_blksize >= 0 &&
899 STm->default_blksize != STp->block_size) {
900 arg |= STm->default_blksize;
901 set_it = 1;
902 } else
903 arg |= STp->block_size;
904 if (set_it &&
905 st_int_ioctl(STp, SET_DENS_AND_BLK, arg)) {
906 st_printk(KERN_WARNING, STp,
907 "Can't set default block size to %d bytes "
908 "and density %x.\n",
909 STm->default_blksize, STm->default_density);
910 if (modes_defined)
911 return (-EINVAL);
912 }
913 return 0;
914 }
915
916
917 /* Lock or unlock the drive door. Don't use when st_request allocated. */
do_door_lock(struct scsi_tape * STp,int do_lock)918 static int do_door_lock(struct scsi_tape * STp, int do_lock)
919 {
920 int retval;
921
922 DEBC_printk(STp, "%socking drive door.\n", do_lock ? "L" : "Unl");
923
924 retval = scsi_set_medium_removal(STp->device,
925 do_lock ? SCSI_REMOVAL_PREVENT : SCSI_REMOVAL_ALLOW);
926 if (!retval)
927 STp->door_locked = do_lock ? ST_LOCKED_EXPLICIT : ST_UNLOCKED;
928 else
929 STp->door_locked = ST_LOCK_FAILS;
930 return retval;
931 }
932
933
934 /* Set the internal state after reset */
reset_state(struct scsi_tape * STp)935 static void reset_state(struct scsi_tape *STp)
936 {
937 int i;
938 struct st_partstat *STps;
939
940 STp->pos_unknown = 0;
941 for (i = 0; i < ST_NBR_PARTITIONS; i++) {
942 STps = &(STp->ps[i]);
943 STps->rw = ST_IDLE;
944 STps->eof = ST_NOEOF;
945 STps->at_sm = 0;
946 STps->last_block_valid = 0;
947 STps->drv_block = -1;
948 STps->drv_file = -1;
949 }
950 if (STp->can_partitions) {
951 STp->partition = find_partition(STp);
952 if (STp->partition < 0)
953 STp->partition = 0;
954 STp->new_partition = STp->partition;
955 }
956 }
957
958 /* Test if the drive is ready. Returns either one of the codes below or a negative system
959 error code. */
960 #define CHKRES_READY 0
961 #define CHKRES_NEW_SESSION 1
962 #define CHKRES_NOT_READY 2
963 #define CHKRES_NO_TAPE 3
964
965 #define MAX_ATTENTIONS 10
966
test_ready(struct scsi_tape * STp,int do_wait)967 static int test_ready(struct scsi_tape *STp, int do_wait)
968 {
969 int attentions, waits, max_wait, scode;
970 int retval = CHKRES_READY, new_session = 0;
971 unsigned char cmd[MAX_COMMAND_SIZE];
972 struct st_request *SRpnt = NULL;
973 struct st_cmdstatus *cmdstatp = &STp->buffer->cmdstat;
974
975 max_wait = do_wait ? ST_BLOCK_SECONDS : 0;
976
977 for (attentions=waits=0; ; ) {
978 memset((void *) &cmd[0], 0, MAX_COMMAND_SIZE);
979 cmd[0] = TEST_UNIT_READY;
980 SRpnt = st_do_scsi(SRpnt, STp, cmd, 0, DMA_NONE,
981 STp->long_timeout, MAX_READY_RETRIES, 1);
982
983 if (!SRpnt) {
984 retval = (STp->buffer)->syscall_result;
985 break;
986 }
987
988 if (cmdstatp->have_sense) {
989
990 scode = cmdstatp->sense_hdr.sense_key;
991
992 if (scode == UNIT_ATTENTION) { /* New media? */
993 new_session = 1;
994 if (attentions < MAX_ATTENTIONS) {
995 attentions++;
996 continue;
997 }
998 else {
999 retval = (-EIO);
1000 break;
1001 }
1002 }
1003
1004 if (scode == NOT_READY) {
1005 if (waits < max_wait) {
1006 if (msleep_interruptible(1000)) {
1007 retval = (-EINTR);
1008 break;
1009 }
1010 waits++;
1011 continue;
1012 }
1013 else {
1014 if ((STp->device)->scsi_level >= SCSI_2 &&
1015 cmdstatp->sense_hdr.asc == 0x3a) /* Check ASC */
1016 retval = CHKRES_NO_TAPE;
1017 else
1018 retval = CHKRES_NOT_READY;
1019 break;
1020 }
1021 }
1022 }
1023
1024 retval = (STp->buffer)->syscall_result;
1025 if (!retval)
1026 retval = new_session ? CHKRES_NEW_SESSION : CHKRES_READY;
1027 break;
1028 }
1029
1030 if (SRpnt != NULL)
1031 st_release_request(SRpnt);
1032 return retval;
1033 }
1034
1035
1036 /* See if the drive is ready and gather information about the tape. Return values:
1037 < 0 negative error code from errno.h
1038 0 drive ready
1039 1 drive not ready (possibly no tape)
1040 */
check_tape(struct scsi_tape * STp,struct file * filp)1041 static int check_tape(struct scsi_tape *STp, struct file *filp)
1042 {
1043 int i, retval, new_session = 0, do_wait;
1044 unsigned char cmd[MAX_COMMAND_SIZE], saved_cleaning;
1045 unsigned short st_flags = filp->f_flags;
1046 struct st_request *SRpnt = NULL;
1047 struct st_modedef *STm;
1048 struct st_partstat *STps;
1049 struct inode *inode = file_inode(filp);
1050 int mode = TAPE_MODE(inode);
1051
1052 STp->ready = ST_READY;
1053
1054 if (mode != STp->current_mode) {
1055 DEBC_printk(STp, "Mode change from %d to %d.\n",
1056 STp->current_mode, mode);
1057 new_session = 1;
1058 STp->current_mode = mode;
1059 }
1060 STm = &(STp->modes[STp->current_mode]);
1061
1062 saved_cleaning = STp->cleaning_req;
1063 STp->cleaning_req = 0;
1064
1065 do_wait = ((filp->f_flags & O_NONBLOCK) == 0);
1066 retval = test_ready(STp, do_wait);
1067
1068 if (retval < 0)
1069 goto err_out;
1070
1071 if (retval == CHKRES_NEW_SESSION) {
1072 STp->pos_unknown = 0;
1073 STp->partition = STp->new_partition = 0;
1074 if (STp->can_partitions)
1075 STp->nbr_partitions = 1; /* This guess will be updated later
1076 if necessary */
1077 for (i = 0; i < ST_NBR_PARTITIONS; i++) {
1078 STps = &(STp->ps[i]);
1079 STps->rw = ST_IDLE;
1080 STps->eof = ST_NOEOF;
1081 STps->at_sm = 0;
1082 STps->last_block_valid = 0;
1083 STps->drv_block = 0;
1084 STps->drv_file = 0;
1085 }
1086 new_session = 1;
1087 }
1088 else {
1089 STp->cleaning_req |= saved_cleaning;
1090
1091 if (retval == CHKRES_NOT_READY || retval == CHKRES_NO_TAPE) {
1092 if (retval == CHKRES_NO_TAPE)
1093 STp->ready = ST_NO_TAPE;
1094 else
1095 STp->ready = ST_NOT_READY;
1096
1097 STp->density = 0; /* Clear the erroneous "residue" */
1098 STp->write_prot = 0;
1099 STp->block_size = 0;
1100 STp->ps[0].drv_file = STp->ps[0].drv_block = (-1);
1101 STp->partition = STp->new_partition = 0;
1102 STp->door_locked = ST_UNLOCKED;
1103 return CHKRES_NOT_READY;
1104 }
1105 }
1106
1107 if (STp->omit_blklims)
1108 STp->min_block = STp->max_block = (-1);
1109 else {
1110 memset((void *) &cmd[0], 0, MAX_COMMAND_SIZE);
1111 cmd[0] = READ_BLOCK_LIMITS;
1112
1113 SRpnt = st_do_scsi(SRpnt, STp, cmd, 6, DMA_FROM_DEVICE,
1114 STp->device->request_queue->rq_timeout,
1115 MAX_READY_RETRIES, 1);
1116 if (!SRpnt) {
1117 retval = (STp->buffer)->syscall_result;
1118 goto err_out;
1119 }
1120
1121 if (!SRpnt->result && !STp->buffer->cmdstat.have_sense) {
1122 STp->max_block = ((STp->buffer)->b_data[1] << 16) |
1123 ((STp->buffer)->b_data[2] << 8) | (STp->buffer)->b_data[3];
1124 STp->min_block = ((STp->buffer)->b_data[4] << 8) |
1125 (STp->buffer)->b_data[5];
1126 if ( DEB( debugging || ) !STp->inited)
1127 st_printk(KERN_INFO, STp,
1128 "Block limits %d - %d bytes.\n",
1129 STp->min_block, STp->max_block);
1130 } else {
1131 STp->min_block = STp->max_block = (-1);
1132 DEBC_printk(STp, "Can't read block limits.\n");
1133 }
1134 }
1135
1136 memset((void *) &cmd[0], 0, MAX_COMMAND_SIZE);
1137 cmd[0] = MODE_SENSE;
1138 cmd[4] = 12;
1139
1140 SRpnt = st_do_scsi(SRpnt, STp, cmd, 12, DMA_FROM_DEVICE,
1141 STp->device->request_queue->rq_timeout,
1142 MAX_READY_RETRIES, 1);
1143 if (!SRpnt) {
1144 retval = (STp->buffer)->syscall_result;
1145 goto err_out;
1146 }
1147
1148 if ((STp->buffer)->syscall_result != 0) {
1149 DEBC_printk(STp, "No Mode Sense.\n");
1150 STp->block_size = ST_DEFAULT_BLOCK; /* Educated guess (?) */
1151 (STp->buffer)->syscall_result = 0; /* Prevent error propagation */
1152 STp->drv_write_prot = 0;
1153 } else {
1154 DEBC_printk(STp,"Mode sense. Length %d, "
1155 "medium %x, WBS %x, BLL %d\n",
1156 (STp->buffer)->b_data[0],
1157 (STp->buffer)->b_data[1],
1158 (STp->buffer)->b_data[2],
1159 (STp->buffer)->b_data[3]);
1160
1161 if ((STp->buffer)->b_data[3] >= 8) {
1162 STp->drv_buffer = ((STp->buffer)->b_data[2] >> 4) & 7;
1163 STp->density = (STp->buffer)->b_data[4];
1164 STp->block_size = (STp->buffer)->b_data[9] * 65536 +
1165 (STp->buffer)->b_data[10] * 256 + (STp->buffer)->b_data[11];
1166 DEBC_printk(STp, "Density %x, tape length: %x, "
1167 "drv buffer: %d\n",
1168 STp->density,
1169 (STp->buffer)->b_data[5] * 65536 +
1170 (STp->buffer)->b_data[6] * 256 +
1171 (STp->buffer)->b_data[7],
1172 STp->drv_buffer);
1173 }
1174 STp->drv_write_prot = ((STp->buffer)->b_data[2] & 0x80) != 0;
1175 if (!STp->drv_buffer && STp->immediate_filemark) {
1176 st_printk(KERN_WARNING, STp,
1177 "non-buffered tape: disabling "
1178 "writing immediate filemarks\n");
1179 STp->immediate_filemark = 0;
1180 }
1181 }
1182 st_release_request(SRpnt);
1183 SRpnt = NULL;
1184 STp->inited = 1;
1185
1186 if (STp->block_size > 0)
1187 (STp->buffer)->buffer_blocks =
1188 (STp->buffer)->buffer_size / STp->block_size;
1189 else
1190 (STp->buffer)->buffer_blocks = 1;
1191 (STp->buffer)->buffer_bytes = (STp->buffer)->read_pointer = 0;
1192
1193 DEBC_printk(STp, "Block size: %d, buffer size: %d (%d blocks).\n",
1194 STp->block_size, (STp->buffer)->buffer_size,
1195 (STp->buffer)->buffer_blocks);
1196
1197 if (STp->drv_write_prot) {
1198 STp->write_prot = 1;
1199
1200 DEBC_printk(STp, "Write protected\n");
1201
1202 if (do_wait &&
1203 ((st_flags & O_ACCMODE) == O_WRONLY ||
1204 (st_flags & O_ACCMODE) == O_RDWR)) {
1205 retval = (-EROFS);
1206 goto err_out;
1207 }
1208 }
1209
1210 if (STp->can_partitions && STp->nbr_partitions < 1) {
1211 /* This code is reached when the device is opened for the first time
1212 after the driver has been initialized with tape in the drive and the
1213 partition support has been enabled. */
1214 DEBC_printk(STp, "Updating partition number in status.\n");
1215 if ((STp->partition = find_partition(STp)) < 0) {
1216 retval = STp->partition;
1217 goto err_out;
1218 }
1219 STp->new_partition = STp->partition;
1220 STp->nbr_partitions = 1; /* This guess will be updated when necessary */
1221 }
1222
1223 if (new_session) { /* Change the drive parameters for the new mode */
1224 STp->density_changed = STp->blksize_changed = 0;
1225 STp->compression_changed = 0;
1226 if (!(STm->defaults_for_writes) &&
1227 (retval = set_mode_densblk(STp, STm)) < 0)
1228 goto err_out;
1229
1230 if (STp->default_drvbuffer != 0xff) {
1231 if (st_int_ioctl(STp, MTSETDRVBUFFER, STp->default_drvbuffer))
1232 st_printk(KERN_WARNING, STp,
1233 "Can't set default drive "
1234 "buffering to %d.\n",
1235 STp->default_drvbuffer);
1236 }
1237 }
1238
1239 return CHKRES_READY;
1240
1241 err_out:
1242 return retval;
1243 }
1244
1245
1246 /* Open the device. Needs to take the BKL only because of incrementing the SCSI host
1247 module count. */
st_open(struct inode * inode,struct file * filp)1248 static int st_open(struct inode *inode, struct file *filp)
1249 {
1250 int i, retval = (-EIO);
1251 int resumed = 0;
1252 struct scsi_tape *STp;
1253 struct st_partstat *STps;
1254 int dev = TAPE_NR(inode);
1255
1256 /*
1257 * We really want to do nonseekable_open(inode, filp); here, but some
1258 * versions of tar incorrectly call lseek on tapes and bail out if that
1259 * fails. So we disallow pread() and pwrite(), but permit lseeks.
1260 */
1261 filp->f_mode &= ~(FMODE_PREAD | FMODE_PWRITE);
1262
1263 if (!(STp = scsi_tape_get(dev))) {
1264 return -ENXIO;
1265 }
1266
1267 filp->private_data = STp;
1268
1269 spin_lock(&st_use_lock);
1270 if (STp->in_use) {
1271 spin_unlock(&st_use_lock);
1272 DEBC_printk(STp, "Device already in use.\n");
1273 scsi_tape_put(STp);
1274 return (-EBUSY);
1275 }
1276
1277 STp->in_use = 1;
1278 spin_unlock(&st_use_lock);
1279 STp->rew_at_close = STp->autorew_dev = (iminor(inode) & 0x80) == 0;
1280
1281 if (scsi_autopm_get_device(STp->device) < 0) {
1282 retval = -EIO;
1283 goto err_out;
1284 }
1285 resumed = 1;
1286 if (!scsi_block_when_processing_errors(STp->device)) {
1287 retval = (-ENXIO);
1288 goto err_out;
1289 }
1290
1291 /* See that we have at least a one page buffer available */
1292 if (!enlarge_buffer(STp->buffer, PAGE_SIZE)) {
1293 st_printk(KERN_WARNING, STp,
1294 "Can't allocate one page tape buffer.\n");
1295 retval = (-EOVERFLOW);
1296 goto err_out;
1297 }
1298
1299 (STp->buffer)->cleared = 0;
1300 (STp->buffer)->writing = 0;
1301 (STp->buffer)->syscall_result = 0;
1302
1303 STp->write_prot = ((filp->f_flags & O_ACCMODE) == O_RDONLY);
1304
1305 STp->dirty = 0;
1306 for (i = 0; i < ST_NBR_PARTITIONS; i++) {
1307 STps = &(STp->ps[i]);
1308 STps->rw = ST_IDLE;
1309 }
1310 STp->try_dio_now = STp->try_dio;
1311 STp->recover_count = 0;
1312 DEB( STp->nbr_waits = STp->nbr_finished = 0;
1313 STp->nbr_requests = STp->nbr_dio = STp->nbr_pages = 0; )
1314
1315 retval = check_tape(STp, filp);
1316 if (retval < 0)
1317 goto err_out;
1318 if ((filp->f_flags & O_NONBLOCK) == 0 &&
1319 retval != CHKRES_READY) {
1320 if (STp->ready == NO_TAPE)
1321 retval = (-ENOMEDIUM);
1322 else
1323 retval = (-EIO);
1324 goto err_out;
1325 }
1326 return 0;
1327
1328 err_out:
1329 normalize_buffer(STp->buffer);
1330 spin_lock(&st_use_lock);
1331 STp->in_use = 0;
1332 spin_unlock(&st_use_lock);
1333 if (resumed)
1334 scsi_autopm_put_device(STp->device);
1335 scsi_tape_put(STp);
1336 return retval;
1337
1338 }
1339
1340
1341 /* Flush the tape buffer before close */
st_flush(struct file * filp,fl_owner_t id)1342 static int st_flush(struct file *filp, fl_owner_t id)
1343 {
1344 int result = 0, result2;
1345 unsigned char cmd[MAX_COMMAND_SIZE];
1346 struct st_request *SRpnt;
1347 struct scsi_tape *STp = filp->private_data;
1348 struct st_modedef *STm = &(STp->modes[STp->current_mode]);
1349 struct st_partstat *STps = &(STp->ps[STp->partition]);
1350
1351 if (file_count(filp) > 1)
1352 return 0;
1353
1354 if (STps->rw == ST_WRITING && !STp->pos_unknown) {
1355 result = st_flush_write_buffer(STp);
1356 if (result != 0 && result != (-ENOSPC))
1357 goto out;
1358 }
1359
1360 if (STp->can_partitions &&
1361 (result2 = switch_partition(STp)) < 0) {
1362 DEBC_printk(STp, "switch_partition at close failed.\n");
1363 if (result == 0)
1364 result = result2;
1365 goto out;
1366 }
1367
1368 DEBC( if (STp->nbr_requests)
1369 st_printk(KERN_DEBUG, STp,
1370 "Number of r/w requests %d, dio used in %d, "
1371 "pages %d.\n", STp->nbr_requests, STp->nbr_dio,
1372 STp->nbr_pages));
1373
1374 if (STps->rw == ST_WRITING && !STp->pos_unknown) {
1375 struct st_cmdstatus *cmdstatp = &STp->buffer->cmdstat;
1376
1377 #if DEBUG
1378 DEBC_printk(STp, "Async write waits %d, finished %d.\n",
1379 STp->nbr_waits, STp->nbr_finished);
1380 #endif
1381 memset(cmd, 0, MAX_COMMAND_SIZE);
1382 cmd[0] = WRITE_FILEMARKS;
1383 if (STp->immediate_filemark)
1384 cmd[1] = 1;
1385 cmd[4] = 1 + STp->two_fm;
1386
1387 SRpnt = st_do_scsi(NULL, STp, cmd, 0, DMA_NONE,
1388 STp->device->request_queue->rq_timeout,
1389 MAX_WRITE_RETRIES, 1);
1390 if (!SRpnt) {
1391 result = (STp->buffer)->syscall_result;
1392 goto out;
1393 }
1394
1395 if (STp->buffer->syscall_result == 0 ||
1396 (cmdstatp->have_sense && !cmdstatp->deferred &&
1397 (cmdstatp->flags & SENSE_EOM) &&
1398 (cmdstatp->sense_hdr.sense_key == NO_SENSE ||
1399 cmdstatp->sense_hdr.sense_key == RECOVERED_ERROR) &&
1400 (!cmdstatp->remainder_valid || cmdstatp->uremainder64 == 0))) {
1401 /* Write successful at EOM */
1402 st_release_request(SRpnt);
1403 SRpnt = NULL;
1404 if (STps->drv_file >= 0)
1405 STps->drv_file++;
1406 STps->drv_block = 0;
1407 if (STp->two_fm)
1408 cross_eof(STp, 0);
1409 STps->eof = ST_FM;
1410 }
1411 else { /* Write error */
1412 st_release_request(SRpnt);
1413 SRpnt = NULL;
1414 st_printk(KERN_ERR, STp,
1415 "Error on write filemark.\n");
1416 if (result == 0)
1417 result = (-EIO);
1418 }
1419
1420 DEBC_printk(STp, "Buffer flushed, %d EOF(s) written\n", cmd[4]);
1421 } else if (!STp->rew_at_close) {
1422 STps = &(STp->ps[STp->partition]);
1423 if (!STm->sysv || STps->rw != ST_READING) {
1424 if (STp->can_bsr)
1425 result = flush_buffer(STp, 0);
1426 else if (STps->eof == ST_FM_HIT) {
1427 result = cross_eof(STp, 0);
1428 if (result) {
1429 if (STps->drv_file >= 0)
1430 STps->drv_file++;
1431 STps->drv_block = 0;
1432 STps->eof = ST_FM;
1433 } else
1434 STps->eof = ST_NOEOF;
1435 }
1436 } else if ((STps->eof == ST_NOEOF &&
1437 !(result = cross_eof(STp, 1))) ||
1438 STps->eof == ST_FM_HIT) {
1439 if (STps->drv_file >= 0)
1440 STps->drv_file++;
1441 STps->drv_block = 0;
1442 STps->eof = ST_FM;
1443 }
1444 }
1445
1446 out:
1447 if (STp->rew_at_close) {
1448 result2 = st_int_ioctl(STp, MTREW, 1);
1449 if (result == 0)
1450 result = result2;
1451 }
1452 return result;
1453 }
1454
1455
1456 /* Close the device and release it. BKL is not needed: this is the only thread
1457 accessing this tape. */
st_release(struct inode * inode,struct file * filp)1458 static int st_release(struct inode *inode, struct file *filp)
1459 {
1460 struct scsi_tape *STp = filp->private_data;
1461
1462 if (STp->door_locked == ST_LOCKED_AUTO)
1463 do_door_lock(STp, 0);
1464
1465 normalize_buffer(STp->buffer);
1466 spin_lock(&st_use_lock);
1467 STp->in_use = 0;
1468 spin_unlock(&st_use_lock);
1469 scsi_autopm_put_device(STp->device);
1470 scsi_tape_put(STp);
1471
1472 return 0;
1473 }
1474
1475 /* The checks common to both reading and writing */
rw_checks(struct scsi_tape * STp,struct file * filp,size_t count)1476 static ssize_t rw_checks(struct scsi_tape *STp, struct file *filp, size_t count)
1477 {
1478 ssize_t retval = 0;
1479
1480 /*
1481 * If we are in the middle of error recovery, don't let anyone
1482 * else try and use this device. Also, if error recovery fails, it
1483 * may try and take the device offline, in which case all further
1484 * access to the device is prohibited.
1485 */
1486 if (!scsi_block_when_processing_errors(STp->device)) {
1487 retval = (-ENXIO);
1488 goto out;
1489 }
1490
1491 if (STp->ready != ST_READY) {
1492 if (STp->ready == ST_NO_TAPE)
1493 retval = (-ENOMEDIUM);
1494 else
1495 retval = (-EIO);
1496 goto out;
1497 }
1498
1499 if (! STp->modes[STp->current_mode].defined) {
1500 retval = (-ENXIO);
1501 goto out;
1502 }
1503
1504
1505 /*
1506 * If there was a bus reset, block further access
1507 * to this device.
1508 */
1509 if (STp->pos_unknown) {
1510 retval = (-EIO);
1511 goto out;
1512 }
1513
1514 if (count == 0)
1515 goto out;
1516
1517 DEB(
1518 if (!STp->in_use) {
1519 st_printk(ST_DEB_MSG, STp,
1520 "Incorrect device.\n");
1521 retval = (-EIO);
1522 goto out;
1523 } ) /* end DEB */
1524
1525 if (STp->can_partitions &&
1526 (retval = switch_partition(STp)) < 0)
1527 goto out;
1528
1529 if (STp->block_size == 0 && STp->max_block > 0 &&
1530 (count < STp->min_block || count > STp->max_block)) {
1531 retval = (-EINVAL);
1532 goto out;
1533 }
1534
1535 if (STp->do_auto_lock && STp->door_locked == ST_UNLOCKED &&
1536 !do_door_lock(STp, 1))
1537 STp->door_locked = ST_LOCKED_AUTO;
1538
1539 out:
1540 return retval;
1541 }
1542
1543
setup_buffering(struct scsi_tape * STp,const char __user * buf,size_t count,int is_read)1544 static int setup_buffering(struct scsi_tape *STp, const char __user *buf,
1545 size_t count, int is_read)
1546 {
1547 int i, bufsize, retval = 0;
1548 struct st_buffer *STbp = STp->buffer;
1549
1550 if (is_read)
1551 i = STp->try_dio_now && try_rdio;
1552 else
1553 i = STp->try_dio_now && try_wdio;
1554
1555 if (i && ((unsigned long)buf & queue_dma_alignment(
1556 STp->device->request_queue)) == 0) {
1557 i = sgl_map_user_pages(STbp, STbp->use_sg, (unsigned long)buf,
1558 count, (is_read ? READ : WRITE));
1559 if (i > 0) {
1560 STbp->do_dio = i;
1561 STbp->buffer_bytes = 0; /* can be used as transfer counter */
1562 }
1563 else
1564 STbp->do_dio = 0; /* fall back to buffering with any error */
1565 STbp->sg_segs = STbp->do_dio;
1566 DEB(
1567 if (STbp->do_dio) {
1568 STp->nbr_dio++;
1569 STp->nbr_pages += STbp->do_dio;
1570 }
1571 )
1572 } else
1573 STbp->do_dio = 0;
1574 DEB( STp->nbr_requests++; )
1575
1576 if (!STbp->do_dio) {
1577 if (STp->block_size)
1578 bufsize = STp->block_size > st_fixed_buffer_size ?
1579 STp->block_size : st_fixed_buffer_size;
1580 else {
1581 bufsize = count;
1582 /* Make sure that data from previous user is not leaked even if
1583 HBA does not return correct residual */
1584 if (is_read && STp->sili && !STbp->cleared)
1585 clear_buffer(STbp);
1586 }
1587
1588 if (bufsize > STbp->buffer_size &&
1589 !enlarge_buffer(STbp, bufsize)) {
1590 st_printk(KERN_WARNING, STp,
1591 "Can't allocate %d byte tape buffer.\n",
1592 bufsize);
1593 retval = (-EOVERFLOW);
1594 goto out;
1595 }
1596 if (STp->block_size)
1597 STbp->buffer_blocks = bufsize / STp->block_size;
1598 }
1599
1600 out:
1601 return retval;
1602 }
1603
1604
1605 /* Can be called more than once after each setup_buffer() */
release_buffering(struct scsi_tape * STp,int is_read)1606 static void release_buffering(struct scsi_tape *STp, int is_read)
1607 {
1608 struct st_buffer *STbp;
1609
1610 STbp = STp->buffer;
1611 if (STbp->do_dio) {
1612 sgl_unmap_user_pages(STbp, STbp->do_dio, is_read);
1613 STbp->do_dio = 0;
1614 STbp->sg_segs = 0;
1615 }
1616 }
1617
1618
1619 /* Write command */
1620 static ssize_t
st_write(struct file * filp,const char __user * buf,size_t count,loff_t * ppos)1621 st_write(struct file *filp, const char __user *buf, size_t count, loff_t * ppos)
1622 {
1623 ssize_t total;
1624 ssize_t i, do_count, blks, transfer;
1625 ssize_t retval;
1626 int undone, retry_eot = 0, scode;
1627 int async_write;
1628 unsigned char cmd[MAX_COMMAND_SIZE];
1629 const char __user *b_point;
1630 struct st_request *SRpnt = NULL;
1631 struct scsi_tape *STp = filp->private_data;
1632 struct st_modedef *STm;
1633 struct st_partstat *STps;
1634 struct st_buffer *STbp;
1635
1636 if (mutex_lock_interruptible(&STp->lock))
1637 return -ERESTARTSYS;
1638
1639 retval = rw_checks(STp, filp, count);
1640 if (retval || count == 0)
1641 goto out;
1642
1643 /* Write must be integral number of blocks */
1644 if (STp->block_size != 0 && (count % STp->block_size) != 0) {
1645 st_printk(KERN_WARNING, STp,
1646 "Write not multiple of tape block size.\n");
1647 retval = (-EINVAL);
1648 goto out;
1649 }
1650
1651 STm = &(STp->modes[STp->current_mode]);
1652 STps = &(STp->ps[STp->partition]);
1653
1654 if (STp->write_prot) {
1655 retval = (-EACCES);
1656 goto out;
1657 }
1658
1659
1660 if (STps->rw == ST_READING) {
1661 retval = flush_buffer(STp, 0);
1662 if (retval)
1663 goto out;
1664 STps->rw = ST_WRITING;
1665 } else if (STps->rw != ST_WRITING &&
1666 STps->drv_file == 0 && STps->drv_block == 0) {
1667 if ((retval = set_mode_densblk(STp, STm)) < 0)
1668 goto out;
1669 if (STm->default_compression != ST_DONT_TOUCH &&
1670 !(STp->compression_changed)) {
1671 if (st_compression(STp, (STm->default_compression == ST_YES))) {
1672 st_printk(KERN_WARNING, STp,
1673 "Can't set default compression.\n");
1674 if (modes_defined) {
1675 retval = (-EINVAL);
1676 goto out;
1677 }
1678 }
1679 }
1680 }
1681
1682 STbp = STp->buffer;
1683 i = write_behind_check(STp);
1684 if (i) {
1685 if (i == -ENOSPC)
1686 STps->eof = ST_EOM_OK;
1687 else
1688 STps->eof = ST_EOM_ERROR;
1689 }
1690
1691 if (STps->eof == ST_EOM_OK) {
1692 STps->eof = ST_EOD_1; /* allow next write */
1693 retval = (-ENOSPC);
1694 goto out;
1695 }
1696 else if (STps->eof == ST_EOM_ERROR) {
1697 retval = (-EIO);
1698 goto out;
1699 }
1700
1701 /* Check the buffer readability in cases where copy_user might catch
1702 the problems after some tape movement. */
1703 if (STp->block_size != 0 &&
1704 !STbp->do_dio &&
1705 (copy_from_user(&i, buf, 1) != 0 ||
1706 copy_from_user(&i, buf + count - 1, 1) != 0)) {
1707 retval = (-EFAULT);
1708 goto out;
1709 }
1710
1711 retval = setup_buffering(STp, buf, count, 0);
1712 if (retval)
1713 goto out;
1714
1715 total = count;
1716
1717 memset(cmd, 0, MAX_COMMAND_SIZE);
1718 cmd[0] = WRITE_6;
1719 cmd[1] = (STp->block_size != 0);
1720
1721 STps->rw = ST_WRITING;
1722
1723 b_point = buf;
1724 while (count > 0 && !retry_eot) {
1725
1726 if (STbp->do_dio) {
1727 do_count = count;
1728 }
1729 else {
1730 if (STp->block_size == 0)
1731 do_count = count;
1732 else {
1733 do_count = STbp->buffer_blocks * STp->block_size -
1734 STbp->buffer_bytes;
1735 if (do_count > count)
1736 do_count = count;
1737 }
1738
1739 i = append_to_buffer(b_point, STbp, do_count);
1740 if (i) {
1741 retval = i;
1742 goto out;
1743 }
1744 }
1745 count -= do_count;
1746 b_point += do_count;
1747
1748 async_write = STp->block_size == 0 && !STbp->do_dio &&
1749 STm->do_async_writes && STps->eof < ST_EOM_OK;
1750
1751 if (STp->block_size != 0 && STm->do_buffer_writes &&
1752 !(STp->try_dio_now && try_wdio) && STps->eof < ST_EOM_OK &&
1753 STbp->buffer_bytes < STbp->buffer_size) {
1754 STp->dirty = 1;
1755 /* Don't write a buffer that is not full enough. */
1756 if (!async_write && count == 0)
1757 break;
1758 }
1759
1760 retry_write:
1761 if (STp->block_size == 0)
1762 blks = transfer = do_count;
1763 else {
1764 if (!STbp->do_dio)
1765 blks = STbp->buffer_bytes;
1766 else
1767 blks = do_count;
1768 blks /= STp->block_size;
1769 transfer = blks * STp->block_size;
1770 }
1771 cmd[2] = blks >> 16;
1772 cmd[3] = blks >> 8;
1773 cmd[4] = blks;
1774
1775 SRpnt = st_do_scsi(SRpnt, STp, cmd, transfer, DMA_TO_DEVICE,
1776 STp->device->request_queue->rq_timeout,
1777 MAX_WRITE_RETRIES, !async_write);
1778 if (!SRpnt) {
1779 retval = STbp->syscall_result;
1780 goto out;
1781 }
1782 if (async_write && !STbp->syscall_result) {
1783 STbp->writing = transfer;
1784 STp->dirty = !(STbp->writing ==
1785 STbp->buffer_bytes);
1786 SRpnt = NULL; /* Prevent releasing this request! */
1787 DEB( STp->write_pending = 1; )
1788 break;
1789 }
1790
1791 if (STbp->syscall_result != 0) {
1792 struct st_cmdstatus *cmdstatp = &STp->buffer->cmdstat;
1793
1794 DEBC_printk(STp, "Error on write:\n");
1795 if (cmdstatp->have_sense && (cmdstatp->flags & SENSE_EOM)) {
1796 scode = cmdstatp->sense_hdr.sense_key;
1797 if (cmdstatp->remainder_valid)
1798 undone = (int)cmdstatp->uremainder64;
1799 else if (STp->block_size == 0 &&
1800 scode == VOLUME_OVERFLOW)
1801 undone = transfer;
1802 else
1803 undone = 0;
1804 if (STp->block_size != 0)
1805 undone *= STp->block_size;
1806 if (undone <= do_count) {
1807 /* Only data from this write is not written */
1808 count += undone;
1809 b_point -= undone;
1810 do_count -= undone;
1811 if (STp->block_size)
1812 blks = (transfer - undone) / STp->block_size;
1813 STps->eof = ST_EOM_OK;
1814 /* Continue in fixed block mode if all written
1815 in this request but still something left to write
1816 (retval left to zero)
1817 */
1818 if (STp->block_size == 0 ||
1819 undone > 0 || count == 0)
1820 retval = (-ENOSPC); /* EOM within current request */
1821 DEBC_printk(STp, "EOM with %d "
1822 "bytes unwritten.\n",
1823 (int)count);
1824 } else {
1825 /* EOT within data buffered earlier (possible only
1826 in fixed block mode without direct i/o) */
1827 if (!retry_eot && !cmdstatp->deferred &&
1828 (scode == NO_SENSE || scode == RECOVERED_ERROR)) {
1829 move_buffer_data(STp->buffer, transfer - undone);
1830 retry_eot = 1;
1831 if (STps->drv_block >= 0) {
1832 STps->drv_block += (transfer - undone) /
1833 STp->block_size;
1834 }
1835 STps->eof = ST_EOM_OK;
1836 DEBC_printk(STp, "Retry "
1837 "write of %d "
1838 "bytes at EOM.\n",
1839 STp->buffer->buffer_bytes);
1840 goto retry_write;
1841 }
1842 else {
1843 /* Either error within data buffered by driver or
1844 failed retry */
1845 count -= do_count;
1846 blks = do_count = 0;
1847 STps->eof = ST_EOM_ERROR;
1848 STps->drv_block = (-1); /* Too cautious? */
1849 retval = (-EIO); /* EOM for old data */
1850 DEBC_printk(STp, "EOM with "
1851 "lost data.\n");
1852 }
1853 }
1854 } else {
1855 count += do_count;
1856 STps->drv_block = (-1); /* Too cautious? */
1857 retval = STbp->syscall_result;
1858 }
1859
1860 }
1861
1862 if (STps->drv_block >= 0) {
1863 if (STp->block_size == 0)
1864 STps->drv_block += (do_count > 0);
1865 else
1866 STps->drv_block += blks;
1867 }
1868
1869 STbp->buffer_bytes = 0;
1870 STp->dirty = 0;
1871
1872 if (retval || retry_eot) {
1873 if (count < total)
1874 retval = total - count;
1875 goto out;
1876 }
1877 }
1878
1879 if (STps->eof == ST_EOD_1)
1880 STps->eof = ST_EOM_OK;
1881 else if (STps->eof != ST_EOM_OK)
1882 STps->eof = ST_NOEOF;
1883 retval = total - count;
1884
1885 out:
1886 if (SRpnt != NULL)
1887 st_release_request(SRpnt);
1888 release_buffering(STp, 0);
1889 mutex_unlock(&STp->lock);
1890
1891 return retval;
1892 }
1893
1894 /* Read data from the tape. Returns zero in the normal case, one if the
1895 eof status has changed, and the negative error code in case of a
1896 fatal error. Otherwise updates the buffer and the eof state.
1897
1898 Does release user buffer mapping if it is set.
1899 */
read_tape(struct scsi_tape * STp,long count,struct st_request ** aSRpnt)1900 static long read_tape(struct scsi_tape *STp, long count,
1901 struct st_request ** aSRpnt)
1902 {
1903 int transfer, blks, bytes;
1904 unsigned char cmd[MAX_COMMAND_SIZE];
1905 struct st_request *SRpnt;
1906 struct st_modedef *STm;
1907 struct st_partstat *STps;
1908 struct st_buffer *STbp;
1909 int retval = 0;
1910
1911 if (count == 0)
1912 return 0;
1913
1914 STm = &(STp->modes[STp->current_mode]);
1915 STps = &(STp->ps[STp->partition]);
1916 if (STps->eof == ST_FM_HIT)
1917 return 1;
1918 STbp = STp->buffer;
1919
1920 if (STp->block_size == 0)
1921 blks = bytes = count;
1922 else {
1923 if (!(STp->try_dio_now && try_rdio) && STm->do_read_ahead) {
1924 blks = (STp->buffer)->buffer_blocks;
1925 bytes = blks * STp->block_size;
1926 } else {
1927 bytes = count;
1928 if (!STbp->do_dio && bytes > (STp->buffer)->buffer_size)
1929 bytes = (STp->buffer)->buffer_size;
1930 blks = bytes / STp->block_size;
1931 bytes = blks * STp->block_size;
1932 }
1933 }
1934
1935 memset(cmd, 0, MAX_COMMAND_SIZE);
1936 cmd[0] = READ_6;
1937 cmd[1] = (STp->block_size != 0);
1938 if (!cmd[1] && STp->sili)
1939 cmd[1] |= 2;
1940 cmd[2] = blks >> 16;
1941 cmd[3] = blks >> 8;
1942 cmd[4] = blks;
1943
1944 SRpnt = *aSRpnt;
1945 SRpnt = st_do_scsi(SRpnt, STp, cmd, bytes, DMA_FROM_DEVICE,
1946 STp->device->request_queue->rq_timeout,
1947 MAX_RETRIES, 1);
1948 release_buffering(STp, 1);
1949 *aSRpnt = SRpnt;
1950 if (!SRpnt)
1951 return STbp->syscall_result;
1952
1953 STbp->read_pointer = 0;
1954 STps->at_sm = 0;
1955
1956 /* Something to check */
1957 if (STbp->syscall_result) {
1958 struct st_cmdstatus *cmdstatp = &STp->buffer->cmdstat;
1959
1960 retval = 1;
1961 DEBC_printk(STp,
1962 "Sense: %2x %2x %2x %2x %2x %2x %2x %2x\n",
1963 SRpnt->sense[0], SRpnt->sense[1],
1964 SRpnt->sense[2], SRpnt->sense[3],
1965 SRpnt->sense[4], SRpnt->sense[5],
1966 SRpnt->sense[6], SRpnt->sense[7]);
1967 if (cmdstatp->have_sense) {
1968
1969 if (cmdstatp->sense_hdr.sense_key == BLANK_CHECK)
1970 cmdstatp->flags &= 0xcf; /* No need for EOM in this case */
1971
1972 if (cmdstatp->flags != 0) { /* EOF, EOM, or ILI */
1973 /* Compute the residual count */
1974 if (cmdstatp->remainder_valid)
1975 transfer = (int)cmdstatp->uremainder64;
1976 else
1977 transfer = 0;
1978 if (cmdstatp->sense_hdr.sense_key == MEDIUM_ERROR) {
1979 if (STp->block_size == 0)
1980 transfer = bytes;
1981 /* Some drives set ILI with MEDIUM ERROR */
1982 cmdstatp->flags &= ~SENSE_ILI;
1983 }
1984
1985 if (cmdstatp->flags & SENSE_ILI) { /* ILI */
1986 if (STp->block_size == 0 &&
1987 transfer < 0) {
1988 st_printk(KERN_NOTICE, STp,
1989 "Failed to read %d "
1990 "byte block with %d "
1991 "byte transfer.\n",
1992 bytes - transfer,
1993 bytes);
1994 if (STps->drv_block >= 0)
1995 STps->drv_block += 1;
1996 STbp->buffer_bytes = 0;
1997 return (-ENOMEM);
1998 } else if (STp->block_size == 0) {
1999 STbp->buffer_bytes = bytes - transfer;
2000 } else {
2001 st_release_request(SRpnt);
2002 SRpnt = *aSRpnt = NULL;
2003 if (transfer == blks) { /* We did not get anything, error */
2004 st_printk(KERN_NOTICE, STp,
2005 "Incorrect "
2006 "block size.\n");
2007 if (STps->drv_block >= 0)
2008 STps->drv_block += blks - transfer + 1;
2009 st_int_ioctl(STp, MTBSR, 1);
2010 return (-EIO);
2011 }
2012 /* We have some data, deliver it */
2013 STbp->buffer_bytes = (blks - transfer) *
2014 STp->block_size;
2015 DEBC_printk(STp, "ILI but "
2016 "enough data "
2017 "received %ld "
2018 "%d.\n", count,
2019 STbp->buffer_bytes);
2020 if (STps->drv_block >= 0)
2021 STps->drv_block += 1;
2022 if (st_int_ioctl(STp, MTBSR, 1))
2023 return (-EIO);
2024 }
2025 } else if (cmdstatp->flags & SENSE_FMK) { /* FM overrides EOM */
2026 if (STps->eof != ST_FM_HIT)
2027 STps->eof = ST_FM_HIT;
2028 else
2029 STps->eof = ST_EOD_2;
2030 if (STp->block_size == 0)
2031 STbp->buffer_bytes = 0;
2032 else
2033 STbp->buffer_bytes =
2034 bytes - transfer * STp->block_size;
2035 DEBC_printk(STp, "EOF detected (%d "
2036 "bytes read).\n",
2037 STbp->buffer_bytes);
2038 } else if (cmdstatp->flags & SENSE_EOM) {
2039 if (STps->eof == ST_FM)
2040 STps->eof = ST_EOD_1;
2041 else
2042 STps->eof = ST_EOM_OK;
2043 if (STp->block_size == 0)
2044 STbp->buffer_bytes = bytes - transfer;
2045 else
2046 STbp->buffer_bytes =
2047 bytes - transfer * STp->block_size;
2048
2049 DEBC_printk(STp, "EOM detected (%d "
2050 "bytes read).\n",
2051 STbp->buffer_bytes);
2052 }
2053 }
2054 /* end of EOF, EOM, ILI test */
2055 else { /* nonzero sense key */
2056 DEBC_printk(STp, "Tape error while reading.\n");
2057 STps->drv_block = (-1);
2058 if (STps->eof == ST_FM &&
2059 cmdstatp->sense_hdr.sense_key == BLANK_CHECK) {
2060 DEBC_printk(STp, "Zero returned for "
2061 "first BLANK CHECK "
2062 "after EOF.\n");
2063 STps->eof = ST_EOD_2; /* First BLANK_CHECK after FM */
2064 } else /* Some other extended sense code */
2065 retval = (-EIO);
2066 }
2067
2068 if (STbp->buffer_bytes < 0) /* Caused by bogus sense data */
2069 STbp->buffer_bytes = 0;
2070 }
2071 /* End of extended sense test */
2072 else { /* Non-extended sense */
2073 retval = STbp->syscall_result;
2074 }
2075
2076 }
2077 /* End of error handling */
2078 else { /* Read successful */
2079 STbp->buffer_bytes = bytes;
2080 if (STp->sili) /* In fixed block mode residual is always zero here */
2081 STbp->buffer_bytes -= STp->buffer->cmdstat.residual;
2082 }
2083
2084 if (STps->drv_block >= 0) {
2085 if (STp->block_size == 0)
2086 STps->drv_block++;
2087 else
2088 STps->drv_block += STbp->buffer_bytes / STp->block_size;
2089 }
2090 return retval;
2091 }
2092
2093
2094 /* Read command */
2095 static ssize_t
st_read(struct file * filp,char __user * buf,size_t count,loff_t * ppos)2096 st_read(struct file *filp, char __user *buf, size_t count, loff_t * ppos)
2097 {
2098 ssize_t total;
2099 ssize_t retval = 0;
2100 ssize_t i, transfer;
2101 int special, do_dio = 0;
2102 struct st_request *SRpnt = NULL;
2103 struct scsi_tape *STp = filp->private_data;
2104 struct st_modedef *STm;
2105 struct st_partstat *STps;
2106 struct st_buffer *STbp = STp->buffer;
2107
2108 if (mutex_lock_interruptible(&STp->lock))
2109 return -ERESTARTSYS;
2110
2111 retval = rw_checks(STp, filp, count);
2112 if (retval || count == 0)
2113 goto out;
2114
2115 STm = &(STp->modes[STp->current_mode]);
2116 if (STp->block_size != 0 && (count % STp->block_size) != 0) {
2117 if (!STm->do_read_ahead) {
2118 retval = (-EINVAL); /* Read must be integral number of blocks */
2119 goto out;
2120 }
2121 STp->try_dio_now = 0; /* Direct i/o can't handle split blocks */
2122 }
2123
2124 STps = &(STp->ps[STp->partition]);
2125 if (STps->rw == ST_WRITING) {
2126 retval = flush_buffer(STp, 0);
2127 if (retval)
2128 goto out;
2129 STps->rw = ST_READING;
2130 }
2131 DEB(
2132 if (debugging && STps->eof != ST_NOEOF)
2133 st_printk(ST_DEB_MSG, STp,
2134 "EOF/EOM flag up (%d). Bytes %d\n",
2135 STps->eof, STbp->buffer_bytes);
2136 ) /* end DEB */
2137
2138 retval = setup_buffering(STp, buf, count, 1);
2139 if (retval)
2140 goto out;
2141 do_dio = STbp->do_dio;
2142
2143 if (STbp->buffer_bytes == 0 &&
2144 STps->eof >= ST_EOD_1) {
2145 if (STps->eof < ST_EOD) {
2146 STps->eof += 1;
2147 retval = 0;
2148 goto out;
2149 }
2150 retval = (-EIO); /* EOM or Blank Check */
2151 goto out;
2152 }
2153
2154 if (do_dio) {
2155 /* Check the buffer writability before any tape movement. Don't alter
2156 buffer data. */
2157 if (copy_from_user(&i, buf, 1) != 0 ||
2158 copy_to_user(buf, &i, 1) != 0 ||
2159 copy_from_user(&i, buf + count - 1, 1) != 0 ||
2160 copy_to_user(buf + count - 1, &i, 1) != 0) {
2161 retval = (-EFAULT);
2162 goto out;
2163 }
2164 }
2165
2166 STps->rw = ST_READING;
2167
2168
2169 /* Loop until enough data in buffer or a special condition found */
2170 for (total = 0, special = 0; total < count && !special;) {
2171
2172 /* Get new data if the buffer is empty */
2173 if (STbp->buffer_bytes == 0) {
2174 special = read_tape(STp, count - total, &SRpnt);
2175 if (special < 0) { /* No need to continue read */
2176 retval = special;
2177 goto out;
2178 }
2179 }
2180
2181 /* Move the data from driver buffer to user buffer */
2182 if (STbp->buffer_bytes > 0) {
2183 DEB(
2184 if (debugging && STps->eof != ST_NOEOF)
2185 st_printk(ST_DEB_MSG, STp,
2186 "EOF up (%d). Left %d, needed %d.\n",
2187 STps->eof, STbp->buffer_bytes,
2188 (int)(count - total));
2189 ) /* end DEB */
2190 transfer = STbp->buffer_bytes < count - total ?
2191 STbp->buffer_bytes : count - total;
2192 if (!do_dio) {
2193 i = from_buffer(STbp, buf, transfer);
2194 if (i) {
2195 retval = i;
2196 goto out;
2197 }
2198 }
2199 buf += transfer;
2200 total += transfer;
2201 }
2202
2203 if (STp->block_size == 0)
2204 break; /* Read only one variable length block */
2205
2206 } /* for (total = 0, special = 0;
2207 total < count && !special; ) */
2208
2209 /* Change the eof state if no data from tape or buffer */
2210 if (total == 0) {
2211 if (STps->eof == ST_FM_HIT) {
2212 STps->eof = ST_FM;
2213 STps->drv_block = 0;
2214 if (STps->drv_file >= 0)
2215 STps->drv_file++;
2216 } else if (STps->eof == ST_EOD_1) {
2217 STps->eof = ST_EOD_2;
2218 STps->drv_block = 0;
2219 if (STps->drv_file >= 0)
2220 STps->drv_file++;
2221 } else if (STps->eof == ST_EOD_2)
2222 STps->eof = ST_EOD;
2223 } else if (STps->eof == ST_FM)
2224 STps->eof = ST_NOEOF;
2225 retval = total;
2226
2227 out:
2228 if (SRpnt != NULL) {
2229 st_release_request(SRpnt);
2230 SRpnt = NULL;
2231 }
2232 if (do_dio) {
2233 release_buffering(STp, 1);
2234 STbp->buffer_bytes = 0;
2235 }
2236 mutex_unlock(&STp->lock);
2237
2238 return retval;
2239 }
2240
2241
2242
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); } } )2243 DEB(
2244 /* Set the driver options */
2245 static void st_log_options(struct scsi_tape * STp, struct st_modedef * STm)
2246 {
2247 if (debugging) {
2248 st_printk(KERN_INFO, STp,
2249 "Mode %d options: buffer writes: %d, "
2250 "async writes: %d, read ahead: %d\n",
2251 STp->current_mode, STm->do_buffer_writes,
2252 STm->do_async_writes, STm->do_read_ahead);
2253 st_printk(KERN_INFO, STp,
2254 " can bsr: %d, two FMs: %d, "
2255 "fast mteom: %d, auto lock: %d,\n",
2256 STp->can_bsr, STp->two_fm, STp->fast_mteom,
2257 STp->do_auto_lock);
2258 st_printk(KERN_INFO, STp,
2259 " defs for wr: %d, no block limits: %d, "
2260 "partitions: %d, s2 log: %d\n",
2261 STm->defaults_for_writes, STp->omit_blklims,
2262 STp->can_partitions, STp->scsi2_logical);
2263 st_printk(KERN_INFO, STp,
2264 " sysv: %d nowait: %d sili: %d "
2265 "nowait_filemark: %d\n",
2266 STm->sysv, STp->immediate, STp->sili,
2267 STp->immediate_filemark);
2268 st_printk(KERN_INFO, STp, " debugging: %d\n", debugging);
2269 }
2270 }
2271 )
2272
2273
2274 static int st_set_options(struct scsi_tape *STp, long options)
2275 {
2276 int value;
2277 long code;
2278 struct st_modedef *STm;
2279 struct cdev *cd0, *cd1;
2280 struct device *d0, *d1;
2281
2282 STm = &(STp->modes[STp->current_mode]);
2283 if (!STm->defined) {
2284 cd0 = STm->cdevs[0];
2285 cd1 = STm->cdevs[1];
2286 d0 = STm->devs[0];
2287 d1 = STm->devs[1];
2288 memcpy(STm, &(STp->modes[0]), sizeof(struct st_modedef));
2289 STm->cdevs[0] = cd0;
2290 STm->cdevs[1] = cd1;
2291 STm->devs[0] = d0;
2292 STm->devs[1] = d1;
2293 modes_defined = 1;
2294 DEBC_printk(STp, "Initialized mode %d definition from mode 0\n",
2295 STp->current_mode);
2296 }
2297
2298 code = options & MT_ST_OPTIONS;
2299 if (code == MT_ST_BOOLEANS) {
2300 STm->do_buffer_writes = (options & MT_ST_BUFFER_WRITES) != 0;
2301 STm->do_async_writes = (options & MT_ST_ASYNC_WRITES) != 0;
2302 STm->defaults_for_writes = (options & MT_ST_DEF_WRITES) != 0;
2303 STm->do_read_ahead = (options & MT_ST_READ_AHEAD) != 0;
2304 STp->two_fm = (options & MT_ST_TWO_FM) != 0;
2305 STp->fast_mteom = (options & MT_ST_FAST_MTEOM) != 0;
2306 STp->do_auto_lock = (options & MT_ST_AUTO_LOCK) != 0;
2307 STp->can_bsr = (options & MT_ST_CAN_BSR) != 0;
2308 STp->omit_blklims = (options & MT_ST_NO_BLKLIMS) != 0;
2309 if ((STp->device)->scsi_level >= SCSI_2)
2310 STp->can_partitions = (options & MT_ST_CAN_PARTITIONS) != 0;
2311 STp->scsi2_logical = (options & MT_ST_SCSI2LOGICAL) != 0;
2312 STp->immediate = (options & MT_ST_NOWAIT) != 0;
2313 STp->immediate_filemark = (options & MT_ST_NOWAIT_EOF) != 0;
2314 STm->sysv = (options & MT_ST_SYSV) != 0;
2315 STp->sili = (options & MT_ST_SILI) != 0;
2316 DEB( debugging = (options & MT_ST_DEBUGGING) != 0;
2317 st_log_options(STp, STm); )
2318 } else if (code == MT_ST_SETBOOLEANS || code == MT_ST_CLEARBOOLEANS) {
2319 value = (code == MT_ST_SETBOOLEANS);
2320 if ((options & MT_ST_BUFFER_WRITES) != 0)
2321 STm->do_buffer_writes = value;
2322 if ((options & MT_ST_ASYNC_WRITES) != 0)
2323 STm->do_async_writes = value;
2324 if ((options & MT_ST_DEF_WRITES) != 0)
2325 STm->defaults_for_writes = value;
2326 if ((options & MT_ST_READ_AHEAD) != 0)
2327 STm->do_read_ahead = value;
2328 if ((options & MT_ST_TWO_FM) != 0)
2329 STp->two_fm = value;
2330 if ((options & MT_ST_FAST_MTEOM) != 0)
2331 STp->fast_mteom = value;
2332 if ((options & MT_ST_AUTO_LOCK) != 0)
2333 STp->do_auto_lock = value;
2334 if ((options & MT_ST_CAN_BSR) != 0)
2335 STp->can_bsr = value;
2336 if ((options & MT_ST_NO_BLKLIMS) != 0)
2337 STp->omit_blklims = value;
2338 if ((STp->device)->scsi_level >= SCSI_2 &&
2339 (options & MT_ST_CAN_PARTITIONS) != 0)
2340 STp->can_partitions = value;
2341 if ((options & MT_ST_SCSI2LOGICAL) != 0)
2342 STp->scsi2_logical = value;
2343 if ((options & MT_ST_NOWAIT) != 0)
2344 STp->immediate = value;
2345 if ((options & MT_ST_NOWAIT_EOF) != 0)
2346 STp->immediate_filemark = value;
2347 if ((options & MT_ST_SYSV) != 0)
2348 STm->sysv = value;
2349 if ((options & MT_ST_SILI) != 0)
2350 STp->sili = value;
2351 DEB(
2352 if ((options & MT_ST_DEBUGGING) != 0)
2353 debugging = value;
2354 st_log_options(STp, STm); )
2355 } else if (code == MT_ST_WRITE_THRESHOLD) {
2356 /* Retained for compatibility */
2357 } else if (code == MT_ST_DEF_BLKSIZE) {
2358 value = (options & ~MT_ST_OPTIONS);
2359 if (value == ~MT_ST_OPTIONS) {
2360 STm->default_blksize = (-1);
2361 DEBC_printk(STp, "Default block size disabled.\n");
2362 } else {
2363 STm->default_blksize = value;
2364 DEBC_printk(STp,"Default block size set to "
2365 "%d bytes.\n", STm->default_blksize);
2366 if (STp->ready == ST_READY) {
2367 STp->blksize_changed = 0;
2368 set_mode_densblk(STp, STm);
2369 }
2370 }
2371 } else if (code == MT_ST_TIMEOUTS) {
2372 value = (options & ~MT_ST_OPTIONS);
2373 if ((value & MT_ST_SET_LONG_TIMEOUT) != 0) {
2374 STp->long_timeout = (value & ~MT_ST_SET_LONG_TIMEOUT) * HZ;
2375 DEBC_printk(STp, "Long timeout set to %d seconds.\n",
2376 (value & ~MT_ST_SET_LONG_TIMEOUT));
2377 } else {
2378 blk_queue_rq_timeout(STp->device->request_queue,
2379 value * HZ);
2380 DEBC_printk(STp, "Normal timeout set to %d seconds.\n",
2381 value);
2382 }
2383 } else if (code == MT_ST_SET_CLN) {
2384 value = (options & ~MT_ST_OPTIONS) & 0xff;
2385 if (value != 0 &&
2386 (value < EXTENDED_SENSE_START ||
2387 value >= SCSI_SENSE_BUFFERSIZE))
2388 return (-EINVAL);
2389 STp->cln_mode = value;
2390 STp->cln_sense_mask = (options >> 8) & 0xff;
2391 STp->cln_sense_value = (options >> 16) & 0xff;
2392 st_printk(KERN_INFO, STp,
2393 "Cleaning request mode %d, mask %02x, value %02x\n",
2394 value, STp->cln_sense_mask, STp->cln_sense_value);
2395 } else if (code == MT_ST_DEF_OPTIONS) {
2396 code = (options & ~MT_ST_CLEAR_DEFAULT);
2397 value = (options & MT_ST_CLEAR_DEFAULT);
2398 if (code == MT_ST_DEF_DENSITY) {
2399 if (value == MT_ST_CLEAR_DEFAULT) {
2400 STm->default_density = (-1);
2401 DEBC_printk(STp,
2402 "Density default disabled.\n");
2403 } else {
2404 STm->default_density = value & 0xff;
2405 DEBC_printk(STp, "Density default set to %x\n",
2406 STm->default_density);
2407 if (STp->ready == ST_READY) {
2408 STp->density_changed = 0;
2409 set_mode_densblk(STp, STm);
2410 }
2411 }
2412 } else if (code == MT_ST_DEF_DRVBUFFER) {
2413 if (value == MT_ST_CLEAR_DEFAULT) {
2414 STp->default_drvbuffer = 0xff;
2415 DEBC_printk(STp,
2416 "Drive buffer default disabled.\n");
2417 } else {
2418 STp->default_drvbuffer = value & 7;
2419 DEBC_printk(STp,
2420 "Drive buffer default set to %x\n",
2421 STp->default_drvbuffer);
2422 if (STp->ready == ST_READY)
2423 st_int_ioctl(STp, MTSETDRVBUFFER, STp->default_drvbuffer);
2424 }
2425 } else if (code == MT_ST_DEF_COMPRESSION) {
2426 if (value == MT_ST_CLEAR_DEFAULT) {
2427 STm->default_compression = ST_DONT_TOUCH;
2428 DEBC_printk(STp,
2429 "Compression default disabled.\n");
2430 } else {
2431 if ((value & 0xff00) != 0) {
2432 STp->c_algo = (value & 0xff00) >> 8;
2433 DEBC_printk(STp, "Compression "
2434 "algorithm set to 0x%x.\n",
2435 STp->c_algo);
2436 }
2437 if ((value & 0xff) != 0xff) {
2438 STm->default_compression = (value & 1 ? ST_YES : ST_NO);
2439 DEBC_printk(STp, "Compression default "
2440 "set to %x\n",
2441 (value & 1));
2442 if (STp->ready == ST_READY) {
2443 STp->compression_changed = 0;
2444 st_compression(STp, (STm->default_compression == ST_YES));
2445 }
2446 }
2447 }
2448 }
2449 } else
2450 return (-EIO);
2451
2452 return 0;
2453 }
2454
2455 #define MODE_HEADER_LENGTH 4
2456
2457 /* Mode header and page byte offsets */
2458 #define MH_OFF_DATA_LENGTH 0
2459 #define MH_OFF_MEDIUM_TYPE 1
2460 #define MH_OFF_DEV_SPECIFIC 2
2461 #define MH_OFF_BDESCS_LENGTH 3
2462 #define MP_OFF_PAGE_NBR 0
2463 #define MP_OFF_PAGE_LENGTH 1
2464
2465 /* Mode header and page bit masks */
2466 #define MH_BIT_WP 0x80
2467 #define MP_MSK_PAGE_NBR 0x3f
2468
2469 /* Don't return block descriptors */
2470 #define MODE_SENSE_OMIT_BDESCS 0x08
2471
2472 #define MODE_SELECT_PAGE_FORMAT 0x10
2473
2474 /* Read a mode page into the tape buffer. The block descriptors are included
2475 if incl_block_descs is true. The page control is ored to the page number
2476 parameter, if necessary. */
read_mode_page(struct scsi_tape * STp,int page,int omit_block_descs)2477 static int read_mode_page(struct scsi_tape *STp, int page, int omit_block_descs)
2478 {
2479 unsigned char cmd[MAX_COMMAND_SIZE];
2480 struct st_request *SRpnt;
2481
2482 memset(cmd, 0, MAX_COMMAND_SIZE);
2483 cmd[0] = MODE_SENSE;
2484 if (omit_block_descs)
2485 cmd[1] = MODE_SENSE_OMIT_BDESCS;
2486 cmd[2] = page;
2487 cmd[4] = 255;
2488
2489 SRpnt = st_do_scsi(NULL, STp, cmd, cmd[4], DMA_FROM_DEVICE,
2490 STp->device->request_queue->rq_timeout, 0, 1);
2491 if (SRpnt == NULL)
2492 return (STp->buffer)->syscall_result;
2493
2494 st_release_request(SRpnt);
2495
2496 return STp->buffer->syscall_result;
2497 }
2498
2499
2500 /* Send the mode page in the tape buffer to the drive. Assumes that the mode data
2501 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)2502 static int write_mode_page(struct scsi_tape *STp, int page, int slow)
2503 {
2504 int pgo;
2505 unsigned char cmd[MAX_COMMAND_SIZE];
2506 struct st_request *SRpnt;
2507 int timeout;
2508
2509 memset(cmd, 0, MAX_COMMAND_SIZE);
2510 cmd[0] = MODE_SELECT;
2511 cmd[1] = MODE_SELECT_PAGE_FORMAT;
2512 pgo = MODE_HEADER_LENGTH + (STp->buffer)->b_data[MH_OFF_BDESCS_LENGTH];
2513 cmd[4] = pgo + (STp->buffer)->b_data[pgo + MP_OFF_PAGE_LENGTH] + 2;
2514
2515 /* Clear reserved fields */
2516 (STp->buffer)->b_data[MH_OFF_DATA_LENGTH] = 0;
2517 (STp->buffer)->b_data[MH_OFF_MEDIUM_TYPE] = 0;
2518 (STp->buffer)->b_data[MH_OFF_DEV_SPECIFIC] &= ~MH_BIT_WP;
2519 (STp->buffer)->b_data[pgo + MP_OFF_PAGE_NBR] &= MP_MSK_PAGE_NBR;
2520
2521 timeout = slow ?
2522 STp->long_timeout : STp->device->request_queue->rq_timeout;
2523 SRpnt = st_do_scsi(NULL, STp, cmd, cmd[4], DMA_TO_DEVICE,
2524 timeout, 0, 1);
2525 if (SRpnt == NULL)
2526 return (STp->buffer)->syscall_result;
2527
2528 st_release_request(SRpnt);
2529
2530 return STp->buffer->syscall_result;
2531 }
2532
2533
2534 #define COMPRESSION_PAGE 0x0f
2535 #define COMPRESSION_PAGE_LENGTH 16
2536
2537 #define CP_OFF_DCE_DCC 2
2538 #define CP_OFF_C_ALGO 7
2539
2540 #define DCE_MASK 0x80
2541 #define DCC_MASK 0x40
2542 #define RED_MASK 0x60
2543
2544
2545 /* Control the compression with mode page 15. Algorithm not changed if zero.
2546
2547 The block descriptors are read and written because Sony SDT-7000 does not
2548 work without this (suggestion from Michael Schaefer <Michael.Schaefer@dlr.de>).
2549 Including block descriptors should not cause any harm to other drives. */
2550
st_compression(struct scsi_tape * STp,int state)2551 static int st_compression(struct scsi_tape * STp, int state)
2552 {
2553 int retval;
2554 int mpoffs; /* Offset to mode page start */
2555 unsigned char *b_data = (STp->buffer)->b_data;
2556
2557 if (STp->ready != ST_READY)
2558 return (-EIO);
2559
2560 /* Read the current page contents */
2561 retval = read_mode_page(STp, COMPRESSION_PAGE, 0);
2562 if (retval) {
2563 DEBC_printk(STp, "Compression mode page not supported.\n");
2564 return (-EIO);
2565 }
2566
2567 mpoffs = MODE_HEADER_LENGTH + b_data[MH_OFF_BDESCS_LENGTH];
2568 DEBC_printk(STp, "Compression state is %d.\n",
2569 (b_data[mpoffs + CP_OFF_DCE_DCC] & DCE_MASK ? 1 : 0));
2570
2571 /* Check if compression can be changed */
2572 if ((b_data[mpoffs + CP_OFF_DCE_DCC] & DCC_MASK) == 0) {
2573 DEBC_printk(STp, "Compression not supported.\n");
2574 return (-EIO);
2575 }
2576
2577 /* Do the change */
2578 if (state) {
2579 b_data[mpoffs + CP_OFF_DCE_DCC] |= DCE_MASK;
2580 if (STp->c_algo != 0)
2581 b_data[mpoffs + CP_OFF_C_ALGO] = STp->c_algo;
2582 }
2583 else {
2584 b_data[mpoffs + CP_OFF_DCE_DCC] &= ~DCE_MASK;
2585 if (STp->c_algo != 0)
2586 b_data[mpoffs + CP_OFF_C_ALGO] = 0; /* no compression */
2587 }
2588
2589 retval = write_mode_page(STp, COMPRESSION_PAGE, 0);
2590 if (retval) {
2591 DEBC_printk(STp, "Compression change failed.\n");
2592 return (-EIO);
2593 }
2594 DEBC_printk(STp, "Compression state changed to %d.\n", state);
2595
2596 STp->compression_changed = 1;
2597 return 0;
2598 }
2599
2600
2601 /* 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)2602 static int do_load_unload(struct scsi_tape *STp, struct file *filp, int load_code)
2603 {
2604 int retval = (-EIO), timeout;
2605 unsigned char cmd[MAX_COMMAND_SIZE];
2606 struct st_partstat *STps;
2607 struct st_request *SRpnt;
2608
2609 if (STp->ready != ST_READY && !load_code) {
2610 if (STp->ready == ST_NO_TAPE)
2611 return (-ENOMEDIUM);
2612 else
2613 return (-EIO);
2614 }
2615
2616 memset(cmd, 0, MAX_COMMAND_SIZE);
2617 cmd[0] = START_STOP;
2618 if (load_code)
2619 cmd[4] |= 1;
2620 /*
2621 * If arg >= 1 && arg <= 6 Enhanced load/unload in HP C1553A
2622 */
2623 if (load_code >= 1 + MT_ST_HPLOADER_OFFSET
2624 && load_code <= 6 + MT_ST_HPLOADER_OFFSET) {
2625 DEBC_printk(STp, " Enhanced %sload slot %2d.\n",
2626 (cmd[4]) ? "" : "un",
2627 load_code - MT_ST_HPLOADER_OFFSET);
2628 cmd[3] = load_code - MT_ST_HPLOADER_OFFSET; /* MediaID field of C1553A */
2629 }
2630 if (STp->immediate) {
2631 cmd[1] = 1; /* Don't wait for completion */
2632 timeout = STp->device->request_queue->rq_timeout;
2633 }
2634 else
2635 timeout = STp->long_timeout;
2636
2637 DEBC(
2638 if (!load_code)
2639 st_printk(ST_DEB_MSG, STp, "Unloading tape.\n");
2640 else
2641 st_printk(ST_DEB_MSG, STp, "Loading tape.\n");
2642 );
2643
2644 SRpnt = st_do_scsi(NULL, STp, cmd, 0, DMA_NONE,
2645 timeout, MAX_RETRIES, 1);
2646 if (!SRpnt)
2647 return (STp->buffer)->syscall_result;
2648
2649 retval = (STp->buffer)->syscall_result;
2650 st_release_request(SRpnt);
2651
2652 if (!retval) { /* SCSI command successful */
2653
2654 if (!load_code) {
2655 STp->rew_at_close = 0;
2656 STp->ready = ST_NO_TAPE;
2657 }
2658 else {
2659 STp->rew_at_close = STp->autorew_dev;
2660 retval = check_tape(STp, filp);
2661 if (retval > 0)
2662 retval = 0;
2663 }
2664 }
2665 else {
2666 STps = &(STp->ps[STp->partition]);
2667 STps->drv_file = STps->drv_block = (-1);
2668 }
2669
2670 return retval;
2671 }
2672
2673 #if DEBUG
2674 #define ST_DEB_FORWARD 0
2675 #define ST_DEB_BACKWARD 1
deb_space_print(struct scsi_tape * STp,int direction,char * units,unsigned char * cmd)2676 static void deb_space_print(struct scsi_tape *STp, int direction, char *units, unsigned char *cmd)
2677 {
2678 s32 sc;
2679
2680 if (!debugging)
2681 return;
2682
2683 sc = sign_extend32(get_unaligned_be24(&cmd[2]), 23);
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 fallthrough;
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 fallthrough;
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 case MTRETEN:
2850 cmd[0] = START_STOP;
2851 if (STp->immediate) {
2852 cmd[1] = 1; /* Don't wait for completion */
2853 timeout = STp->device->request_queue->rq_timeout;
2854 }
2855 cmd[4] = 3;
2856 DEBC_printk(STp, "Retensioning tape.\n");
2857 fileno = blkno = at_sm = 0;
2858 break;
2859 case MTEOM:
2860 if (!STp->fast_mteom) {
2861 /* space to the end of tape */
2862 ioctl_result = st_int_ioctl(STp, MTFSF, 0x7fffff);
2863 fileno = STps->drv_file;
2864 if (STps->eof >= ST_EOD_1)
2865 return 0;
2866 /* The next lines would hide the number of spaced FileMarks
2867 That's why I inserted the previous lines. I had no luck
2868 with detecting EOM with FSF, so we go now to EOM.
2869 Joerg Weule */
2870 } else
2871 fileno = (-1);
2872 cmd[0] = SPACE;
2873 cmd[1] = 3;
2874 DEBC_printk(STp, "Spacing to end of recorded medium.\n");
2875 blkno = -1;
2876 at_sm = 0;
2877 break;
2878 case MTERASE:
2879 if (STp->write_prot)
2880 return (-EACCES);
2881 cmd[0] = ERASE;
2882 cmd[1] = (arg ? 1 : 0); /* Long erase with non-zero argument */
2883 if (STp->immediate) {
2884 cmd[1] |= 2; /* Don't wait for completion */
2885 timeout = STp->device->request_queue->rq_timeout;
2886 }
2887 else
2888 timeout = STp->long_timeout * 8;
2889
2890 DEBC_printk(STp, "Erasing tape.\n");
2891 fileno = blkno = at_sm = 0;
2892 break;
2893 case MTSETBLK: /* Set block length */
2894 case MTSETDENSITY: /* Set tape density */
2895 case MTSETDRVBUFFER: /* Set drive buffering */
2896 case SET_DENS_AND_BLK: /* Set density and block size */
2897 chg_eof = 0;
2898 if (STp->dirty || (STp->buffer)->buffer_bytes != 0)
2899 return (-EIO); /* Not allowed if data in buffer */
2900 if ((cmd_in == MTSETBLK || cmd_in == SET_DENS_AND_BLK) &&
2901 (arg & MT_ST_BLKSIZE_MASK) != 0 &&
2902 STp->max_block > 0 &&
2903 ((arg & MT_ST_BLKSIZE_MASK) < STp->min_block ||
2904 (arg & MT_ST_BLKSIZE_MASK) > STp->max_block)) {
2905 st_printk(KERN_WARNING, STp, "Illegal block size.\n");
2906 return (-EINVAL);
2907 }
2908 cmd[0] = MODE_SELECT;
2909 if ((STp->use_pf & USE_PF))
2910 cmd[1] = MODE_SELECT_PAGE_FORMAT;
2911 cmd[4] = datalen = 12;
2912 direction = DMA_TO_DEVICE;
2913
2914 memset((STp->buffer)->b_data, 0, 12);
2915 if (cmd_in == MTSETDRVBUFFER)
2916 (STp->buffer)->b_data[2] = (arg & 7) << 4;
2917 else
2918 (STp->buffer)->b_data[2] =
2919 STp->drv_buffer << 4;
2920 (STp->buffer)->b_data[3] = 8; /* block descriptor length */
2921 if (cmd_in == MTSETDENSITY) {
2922 (STp->buffer)->b_data[4] = arg;
2923 STp->density_changed = 1; /* At least we tried ;-) */
2924 } else if (cmd_in == SET_DENS_AND_BLK)
2925 (STp->buffer)->b_data[4] = arg >> 24;
2926 else
2927 (STp->buffer)->b_data[4] = STp->density;
2928 if (cmd_in == MTSETBLK || cmd_in == SET_DENS_AND_BLK) {
2929 ltmp = arg & MT_ST_BLKSIZE_MASK;
2930 if (cmd_in == MTSETBLK)
2931 STp->blksize_changed = 1; /* At least we tried ;-) */
2932 } else
2933 ltmp = STp->block_size;
2934 (STp->buffer)->b_data[9] = (ltmp >> 16);
2935 (STp->buffer)->b_data[10] = (ltmp >> 8);
2936 (STp->buffer)->b_data[11] = ltmp;
2937 timeout = STp->device->request_queue->rq_timeout;
2938 DEBC(
2939 if (cmd_in == MTSETBLK || cmd_in == SET_DENS_AND_BLK)
2940 st_printk(ST_DEB_MSG, STp,
2941 "Setting block size to %d bytes.\n",
2942 (STp->buffer)->b_data[9] * 65536 +
2943 (STp->buffer)->b_data[10] * 256 +
2944 (STp->buffer)->b_data[11]);
2945 if (cmd_in == MTSETDENSITY || cmd_in == SET_DENS_AND_BLK)
2946 st_printk(ST_DEB_MSG, STp,
2947 "Setting density code to %x.\n",
2948 (STp->buffer)->b_data[4]);
2949 if (cmd_in == MTSETDRVBUFFER)
2950 st_printk(ST_DEB_MSG, STp,
2951 "Setting drive buffer code to %d.\n",
2952 ((STp->buffer)->b_data[2] >> 4) & 7);
2953 )
2954 break;
2955 default:
2956 return (-ENOSYS);
2957 }
2958
2959 SRpnt = st_do_scsi(NULL, STp, cmd, datalen, direction,
2960 timeout, MAX_RETRIES, 1);
2961 if (!SRpnt)
2962 return (STp->buffer)->syscall_result;
2963
2964 ioctl_result = (STp->buffer)->syscall_result;
2965
2966 if (!ioctl_result) { /* SCSI command successful */
2967 st_release_request(SRpnt);
2968 SRpnt = NULL;
2969 STps->drv_block = blkno;
2970 STps->drv_file = fileno;
2971 STps->at_sm = at_sm;
2972
2973 if (cmd_in == MTBSFM)
2974 ioctl_result = st_int_ioctl(STp, MTFSF, 1);
2975 else if (cmd_in == MTFSFM)
2976 ioctl_result = st_int_ioctl(STp, MTBSF, 1);
2977
2978 if (cmd_in == MTSETBLK || cmd_in == SET_DENS_AND_BLK) {
2979 STp->block_size = arg & MT_ST_BLKSIZE_MASK;
2980 if (STp->block_size != 0) {
2981 (STp->buffer)->buffer_blocks =
2982 (STp->buffer)->buffer_size / STp->block_size;
2983 }
2984 (STp->buffer)->buffer_bytes = (STp->buffer)->read_pointer = 0;
2985 if (cmd_in == SET_DENS_AND_BLK)
2986 STp->density = arg >> MT_ST_DENSITY_SHIFT;
2987 } else if (cmd_in == MTSETDRVBUFFER)
2988 STp->drv_buffer = (arg & 7);
2989 else if (cmd_in == MTSETDENSITY)
2990 STp->density = arg;
2991
2992 if (cmd_in == MTEOM)
2993 STps->eof = ST_EOD;
2994 else if (cmd_in == MTFSF)
2995 STps->eof = ST_FM;
2996 else if (chg_eof)
2997 STps->eof = ST_NOEOF;
2998
2999 if (cmd_in == MTWEOF || cmd_in == MTWEOFI)
3000 STps->rw = ST_IDLE; /* prevent automatic WEOF at close */
3001 } else { /* SCSI command was not completely successful. Don't return
3002 from this block without releasing the SCSI command block! */
3003 struct st_cmdstatus *cmdstatp = &STp->buffer->cmdstat;
3004
3005 if (cmdstatp->flags & SENSE_EOM) {
3006 if (cmd_in != MTBSF && cmd_in != MTBSFM &&
3007 cmd_in != MTBSR && cmd_in != MTBSS)
3008 STps->eof = ST_EOM_OK;
3009 STps->drv_block = 0;
3010 }
3011
3012 if (cmdstatp->remainder_valid)
3013 undone = (int)cmdstatp->uremainder64;
3014 else
3015 undone = 0;
3016
3017 if ((cmd_in == MTWEOF || cmd_in == MTWEOFI) &&
3018 cmdstatp->have_sense &&
3019 (cmdstatp->flags & SENSE_EOM)) {
3020 if (cmdstatp->sense_hdr.sense_key == NO_SENSE ||
3021 cmdstatp->sense_hdr.sense_key == RECOVERED_ERROR) {
3022 ioctl_result = 0; /* EOF(s) written successfully at EOM */
3023 STps->eof = ST_NOEOF;
3024 } else { /* Writing EOF(s) failed */
3025 if (fileno >= 0)
3026 fileno -= undone;
3027 if (undone < arg)
3028 STps->eof = ST_NOEOF;
3029 }
3030 STps->drv_file = fileno;
3031 } else if ((cmd_in == MTFSF) || (cmd_in == MTFSFM)) {
3032 if (fileno >= 0)
3033 STps->drv_file = fileno - undone;
3034 else
3035 STps->drv_file = fileno;
3036 STps->drv_block = -1;
3037 STps->eof = ST_NOEOF;
3038 } else if ((cmd_in == MTBSF) || (cmd_in == MTBSFM)) {
3039 if (arg > 0 && undone < 0) /* Some drives get this wrong */
3040 undone = (-undone);
3041 if (STps->drv_file >= 0)
3042 STps->drv_file = fileno + undone;
3043 STps->drv_block = 0;
3044 STps->eof = ST_NOEOF;
3045 } else if (cmd_in == MTFSR) {
3046 if (cmdstatp->flags & SENSE_FMK) { /* Hit filemark */
3047 if (STps->drv_file >= 0)
3048 STps->drv_file++;
3049 STps->drv_block = 0;
3050 STps->eof = ST_FM;
3051 } else {
3052 if (blkno >= undone)
3053 STps->drv_block = blkno - undone;
3054 else
3055 STps->drv_block = (-1);
3056 STps->eof = ST_NOEOF;
3057 }
3058 } else if (cmd_in == MTBSR) {
3059 if (cmdstatp->flags & SENSE_FMK) { /* Hit filemark */
3060 STps->drv_file--;
3061 STps->drv_block = (-1);
3062 } else {
3063 if (arg > 0 && undone < 0) /* Some drives get this wrong */
3064 undone = (-undone);
3065 if (STps->drv_block >= 0)
3066 STps->drv_block = blkno + undone;
3067 }
3068 STps->eof = ST_NOEOF;
3069 } else if (cmd_in == MTEOM) {
3070 STps->drv_file = (-1);
3071 STps->drv_block = (-1);
3072 STps->eof = ST_EOD;
3073 } else if (cmd_in == MTSETBLK ||
3074 cmd_in == MTSETDENSITY ||
3075 cmd_in == MTSETDRVBUFFER ||
3076 cmd_in == SET_DENS_AND_BLK) {
3077 if (cmdstatp->sense_hdr.sense_key == ILLEGAL_REQUEST &&
3078 !(STp->use_pf & PF_TESTED)) {
3079 /* Try the other possible state of Page Format if not
3080 already tried */
3081 STp->use_pf = (STp->use_pf ^ USE_PF) | PF_TESTED;
3082 st_release_request(SRpnt);
3083 SRpnt = NULL;
3084 return st_int_ioctl(STp, cmd_in, arg);
3085 }
3086 } else if (chg_eof)
3087 STps->eof = ST_NOEOF;
3088
3089 if (cmdstatp->sense_hdr.sense_key == BLANK_CHECK)
3090 STps->eof = ST_EOD;
3091
3092 st_release_request(SRpnt);
3093 SRpnt = NULL;
3094 }
3095
3096 return ioctl_result;
3097 }
3098
3099
3100 /* Get the tape position. If bt == 2, arg points into a kernel space mt_loc
3101 structure. */
3102
get_location(struct scsi_tape * STp,unsigned int * block,int * partition,int logical)3103 static int get_location(struct scsi_tape *STp, unsigned int *block, int *partition,
3104 int logical)
3105 {
3106 int result;
3107 unsigned char scmd[MAX_COMMAND_SIZE];
3108 struct st_request *SRpnt;
3109
3110 if (STp->ready != ST_READY)
3111 return (-EIO);
3112
3113 memset(scmd, 0, MAX_COMMAND_SIZE);
3114 if ((STp->device)->scsi_level < SCSI_2) {
3115 scmd[0] = QFA_REQUEST_BLOCK;
3116 scmd[4] = 3;
3117 } else {
3118 scmd[0] = READ_POSITION;
3119 if (!logical && !STp->scsi2_logical)
3120 scmd[1] = 1;
3121 }
3122 SRpnt = st_do_scsi(NULL, STp, scmd, 20, DMA_FROM_DEVICE,
3123 STp->device->request_queue->rq_timeout,
3124 MAX_READY_RETRIES, 1);
3125 if (!SRpnt)
3126 return (STp->buffer)->syscall_result;
3127
3128 if ((STp->buffer)->syscall_result != 0 ||
3129 (STp->device->scsi_level >= SCSI_2 &&
3130 ((STp->buffer)->b_data[0] & 4) != 0)) {
3131 *block = *partition = 0;
3132 DEBC_printk(STp, " Can't read tape position.\n");
3133 result = (-EIO);
3134 } else {
3135 result = 0;
3136 if ((STp->device)->scsi_level < SCSI_2) {
3137 *block = ((STp->buffer)->b_data[0] << 16)
3138 + ((STp->buffer)->b_data[1] << 8)
3139 + (STp->buffer)->b_data[2];
3140 *partition = 0;
3141 } else {
3142 *block = ((STp->buffer)->b_data[4] << 24)
3143 + ((STp->buffer)->b_data[5] << 16)
3144 + ((STp->buffer)->b_data[6] << 8)
3145 + (STp->buffer)->b_data[7];
3146 *partition = (STp->buffer)->b_data[1];
3147 if (((STp->buffer)->b_data[0] & 0x80) &&
3148 (STp->buffer)->b_data[1] == 0) /* BOP of partition 0 */
3149 STp->ps[0].drv_block = STp->ps[0].drv_file = 0;
3150 }
3151 DEBC_printk(STp, "Got tape pos. blk %d part %d.\n",
3152 *block, *partition);
3153 }
3154 st_release_request(SRpnt);
3155 SRpnt = NULL;
3156
3157 return result;
3158 }
3159
3160
3161 /* Set the tape block and partition. Negative partition means that only the
3162 block should be set in vendor specific way. */
set_location(struct scsi_tape * STp,unsigned int block,int partition,int logical)3163 static int set_location(struct scsi_tape *STp, unsigned int block, int partition,
3164 int logical)
3165 {
3166 struct st_partstat *STps;
3167 int result, p;
3168 unsigned int blk;
3169 int timeout;
3170 unsigned char scmd[MAX_COMMAND_SIZE];
3171 struct st_request *SRpnt;
3172
3173 if (STp->ready != ST_READY)
3174 return (-EIO);
3175 timeout = STp->long_timeout;
3176 STps = &(STp->ps[STp->partition]);
3177
3178 DEBC_printk(STp, "Setting block to %d and partition to %d.\n",
3179 block, partition);
3180 DEB(if (partition < 0)
3181 return (-EIO); )
3182
3183 /* Update the location at the partition we are leaving */
3184 if ((!STp->can_partitions && partition != 0) ||
3185 partition >= ST_NBR_PARTITIONS)
3186 return (-EINVAL);
3187 if (partition != STp->partition) {
3188 if (get_location(STp, &blk, &p, 1))
3189 STps->last_block_valid = 0;
3190 else {
3191 STps->last_block_valid = 1;
3192 STps->last_block_visited = blk;
3193 DEBC_printk(STp, "Visited block %d for "
3194 "partition %d saved.\n",
3195 blk, STp->partition);
3196 }
3197 }
3198
3199 memset(scmd, 0, MAX_COMMAND_SIZE);
3200 if ((STp->device)->scsi_level < SCSI_2) {
3201 scmd[0] = QFA_SEEK_BLOCK;
3202 scmd[2] = (block >> 16);
3203 scmd[3] = (block >> 8);
3204 scmd[4] = block;
3205 scmd[5] = 0;
3206 } else {
3207 scmd[0] = SEEK_10;
3208 scmd[3] = (block >> 24);
3209 scmd[4] = (block >> 16);
3210 scmd[5] = (block >> 8);
3211 scmd[6] = block;
3212 if (!logical && !STp->scsi2_logical)
3213 scmd[1] = 4;
3214 if (STp->partition != partition) {
3215 scmd[1] |= 2;
3216 scmd[8] = partition;
3217 DEBC_printk(STp, "Trying to change partition "
3218 "from %d to %d\n", STp->partition,
3219 partition);
3220 }
3221 }
3222 if (STp->immediate) {
3223 scmd[1] |= 1; /* Don't wait for completion */
3224 timeout = STp->device->request_queue->rq_timeout;
3225 }
3226
3227 SRpnt = st_do_scsi(NULL, STp, scmd, 0, DMA_NONE,
3228 timeout, MAX_READY_RETRIES, 1);
3229 if (!SRpnt)
3230 return (STp->buffer)->syscall_result;
3231
3232 STps->drv_block = STps->drv_file = (-1);
3233 STps->eof = ST_NOEOF;
3234 if ((STp->buffer)->syscall_result != 0) {
3235 result = (-EIO);
3236 if (STp->can_partitions &&
3237 (STp->device)->scsi_level >= SCSI_2 &&
3238 (p = find_partition(STp)) >= 0)
3239 STp->partition = p;
3240 } else {
3241 if (STp->can_partitions) {
3242 STp->partition = partition;
3243 STps = &(STp->ps[partition]);
3244 if (!STps->last_block_valid ||
3245 STps->last_block_visited != block) {
3246 STps->at_sm = 0;
3247 STps->rw = ST_IDLE;
3248 }
3249 } else
3250 STps->at_sm = 0;
3251 if (block == 0)
3252 STps->drv_block = STps->drv_file = 0;
3253 result = 0;
3254 }
3255
3256 st_release_request(SRpnt);
3257 SRpnt = NULL;
3258
3259 return result;
3260 }
3261
3262
3263 /* Find the current partition number for the drive status. Called from open and
3264 returns either partition number of negative error code. */
find_partition(struct scsi_tape * STp)3265 static int find_partition(struct scsi_tape *STp)
3266 {
3267 int i, partition;
3268 unsigned int block;
3269
3270 if ((i = get_location(STp, &block, &partition, 1)) < 0)
3271 return i;
3272 if (partition >= ST_NBR_PARTITIONS)
3273 return (-EIO);
3274 return partition;
3275 }
3276
3277
3278 /* Change the partition if necessary */
switch_partition(struct scsi_tape * STp)3279 static int switch_partition(struct scsi_tape *STp)
3280 {
3281 struct st_partstat *STps;
3282
3283 if (STp->partition == STp->new_partition)
3284 return 0;
3285 STps = &(STp->ps[STp->new_partition]);
3286 if (!STps->last_block_valid)
3287 STps->last_block_visited = 0;
3288 return set_location(STp, STps->last_block_visited, STp->new_partition, 1);
3289 }
3290
3291 /* Functions for reading and writing the medium partition mode page. */
3292
3293 #define PART_PAGE 0x11
3294 #define PART_PAGE_FIXED_LENGTH 8
3295
3296 #define PP_OFF_MAX_ADD_PARTS 2
3297 #define PP_OFF_NBR_ADD_PARTS 3
3298 #define PP_OFF_FLAGS 4
3299 #define PP_OFF_PART_UNITS 6
3300 #define PP_OFF_RESERVED 7
3301
3302 #define PP_BIT_IDP 0x20
3303 #define PP_BIT_FDP 0x80
3304 #define PP_MSK_PSUM_MB 0x10
3305 #define PP_MSK_PSUM_UNITS 0x18
3306 #define PP_MSK_POFM 0x04
3307
3308 /* Get the number of partitions on the tape. As a side effect reads the
3309 mode page into the tape buffer. */
nbr_partitions(struct scsi_tape * STp)3310 static int nbr_partitions(struct scsi_tape *STp)
3311 {
3312 int result;
3313
3314 if (STp->ready != ST_READY)
3315 return (-EIO);
3316
3317 result = read_mode_page(STp, PART_PAGE, 1);
3318
3319 if (result) {
3320 DEBC_printk(STp, "Can't read medium partition page.\n");
3321 result = (-EIO);
3322 } else {
3323 result = (STp->buffer)->b_data[MODE_HEADER_LENGTH +
3324 PP_OFF_NBR_ADD_PARTS] + 1;
3325 DEBC_printk(STp, "Number of partitions %d.\n", result);
3326 }
3327
3328 return result;
3329 }
3330
3331
format_medium(struct scsi_tape * STp,int format)3332 static int format_medium(struct scsi_tape *STp, int format)
3333 {
3334 int result = 0;
3335 int timeout = STp->long_timeout;
3336 unsigned char scmd[MAX_COMMAND_SIZE];
3337 struct st_request *SRpnt;
3338
3339 memset(scmd, 0, MAX_COMMAND_SIZE);
3340 scmd[0] = FORMAT_UNIT;
3341 scmd[2] = format;
3342 if (STp->immediate) {
3343 scmd[1] |= 1; /* Don't wait for completion */
3344 timeout = STp->device->request_queue->rq_timeout;
3345 }
3346 DEBC_printk(STp, "Sending FORMAT MEDIUM\n");
3347 SRpnt = st_do_scsi(NULL, STp, scmd, 0, DMA_NONE,
3348 timeout, MAX_RETRIES, 1);
3349 if (!SRpnt)
3350 result = STp->buffer->syscall_result;
3351 return result;
3352 }
3353
3354
3355 /* Partition the tape into two partitions if size > 0 or one partition if
3356 size == 0.
3357
3358 The block descriptors are read and written because Sony SDT-7000 does not
3359 work without this (suggestion from Michael Schaefer <Michael.Schaefer@dlr.de>).
3360
3361 My HP C1533A drive returns only one partition size field. This is used to
3362 set the size of partition 1. There is no size field for the default partition.
3363 Michael Schaefer's Sony SDT-7000 returns two descriptors and the second is
3364 used to set the size of partition 1 (this is what the SCSI-3 standard specifies).
3365 The following algorithm is used to accommodate both drives: if the number of
3366 partition size fields is greater than the maximum number of additional partitions
3367 in the mode page, the second field is used. Otherwise the first field is used.
3368
3369 For Seagate DDS drives the page length must be 8 when no partitions is defined
3370 and 10 when 1 partition is defined (information from Eric Lee Green). This is
3371 is acceptable also to some other old drives and enforced if the first partition
3372 size field is used for the first additional partition size.
3373
3374 For drives that advertize SCSI-3 or newer, use the SSC-3 methods.
3375 */
partition_tape(struct scsi_tape * STp,int size)3376 static int partition_tape(struct scsi_tape *STp, int size)
3377 {
3378 int result;
3379 int target_partition;
3380 bool scsi3 = STp->device->scsi_level >= SCSI_3, needs_format = false;
3381 int pgo, psd_cnt, psdo;
3382 int psum = PP_MSK_PSUM_MB, units = 0;
3383 unsigned char *bp;
3384
3385 result = read_mode_page(STp, PART_PAGE, 0);
3386 if (result) {
3387 DEBC_printk(STp, "Can't read partition mode page.\n");
3388 return result;
3389 }
3390 target_partition = 1;
3391 if (size < 0) {
3392 target_partition = 0;
3393 size = -size;
3394 }
3395
3396 /* The mode page is in the buffer. Let's modify it and write it. */
3397 bp = (STp->buffer)->b_data;
3398 pgo = MODE_HEADER_LENGTH + bp[MH_OFF_BDESCS_LENGTH];
3399 DEBC_printk(STp, "Partition page length is %d bytes.\n",
3400 bp[pgo + MP_OFF_PAGE_LENGTH] + 2);
3401
3402 psd_cnt = (bp[pgo + MP_OFF_PAGE_LENGTH] + 2 - PART_PAGE_FIXED_LENGTH) / 2;
3403
3404 if (scsi3) {
3405 needs_format = (bp[pgo + PP_OFF_FLAGS] & PP_MSK_POFM) != 0;
3406 if (needs_format && size == 0) {
3407 /* No need to write the mode page when clearing
3408 * partitioning
3409 */
3410 DEBC_printk(STp, "Formatting tape with one partition.\n");
3411 result = format_medium(STp, 0);
3412 goto out;
3413 }
3414 if (needs_format) /* Leave the old value for HP DATs claiming SCSI_3 */
3415 psd_cnt = 2;
3416 if ((bp[pgo + PP_OFF_FLAGS] & PP_MSK_PSUM_UNITS) == PP_MSK_PSUM_UNITS) {
3417 /* Use units scaling for large partitions if the device
3418 * suggests it and no precision lost. Required for IBM
3419 * TS1140/50 drives that don't support MB units.
3420 */
3421 if (size >= 1000 && (size % 1000) == 0) {
3422 size /= 1000;
3423 psum = PP_MSK_PSUM_UNITS;
3424 units = 9; /* GB */
3425 }
3426 }
3427 /* Try it anyway if too large to specify in MB */
3428 if (psum == PP_MSK_PSUM_MB && size >= 65534) {
3429 size /= 1000;
3430 psum = PP_MSK_PSUM_UNITS;
3431 units = 9; /* GB */
3432 }
3433 }
3434
3435 if (size >= 65535 || /* Does not fit into two bytes */
3436 (target_partition == 0 && psd_cnt < 2)) {
3437 result = -EINVAL;
3438 goto out;
3439 }
3440
3441 psdo = pgo + PART_PAGE_FIXED_LENGTH;
3442 /* The second condition is for HP DDS which use only one partition size
3443 * descriptor
3444 */
3445 if (target_partition > 0 &&
3446 (psd_cnt > bp[pgo + PP_OFF_MAX_ADD_PARTS] ||
3447 bp[pgo + PP_OFF_MAX_ADD_PARTS] != 1)) {
3448 bp[psdo] = bp[psdo + 1] = 0xff; /* Rest to partition 0 */
3449 psdo += 2;
3450 }
3451 memset(bp + psdo, 0, bp[pgo + PP_OFF_NBR_ADD_PARTS] * 2);
3452
3453 DEBC_printk(STp, "psd_cnt %d, max.parts %d, nbr_parts %d\n",
3454 psd_cnt, bp[pgo + PP_OFF_MAX_ADD_PARTS],
3455 bp[pgo + PP_OFF_NBR_ADD_PARTS]);
3456
3457 if (size == 0) {
3458 bp[pgo + PP_OFF_NBR_ADD_PARTS] = 0;
3459 if (psd_cnt <= bp[pgo + PP_OFF_MAX_ADD_PARTS])
3460 bp[pgo + MP_OFF_PAGE_LENGTH] = 6;
3461 DEBC_printk(STp, "Formatting tape with one partition.\n");
3462 } else {
3463 bp[psdo] = (size >> 8) & 0xff;
3464 bp[psdo + 1] = size & 0xff;
3465 if (target_partition == 0)
3466 bp[psdo + 2] = bp[psdo + 3] = 0xff;
3467 bp[pgo + 3] = 1;
3468 if (bp[pgo + MP_OFF_PAGE_LENGTH] < 8)
3469 bp[pgo + MP_OFF_PAGE_LENGTH] = 8;
3470 DEBC_printk(STp,
3471 "Formatting tape with two partitions (%i = %d MB).\n",
3472 target_partition, units > 0 ? size * 1000 : size);
3473 }
3474 bp[pgo + PP_OFF_PART_UNITS] = 0;
3475 bp[pgo + PP_OFF_RESERVED] = 0;
3476 if (size != 1 || units != 0) {
3477 bp[pgo + PP_OFF_FLAGS] = PP_BIT_IDP | psum |
3478 (bp[pgo + PP_OFF_FLAGS] & 0x07);
3479 bp[pgo + PP_OFF_PART_UNITS] = units;
3480 } else
3481 bp[pgo + PP_OFF_FLAGS] = PP_BIT_FDP |
3482 (bp[pgo + PP_OFF_FLAGS] & 0x1f);
3483 bp[pgo + MP_OFF_PAGE_LENGTH] = 6 + psd_cnt * 2;
3484
3485 result = write_mode_page(STp, PART_PAGE, 1);
3486
3487 if (!result && needs_format)
3488 result = format_medium(STp, 1);
3489
3490 if (result) {
3491 st_printk(KERN_INFO, STp, "Partitioning of tape failed.\n");
3492 result = (-EIO);
3493 }
3494
3495 out:
3496 return result;
3497 }
3498
3499
3500
3501 /* The ioctl command */
st_ioctl_common(struct file * file,unsigned int cmd_in,void __user * p)3502 static long st_ioctl_common(struct file *file, unsigned int cmd_in, void __user *p)
3503 {
3504 int i, cmd_nr, cmd_type, bt;
3505 int retval = 0;
3506 unsigned int blk;
3507 struct scsi_tape *STp = file->private_data;
3508 struct st_modedef *STm;
3509 struct st_partstat *STps;
3510
3511 if (mutex_lock_interruptible(&STp->lock))
3512 return -ERESTARTSYS;
3513
3514 DEB(
3515 if (debugging && !STp->in_use) {
3516 st_printk(ST_DEB_MSG, STp, "Incorrect device.\n");
3517 retval = (-EIO);
3518 goto out;
3519 } ) /* end DEB */
3520
3521 STm = &(STp->modes[STp->current_mode]);
3522 STps = &(STp->ps[STp->partition]);
3523
3524 /*
3525 * If we are in the middle of error recovery, don't let anyone
3526 * else try and use this device. Also, if error recovery fails, it
3527 * may try and take the device offline, in which case all further
3528 * access to the device is prohibited.
3529 */
3530 retval = scsi_ioctl_block_when_processing_errors(STp->device, cmd_in,
3531 file->f_flags & O_NDELAY);
3532 if (retval)
3533 goto out;
3534
3535 cmd_type = _IOC_TYPE(cmd_in);
3536 cmd_nr = _IOC_NR(cmd_in);
3537
3538 if (cmd_type == _IOC_TYPE(MTIOCTOP) && cmd_nr == _IOC_NR(MTIOCTOP)) {
3539 struct mtop mtc;
3540
3541 if (_IOC_SIZE(cmd_in) != sizeof(mtc)) {
3542 retval = (-EINVAL);
3543 goto out;
3544 }
3545
3546 i = copy_from_user(&mtc, p, sizeof(struct mtop));
3547 if (i) {
3548 retval = (-EFAULT);
3549 goto out;
3550 }
3551
3552 if (mtc.mt_op == MTSETDRVBUFFER && !capable(CAP_SYS_ADMIN)) {
3553 st_printk(KERN_WARNING, STp,
3554 "MTSETDRVBUFFER only allowed for root.\n");
3555 retval = (-EPERM);
3556 goto out;
3557 }
3558 if (!STm->defined &&
3559 (mtc.mt_op != MTSETDRVBUFFER &&
3560 (mtc.mt_count & MT_ST_OPTIONS) == 0)) {
3561 retval = (-ENXIO);
3562 goto out;
3563 }
3564
3565 if (!STp->pos_unknown) {
3566
3567 if (STps->eof == ST_FM_HIT) {
3568 if (mtc.mt_op == MTFSF || mtc.mt_op == MTFSFM ||
3569 mtc.mt_op == MTEOM) {
3570 mtc.mt_count -= 1;
3571 if (STps->drv_file >= 0)
3572 STps->drv_file += 1;
3573 } else if (mtc.mt_op == MTBSF || mtc.mt_op == MTBSFM) {
3574 mtc.mt_count += 1;
3575 if (STps->drv_file >= 0)
3576 STps->drv_file += 1;
3577 }
3578 }
3579
3580 if (mtc.mt_op == MTSEEK) {
3581 /* Old position must be restored if partition will be
3582 changed */
3583 i = !STp->can_partitions ||
3584 (STp->new_partition != STp->partition);
3585 } else {
3586 i = mtc.mt_op == MTREW || mtc.mt_op == MTOFFL ||
3587 mtc.mt_op == MTRETEN || mtc.mt_op == MTEOM ||
3588 mtc.mt_op == MTLOCK || mtc.mt_op == MTLOAD ||
3589 mtc.mt_op == MTFSF || mtc.mt_op == MTFSFM ||
3590 mtc.mt_op == MTBSF || mtc.mt_op == MTBSFM ||
3591 mtc.mt_op == MTCOMPRESSION;
3592 }
3593 i = flush_buffer(STp, i);
3594 if (i < 0) {
3595 retval = i;
3596 goto out;
3597 }
3598 if (STps->rw == ST_WRITING &&
3599 (mtc.mt_op == MTREW || mtc.mt_op == MTOFFL ||
3600 mtc.mt_op == MTSEEK ||
3601 mtc.mt_op == MTBSF || mtc.mt_op == MTBSFM)) {
3602 i = st_int_ioctl(STp, MTWEOF, 1);
3603 if (i < 0) {
3604 retval = i;
3605 goto out;
3606 }
3607 if (mtc.mt_op == MTBSF || mtc.mt_op == MTBSFM)
3608 mtc.mt_count++;
3609 STps->rw = ST_IDLE;
3610 }
3611
3612 } else {
3613 /*
3614 * If there was a bus reset, block further access
3615 * to this device. If the user wants to rewind the tape,
3616 * then reset the flag and allow access again.
3617 */
3618 if (mtc.mt_op != MTREW &&
3619 mtc.mt_op != MTOFFL &&
3620 mtc.mt_op != MTRETEN &&
3621 mtc.mt_op != MTERASE &&
3622 mtc.mt_op != MTSEEK &&
3623 mtc.mt_op != MTEOM) {
3624 retval = (-EIO);
3625 goto out;
3626 }
3627 reset_state(STp);
3628 /* remove this when the midlevel properly clears was_reset */
3629 STp->device->was_reset = 0;
3630 }
3631
3632 if (mtc.mt_op != MTNOP && mtc.mt_op != MTSETBLK &&
3633 mtc.mt_op != MTSETDENSITY && mtc.mt_op != MTWSM &&
3634 mtc.mt_op != MTSETDRVBUFFER && mtc.mt_op != MTSETPART)
3635 STps->rw = ST_IDLE; /* Prevent automatic WEOF and fsf */
3636
3637 if (mtc.mt_op == MTOFFL && STp->door_locked != ST_UNLOCKED)
3638 do_door_lock(STp, 0); /* Ignore result! */
3639
3640 if (mtc.mt_op == MTSETDRVBUFFER &&
3641 (mtc.mt_count & MT_ST_OPTIONS) != 0) {
3642 retval = st_set_options(STp, mtc.mt_count);
3643 goto out;
3644 }
3645
3646 if (mtc.mt_op == MTSETPART) {
3647 if (!STp->can_partitions ||
3648 mtc.mt_count < 0 || mtc.mt_count >= ST_NBR_PARTITIONS) {
3649 retval = (-EINVAL);
3650 goto out;
3651 }
3652 if (mtc.mt_count >= STp->nbr_partitions &&
3653 (STp->nbr_partitions = nbr_partitions(STp)) < 0) {
3654 retval = (-EIO);
3655 goto out;
3656 }
3657 if (mtc.mt_count >= STp->nbr_partitions) {
3658 retval = (-EINVAL);
3659 goto out;
3660 }
3661 STp->new_partition = mtc.mt_count;
3662 retval = 0;
3663 goto out;
3664 }
3665
3666 if (mtc.mt_op == MTMKPART) {
3667 if (!STp->can_partitions) {
3668 retval = (-EINVAL);
3669 goto out;
3670 }
3671 i = do_load_unload(STp, file, 1);
3672 if (i < 0) {
3673 retval = i;
3674 goto out;
3675 }
3676 i = partition_tape(STp, mtc.mt_count);
3677 if (i < 0) {
3678 retval = i;
3679 goto out;
3680 }
3681 for (i = 0; i < ST_NBR_PARTITIONS; i++) {
3682 STp->ps[i].rw = ST_IDLE;
3683 STp->ps[i].at_sm = 0;
3684 STp->ps[i].last_block_valid = 0;
3685 }
3686 STp->partition = STp->new_partition = 0;
3687 STp->nbr_partitions = mtc.mt_count != 0 ? 2 : 1;
3688 STps->drv_block = STps->drv_file = 0;
3689 retval = 0;
3690 goto out;
3691 }
3692
3693 if (mtc.mt_op == MTSEEK) {
3694 i = set_location(STp, mtc.mt_count, STp->new_partition, 0);
3695 if (!STp->can_partitions)
3696 STp->ps[0].rw = ST_IDLE;
3697 retval = i;
3698 goto out;
3699 }
3700
3701 if (mtc.mt_op == MTUNLOAD || mtc.mt_op == MTOFFL) {
3702 retval = do_load_unload(STp, file, 0);
3703 goto out;
3704 }
3705
3706 if (mtc.mt_op == MTLOAD) {
3707 retval = do_load_unload(STp, file, max(1, mtc.mt_count));
3708 goto out;
3709 }
3710
3711 if (mtc.mt_op == MTLOCK || mtc.mt_op == MTUNLOCK) {
3712 retval = do_door_lock(STp, (mtc.mt_op == MTLOCK));
3713 goto out;
3714 }
3715
3716 if (STp->can_partitions && STp->ready == ST_READY &&
3717 (i = switch_partition(STp)) < 0) {
3718 retval = i;
3719 goto out;
3720 }
3721
3722 if (mtc.mt_op == MTCOMPRESSION)
3723 retval = st_compression(STp, (mtc.mt_count & 1));
3724 else
3725 retval = st_int_ioctl(STp, mtc.mt_op, mtc.mt_count);
3726 goto out;
3727 }
3728 if (!STm->defined) {
3729 retval = (-ENXIO);
3730 goto out;
3731 }
3732
3733 if ((i = flush_buffer(STp, 0)) < 0) {
3734 retval = i;
3735 goto out;
3736 }
3737 if (STp->can_partitions &&
3738 (i = switch_partition(STp)) < 0) {
3739 retval = i;
3740 goto out;
3741 }
3742
3743 if (cmd_type == _IOC_TYPE(MTIOCGET) && cmd_nr == _IOC_NR(MTIOCGET)) {
3744 struct mtget mt_status;
3745
3746 if (_IOC_SIZE(cmd_in) != sizeof(struct mtget)) {
3747 retval = (-EINVAL);
3748 goto out;
3749 }
3750
3751 mt_status.mt_type = STp->tape_type;
3752 mt_status.mt_dsreg =
3753 ((STp->block_size << MT_ST_BLKSIZE_SHIFT) & MT_ST_BLKSIZE_MASK) |
3754 ((STp->density << MT_ST_DENSITY_SHIFT) & MT_ST_DENSITY_MASK);
3755 mt_status.mt_blkno = STps->drv_block;
3756 mt_status.mt_fileno = STps->drv_file;
3757 if (STp->block_size != 0) {
3758 if (STps->rw == ST_WRITING)
3759 mt_status.mt_blkno +=
3760 (STp->buffer)->buffer_bytes / STp->block_size;
3761 else if (STps->rw == ST_READING)
3762 mt_status.mt_blkno -=
3763 ((STp->buffer)->buffer_bytes +
3764 STp->block_size - 1) / STp->block_size;
3765 }
3766
3767 mt_status.mt_gstat = 0;
3768 if (STp->drv_write_prot)
3769 mt_status.mt_gstat |= GMT_WR_PROT(0xffffffff);
3770 if (mt_status.mt_blkno == 0) {
3771 if (mt_status.mt_fileno == 0)
3772 mt_status.mt_gstat |= GMT_BOT(0xffffffff);
3773 else
3774 mt_status.mt_gstat |= GMT_EOF(0xffffffff);
3775 }
3776 mt_status.mt_erreg = (STp->recover_reg << MT_ST_SOFTERR_SHIFT);
3777 mt_status.mt_resid = STp->partition;
3778 if (STps->eof == ST_EOM_OK || STps->eof == ST_EOM_ERROR)
3779 mt_status.mt_gstat |= GMT_EOT(0xffffffff);
3780 else if (STps->eof >= ST_EOM_OK)
3781 mt_status.mt_gstat |= GMT_EOD(0xffffffff);
3782 if (STp->density == 1)
3783 mt_status.mt_gstat |= GMT_D_800(0xffffffff);
3784 else if (STp->density == 2)
3785 mt_status.mt_gstat |= GMT_D_1600(0xffffffff);
3786 else if (STp->density == 3)
3787 mt_status.mt_gstat |= GMT_D_6250(0xffffffff);
3788 if (STp->ready == ST_READY)
3789 mt_status.mt_gstat |= GMT_ONLINE(0xffffffff);
3790 if (STp->ready == ST_NO_TAPE)
3791 mt_status.mt_gstat |= GMT_DR_OPEN(0xffffffff);
3792 if (STps->at_sm)
3793 mt_status.mt_gstat |= GMT_SM(0xffffffff);
3794 if (STm->do_async_writes ||
3795 (STm->do_buffer_writes && STp->block_size != 0) ||
3796 STp->drv_buffer != 0)
3797 mt_status.mt_gstat |= GMT_IM_REP_EN(0xffffffff);
3798 if (STp->cleaning_req)
3799 mt_status.mt_gstat |= GMT_CLN(0xffffffff);
3800
3801 retval = put_user_mtget(p, &mt_status);
3802 if (retval)
3803 goto out;
3804
3805 STp->recover_reg = 0; /* Clear after read */
3806 goto out;
3807 } /* End of MTIOCGET */
3808 if (cmd_type == _IOC_TYPE(MTIOCPOS) && cmd_nr == _IOC_NR(MTIOCPOS)) {
3809 struct mtpos mt_pos;
3810 if (_IOC_SIZE(cmd_in) != sizeof(struct mtpos)) {
3811 retval = (-EINVAL);
3812 goto out;
3813 }
3814 if ((i = get_location(STp, &blk, &bt, 0)) < 0) {
3815 retval = i;
3816 goto out;
3817 }
3818 mt_pos.mt_blkno = blk;
3819 retval = put_user_mtpos(p, &mt_pos);
3820 goto out;
3821 }
3822 mutex_unlock(&STp->lock);
3823 switch (cmd_in) {
3824 case SCSI_IOCTL_STOP_UNIT:
3825 /* unload */
3826 retval = scsi_ioctl(STp->device, cmd_in, p);
3827 if (!retval) {
3828 STp->rew_at_close = 0;
3829 STp->ready = ST_NO_TAPE;
3830 }
3831 return retval;
3832
3833 case SCSI_IOCTL_GET_IDLUN:
3834 case SCSI_IOCTL_GET_BUS_NUMBER:
3835 break;
3836
3837 default:
3838 if ((cmd_in == SG_IO ||
3839 cmd_in == SCSI_IOCTL_SEND_COMMAND ||
3840 cmd_in == CDROM_SEND_PACKET) &&
3841 !capable(CAP_SYS_RAWIO))
3842 i = -EPERM;
3843 else
3844 i = scsi_cmd_ioctl(STp->disk->queue, STp->disk,
3845 file->f_mode, cmd_in, p);
3846 if (i != -ENOTTY)
3847 return i;
3848 break;
3849 }
3850 return -ENOTTY;
3851
3852 out:
3853 mutex_unlock(&STp->lock);
3854 return retval;
3855 }
3856
st_ioctl(struct file * file,unsigned int cmd_in,unsigned long arg)3857 static long st_ioctl(struct file *file, unsigned int cmd_in, unsigned long arg)
3858 {
3859 void __user *p = (void __user *)arg;
3860 struct scsi_tape *STp = file->private_data;
3861 int ret;
3862
3863 ret = st_ioctl_common(file, cmd_in, p);
3864 if (ret != -ENOTTY)
3865 return ret;
3866
3867 return scsi_ioctl(STp->device, cmd_in, p);
3868 }
3869
3870 #ifdef CONFIG_COMPAT
st_compat_ioctl(struct file * file,unsigned int cmd_in,unsigned long arg)3871 static long st_compat_ioctl(struct file *file, unsigned int cmd_in, unsigned long arg)
3872 {
3873 void __user *p = compat_ptr(arg);
3874 struct scsi_tape *STp = file->private_data;
3875 int ret;
3876
3877 /* argument conversion is handled using put_user_mtpos/put_user_mtget */
3878 switch (cmd_in) {
3879 case MTIOCPOS32:
3880 return st_ioctl_common(file, MTIOCPOS, p);
3881 case MTIOCGET32:
3882 return st_ioctl_common(file, MTIOCGET, p);
3883 }
3884
3885 ret = st_ioctl_common(file, cmd_in, p);
3886 if (ret != -ENOTTY)
3887 return ret;
3888
3889 return scsi_compat_ioctl(STp->device, cmd_in, p);
3890 }
3891 #endif
3892
3893
3894
3895 /* Try to allocate a new tape buffer. Calling function must not hold
3896 dev_arr_lock. */
new_tape_buffer(int max_sg)3897 static struct st_buffer *new_tape_buffer(int max_sg)
3898 {
3899 struct st_buffer *tb;
3900
3901 tb = kzalloc(sizeof(struct st_buffer), GFP_KERNEL);
3902 if (!tb) {
3903 printk(KERN_NOTICE "st: Can't allocate new tape buffer.\n");
3904 return NULL;
3905 }
3906 tb->frp_segs = 0;
3907 tb->use_sg = max_sg;
3908 tb->buffer_size = 0;
3909
3910 tb->reserved_pages = kcalloc(max_sg, sizeof(struct page *),
3911 GFP_KERNEL);
3912 if (!tb->reserved_pages) {
3913 kfree(tb);
3914 return NULL;
3915 }
3916
3917 return tb;
3918 }
3919
3920
3921 /* Try to allocate enough space in the tape buffer */
3922 #define ST_MAX_ORDER 6
3923
enlarge_buffer(struct st_buffer * STbuffer,int new_size)3924 static int enlarge_buffer(struct st_buffer * STbuffer, int new_size)
3925 {
3926 int segs, max_segs, b_size, order, got;
3927 gfp_t priority;
3928
3929 if (new_size <= STbuffer->buffer_size)
3930 return 1;
3931
3932 if (STbuffer->buffer_size <= PAGE_SIZE)
3933 normalize_buffer(STbuffer); /* Avoid extra segment */
3934
3935 max_segs = STbuffer->use_sg;
3936
3937 priority = GFP_KERNEL | __GFP_NOWARN;
3938
3939 if (STbuffer->cleared)
3940 priority |= __GFP_ZERO;
3941
3942 if (STbuffer->frp_segs) {
3943 order = STbuffer->reserved_page_order;
3944 b_size = PAGE_SIZE << order;
3945 } else {
3946 for (b_size = PAGE_SIZE, order = 0;
3947 order < ST_MAX_ORDER &&
3948 max_segs * (PAGE_SIZE << order) < new_size;
3949 order++, b_size *= 2)
3950 ; /* empty */
3951 STbuffer->reserved_page_order = order;
3952 }
3953 if (max_segs * (PAGE_SIZE << order) < new_size) {
3954 if (order == ST_MAX_ORDER)
3955 return 0;
3956 normalize_buffer(STbuffer);
3957 return enlarge_buffer(STbuffer, new_size);
3958 }
3959
3960 for (segs = STbuffer->frp_segs, got = STbuffer->buffer_size;
3961 segs < max_segs && got < new_size;) {
3962 struct page *page;
3963
3964 page = alloc_pages(priority, order);
3965 if (!page) {
3966 DEB(STbuffer->buffer_size = got);
3967 normalize_buffer(STbuffer);
3968 return 0;
3969 }
3970
3971 STbuffer->frp_segs += 1;
3972 got += b_size;
3973 STbuffer->buffer_size = got;
3974 STbuffer->reserved_pages[segs] = page;
3975 segs++;
3976 }
3977 STbuffer->b_data = page_address(STbuffer->reserved_pages[0]);
3978
3979 return 1;
3980 }
3981
3982
3983 /* Make sure that no data from previous user is in the internal buffer */
clear_buffer(struct st_buffer * st_bp)3984 static void clear_buffer(struct st_buffer * st_bp)
3985 {
3986 int i;
3987
3988 for (i=0; i < st_bp->frp_segs; i++)
3989 memset(page_address(st_bp->reserved_pages[i]), 0,
3990 PAGE_SIZE << st_bp->reserved_page_order);
3991 st_bp->cleared = 1;
3992 }
3993
3994
3995 /* Release the extra buffer */
normalize_buffer(struct st_buffer * STbuffer)3996 static void normalize_buffer(struct st_buffer * STbuffer)
3997 {
3998 int i, order = STbuffer->reserved_page_order;
3999
4000 for (i = 0; i < STbuffer->frp_segs; i++) {
4001 __free_pages(STbuffer->reserved_pages[i], order);
4002 STbuffer->buffer_size -= (PAGE_SIZE << order);
4003 }
4004 STbuffer->frp_segs = 0;
4005 STbuffer->sg_segs = 0;
4006 STbuffer->reserved_page_order = 0;
4007 STbuffer->map_data.offset = 0;
4008 }
4009
4010
4011 /* Move data from the user buffer to the tape buffer. Returns zero (success) or
4012 negative error code. */
append_to_buffer(const char __user * ubp,struct st_buffer * st_bp,int do_count)4013 static int append_to_buffer(const char __user *ubp, struct st_buffer * st_bp, int do_count)
4014 {
4015 int i, cnt, res, offset;
4016 int length = PAGE_SIZE << st_bp->reserved_page_order;
4017
4018 for (i = 0, offset = st_bp->buffer_bytes;
4019 i < st_bp->frp_segs && offset >= length; i++)
4020 offset -= length;
4021 if (i == st_bp->frp_segs) { /* Should never happen */
4022 printk(KERN_WARNING "st: append_to_buffer offset overflow.\n");
4023 return (-EIO);
4024 }
4025 for (; i < st_bp->frp_segs && do_count > 0; i++) {
4026 struct page *page = st_bp->reserved_pages[i];
4027 cnt = length - offset < do_count ? length - offset : do_count;
4028 res = copy_from_user(page_address(page) + offset, ubp, cnt);
4029 if (res)
4030 return (-EFAULT);
4031 do_count -= cnt;
4032 st_bp->buffer_bytes += cnt;
4033 ubp += cnt;
4034 offset = 0;
4035 }
4036 if (do_count) /* Should never happen */
4037 return (-EIO);
4038
4039 return 0;
4040 }
4041
4042
4043 /* Move data from the tape buffer to the user buffer. Returns zero (success) or
4044 negative error code. */
from_buffer(struct st_buffer * st_bp,char __user * ubp,int do_count)4045 static int from_buffer(struct st_buffer * st_bp, char __user *ubp, int do_count)
4046 {
4047 int i, cnt, res, offset;
4048 int length = PAGE_SIZE << st_bp->reserved_page_order;
4049
4050 for (i = 0, offset = st_bp->read_pointer;
4051 i < st_bp->frp_segs && offset >= length; i++)
4052 offset -= length;
4053 if (i == st_bp->frp_segs) { /* Should never happen */
4054 printk(KERN_WARNING "st: from_buffer offset overflow.\n");
4055 return (-EIO);
4056 }
4057 for (; i < st_bp->frp_segs && do_count > 0; i++) {
4058 struct page *page = st_bp->reserved_pages[i];
4059 cnt = length - offset < do_count ? length - offset : do_count;
4060 res = copy_to_user(ubp, page_address(page) + offset, cnt);
4061 if (res)
4062 return (-EFAULT);
4063 do_count -= cnt;
4064 st_bp->buffer_bytes -= cnt;
4065 st_bp->read_pointer += cnt;
4066 ubp += cnt;
4067 offset = 0;
4068 }
4069 if (do_count) /* Should never happen */
4070 return (-EIO);
4071
4072 return 0;
4073 }
4074
4075
4076 /* Move data towards start of buffer */
move_buffer_data(struct st_buffer * st_bp,int offset)4077 static void move_buffer_data(struct st_buffer * st_bp, int offset)
4078 {
4079 int src_seg, dst_seg, src_offset = 0, dst_offset;
4080 int count, total;
4081 int length = PAGE_SIZE << st_bp->reserved_page_order;
4082
4083 if (offset == 0)
4084 return;
4085
4086 total=st_bp->buffer_bytes - offset;
4087 for (src_seg=0; src_seg < st_bp->frp_segs; src_seg++) {
4088 src_offset = offset;
4089 if (src_offset < length)
4090 break;
4091 offset -= length;
4092 }
4093
4094 st_bp->buffer_bytes = st_bp->read_pointer = total;
4095 for (dst_seg=dst_offset=0; total > 0; ) {
4096 struct page *dpage = st_bp->reserved_pages[dst_seg];
4097 struct page *spage = st_bp->reserved_pages[src_seg];
4098
4099 count = min(length - dst_offset, length - src_offset);
4100 memmove(page_address(dpage) + dst_offset,
4101 page_address(spage) + src_offset, count);
4102 src_offset += count;
4103 if (src_offset >= length) {
4104 src_seg++;
4105 src_offset = 0;
4106 }
4107 dst_offset += count;
4108 if (dst_offset >= length) {
4109 dst_seg++;
4110 dst_offset = 0;
4111 }
4112 total -= count;
4113 }
4114 }
4115
4116 /* Validate the options from command line or module parameters */
validate_options(void)4117 static void validate_options(void)
4118 {
4119 if (buffer_kbs > 0)
4120 st_fixed_buffer_size = buffer_kbs * ST_KILOBYTE;
4121 if (max_sg_segs >= ST_FIRST_SG)
4122 st_max_sg_segs = max_sg_segs;
4123 }
4124
4125 #ifndef MODULE
4126 /* Set the boot options. Syntax is defined in Documenation/scsi/st.txt.
4127 */
st_setup(char * str)4128 static int __init st_setup(char *str)
4129 {
4130 int i, len, ints[5];
4131 char *stp;
4132
4133 stp = get_options(str, ARRAY_SIZE(ints), ints);
4134
4135 if (ints[0] > 0) {
4136 for (i = 0; i < ints[0] && i < ARRAY_SIZE(parms); i++)
4137 if (parms[i].val)
4138 *parms[i].val = ints[i + 1];
4139 } else {
4140 while (stp != NULL) {
4141 for (i = 0; i < ARRAY_SIZE(parms); i++) {
4142 len = strlen(parms[i].name);
4143 if (!strncmp(stp, parms[i].name, len) &&
4144 (*(stp + len) == ':' || *(stp + len) == '=')) {
4145 if (parms[i].val)
4146 *parms[i].val =
4147 simple_strtoul(stp + len + 1, NULL, 0);
4148 else
4149 printk(KERN_WARNING "st: Obsolete parameter %s\n",
4150 parms[i].name);
4151 break;
4152 }
4153 }
4154 if (i >= ARRAY_SIZE(parms))
4155 printk(KERN_WARNING "st: invalid parameter in '%s'\n",
4156 stp);
4157 stp = strchr(stp, ',');
4158 if (stp)
4159 stp++;
4160 }
4161 }
4162
4163 validate_options();
4164
4165 return 1;
4166 }
4167
4168 __setup("st=", st_setup);
4169
4170 #endif
4171
4172 static const struct file_operations st_fops =
4173 {
4174 .owner = THIS_MODULE,
4175 .read = st_read,
4176 .write = st_write,
4177 .unlocked_ioctl = st_ioctl,
4178 #ifdef CONFIG_COMPAT
4179 .compat_ioctl = st_compat_ioctl,
4180 #endif
4181 .open = st_open,
4182 .flush = st_flush,
4183 .release = st_release,
4184 .llseek = noop_llseek,
4185 };
4186
create_one_cdev(struct scsi_tape * tape,int mode,int rew)4187 static int create_one_cdev(struct scsi_tape *tape, int mode, int rew)
4188 {
4189 int i, error;
4190 dev_t cdev_devno;
4191 struct cdev *cdev;
4192 struct device *dev;
4193 struct st_modedef *STm = &(tape->modes[mode]);
4194 char name[10];
4195 int dev_num = tape->index;
4196
4197 cdev_devno = MKDEV(SCSI_TAPE_MAJOR, TAPE_MINOR(dev_num, mode, rew));
4198
4199 cdev = cdev_alloc();
4200 if (!cdev) {
4201 pr_err("st%d: out of memory. Device not attached.\n", dev_num);
4202 error = -ENOMEM;
4203 goto out;
4204 }
4205 cdev->owner = THIS_MODULE;
4206 cdev->ops = &st_fops;
4207 STm->cdevs[rew] = cdev;
4208
4209 error = cdev_add(cdev, cdev_devno, 1);
4210 if (error) {
4211 pr_err("st%d: Can't add %s-rewind mode %d\n", dev_num,
4212 rew ? "non" : "auto", mode);
4213 pr_err("st%d: Device not attached.\n", dev_num);
4214 goto out_free;
4215 }
4216
4217 i = mode << (4 - ST_NBR_MODE_BITS);
4218 snprintf(name, 10, "%s%s%s", rew ? "n" : "",
4219 tape->disk->disk_name, st_formats[i]);
4220
4221 dev = device_create(&st_sysfs_class, &tape->device->sdev_gendev,
4222 cdev_devno, &tape->modes[mode], "%s", name);
4223 if (IS_ERR(dev)) {
4224 pr_err("st%d: device_create failed\n", dev_num);
4225 error = PTR_ERR(dev);
4226 goto out_free;
4227 }
4228
4229 STm->devs[rew] = dev;
4230
4231 return 0;
4232 out_free:
4233 cdev_del(STm->cdevs[rew]);
4234 out:
4235 STm->cdevs[rew] = NULL;
4236 STm->devs[rew] = NULL;
4237 return error;
4238 }
4239
create_cdevs(struct scsi_tape * tape)4240 static int create_cdevs(struct scsi_tape *tape)
4241 {
4242 int mode, error;
4243 for (mode = 0; mode < ST_NBR_MODES; ++mode) {
4244 error = create_one_cdev(tape, mode, 0);
4245 if (error)
4246 return error;
4247 error = create_one_cdev(tape, mode, 1);
4248 if (error)
4249 return error;
4250 }
4251
4252 return sysfs_create_link(&tape->device->sdev_gendev.kobj,
4253 &tape->modes[0].devs[0]->kobj, "tape");
4254 }
4255
remove_cdevs(struct scsi_tape * tape)4256 static void remove_cdevs(struct scsi_tape *tape)
4257 {
4258 int mode, rew;
4259 sysfs_remove_link(&tape->device->sdev_gendev.kobj, "tape");
4260 for (mode = 0; mode < ST_NBR_MODES; mode++) {
4261 struct st_modedef *STm = &(tape->modes[mode]);
4262 for (rew = 0; rew < 2; rew++) {
4263 if (STm->cdevs[rew])
4264 cdev_del(STm->cdevs[rew]);
4265 if (STm->devs[rew])
4266 device_unregister(STm->devs[rew]);
4267 }
4268 }
4269 }
4270
st_probe(struct device * dev)4271 static int st_probe(struct device *dev)
4272 {
4273 struct scsi_device *SDp = to_scsi_device(dev);
4274 struct gendisk *disk = NULL;
4275 struct scsi_tape *tpnt = NULL;
4276 struct st_modedef *STm;
4277 struct st_partstat *STps;
4278 struct st_buffer *buffer;
4279 int i, error;
4280 char *stp;
4281
4282 if (SDp->type != TYPE_TAPE)
4283 return -ENODEV;
4284 if ((stp = st_incompatible(SDp))) {
4285 sdev_printk(KERN_INFO, SDp,
4286 "OnStream tapes are no longer supported;\n");
4287 sdev_printk(KERN_INFO, SDp,
4288 "please mail to linux-scsi@vger.kernel.org.\n");
4289 return -ENODEV;
4290 }
4291
4292 scsi_autopm_get_device(SDp);
4293 i = queue_max_segments(SDp->request_queue);
4294 if (st_max_sg_segs < i)
4295 i = st_max_sg_segs;
4296 buffer = new_tape_buffer(i);
4297 if (buffer == NULL) {
4298 sdev_printk(KERN_ERR, SDp,
4299 "st: Can't allocate new tape buffer. "
4300 "Device not attached.\n");
4301 goto out;
4302 }
4303
4304 disk = alloc_disk(1);
4305 if (!disk) {
4306 sdev_printk(KERN_ERR, SDp,
4307 "st: out of memory. Device not attached.\n");
4308 goto out_buffer_free;
4309 }
4310
4311 tpnt = kzalloc(sizeof(struct scsi_tape), GFP_KERNEL);
4312 if (tpnt == NULL) {
4313 sdev_printk(KERN_ERR, SDp,
4314 "st: Can't allocate device descriptor.\n");
4315 goto out_put_disk;
4316 }
4317 kref_init(&tpnt->kref);
4318 tpnt->disk = disk;
4319 disk->private_data = &tpnt->driver;
4320 /* SCSI tape doesn't register this gendisk via add_disk(). Manually
4321 * take queue reference that release_disk() expects. */
4322 if (!blk_get_queue(SDp->request_queue))
4323 goto out_put_disk;
4324 disk->queue = SDp->request_queue;
4325 tpnt->driver = &st_template;
4326
4327 tpnt->device = SDp;
4328 if (SDp->scsi_level <= 2)
4329 tpnt->tape_type = MT_ISSCSI1;
4330 else
4331 tpnt->tape_type = MT_ISSCSI2;
4332
4333 tpnt->buffer = buffer;
4334 tpnt->buffer->last_SRpnt = NULL;
4335
4336 tpnt->inited = 0;
4337 tpnt->dirty = 0;
4338 tpnt->in_use = 0;
4339 tpnt->drv_buffer = 1; /* Try buffering if no mode sense */
4340 tpnt->use_pf = (SDp->scsi_level >= SCSI_2);
4341 tpnt->density = 0;
4342 tpnt->do_auto_lock = ST_AUTO_LOCK;
4343 tpnt->can_bsr = (SDp->scsi_level > 2 ? 1 : ST_IN_FILE_POS); /* BSR mandatory in SCSI3 */
4344 tpnt->can_partitions = 0;
4345 tpnt->two_fm = ST_TWO_FM;
4346 tpnt->fast_mteom = ST_FAST_MTEOM;
4347 tpnt->scsi2_logical = ST_SCSI2LOGICAL;
4348 tpnt->sili = ST_SILI;
4349 tpnt->immediate = ST_NOWAIT;
4350 tpnt->immediate_filemark = 0;
4351 tpnt->default_drvbuffer = 0xff; /* No forced buffering */
4352 tpnt->partition = 0;
4353 tpnt->new_partition = 0;
4354 tpnt->nbr_partitions = 0;
4355 blk_queue_rq_timeout(tpnt->device->request_queue, ST_TIMEOUT);
4356 tpnt->long_timeout = ST_LONG_TIMEOUT;
4357 tpnt->try_dio = try_direct_io;
4358
4359 for (i = 0; i < ST_NBR_MODES; i++) {
4360 STm = &(tpnt->modes[i]);
4361 STm->defined = 0;
4362 STm->sysv = ST_SYSV;
4363 STm->defaults_for_writes = 0;
4364 STm->do_async_writes = ST_ASYNC_WRITES;
4365 STm->do_buffer_writes = ST_BUFFER_WRITES;
4366 STm->do_read_ahead = ST_READ_AHEAD;
4367 STm->default_compression = ST_DONT_TOUCH;
4368 STm->default_blksize = (-1); /* No forced size */
4369 STm->default_density = (-1); /* No forced density */
4370 STm->tape = tpnt;
4371 }
4372
4373 for (i = 0; i < ST_NBR_PARTITIONS; i++) {
4374 STps = &(tpnt->ps[i]);
4375 STps->rw = ST_IDLE;
4376 STps->eof = ST_NOEOF;
4377 STps->at_sm = 0;
4378 STps->last_block_valid = 0;
4379 STps->drv_block = (-1);
4380 STps->drv_file = (-1);
4381 }
4382
4383 tpnt->current_mode = 0;
4384 tpnt->modes[0].defined = 1;
4385
4386 tpnt->density_changed = tpnt->compression_changed =
4387 tpnt->blksize_changed = 0;
4388 mutex_init(&tpnt->lock);
4389
4390 idr_preload(GFP_KERNEL);
4391 spin_lock(&st_index_lock);
4392 error = idr_alloc(&st_index_idr, tpnt, 0, ST_MAX_TAPES + 1, GFP_NOWAIT);
4393 spin_unlock(&st_index_lock);
4394 idr_preload_end();
4395 if (error < 0) {
4396 pr_warn("st: idr allocation failed: %d\n", error);
4397 goto out_put_queue;
4398 }
4399 tpnt->index = error;
4400 sprintf(disk->disk_name, "st%d", tpnt->index);
4401 tpnt->stats = kzalloc(sizeof(struct scsi_tape_stats), GFP_KERNEL);
4402 if (tpnt->stats == NULL) {
4403 sdev_printk(KERN_ERR, SDp,
4404 "st: Can't allocate statistics.\n");
4405 goto out_idr_remove;
4406 }
4407
4408 dev_set_drvdata(dev, tpnt);
4409
4410
4411 error = create_cdevs(tpnt);
4412 if (error)
4413 goto out_remove_devs;
4414 scsi_autopm_put_device(SDp);
4415
4416 sdev_printk(KERN_NOTICE, SDp,
4417 "Attached scsi tape %s\n", tape_name(tpnt));
4418 sdev_printk(KERN_INFO, SDp, "%s: try direct i/o: %s (alignment %d B)\n",
4419 tape_name(tpnt), tpnt->try_dio ? "yes" : "no",
4420 queue_dma_alignment(SDp->request_queue) + 1);
4421
4422 return 0;
4423
4424 out_remove_devs:
4425 remove_cdevs(tpnt);
4426 kfree(tpnt->stats);
4427 out_idr_remove:
4428 spin_lock(&st_index_lock);
4429 idr_remove(&st_index_idr, tpnt->index);
4430 spin_unlock(&st_index_lock);
4431 out_put_queue:
4432 blk_put_queue(disk->queue);
4433 out_put_disk:
4434 put_disk(disk);
4435 kfree(tpnt);
4436 out_buffer_free:
4437 kfree(buffer);
4438 out:
4439 scsi_autopm_put_device(SDp);
4440 return -ENODEV;
4441 };
4442
4443
st_remove(struct device * dev)4444 static int st_remove(struct device *dev)
4445 {
4446 struct scsi_tape *tpnt = dev_get_drvdata(dev);
4447 int index = tpnt->index;
4448
4449 scsi_autopm_get_device(to_scsi_device(dev));
4450 remove_cdevs(tpnt);
4451
4452 mutex_lock(&st_ref_mutex);
4453 kref_put(&tpnt->kref, scsi_tape_release);
4454 mutex_unlock(&st_ref_mutex);
4455 spin_lock(&st_index_lock);
4456 idr_remove(&st_index_idr, index);
4457 spin_unlock(&st_index_lock);
4458 return 0;
4459 }
4460
4461 /**
4462 * scsi_tape_release - Called to free the Scsi_Tape structure
4463 * @kref: pointer to embedded kref
4464 *
4465 * st_ref_mutex must be held entering this routine. Because it is
4466 * called on last put, you should always use the scsi_tape_get()
4467 * scsi_tape_put() helpers which manipulate the semaphore directly
4468 * and never do a direct kref_put().
4469 **/
scsi_tape_release(struct kref * kref)4470 static void scsi_tape_release(struct kref *kref)
4471 {
4472 struct scsi_tape *tpnt = to_scsi_tape(kref);
4473 struct gendisk *disk = tpnt->disk;
4474
4475 tpnt->device = NULL;
4476
4477 if (tpnt->buffer) {
4478 normalize_buffer(tpnt->buffer);
4479 kfree(tpnt->buffer->reserved_pages);
4480 kfree(tpnt->buffer);
4481 }
4482
4483 disk->private_data = NULL;
4484 put_disk(disk);
4485 kfree(tpnt->stats);
4486 kfree(tpnt);
4487 return;
4488 }
4489
4490 static struct class st_sysfs_class = {
4491 .name = "scsi_tape",
4492 .dev_groups = st_dev_groups,
4493 };
4494
init_st(void)4495 static int __init init_st(void)
4496 {
4497 int err;
4498
4499 validate_options();
4500
4501 printk(KERN_INFO "st: Version %s, fixed bufsize %d, s/g segs %d\n",
4502 verstr, st_fixed_buffer_size, st_max_sg_segs);
4503
4504 debugging = (debug_flag > 0) ? debug_flag : NO_DEBUG;
4505 if (debugging) {
4506 printk(KERN_INFO "st: Debugging enabled debug_flag = %d\n",
4507 debugging);
4508 }
4509
4510 err = class_register(&st_sysfs_class);
4511 if (err) {
4512 pr_err("Unable register sysfs class for SCSI tapes\n");
4513 return err;
4514 }
4515
4516 err = register_chrdev_region(MKDEV(SCSI_TAPE_MAJOR, 0),
4517 ST_MAX_TAPE_ENTRIES, "st");
4518 if (err) {
4519 printk(KERN_ERR "Unable to get major %d for SCSI tapes\n",
4520 SCSI_TAPE_MAJOR);
4521 goto err_class;
4522 }
4523
4524 err = scsi_register_driver(&st_template.gendrv);
4525 if (err)
4526 goto err_chrdev;
4527
4528 return 0;
4529
4530 err_chrdev:
4531 unregister_chrdev_region(MKDEV(SCSI_TAPE_MAJOR, 0),
4532 ST_MAX_TAPE_ENTRIES);
4533 err_class:
4534 class_unregister(&st_sysfs_class);
4535 return err;
4536 }
4537
exit_st(void)4538 static void __exit exit_st(void)
4539 {
4540 scsi_unregister_driver(&st_template.gendrv);
4541 unregister_chrdev_region(MKDEV(SCSI_TAPE_MAJOR, 0),
4542 ST_MAX_TAPE_ENTRIES);
4543 class_unregister(&st_sysfs_class);
4544 idr_destroy(&st_index_idr);
4545 printk(KERN_INFO "st: Unloaded.\n");
4546 }
4547
4548 module_init(init_st);
4549 module_exit(exit_st);
4550
4551
4552 /* The sysfs driver interface. Read-only at the moment */
try_direct_io_show(struct device_driver * ddp,char * buf)4553 static ssize_t try_direct_io_show(struct device_driver *ddp, char *buf)
4554 {
4555 return scnprintf(buf, PAGE_SIZE, "%d\n", try_direct_io);
4556 }
4557 static DRIVER_ATTR_RO(try_direct_io);
4558
fixed_buffer_size_show(struct device_driver * ddp,char * buf)4559 static ssize_t fixed_buffer_size_show(struct device_driver *ddp, char *buf)
4560 {
4561 return scnprintf(buf, PAGE_SIZE, "%d\n", st_fixed_buffer_size);
4562 }
4563 static DRIVER_ATTR_RO(fixed_buffer_size);
4564
max_sg_segs_show(struct device_driver * ddp,char * buf)4565 static ssize_t max_sg_segs_show(struct device_driver *ddp, char *buf)
4566 {
4567 return scnprintf(buf, PAGE_SIZE, "%d\n", st_max_sg_segs);
4568 }
4569 static DRIVER_ATTR_RO(max_sg_segs);
4570
version_show(struct device_driver * ddd,char * buf)4571 static ssize_t version_show(struct device_driver *ddd, char *buf)
4572 {
4573 return scnprintf(buf, PAGE_SIZE, "[%s]\n", verstr);
4574 }
4575 static DRIVER_ATTR_RO(version);
4576
4577 #if DEBUG
debug_flag_store(struct device_driver * ddp,const char * buf,size_t count)4578 static ssize_t debug_flag_store(struct device_driver *ddp,
4579 const char *buf, size_t count)
4580 {
4581 /* We only care what the first byte of the data is the rest is unused.
4582 * if it's a '1' we turn on debug and if it's a '0' we disable it. All
4583 * other values have -EINVAL returned if they are passed in.
4584 */
4585 if (count > 0) {
4586 if (buf[0] == '0') {
4587 debugging = NO_DEBUG;
4588 return count;
4589 } else if (buf[0] == '1') {
4590 debugging = 1;
4591 return count;
4592 }
4593 }
4594 return -EINVAL;
4595 }
4596
debug_flag_show(struct device_driver * ddp,char * buf)4597 static ssize_t debug_flag_show(struct device_driver *ddp, char *buf)
4598 {
4599 return scnprintf(buf, PAGE_SIZE, "%d\n", debugging);
4600 }
4601 static DRIVER_ATTR_RW(debug_flag);
4602 #endif
4603
4604 static struct attribute *st_drv_attrs[] = {
4605 &driver_attr_try_direct_io.attr,
4606 &driver_attr_fixed_buffer_size.attr,
4607 &driver_attr_max_sg_segs.attr,
4608 &driver_attr_version.attr,
4609 #if DEBUG
4610 &driver_attr_debug_flag.attr,
4611 #endif
4612 NULL,
4613 };
4614 ATTRIBUTE_GROUPS(st_drv);
4615
4616 /* The sysfs simple class interface */
4617 static ssize_t
defined_show(struct device * dev,struct device_attribute * attr,char * buf)4618 defined_show(struct device *dev, struct device_attribute *attr, char *buf)
4619 {
4620 struct st_modedef *STm = dev_get_drvdata(dev);
4621 ssize_t l = 0;
4622
4623 l = snprintf(buf, PAGE_SIZE, "%d\n", STm->defined);
4624 return l;
4625 }
4626 static DEVICE_ATTR_RO(defined);
4627
4628 static ssize_t
default_blksize_show(struct device * dev,struct device_attribute * attr,char * buf)4629 default_blksize_show(struct device *dev, struct device_attribute *attr,
4630 char *buf)
4631 {
4632 struct st_modedef *STm = dev_get_drvdata(dev);
4633 ssize_t l = 0;
4634
4635 l = snprintf(buf, PAGE_SIZE, "%d\n", STm->default_blksize);
4636 return l;
4637 }
4638 static DEVICE_ATTR_RO(default_blksize);
4639
4640 static ssize_t
default_density_show(struct device * dev,struct device_attribute * attr,char * buf)4641 default_density_show(struct device *dev, struct device_attribute *attr,
4642 char *buf)
4643 {
4644 struct st_modedef *STm = dev_get_drvdata(dev);
4645 ssize_t l = 0;
4646 char *fmt;
4647
4648 fmt = STm->default_density >= 0 ? "0x%02x\n" : "%d\n";
4649 l = snprintf(buf, PAGE_SIZE, fmt, STm->default_density);
4650 return l;
4651 }
4652 static DEVICE_ATTR_RO(default_density);
4653
4654 static ssize_t
default_compression_show(struct device * dev,struct device_attribute * attr,char * buf)4655 default_compression_show(struct device *dev, struct device_attribute *attr,
4656 char *buf)
4657 {
4658 struct st_modedef *STm = dev_get_drvdata(dev);
4659 ssize_t l = 0;
4660
4661 l = snprintf(buf, PAGE_SIZE, "%d\n", STm->default_compression - 1);
4662 return l;
4663 }
4664 static DEVICE_ATTR_RO(default_compression);
4665
4666 static ssize_t
options_show(struct device * dev,struct device_attribute * attr,char * buf)4667 options_show(struct device *dev, struct device_attribute *attr, char *buf)
4668 {
4669 struct st_modedef *STm = dev_get_drvdata(dev);
4670 struct scsi_tape *STp = STm->tape;
4671 int options;
4672 ssize_t l = 0;
4673
4674 options = STm->do_buffer_writes ? MT_ST_BUFFER_WRITES : 0;
4675 options |= STm->do_async_writes ? MT_ST_ASYNC_WRITES : 0;
4676 options |= STm->do_read_ahead ? MT_ST_READ_AHEAD : 0;
4677 DEB( options |= debugging ? MT_ST_DEBUGGING : 0 );
4678 options |= STp->two_fm ? MT_ST_TWO_FM : 0;
4679 options |= STp->fast_mteom ? MT_ST_FAST_MTEOM : 0;
4680 options |= STm->defaults_for_writes ? MT_ST_DEF_WRITES : 0;
4681 options |= STp->can_bsr ? MT_ST_CAN_BSR : 0;
4682 options |= STp->omit_blklims ? MT_ST_NO_BLKLIMS : 0;
4683 options |= STp->can_partitions ? MT_ST_CAN_PARTITIONS : 0;
4684 options |= STp->scsi2_logical ? MT_ST_SCSI2LOGICAL : 0;
4685 options |= STm->sysv ? MT_ST_SYSV : 0;
4686 options |= STp->immediate ? MT_ST_NOWAIT : 0;
4687 options |= STp->immediate_filemark ? MT_ST_NOWAIT_EOF : 0;
4688 options |= STp->sili ? MT_ST_SILI : 0;
4689
4690 l = snprintf(buf, PAGE_SIZE, "0x%08x\n", options);
4691 return l;
4692 }
4693 static DEVICE_ATTR_RO(options);
4694
4695 /* Support for tape stats */
4696
4697 /**
4698 * read_cnt_show - return read count - count of reads made from tape drive
4699 * @dev: struct device
4700 * @attr: attribute structure
4701 * @buf: buffer to return formatted data in
4702 */
read_cnt_show(struct device * dev,struct device_attribute * attr,char * buf)4703 static ssize_t read_cnt_show(struct device *dev,
4704 struct device_attribute *attr, char *buf)
4705 {
4706 struct st_modedef *STm = dev_get_drvdata(dev);
4707
4708 return sprintf(buf, "%lld",
4709 (long long)atomic64_read(&STm->tape->stats->read_cnt));
4710 }
4711 static DEVICE_ATTR_RO(read_cnt);
4712
4713 /**
4714 * read_byte_cnt_show - return read byte count - tape drives
4715 * may use blocks less than 512 bytes this gives the raw byte count of
4716 * of data read from the tape drive.
4717 * @dev: struct device
4718 * @attr: attribute structure
4719 * @buf: buffer to return formatted data in
4720 */
read_byte_cnt_show(struct device * dev,struct device_attribute * attr,char * buf)4721 static ssize_t read_byte_cnt_show(struct device *dev,
4722 struct device_attribute *attr, char *buf)
4723 {
4724 struct st_modedef *STm = dev_get_drvdata(dev);
4725
4726 return sprintf(buf, "%lld",
4727 (long long)atomic64_read(&STm->tape->stats->read_byte_cnt));
4728 }
4729 static DEVICE_ATTR_RO(read_byte_cnt);
4730
4731 /**
4732 * read_ns_show - return read ns - overall time spent waiting on reads in ns.
4733 * @dev: struct device
4734 * @attr: attribute structure
4735 * @buf: buffer to return formatted data in
4736 */
read_ns_show(struct device * dev,struct device_attribute * attr,char * buf)4737 static ssize_t read_ns_show(struct device *dev,
4738 struct device_attribute *attr, char *buf)
4739 {
4740 struct st_modedef *STm = dev_get_drvdata(dev);
4741
4742 return sprintf(buf, "%lld",
4743 (long long)atomic64_read(&STm->tape->stats->tot_read_time));
4744 }
4745 static DEVICE_ATTR_RO(read_ns);
4746
4747 /**
4748 * write_cnt_show - write count - number of user calls
4749 * to write(2) that have written data to tape.
4750 * @dev: struct device
4751 * @attr: attribute structure
4752 * @buf: buffer to return formatted data in
4753 */
write_cnt_show(struct device * dev,struct device_attribute * attr,char * buf)4754 static ssize_t write_cnt_show(struct device *dev,
4755 struct device_attribute *attr, char *buf)
4756 {
4757 struct st_modedef *STm = dev_get_drvdata(dev);
4758
4759 return sprintf(buf, "%lld",
4760 (long long)atomic64_read(&STm->tape->stats->write_cnt));
4761 }
4762 static DEVICE_ATTR_RO(write_cnt);
4763
4764 /**
4765 * write_byte_cnt_show - write byte count - raw count of
4766 * bytes written to tape.
4767 * @dev: struct device
4768 * @attr: attribute structure
4769 * @buf: buffer to return formatted data in
4770 */
write_byte_cnt_show(struct device * dev,struct device_attribute * attr,char * buf)4771 static ssize_t write_byte_cnt_show(struct device *dev,
4772 struct device_attribute *attr, char *buf)
4773 {
4774 struct st_modedef *STm = dev_get_drvdata(dev);
4775
4776 return sprintf(buf, "%lld",
4777 (long long)atomic64_read(&STm->tape->stats->write_byte_cnt));
4778 }
4779 static DEVICE_ATTR_RO(write_byte_cnt);
4780
4781 /**
4782 * write_ns_show - write ns - number of nanoseconds waiting on write
4783 * requests to complete.
4784 * @dev: struct device
4785 * @attr: attribute structure
4786 * @buf: buffer to return formatted data in
4787 */
write_ns_show(struct device * dev,struct device_attribute * attr,char * buf)4788 static ssize_t write_ns_show(struct device *dev,
4789 struct device_attribute *attr, char *buf)
4790 {
4791 struct st_modedef *STm = dev_get_drvdata(dev);
4792
4793 return sprintf(buf, "%lld",
4794 (long long)atomic64_read(&STm->tape->stats->tot_write_time));
4795 }
4796 static DEVICE_ATTR_RO(write_ns);
4797
4798 /**
4799 * in_flight_show - number of I/Os currently in flight -
4800 * in most cases this will be either 0 or 1. It may be higher if someone
4801 * has also issued other SCSI commands such as via an ioctl.
4802 * @dev: struct device
4803 * @attr: attribute structure
4804 * @buf: buffer to return formatted data in
4805 */
in_flight_show(struct device * dev,struct device_attribute * attr,char * buf)4806 static ssize_t in_flight_show(struct device *dev,
4807 struct device_attribute *attr, char *buf)
4808 {
4809 struct st_modedef *STm = dev_get_drvdata(dev);
4810
4811 return sprintf(buf, "%lld",
4812 (long long)atomic64_read(&STm->tape->stats->in_flight));
4813 }
4814 static DEVICE_ATTR_RO(in_flight);
4815
4816 /**
4817 * io_ns_show - io wait ns - this is the number of ns spent
4818 * waiting on all I/O to complete. This includes tape movement commands
4819 * such as rewinding, seeking to end of file or tape, it also includes
4820 * read and write. To determine the time spent on tape movement
4821 * subtract the read and write ns from this value.
4822 * @dev: struct device
4823 * @attr: attribute structure
4824 * @buf: buffer to return formatted data in
4825 */
io_ns_show(struct device * dev,struct device_attribute * attr,char * buf)4826 static ssize_t io_ns_show(struct device *dev,
4827 struct device_attribute *attr, char *buf)
4828 {
4829 struct st_modedef *STm = dev_get_drvdata(dev);
4830
4831 return sprintf(buf, "%lld",
4832 (long long)atomic64_read(&STm->tape->stats->tot_io_time));
4833 }
4834 static DEVICE_ATTR_RO(io_ns);
4835
4836 /**
4837 * other_cnt_show - other io count - this is the number of
4838 * I/O requests other than read and write requests.
4839 * Typically these are tape movement requests but will include driver
4840 * tape movement. This includes only requests issued by the st driver.
4841 * @dev: struct device
4842 * @attr: attribute structure
4843 * @buf: buffer to return formatted data in
4844 */
other_cnt_show(struct device * dev,struct device_attribute * attr,char * buf)4845 static ssize_t other_cnt_show(struct device *dev,
4846 struct device_attribute *attr, char *buf)
4847 {
4848 struct st_modedef *STm = dev_get_drvdata(dev);
4849
4850 return sprintf(buf, "%lld",
4851 (long long)atomic64_read(&STm->tape->stats->other_cnt));
4852 }
4853 static DEVICE_ATTR_RO(other_cnt);
4854
4855 /**
4856 * resid_cnt_show - A count of the number of times we get a residual
4857 * count - this should indicate someone issuing reads larger than the
4858 * block size on tape.
4859 * @dev: struct device
4860 * @attr: attribute structure
4861 * @buf: buffer to return formatted data in
4862 */
resid_cnt_show(struct device * dev,struct device_attribute * attr,char * buf)4863 static ssize_t resid_cnt_show(struct device *dev,
4864 struct device_attribute *attr, char *buf)
4865 {
4866 struct st_modedef *STm = dev_get_drvdata(dev);
4867
4868 return sprintf(buf, "%lld",
4869 (long long)atomic64_read(&STm->tape->stats->resid_cnt));
4870 }
4871 static DEVICE_ATTR_RO(resid_cnt);
4872
4873 static struct attribute *st_dev_attrs[] = {
4874 &dev_attr_defined.attr,
4875 &dev_attr_default_blksize.attr,
4876 &dev_attr_default_density.attr,
4877 &dev_attr_default_compression.attr,
4878 &dev_attr_options.attr,
4879 NULL,
4880 };
4881
4882 static struct attribute *st_stats_attrs[] = {
4883 &dev_attr_read_cnt.attr,
4884 &dev_attr_read_byte_cnt.attr,
4885 &dev_attr_read_ns.attr,
4886 &dev_attr_write_cnt.attr,
4887 &dev_attr_write_byte_cnt.attr,
4888 &dev_attr_write_ns.attr,
4889 &dev_attr_in_flight.attr,
4890 &dev_attr_io_ns.attr,
4891 &dev_attr_other_cnt.attr,
4892 &dev_attr_resid_cnt.attr,
4893 NULL,
4894 };
4895
4896 static struct attribute_group stats_group = {
4897 .name = "stats",
4898 .attrs = st_stats_attrs,
4899 };
4900
4901 static struct attribute_group st_group = {
4902 .attrs = st_dev_attrs,
4903 };
4904
4905 static const struct attribute_group *st_dev_groups[] = {
4906 &st_group,
4907 &stats_group,
4908 NULL,
4909 };
4910
4911 /* 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)4912 static int sgl_map_user_pages(struct st_buffer *STbp,
4913 const unsigned int max_pages, unsigned long uaddr,
4914 size_t count, int rw)
4915 {
4916 unsigned long end = (uaddr + count + PAGE_SIZE - 1) >> PAGE_SHIFT;
4917 unsigned long start = uaddr >> PAGE_SHIFT;
4918 const int nr_pages = end - start;
4919 int res, i;
4920 struct page **pages;
4921 struct rq_map_data *mdata = &STbp->map_data;
4922
4923 /* User attempted Overflow! */
4924 if ((uaddr + count) < uaddr)
4925 return -EINVAL;
4926
4927 /* Too big */
4928 if (nr_pages > max_pages)
4929 return -ENOMEM;
4930
4931 /* Hmm? */
4932 if (count == 0)
4933 return 0;
4934
4935 pages = kmalloc_array(max_pages, sizeof(*pages), GFP_KERNEL);
4936 if (pages == NULL)
4937 return -ENOMEM;
4938
4939 /* Try to fault in all of the necessary pages */
4940 /* rw==READ means read from drive, write into memory area */
4941 res = pin_user_pages_fast(uaddr, nr_pages, rw == READ ? FOLL_WRITE : 0,
4942 pages);
4943
4944 /* Errors and no page mapped should return here */
4945 if (res < nr_pages)
4946 goto out_unmap;
4947
4948 for (i=0; i < nr_pages; i++) {
4949 /* FIXME: flush superflous for rw==READ,
4950 * probably wrong function for rw==WRITE
4951 */
4952 flush_dcache_page(pages[i]);
4953 }
4954
4955 mdata->offset = uaddr & ~PAGE_MASK;
4956 STbp->mapped_pages = pages;
4957
4958 return nr_pages;
4959 out_unmap:
4960 if (res > 0) {
4961 unpin_user_pages(pages, res);
4962 res = 0;
4963 }
4964 kfree(pages);
4965 return res;
4966 }
4967
4968
4969 /* And unmap them... */
sgl_unmap_user_pages(struct st_buffer * STbp,const unsigned int nr_pages,int dirtied)4970 static int sgl_unmap_user_pages(struct st_buffer *STbp,
4971 const unsigned int nr_pages, int dirtied)
4972 {
4973 /* FIXME: cache flush missing for rw==READ */
4974 unpin_user_pages_dirty_lock(STbp->mapped_pages, nr_pages, dirtied);
4975
4976 kfree(STbp->mapped_pages);
4977 STbp->mapped_pages = NULL;
4978
4979 return 0;
4980 }
4981