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, 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(req->q, 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, STp->restr_dma)) {
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, STp->restr_dma)) {
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 break;
2850 case MTRETEN:
2851 cmd[0] = START_STOP;
2852 if (STp->immediate) {
2853 cmd[1] = 1; /* Don't wait for completion */
2854 timeout = STp->device->request_queue->rq_timeout;
2855 }
2856 cmd[4] = 3;
2857 DEBC_printk(STp, "Retensioning tape.\n");
2858 fileno = blkno = at_sm = 0;
2859 break;
2860 case MTEOM:
2861 if (!STp->fast_mteom) {
2862 /* space to the end of tape */
2863 ioctl_result = st_int_ioctl(STp, MTFSF, 0x7fffff);
2864 fileno = STps->drv_file;
2865 if (STps->eof >= ST_EOD_1)
2866 return 0;
2867 /* The next lines would hide the number of spaced FileMarks
2868 That's why I inserted the previous lines. I had no luck
2869 with detecting EOM with FSF, so we go now to EOM.
2870 Joerg Weule */
2871 } else
2872 fileno = (-1);
2873 cmd[0] = SPACE;
2874 cmd[1] = 3;
2875 DEBC_printk(STp, "Spacing to end of recorded medium.\n");
2876 blkno = -1;
2877 at_sm = 0;
2878 break;
2879 case MTERASE:
2880 if (STp->write_prot)
2881 return (-EACCES);
2882 cmd[0] = ERASE;
2883 cmd[1] = (arg ? 1 : 0); /* Long erase with non-zero argument */
2884 if (STp->immediate) {
2885 cmd[1] |= 2; /* Don't wait for completion */
2886 timeout = STp->device->request_queue->rq_timeout;
2887 }
2888 else
2889 timeout = STp->long_timeout * 8;
2890
2891 DEBC_printk(STp, "Erasing tape.\n");
2892 fileno = blkno = at_sm = 0;
2893 break;
2894 case MTSETBLK: /* Set block length */
2895 case MTSETDENSITY: /* Set tape density */
2896 case MTSETDRVBUFFER: /* Set drive buffering */
2897 case SET_DENS_AND_BLK: /* Set density and block size */
2898 chg_eof = 0;
2899 if (STp->dirty || (STp->buffer)->buffer_bytes != 0)
2900 return (-EIO); /* Not allowed if data in buffer */
2901 if ((cmd_in == MTSETBLK || cmd_in == SET_DENS_AND_BLK) &&
2902 (arg & MT_ST_BLKSIZE_MASK) != 0 &&
2903 STp->max_block > 0 &&
2904 ((arg & MT_ST_BLKSIZE_MASK) < STp->min_block ||
2905 (arg & MT_ST_BLKSIZE_MASK) > STp->max_block)) {
2906 st_printk(KERN_WARNING, STp, "Illegal block size.\n");
2907 return (-EINVAL);
2908 }
2909 cmd[0] = MODE_SELECT;
2910 if ((STp->use_pf & USE_PF))
2911 cmd[1] = MODE_SELECT_PAGE_FORMAT;
2912 cmd[4] = datalen = 12;
2913 direction = DMA_TO_DEVICE;
2914
2915 memset((STp->buffer)->b_data, 0, 12);
2916 if (cmd_in == MTSETDRVBUFFER)
2917 (STp->buffer)->b_data[2] = (arg & 7) << 4;
2918 else
2919 (STp->buffer)->b_data[2] =
2920 STp->drv_buffer << 4;
2921 (STp->buffer)->b_data[3] = 8; /* block descriptor length */
2922 if (cmd_in == MTSETDENSITY) {
2923 (STp->buffer)->b_data[4] = arg;
2924 STp->density_changed = 1; /* At least we tried ;-) */
2925 } else if (cmd_in == SET_DENS_AND_BLK)
2926 (STp->buffer)->b_data[4] = arg >> 24;
2927 else
2928 (STp->buffer)->b_data[4] = STp->density;
2929 if (cmd_in == MTSETBLK || cmd_in == SET_DENS_AND_BLK) {
2930 ltmp = arg & MT_ST_BLKSIZE_MASK;
2931 if (cmd_in == MTSETBLK)
2932 STp->blksize_changed = 1; /* At least we tried ;-) */
2933 } else
2934 ltmp = STp->block_size;
2935 (STp->buffer)->b_data[9] = (ltmp >> 16);
2936 (STp->buffer)->b_data[10] = (ltmp >> 8);
2937 (STp->buffer)->b_data[11] = ltmp;
2938 timeout = STp->device->request_queue->rq_timeout;
2939 DEBC(
2940 if (cmd_in == MTSETBLK || cmd_in == SET_DENS_AND_BLK)
2941 st_printk(ST_DEB_MSG, STp,
2942 "Setting block size to %d bytes.\n",
2943 (STp->buffer)->b_data[9] * 65536 +
2944 (STp->buffer)->b_data[10] * 256 +
2945 (STp->buffer)->b_data[11]);
2946 if (cmd_in == MTSETDENSITY || cmd_in == SET_DENS_AND_BLK)
2947 st_printk(ST_DEB_MSG, STp,
2948 "Setting density code to %x.\n",
2949 (STp->buffer)->b_data[4]);
2950 if (cmd_in == MTSETDRVBUFFER)
2951 st_printk(ST_DEB_MSG, STp,
2952 "Setting drive buffer code to %d.\n",
2953 ((STp->buffer)->b_data[2] >> 4) & 7);
2954 )
2955 break;
2956 default:
2957 return (-ENOSYS);
2958 }
2959
2960 SRpnt = st_do_scsi(NULL, STp, cmd, datalen, direction,
2961 timeout, MAX_RETRIES, 1);
2962 if (!SRpnt)
2963 return (STp->buffer)->syscall_result;
2964
2965 ioctl_result = (STp->buffer)->syscall_result;
2966
2967 if (!ioctl_result) { /* SCSI command successful */
2968 st_release_request(SRpnt);
2969 SRpnt = NULL;
2970 STps->drv_block = blkno;
2971 STps->drv_file = fileno;
2972 STps->at_sm = at_sm;
2973
2974 if (cmd_in == MTBSFM)
2975 ioctl_result = st_int_ioctl(STp, MTFSF, 1);
2976 else if (cmd_in == MTFSFM)
2977 ioctl_result = st_int_ioctl(STp, MTBSF, 1);
2978
2979 if (cmd_in == MTSETBLK || cmd_in == SET_DENS_AND_BLK) {
2980 STp->block_size = arg & MT_ST_BLKSIZE_MASK;
2981 if (STp->block_size != 0) {
2982 (STp->buffer)->buffer_blocks =
2983 (STp->buffer)->buffer_size / STp->block_size;
2984 }
2985 (STp->buffer)->buffer_bytes = (STp->buffer)->read_pointer = 0;
2986 if (cmd_in == SET_DENS_AND_BLK)
2987 STp->density = arg >> MT_ST_DENSITY_SHIFT;
2988 } else if (cmd_in == MTSETDRVBUFFER)
2989 STp->drv_buffer = (arg & 7);
2990 else if (cmd_in == MTSETDENSITY)
2991 STp->density = arg;
2992
2993 if (cmd_in == MTEOM)
2994 STps->eof = ST_EOD;
2995 else if (cmd_in == MTFSF)
2996 STps->eof = ST_FM;
2997 else if (chg_eof)
2998 STps->eof = ST_NOEOF;
2999
3000 if (cmd_in == MTWEOF || cmd_in == MTWEOFI)
3001 STps->rw = ST_IDLE; /* prevent automatic WEOF at close */
3002 } else { /* SCSI command was not completely successful. Don't return
3003 from this block without releasing the SCSI command block! */
3004 struct st_cmdstatus *cmdstatp = &STp->buffer->cmdstat;
3005
3006 if (cmdstatp->flags & SENSE_EOM) {
3007 if (cmd_in != MTBSF && cmd_in != MTBSFM &&
3008 cmd_in != MTBSR && cmd_in != MTBSS)
3009 STps->eof = ST_EOM_OK;
3010 STps->drv_block = 0;
3011 }
3012
3013 if (cmdstatp->remainder_valid)
3014 undone = (int)cmdstatp->uremainder64;
3015 else
3016 undone = 0;
3017
3018 if ((cmd_in == MTWEOF || cmd_in == MTWEOFI) &&
3019 cmdstatp->have_sense &&
3020 (cmdstatp->flags & SENSE_EOM)) {
3021 if (cmdstatp->sense_hdr.sense_key == NO_SENSE ||
3022 cmdstatp->sense_hdr.sense_key == RECOVERED_ERROR) {
3023 ioctl_result = 0; /* EOF(s) written successfully at EOM */
3024 STps->eof = ST_NOEOF;
3025 } else { /* Writing EOF(s) failed */
3026 if (fileno >= 0)
3027 fileno -= undone;
3028 if (undone < arg)
3029 STps->eof = ST_NOEOF;
3030 }
3031 STps->drv_file = fileno;
3032 } else if ((cmd_in == MTFSF) || (cmd_in == MTFSFM)) {
3033 if (fileno >= 0)
3034 STps->drv_file = fileno - undone;
3035 else
3036 STps->drv_file = fileno;
3037 STps->drv_block = -1;
3038 STps->eof = ST_NOEOF;
3039 } else if ((cmd_in == MTBSF) || (cmd_in == MTBSFM)) {
3040 if (arg > 0 && undone < 0) /* Some drives get this wrong */
3041 undone = (-undone);
3042 if (STps->drv_file >= 0)
3043 STps->drv_file = fileno + undone;
3044 STps->drv_block = 0;
3045 STps->eof = ST_NOEOF;
3046 } else if (cmd_in == MTFSR) {
3047 if (cmdstatp->flags & SENSE_FMK) { /* Hit filemark */
3048 if (STps->drv_file >= 0)
3049 STps->drv_file++;
3050 STps->drv_block = 0;
3051 STps->eof = ST_FM;
3052 } else {
3053 if (blkno >= undone)
3054 STps->drv_block = blkno - undone;
3055 else
3056 STps->drv_block = (-1);
3057 STps->eof = ST_NOEOF;
3058 }
3059 } else if (cmd_in == MTBSR) {
3060 if (cmdstatp->flags & SENSE_FMK) { /* Hit filemark */
3061 STps->drv_file--;
3062 STps->drv_block = (-1);
3063 } else {
3064 if (arg > 0 && undone < 0) /* Some drives get this wrong */
3065 undone = (-undone);
3066 if (STps->drv_block >= 0)
3067 STps->drv_block = blkno + undone;
3068 }
3069 STps->eof = ST_NOEOF;
3070 } else if (cmd_in == MTEOM) {
3071 STps->drv_file = (-1);
3072 STps->drv_block = (-1);
3073 STps->eof = ST_EOD;
3074 } else if (cmd_in == MTSETBLK ||
3075 cmd_in == MTSETDENSITY ||
3076 cmd_in == MTSETDRVBUFFER ||
3077 cmd_in == SET_DENS_AND_BLK) {
3078 if (cmdstatp->sense_hdr.sense_key == ILLEGAL_REQUEST &&
3079 !(STp->use_pf & PF_TESTED)) {
3080 /* Try the other possible state of Page Format if not
3081 already tried */
3082 STp->use_pf = (STp->use_pf ^ USE_PF) | PF_TESTED;
3083 st_release_request(SRpnt);
3084 SRpnt = NULL;
3085 return st_int_ioctl(STp, cmd_in, arg);
3086 }
3087 } else if (chg_eof)
3088 STps->eof = ST_NOEOF;
3089
3090 if (cmdstatp->sense_hdr.sense_key == BLANK_CHECK)
3091 STps->eof = ST_EOD;
3092
3093 st_release_request(SRpnt);
3094 SRpnt = NULL;
3095 }
3096
3097 return ioctl_result;
3098 }
3099
3100
3101 /* Get the tape position. If bt == 2, arg points into a kernel space mt_loc
3102 structure. */
3103
get_location(struct scsi_tape * STp,unsigned int * block,int * partition,int logical)3104 static int get_location(struct scsi_tape *STp, unsigned int *block, int *partition,
3105 int logical)
3106 {
3107 int result;
3108 unsigned char scmd[MAX_COMMAND_SIZE];
3109 struct st_request *SRpnt;
3110
3111 if (STp->ready != ST_READY)
3112 return (-EIO);
3113
3114 memset(scmd, 0, MAX_COMMAND_SIZE);
3115 if ((STp->device)->scsi_level < SCSI_2) {
3116 scmd[0] = QFA_REQUEST_BLOCK;
3117 scmd[4] = 3;
3118 } else {
3119 scmd[0] = READ_POSITION;
3120 if (!logical && !STp->scsi2_logical)
3121 scmd[1] = 1;
3122 }
3123 SRpnt = st_do_scsi(NULL, STp, scmd, 20, DMA_FROM_DEVICE,
3124 STp->device->request_queue->rq_timeout,
3125 MAX_READY_RETRIES, 1);
3126 if (!SRpnt)
3127 return (STp->buffer)->syscall_result;
3128
3129 if ((STp->buffer)->syscall_result != 0 ||
3130 (STp->device->scsi_level >= SCSI_2 &&
3131 ((STp->buffer)->b_data[0] & 4) != 0)) {
3132 *block = *partition = 0;
3133 DEBC_printk(STp, " Can't read tape position.\n");
3134 result = (-EIO);
3135 } else {
3136 result = 0;
3137 if ((STp->device)->scsi_level < SCSI_2) {
3138 *block = ((STp->buffer)->b_data[0] << 16)
3139 + ((STp->buffer)->b_data[1] << 8)
3140 + (STp->buffer)->b_data[2];
3141 *partition = 0;
3142 } else {
3143 *block = ((STp->buffer)->b_data[4] << 24)
3144 + ((STp->buffer)->b_data[5] << 16)
3145 + ((STp->buffer)->b_data[6] << 8)
3146 + (STp->buffer)->b_data[7];
3147 *partition = (STp->buffer)->b_data[1];
3148 if (((STp->buffer)->b_data[0] & 0x80) &&
3149 (STp->buffer)->b_data[1] == 0) /* BOP of partition 0 */
3150 STp->ps[0].drv_block = STp->ps[0].drv_file = 0;
3151 }
3152 DEBC_printk(STp, "Got tape pos. blk %d part %d.\n",
3153 *block, *partition);
3154 }
3155 st_release_request(SRpnt);
3156 SRpnt = NULL;
3157
3158 return result;
3159 }
3160
3161
3162 /* Set the tape block and partition. Negative partition means that only the
3163 block should be set in vendor specific way. */
set_location(struct scsi_tape * STp,unsigned int block,int partition,int logical)3164 static int set_location(struct scsi_tape *STp, unsigned int block, int partition,
3165 int logical)
3166 {
3167 struct st_partstat *STps;
3168 int result, p;
3169 unsigned int blk;
3170 int timeout;
3171 unsigned char scmd[MAX_COMMAND_SIZE];
3172 struct st_request *SRpnt;
3173
3174 if (STp->ready != ST_READY)
3175 return (-EIO);
3176 timeout = STp->long_timeout;
3177 STps = &(STp->ps[STp->partition]);
3178
3179 DEBC_printk(STp, "Setting block to %d and partition to %d.\n",
3180 block, partition);
3181 DEB(if (partition < 0)
3182 return (-EIO); )
3183
3184 /* Update the location at the partition we are leaving */
3185 if ((!STp->can_partitions && partition != 0) ||
3186 partition >= ST_NBR_PARTITIONS)
3187 return (-EINVAL);
3188 if (partition != STp->partition) {
3189 if (get_location(STp, &blk, &p, 1))
3190 STps->last_block_valid = 0;
3191 else {
3192 STps->last_block_valid = 1;
3193 STps->last_block_visited = blk;
3194 DEBC_printk(STp, "Visited block %d for "
3195 "partition %d saved.\n",
3196 blk, STp->partition);
3197 }
3198 }
3199
3200 memset(scmd, 0, MAX_COMMAND_SIZE);
3201 if ((STp->device)->scsi_level < SCSI_2) {
3202 scmd[0] = QFA_SEEK_BLOCK;
3203 scmd[2] = (block >> 16);
3204 scmd[3] = (block >> 8);
3205 scmd[4] = block;
3206 scmd[5] = 0;
3207 } else {
3208 scmd[0] = SEEK_10;
3209 scmd[3] = (block >> 24);
3210 scmd[4] = (block >> 16);
3211 scmd[5] = (block >> 8);
3212 scmd[6] = block;
3213 if (!logical && !STp->scsi2_logical)
3214 scmd[1] = 4;
3215 if (STp->partition != partition) {
3216 scmd[1] |= 2;
3217 scmd[8] = partition;
3218 DEBC_printk(STp, "Trying to change partition "
3219 "from %d to %d\n", STp->partition,
3220 partition);
3221 }
3222 }
3223 if (STp->immediate) {
3224 scmd[1] |= 1; /* Don't wait for completion */
3225 timeout = STp->device->request_queue->rq_timeout;
3226 }
3227
3228 SRpnt = st_do_scsi(NULL, STp, scmd, 0, DMA_NONE,
3229 timeout, MAX_READY_RETRIES, 1);
3230 if (!SRpnt)
3231 return (STp->buffer)->syscall_result;
3232
3233 STps->drv_block = STps->drv_file = (-1);
3234 STps->eof = ST_NOEOF;
3235 if ((STp->buffer)->syscall_result != 0) {
3236 result = (-EIO);
3237 if (STp->can_partitions &&
3238 (STp->device)->scsi_level >= SCSI_2 &&
3239 (p = find_partition(STp)) >= 0)
3240 STp->partition = p;
3241 } else {
3242 if (STp->can_partitions) {
3243 STp->partition = partition;
3244 STps = &(STp->ps[partition]);
3245 if (!STps->last_block_valid ||
3246 STps->last_block_visited != block) {
3247 STps->at_sm = 0;
3248 STps->rw = ST_IDLE;
3249 }
3250 } else
3251 STps->at_sm = 0;
3252 if (block == 0)
3253 STps->drv_block = STps->drv_file = 0;
3254 result = 0;
3255 }
3256
3257 st_release_request(SRpnt);
3258 SRpnt = NULL;
3259
3260 return result;
3261 }
3262
3263
3264 /* Find the current partition number for the drive status. Called from open and
3265 returns either partition number of negative error code. */
find_partition(struct scsi_tape * STp)3266 static int find_partition(struct scsi_tape *STp)
3267 {
3268 int i, partition;
3269 unsigned int block;
3270
3271 if ((i = get_location(STp, &block, &partition, 1)) < 0)
3272 return i;
3273 if (partition >= ST_NBR_PARTITIONS)
3274 return (-EIO);
3275 return partition;
3276 }
3277
3278
3279 /* Change the partition if necessary */
switch_partition(struct scsi_tape * STp)3280 static int switch_partition(struct scsi_tape *STp)
3281 {
3282 struct st_partstat *STps;
3283
3284 if (STp->partition == STp->new_partition)
3285 return 0;
3286 STps = &(STp->ps[STp->new_partition]);
3287 if (!STps->last_block_valid)
3288 STps->last_block_visited = 0;
3289 return set_location(STp, STps->last_block_visited, STp->new_partition, 1);
3290 }
3291
3292 /* Functions for reading and writing the medium partition mode page. */
3293
3294 #define PART_PAGE 0x11
3295 #define PART_PAGE_FIXED_LENGTH 8
3296
3297 #define PP_OFF_MAX_ADD_PARTS 2
3298 #define PP_OFF_NBR_ADD_PARTS 3
3299 #define PP_OFF_FLAGS 4
3300 #define PP_OFF_PART_UNITS 6
3301 #define PP_OFF_RESERVED 7
3302
3303 #define PP_BIT_IDP 0x20
3304 #define PP_BIT_FDP 0x80
3305 #define PP_MSK_PSUM_MB 0x10
3306 #define PP_MSK_PSUM_UNITS 0x18
3307 #define PP_MSK_POFM 0x04
3308
3309 /* Get the number of partitions on the tape. As a side effect reads the
3310 mode page into the tape buffer. */
nbr_partitions(struct scsi_tape * STp)3311 static int nbr_partitions(struct scsi_tape *STp)
3312 {
3313 int result;
3314
3315 if (STp->ready != ST_READY)
3316 return (-EIO);
3317
3318 result = read_mode_page(STp, PART_PAGE, 1);
3319
3320 if (result) {
3321 DEBC_printk(STp, "Can't read medium partition page.\n");
3322 result = (-EIO);
3323 } else {
3324 result = (STp->buffer)->b_data[MODE_HEADER_LENGTH +
3325 PP_OFF_NBR_ADD_PARTS] + 1;
3326 DEBC_printk(STp, "Number of partitions %d.\n", result);
3327 }
3328
3329 return result;
3330 }
3331
3332
format_medium(struct scsi_tape * STp,int format)3333 static int format_medium(struct scsi_tape *STp, int format)
3334 {
3335 int result = 0;
3336 int timeout = STp->long_timeout;
3337 unsigned char scmd[MAX_COMMAND_SIZE];
3338 struct st_request *SRpnt;
3339
3340 memset(scmd, 0, MAX_COMMAND_SIZE);
3341 scmd[0] = FORMAT_UNIT;
3342 scmd[2] = format;
3343 if (STp->immediate) {
3344 scmd[1] |= 1; /* Don't wait for completion */
3345 timeout = STp->device->request_queue->rq_timeout;
3346 }
3347 DEBC_printk(STp, "Sending FORMAT MEDIUM\n");
3348 SRpnt = st_do_scsi(NULL, STp, scmd, 0, DMA_NONE,
3349 timeout, MAX_RETRIES, 1);
3350 if (!SRpnt)
3351 result = STp->buffer->syscall_result;
3352 return result;
3353 }
3354
3355
3356 /* Partition the tape into two partitions if size > 0 or one partition if
3357 size == 0.
3358
3359 The block descriptors are read and written because Sony SDT-7000 does not
3360 work without this (suggestion from Michael Schaefer <Michael.Schaefer@dlr.de>).
3361
3362 My HP C1533A drive returns only one partition size field. This is used to
3363 set the size of partition 1. There is no size field for the default partition.
3364 Michael Schaefer's Sony SDT-7000 returns two descriptors and the second is
3365 used to set the size of partition 1 (this is what the SCSI-3 standard specifies).
3366 The following algorithm is used to accommodate both drives: if the number of
3367 partition size fields is greater than the maximum number of additional partitions
3368 in the mode page, the second field is used. Otherwise the first field is used.
3369
3370 For Seagate DDS drives the page length must be 8 when no partitions is defined
3371 and 10 when 1 partition is defined (information from Eric Lee Green). This is
3372 is acceptable also to some other old drives and enforced if the first partition
3373 size field is used for the first additional partition size.
3374
3375 For drives that advertize SCSI-3 or newer, use the SSC-3 methods.
3376 */
partition_tape(struct scsi_tape * STp,int size)3377 static int partition_tape(struct scsi_tape *STp, int size)
3378 {
3379 int result;
3380 int target_partition;
3381 bool scsi3 = STp->device->scsi_level >= SCSI_3, needs_format = false;
3382 int pgo, psd_cnt, psdo;
3383 int psum = PP_MSK_PSUM_MB, units = 0;
3384 unsigned char *bp;
3385
3386 result = read_mode_page(STp, PART_PAGE, 0);
3387 if (result) {
3388 DEBC_printk(STp, "Can't read partition mode page.\n");
3389 return result;
3390 }
3391 target_partition = 1;
3392 if (size < 0) {
3393 target_partition = 0;
3394 size = -size;
3395 }
3396
3397 /* The mode page is in the buffer. Let's modify it and write it. */
3398 bp = (STp->buffer)->b_data;
3399 pgo = MODE_HEADER_LENGTH + bp[MH_OFF_BDESCS_LENGTH];
3400 DEBC_printk(STp, "Partition page length is %d bytes.\n",
3401 bp[pgo + MP_OFF_PAGE_LENGTH] + 2);
3402
3403 psd_cnt = (bp[pgo + MP_OFF_PAGE_LENGTH] + 2 - PART_PAGE_FIXED_LENGTH) / 2;
3404
3405 if (scsi3) {
3406 needs_format = (bp[pgo + PP_OFF_FLAGS] & PP_MSK_POFM) != 0;
3407 if (needs_format && size == 0) {
3408 /* No need to write the mode page when clearing
3409 * partitioning
3410 */
3411 DEBC_printk(STp, "Formatting tape with one partition.\n");
3412 result = format_medium(STp, 0);
3413 goto out;
3414 }
3415 if (needs_format) /* Leave the old value for HP DATs claiming SCSI_3 */
3416 psd_cnt = 2;
3417 if ((bp[pgo + PP_OFF_FLAGS] & PP_MSK_PSUM_UNITS) == PP_MSK_PSUM_UNITS) {
3418 /* Use units scaling for large partitions if the device
3419 * suggests it and no precision lost. Required for IBM
3420 * TS1140/50 drives that don't support MB units.
3421 */
3422 if (size >= 1000 && (size % 1000) == 0) {
3423 size /= 1000;
3424 psum = PP_MSK_PSUM_UNITS;
3425 units = 9; /* GB */
3426 }
3427 }
3428 /* Try it anyway if too large to specify in MB */
3429 if (psum == PP_MSK_PSUM_MB && size >= 65534) {
3430 size /= 1000;
3431 psum = PP_MSK_PSUM_UNITS;
3432 units = 9; /* GB */
3433 }
3434 }
3435
3436 if (size >= 65535 || /* Does not fit into two bytes */
3437 (target_partition == 0 && psd_cnt < 2)) {
3438 result = -EINVAL;
3439 goto out;
3440 }
3441
3442 psdo = pgo + PART_PAGE_FIXED_LENGTH;
3443 /* The second condition is for HP DDS which use only one partition size
3444 * descriptor
3445 */
3446 if (target_partition > 0 &&
3447 (psd_cnt > bp[pgo + PP_OFF_MAX_ADD_PARTS] ||
3448 bp[pgo + PP_OFF_MAX_ADD_PARTS] != 1)) {
3449 bp[psdo] = bp[psdo + 1] = 0xff; /* Rest to partition 0 */
3450 psdo += 2;
3451 }
3452 memset(bp + psdo, 0, bp[pgo + PP_OFF_NBR_ADD_PARTS] * 2);
3453
3454 DEBC_printk(STp, "psd_cnt %d, max.parts %d, nbr_parts %d\n",
3455 psd_cnt, bp[pgo + PP_OFF_MAX_ADD_PARTS],
3456 bp[pgo + PP_OFF_NBR_ADD_PARTS]);
3457
3458 if (size == 0) {
3459 bp[pgo + PP_OFF_NBR_ADD_PARTS] = 0;
3460 if (psd_cnt <= bp[pgo + PP_OFF_MAX_ADD_PARTS])
3461 bp[pgo + MP_OFF_PAGE_LENGTH] = 6;
3462 DEBC_printk(STp, "Formatting tape with one partition.\n");
3463 } else {
3464 bp[psdo] = (size >> 8) & 0xff;
3465 bp[psdo + 1] = size & 0xff;
3466 if (target_partition == 0)
3467 bp[psdo + 2] = bp[psdo + 3] = 0xff;
3468 bp[pgo + 3] = 1;
3469 if (bp[pgo + MP_OFF_PAGE_LENGTH] < 8)
3470 bp[pgo + MP_OFF_PAGE_LENGTH] = 8;
3471 DEBC_printk(STp,
3472 "Formatting tape with two partitions (%i = %d MB).\n",
3473 target_partition, units > 0 ? size * 1000 : size);
3474 }
3475 bp[pgo + PP_OFF_PART_UNITS] = 0;
3476 bp[pgo + PP_OFF_RESERVED] = 0;
3477 if (size != 1 || units != 0) {
3478 bp[pgo + PP_OFF_FLAGS] = PP_BIT_IDP | psum |
3479 (bp[pgo + PP_OFF_FLAGS] & 0x07);
3480 bp[pgo + PP_OFF_PART_UNITS] = units;
3481 } else
3482 bp[pgo + PP_OFF_FLAGS] = PP_BIT_FDP |
3483 (bp[pgo + PP_OFF_FLAGS] & 0x1f);
3484 bp[pgo + MP_OFF_PAGE_LENGTH] = 6 + psd_cnt * 2;
3485
3486 result = write_mode_page(STp, PART_PAGE, 1);
3487
3488 if (!result && needs_format)
3489 result = format_medium(STp, 1);
3490
3491 if (result) {
3492 st_printk(KERN_INFO, STp, "Partitioning of tape failed.\n");
3493 result = (-EIO);
3494 }
3495
3496 out:
3497 return result;
3498 }
3499
3500
3501
3502 /* The ioctl command */
st_ioctl_common(struct file * file,unsigned int cmd_in,void __user * p)3503 static long st_ioctl_common(struct file *file, unsigned int cmd_in, void __user *p)
3504 {
3505 int i, cmd_nr, cmd_type, bt;
3506 int retval = 0;
3507 unsigned int blk;
3508 struct scsi_tape *STp = file->private_data;
3509 struct st_modedef *STm;
3510 struct st_partstat *STps;
3511
3512 if (mutex_lock_interruptible(&STp->lock))
3513 return -ERESTARTSYS;
3514
3515 DEB(
3516 if (debugging && !STp->in_use) {
3517 st_printk(ST_DEB_MSG, STp, "Incorrect device.\n");
3518 retval = (-EIO);
3519 goto out;
3520 } ) /* end DEB */
3521
3522 STm = &(STp->modes[STp->current_mode]);
3523 STps = &(STp->ps[STp->partition]);
3524
3525 /*
3526 * If we are in the middle of error recovery, don't let anyone
3527 * else try and use this device. Also, if error recovery fails, it
3528 * may try and take the device offline, in which case all further
3529 * access to the device is prohibited.
3530 */
3531 retval = scsi_ioctl_block_when_processing_errors(STp->device, cmd_in,
3532 file->f_flags & O_NDELAY);
3533 if (retval)
3534 goto out;
3535
3536 cmd_type = _IOC_TYPE(cmd_in);
3537 cmd_nr = _IOC_NR(cmd_in);
3538
3539 if (cmd_type == _IOC_TYPE(MTIOCTOP) && cmd_nr == _IOC_NR(MTIOCTOP)) {
3540 struct mtop mtc;
3541
3542 if (_IOC_SIZE(cmd_in) != sizeof(mtc)) {
3543 retval = (-EINVAL);
3544 goto out;
3545 }
3546
3547 i = copy_from_user(&mtc, p, sizeof(struct mtop));
3548 if (i) {
3549 retval = (-EFAULT);
3550 goto out;
3551 }
3552
3553 if (mtc.mt_op == MTSETDRVBUFFER && !capable(CAP_SYS_ADMIN)) {
3554 st_printk(KERN_WARNING, STp,
3555 "MTSETDRVBUFFER only allowed for root.\n");
3556 retval = (-EPERM);
3557 goto out;
3558 }
3559 if (!STm->defined &&
3560 (mtc.mt_op != MTSETDRVBUFFER &&
3561 (mtc.mt_count & MT_ST_OPTIONS) == 0)) {
3562 retval = (-ENXIO);
3563 goto out;
3564 }
3565
3566 if (!STp->pos_unknown) {
3567
3568 if (STps->eof == ST_FM_HIT) {
3569 if (mtc.mt_op == MTFSF || mtc.mt_op == MTFSFM ||
3570 mtc.mt_op == MTEOM) {
3571 mtc.mt_count -= 1;
3572 if (STps->drv_file >= 0)
3573 STps->drv_file += 1;
3574 } else if (mtc.mt_op == MTBSF || mtc.mt_op == MTBSFM) {
3575 mtc.mt_count += 1;
3576 if (STps->drv_file >= 0)
3577 STps->drv_file += 1;
3578 }
3579 }
3580
3581 if (mtc.mt_op == MTSEEK) {
3582 /* Old position must be restored if partition will be
3583 changed */
3584 i = !STp->can_partitions ||
3585 (STp->new_partition != STp->partition);
3586 } else {
3587 i = mtc.mt_op == MTREW || mtc.mt_op == MTOFFL ||
3588 mtc.mt_op == MTRETEN || mtc.mt_op == MTEOM ||
3589 mtc.mt_op == MTLOCK || mtc.mt_op == MTLOAD ||
3590 mtc.mt_op == MTFSF || mtc.mt_op == MTFSFM ||
3591 mtc.mt_op == MTBSF || mtc.mt_op == MTBSFM ||
3592 mtc.mt_op == MTCOMPRESSION;
3593 }
3594 i = flush_buffer(STp, i);
3595 if (i < 0) {
3596 retval = i;
3597 goto out;
3598 }
3599 if (STps->rw == ST_WRITING &&
3600 (mtc.mt_op == MTREW || mtc.mt_op == MTOFFL ||
3601 mtc.mt_op == MTSEEK ||
3602 mtc.mt_op == MTBSF || mtc.mt_op == MTBSFM)) {
3603 i = st_int_ioctl(STp, MTWEOF, 1);
3604 if (i < 0) {
3605 retval = i;
3606 goto out;
3607 }
3608 if (mtc.mt_op == MTBSF || mtc.mt_op == MTBSFM)
3609 mtc.mt_count++;
3610 STps->rw = ST_IDLE;
3611 }
3612
3613 } else {
3614 /*
3615 * If there was a bus reset, block further access
3616 * to this device. If the user wants to rewind the tape,
3617 * then reset the flag and allow access again.
3618 */
3619 if (mtc.mt_op != MTREW &&
3620 mtc.mt_op != MTOFFL &&
3621 mtc.mt_op != MTRETEN &&
3622 mtc.mt_op != MTERASE &&
3623 mtc.mt_op != MTSEEK &&
3624 mtc.mt_op != MTEOM) {
3625 retval = (-EIO);
3626 goto out;
3627 }
3628 reset_state(STp);
3629 /* remove this when the midlevel properly clears was_reset */
3630 STp->device->was_reset = 0;
3631 }
3632
3633 if (mtc.mt_op != MTNOP && mtc.mt_op != MTSETBLK &&
3634 mtc.mt_op != MTSETDENSITY && mtc.mt_op != MTWSM &&
3635 mtc.mt_op != MTSETDRVBUFFER && mtc.mt_op != MTSETPART)
3636 STps->rw = ST_IDLE; /* Prevent automatic WEOF and fsf */
3637
3638 if (mtc.mt_op == MTOFFL && STp->door_locked != ST_UNLOCKED)
3639 do_door_lock(STp, 0); /* Ignore result! */
3640
3641 if (mtc.mt_op == MTSETDRVBUFFER &&
3642 (mtc.mt_count & MT_ST_OPTIONS) != 0) {
3643 retval = st_set_options(STp, mtc.mt_count);
3644 goto out;
3645 }
3646
3647 if (mtc.mt_op == MTSETPART) {
3648 if (!STp->can_partitions ||
3649 mtc.mt_count < 0 || mtc.mt_count >= ST_NBR_PARTITIONS) {
3650 retval = (-EINVAL);
3651 goto out;
3652 }
3653 if (mtc.mt_count >= STp->nbr_partitions &&
3654 (STp->nbr_partitions = nbr_partitions(STp)) < 0) {
3655 retval = (-EIO);
3656 goto out;
3657 }
3658 if (mtc.mt_count >= STp->nbr_partitions) {
3659 retval = (-EINVAL);
3660 goto out;
3661 }
3662 STp->new_partition = mtc.mt_count;
3663 retval = 0;
3664 goto out;
3665 }
3666
3667 if (mtc.mt_op == MTMKPART) {
3668 if (!STp->can_partitions) {
3669 retval = (-EINVAL);
3670 goto out;
3671 }
3672 i = do_load_unload(STp, file, 1);
3673 if (i < 0) {
3674 retval = i;
3675 goto out;
3676 }
3677 i = partition_tape(STp, mtc.mt_count);
3678 if (i < 0) {
3679 retval = i;
3680 goto out;
3681 }
3682 for (i = 0; i < ST_NBR_PARTITIONS; i++) {
3683 STp->ps[i].rw = ST_IDLE;
3684 STp->ps[i].at_sm = 0;
3685 STp->ps[i].last_block_valid = 0;
3686 }
3687 STp->partition = STp->new_partition = 0;
3688 STp->nbr_partitions = mtc.mt_count != 0 ? 2 : 1;
3689 STps->drv_block = STps->drv_file = 0;
3690 retval = 0;
3691 goto out;
3692 }
3693
3694 if (mtc.mt_op == MTSEEK) {
3695 i = set_location(STp, mtc.mt_count, STp->new_partition, 0);
3696 if (!STp->can_partitions)
3697 STp->ps[0].rw = ST_IDLE;
3698 retval = i;
3699 goto out;
3700 }
3701
3702 if (mtc.mt_op == MTUNLOAD || mtc.mt_op == MTOFFL) {
3703 retval = do_load_unload(STp, file, 0);
3704 goto out;
3705 }
3706
3707 if (mtc.mt_op == MTLOAD) {
3708 retval = do_load_unload(STp, file, max(1, mtc.mt_count));
3709 goto out;
3710 }
3711
3712 if (mtc.mt_op == MTLOCK || mtc.mt_op == MTUNLOCK) {
3713 retval = do_door_lock(STp, (mtc.mt_op == MTLOCK));
3714 goto out;
3715 }
3716
3717 if (STp->can_partitions && STp->ready == ST_READY &&
3718 (i = switch_partition(STp)) < 0) {
3719 retval = i;
3720 goto out;
3721 }
3722
3723 if (mtc.mt_op == MTCOMPRESSION)
3724 retval = st_compression(STp, (mtc.mt_count & 1));
3725 else
3726 retval = st_int_ioctl(STp, mtc.mt_op, mtc.mt_count);
3727 goto out;
3728 }
3729 if (!STm->defined) {
3730 retval = (-ENXIO);
3731 goto out;
3732 }
3733
3734 if ((i = flush_buffer(STp, 0)) < 0) {
3735 retval = i;
3736 goto out;
3737 }
3738 if (STp->can_partitions &&
3739 (i = switch_partition(STp)) < 0) {
3740 retval = i;
3741 goto out;
3742 }
3743
3744 if (cmd_type == _IOC_TYPE(MTIOCGET) && cmd_nr == _IOC_NR(MTIOCGET)) {
3745 struct mtget mt_status;
3746
3747 if (_IOC_SIZE(cmd_in) != sizeof(struct mtget)) {
3748 retval = (-EINVAL);
3749 goto out;
3750 }
3751
3752 mt_status.mt_type = STp->tape_type;
3753 mt_status.mt_dsreg =
3754 ((STp->block_size << MT_ST_BLKSIZE_SHIFT) & MT_ST_BLKSIZE_MASK) |
3755 ((STp->density << MT_ST_DENSITY_SHIFT) & MT_ST_DENSITY_MASK);
3756 mt_status.mt_blkno = STps->drv_block;
3757 mt_status.mt_fileno = STps->drv_file;
3758 if (STp->block_size != 0) {
3759 if (STps->rw == ST_WRITING)
3760 mt_status.mt_blkno +=
3761 (STp->buffer)->buffer_bytes / STp->block_size;
3762 else if (STps->rw == ST_READING)
3763 mt_status.mt_blkno -=
3764 ((STp->buffer)->buffer_bytes +
3765 STp->block_size - 1) / STp->block_size;
3766 }
3767
3768 mt_status.mt_gstat = 0;
3769 if (STp->drv_write_prot)
3770 mt_status.mt_gstat |= GMT_WR_PROT(0xffffffff);
3771 if (mt_status.mt_blkno == 0) {
3772 if (mt_status.mt_fileno == 0)
3773 mt_status.mt_gstat |= GMT_BOT(0xffffffff);
3774 else
3775 mt_status.mt_gstat |= GMT_EOF(0xffffffff);
3776 }
3777 mt_status.mt_erreg = (STp->recover_reg << MT_ST_SOFTERR_SHIFT);
3778 mt_status.mt_resid = STp->partition;
3779 if (STps->eof == ST_EOM_OK || STps->eof == ST_EOM_ERROR)
3780 mt_status.mt_gstat |= GMT_EOT(0xffffffff);
3781 else if (STps->eof >= ST_EOM_OK)
3782 mt_status.mt_gstat |= GMT_EOD(0xffffffff);
3783 if (STp->density == 1)
3784 mt_status.mt_gstat |= GMT_D_800(0xffffffff);
3785 else if (STp->density == 2)
3786 mt_status.mt_gstat |= GMT_D_1600(0xffffffff);
3787 else if (STp->density == 3)
3788 mt_status.mt_gstat |= GMT_D_6250(0xffffffff);
3789 if (STp->ready == ST_READY)
3790 mt_status.mt_gstat |= GMT_ONLINE(0xffffffff);
3791 if (STp->ready == ST_NO_TAPE)
3792 mt_status.mt_gstat |= GMT_DR_OPEN(0xffffffff);
3793 if (STps->at_sm)
3794 mt_status.mt_gstat |= GMT_SM(0xffffffff);
3795 if (STm->do_async_writes ||
3796 (STm->do_buffer_writes && STp->block_size != 0) ||
3797 STp->drv_buffer != 0)
3798 mt_status.mt_gstat |= GMT_IM_REP_EN(0xffffffff);
3799 if (STp->cleaning_req)
3800 mt_status.mt_gstat |= GMT_CLN(0xffffffff);
3801
3802 retval = put_user_mtget(p, &mt_status);
3803 if (retval)
3804 goto out;
3805
3806 STp->recover_reg = 0; /* Clear after read */
3807 goto out;
3808 } /* End of MTIOCGET */
3809 if (cmd_type == _IOC_TYPE(MTIOCPOS) && cmd_nr == _IOC_NR(MTIOCPOS)) {
3810 struct mtpos mt_pos;
3811 if (_IOC_SIZE(cmd_in) != sizeof(struct mtpos)) {
3812 retval = (-EINVAL);
3813 goto out;
3814 }
3815 if ((i = get_location(STp, &blk, &bt, 0)) < 0) {
3816 retval = i;
3817 goto out;
3818 }
3819 mt_pos.mt_blkno = blk;
3820 retval = put_user_mtpos(p, &mt_pos);
3821 goto out;
3822 }
3823 mutex_unlock(&STp->lock);
3824 switch (cmd_in) {
3825 case SCSI_IOCTL_STOP_UNIT:
3826 /* unload */
3827 retval = scsi_ioctl(STp->device, cmd_in, p);
3828 if (!retval) {
3829 STp->rew_at_close = 0;
3830 STp->ready = ST_NO_TAPE;
3831 }
3832 return retval;
3833
3834 case SCSI_IOCTL_GET_IDLUN:
3835 case SCSI_IOCTL_GET_BUS_NUMBER:
3836 break;
3837
3838 default:
3839 if ((cmd_in == SG_IO ||
3840 cmd_in == SCSI_IOCTL_SEND_COMMAND ||
3841 cmd_in == CDROM_SEND_PACKET) &&
3842 !capable(CAP_SYS_RAWIO))
3843 i = -EPERM;
3844 else
3845 i = scsi_cmd_ioctl(STp->disk->queue, STp->disk,
3846 file->f_mode, cmd_in, p);
3847 if (i != -ENOTTY)
3848 return i;
3849 break;
3850 }
3851 return -ENOTTY;
3852
3853 out:
3854 mutex_unlock(&STp->lock);
3855 return retval;
3856 }
3857
st_ioctl(struct file * file,unsigned int cmd_in,unsigned long arg)3858 static long st_ioctl(struct file *file, unsigned int cmd_in, unsigned long arg)
3859 {
3860 void __user *p = (void __user *)arg;
3861 struct scsi_tape *STp = file->private_data;
3862 int ret;
3863
3864 ret = st_ioctl_common(file, cmd_in, p);
3865 if (ret != -ENOTTY)
3866 return ret;
3867
3868 return scsi_ioctl(STp->device, cmd_in, p);
3869 }
3870
3871 #ifdef CONFIG_COMPAT
st_compat_ioctl(struct file * file,unsigned int cmd_in,unsigned long arg)3872 static long st_compat_ioctl(struct file *file, unsigned int cmd_in, unsigned long arg)
3873 {
3874 void __user *p = compat_ptr(arg);
3875 struct scsi_tape *STp = file->private_data;
3876 int ret;
3877
3878 /* argument conversion is handled using put_user_mtpos/put_user_mtget */
3879 switch (cmd_in) {
3880 case MTIOCPOS32:
3881 return st_ioctl_common(file, MTIOCPOS, p);
3882 case MTIOCGET32:
3883 return st_ioctl_common(file, MTIOCGET, p);
3884 }
3885
3886 ret = st_ioctl_common(file, cmd_in, p);
3887 if (ret != -ENOTTY)
3888 return ret;
3889
3890 return scsi_compat_ioctl(STp->device, cmd_in, p);
3891 }
3892 #endif
3893
3894
3895
3896 /* Try to allocate a new tape buffer. Calling function must not hold
3897 dev_arr_lock. */
new_tape_buffer(int need_dma,int max_sg)3898 static struct st_buffer *new_tape_buffer(int need_dma, int max_sg)
3899 {
3900 struct st_buffer *tb;
3901
3902 tb = kzalloc(sizeof(struct st_buffer), GFP_KERNEL);
3903 if (!tb) {
3904 printk(KERN_NOTICE "st: Can't allocate new tape buffer.\n");
3905 return NULL;
3906 }
3907 tb->frp_segs = 0;
3908 tb->use_sg = max_sg;
3909 tb->dma = need_dma;
3910 tb->buffer_size = 0;
3911
3912 tb->reserved_pages = kcalloc(max_sg, sizeof(struct page *),
3913 GFP_KERNEL);
3914 if (!tb->reserved_pages) {
3915 kfree(tb);
3916 return NULL;
3917 }
3918
3919 return tb;
3920 }
3921
3922
3923 /* Try to allocate enough space in the tape buffer */
3924 #define ST_MAX_ORDER 6
3925
enlarge_buffer(struct st_buffer * STbuffer,int new_size,int need_dma)3926 static int enlarge_buffer(struct st_buffer * STbuffer, int new_size, int need_dma)
3927 {
3928 int segs, max_segs, b_size, order, got;
3929 gfp_t priority;
3930
3931 if (new_size <= STbuffer->buffer_size)
3932 return 1;
3933
3934 if (STbuffer->buffer_size <= PAGE_SIZE)
3935 normalize_buffer(STbuffer); /* Avoid extra segment */
3936
3937 max_segs = STbuffer->use_sg;
3938
3939 priority = GFP_KERNEL | __GFP_NOWARN;
3940 if (need_dma)
3941 priority |= GFP_DMA;
3942
3943 if (STbuffer->cleared)
3944 priority |= __GFP_ZERO;
3945
3946 if (STbuffer->frp_segs) {
3947 order = STbuffer->reserved_page_order;
3948 b_size = PAGE_SIZE << order;
3949 } else {
3950 for (b_size = PAGE_SIZE, order = 0;
3951 order < ST_MAX_ORDER &&
3952 max_segs * (PAGE_SIZE << order) < new_size;
3953 order++, b_size *= 2)
3954 ; /* empty */
3955 STbuffer->reserved_page_order = order;
3956 }
3957 if (max_segs * (PAGE_SIZE << order) < new_size) {
3958 if (order == ST_MAX_ORDER)
3959 return 0;
3960 normalize_buffer(STbuffer);
3961 return enlarge_buffer(STbuffer, new_size, need_dma);
3962 }
3963
3964 for (segs = STbuffer->frp_segs, got = STbuffer->buffer_size;
3965 segs < max_segs && got < new_size;) {
3966 struct page *page;
3967
3968 page = alloc_pages(priority, order);
3969 if (!page) {
3970 DEB(STbuffer->buffer_size = got);
3971 normalize_buffer(STbuffer);
3972 return 0;
3973 }
3974
3975 STbuffer->frp_segs += 1;
3976 got += b_size;
3977 STbuffer->buffer_size = got;
3978 STbuffer->reserved_pages[segs] = page;
3979 segs++;
3980 }
3981 STbuffer->b_data = page_address(STbuffer->reserved_pages[0]);
3982
3983 return 1;
3984 }
3985
3986
3987 /* Make sure that no data from previous user is in the internal buffer */
clear_buffer(struct st_buffer * st_bp)3988 static void clear_buffer(struct st_buffer * st_bp)
3989 {
3990 int i;
3991
3992 for (i=0; i < st_bp->frp_segs; i++)
3993 memset(page_address(st_bp->reserved_pages[i]), 0,
3994 PAGE_SIZE << st_bp->reserved_page_order);
3995 st_bp->cleared = 1;
3996 }
3997
3998
3999 /* Release the extra buffer */
normalize_buffer(struct st_buffer * STbuffer)4000 static void normalize_buffer(struct st_buffer * STbuffer)
4001 {
4002 int i, order = STbuffer->reserved_page_order;
4003
4004 for (i = 0; i < STbuffer->frp_segs; i++) {
4005 __free_pages(STbuffer->reserved_pages[i], order);
4006 STbuffer->buffer_size -= (PAGE_SIZE << order);
4007 }
4008 STbuffer->frp_segs = 0;
4009 STbuffer->sg_segs = 0;
4010 STbuffer->reserved_page_order = 0;
4011 STbuffer->map_data.offset = 0;
4012 }
4013
4014
4015 /* Move data from the user buffer to the tape buffer. Returns zero (success) or
4016 negative error code. */
append_to_buffer(const char __user * ubp,struct st_buffer * st_bp,int do_count)4017 static int append_to_buffer(const char __user *ubp, struct st_buffer * st_bp, int do_count)
4018 {
4019 int i, cnt, res, offset;
4020 int length = PAGE_SIZE << st_bp->reserved_page_order;
4021
4022 for (i = 0, offset = st_bp->buffer_bytes;
4023 i < st_bp->frp_segs && offset >= length; i++)
4024 offset -= length;
4025 if (i == st_bp->frp_segs) { /* Should never happen */
4026 printk(KERN_WARNING "st: append_to_buffer offset overflow.\n");
4027 return (-EIO);
4028 }
4029 for (; i < st_bp->frp_segs && do_count > 0; i++) {
4030 struct page *page = st_bp->reserved_pages[i];
4031 cnt = length - offset < do_count ? length - offset : do_count;
4032 res = copy_from_user(page_address(page) + offset, ubp, cnt);
4033 if (res)
4034 return (-EFAULT);
4035 do_count -= cnt;
4036 st_bp->buffer_bytes += cnt;
4037 ubp += cnt;
4038 offset = 0;
4039 }
4040 if (do_count) /* Should never happen */
4041 return (-EIO);
4042
4043 return 0;
4044 }
4045
4046
4047 /* Move data from the tape buffer to the user buffer. Returns zero (success) or
4048 negative error code. */
from_buffer(struct st_buffer * st_bp,char __user * ubp,int do_count)4049 static int from_buffer(struct st_buffer * st_bp, char __user *ubp, int do_count)
4050 {
4051 int i, cnt, res, offset;
4052 int length = PAGE_SIZE << st_bp->reserved_page_order;
4053
4054 for (i = 0, offset = st_bp->read_pointer;
4055 i < st_bp->frp_segs && offset >= length; i++)
4056 offset -= length;
4057 if (i == st_bp->frp_segs) { /* Should never happen */
4058 printk(KERN_WARNING "st: from_buffer offset overflow.\n");
4059 return (-EIO);
4060 }
4061 for (; i < st_bp->frp_segs && do_count > 0; i++) {
4062 struct page *page = st_bp->reserved_pages[i];
4063 cnt = length - offset < do_count ? length - offset : do_count;
4064 res = copy_to_user(ubp, page_address(page) + offset, cnt);
4065 if (res)
4066 return (-EFAULT);
4067 do_count -= cnt;
4068 st_bp->buffer_bytes -= cnt;
4069 st_bp->read_pointer += cnt;
4070 ubp += cnt;
4071 offset = 0;
4072 }
4073 if (do_count) /* Should never happen */
4074 return (-EIO);
4075
4076 return 0;
4077 }
4078
4079
4080 /* Move data towards start of buffer */
move_buffer_data(struct st_buffer * st_bp,int offset)4081 static void move_buffer_data(struct st_buffer * st_bp, int offset)
4082 {
4083 int src_seg, dst_seg, src_offset = 0, dst_offset;
4084 int count, total;
4085 int length = PAGE_SIZE << st_bp->reserved_page_order;
4086
4087 if (offset == 0)
4088 return;
4089
4090 total=st_bp->buffer_bytes - offset;
4091 for (src_seg=0; src_seg < st_bp->frp_segs; src_seg++) {
4092 src_offset = offset;
4093 if (src_offset < length)
4094 break;
4095 offset -= length;
4096 }
4097
4098 st_bp->buffer_bytes = st_bp->read_pointer = total;
4099 for (dst_seg=dst_offset=0; total > 0; ) {
4100 struct page *dpage = st_bp->reserved_pages[dst_seg];
4101 struct page *spage = st_bp->reserved_pages[src_seg];
4102
4103 count = min(length - dst_offset, length - src_offset);
4104 memmove(page_address(dpage) + dst_offset,
4105 page_address(spage) + src_offset, count);
4106 src_offset += count;
4107 if (src_offset >= length) {
4108 src_seg++;
4109 src_offset = 0;
4110 }
4111 dst_offset += count;
4112 if (dst_offset >= length) {
4113 dst_seg++;
4114 dst_offset = 0;
4115 }
4116 total -= count;
4117 }
4118 }
4119
4120 /* Validate the options from command line or module parameters */
validate_options(void)4121 static void validate_options(void)
4122 {
4123 if (buffer_kbs > 0)
4124 st_fixed_buffer_size = buffer_kbs * ST_KILOBYTE;
4125 if (max_sg_segs >= ST_FIRST_SG)
4126 st_max_sg_segs = max_sg_segs;
4127 }
4128
4129 #ifndef MODULE
4130 /* Set the boot options. Syntax is defined in Documenation/scsi/st.txt.
4131 */
st_setup(char * str)4132 static int __init st_setup(char *str)
4133 {
4134 int i, len, ints[5];
4135 char *stp;
4136
4137 stp = get_options(str, ARRAY_SIZE(ints), ints);
4138
4139 if (ints[0] > 0) {
4140 for (i = 0; i < ints[0] && i < ARRAY_SIZE(parms); i++)
4141 if (parms[i].val)
4142 *parms[i].val = ints[i + 1];
4143 } else {
4144 while (stp != NULL) {
4145 for (i = 0; i < ARRAY_SIZE(parms); i++) {
4146 len = strlen(parms[i].name);
4147 if (!strncmp(stp, parms[i].name, len) &&
4148 (*(stp + len) == ':' || *(stp + len) == '=')) {
4149 if (parms[i].val)
4150 *parms[i].val =
4151 simple_strtoul(stp + len + 1, NULL, 0);
4152 else
4153 printk(KERN_WARNING "st: Obsolete parameter %s\n",
4154 parms[i].name);
4155 break;
4156 }
4157 }
4158 if (i >= ARRAY_SIZE(parms))
4159 printk(KERN_WARNING "st: invalid parameter in '%s'\n",
4160 stp);
4161 stp = strchr(stp, ',');
4162 if (stp)
4163 stp++;
4164 }
4165 }
4166
4167 validate_options();
4168
4169 return 1;
4170 }
4171
4172 __setup("st=", st_setup);
4173
4174 #endif
4175
4176 static const struct file_operations st_fops =
4177 {
4178 .owner = THIS_MODULE,
4179 .read = st_read,
4180 .write = st_write,
4181 .unlocked_ioctl = st_ioctl,
4182 #ifdef CONFIG_COMPAT
4183 .compat_ioctl = st_compat_ioctl,
4184 #endif
4185 .open = st_open,
4186 .flush = st_flush,
4187 .release = st_release,
4188 .llseek = noop_llseek,
4189 };
4190
create_one_cdev(struct scsi_tape * tape,int mode,int rew)4191 static int create_one_cdev(struct scsi_tape *tape, int mode, int rew)
4192 {
4193 int i, error;
4194 dev_t cdev_devno;
4195 struct cdev *cdev;
4196 struct device *dev;
4197 struct st_modedef *STm = &(tape->modes[mode]);
4198 char name[10];
4199 int dev_num = tape->index;
4200
4201 cdev_devno = MKDEV(SCSI_TAPE_MAJOR, TAPE_MINOR(dev_num, mode, rew));
4202
4203 cdev = cdev_alloc();
4204 if (!cdev) {
4205 pr_err("st%d: out of memory. Device not attached.\n", dev_num);
4206 error = -ENOMEM;
4207 goto out;
4208 }
4209 cdev->owner = THIS_MODULE;
4210 cdev->ops = &st_fops;
4211 STm->cdevs[rew] = cdev;
4212
4213 error = cdev_add(cdev, cdev_devno, 1);
4214 if (error) {
4215 pr_err("st%d: Can't add %s-rewind mode %d\n", dev_num,
4216 rew ? "non" : "auto", mode);
4217 pr_err("st%d: Device not attached.\n", dev_num);
4218 goto out_free;
4219 }
4220
4221 i = mode << (4 - ST_NBR_MODE_BITS);
4222 snprintf(name, 10, "%s%s%s", rew ? "n" : "",
4223 tape->disk->disk_name, st_formats[i]);
4224
4225 dev = device_create(&st_sysfs_class, &tape->device->sdev_gendev,
4226 cdev_devno, &tape->modes[mode], "%s", name);
4227 if (IS_ERR(dev)) {
4228 pr_err("st%d: device_create failed\n", dev_num);
4229 error = PTR_ERR(dev);
4230 goto out_free;
4231 }
4232
4233 STm->devs[rew] = dev;
4234
4235 return 0;
4236 out_free:
4237 cdev_del(STm->cdevs[rew]);
4238 out:
4239 STm->cdevs[rew] = NULL;
4240 STm->devs[rew] = NULL;
4241 return error;
4242 }
4243
create_cdevs(struct scsi_tape * tape)4244 static int create_cdevs(struct scsi_tape *tape)
4245 {
4246 int mode, error;
4247 for (mode = 0; mode < ST_NBR_MODES; ++mode) {
4248 error = create_one_cdev(tape, mode, 0);
4249 if (error)
4250 return error;
4251 error = create_one_cdev(tape, mode, 1);
4252 if (error)
4253 return error;
4254 }
4255
4256 return sysfs_create_link(&tape->device->sdev_gendev.kobj,
4257 &tape->modes[0].devs[0]->kobj, "tape");
4258 }
4259
remove_cdevs(struct scsi_tape * tape)4260 static void remove_cdevs(struct scsi_tape *tape)
4261 {
4262 int mode, rew;
4263 sysfs_remove_link(&tape->device->sdev_gendev.kobj, "tape");
4264 for (mode = 0; mode < ST_NBR_MODES; mode++) {
4265 struct st_modedef *STm = &(tape->modes[mode]);
4266 for (rew = 0; rew < 2; rew++) {
4267 if (STm->cdevs[rew])
4268 cdev_del(STm->cdevs[rew]);
4269 if (STm->devs[rew])
4270 device_unregister(STm->devs[rew]);
4271 }
4272 }
4273 }
4274
st_probe(struct device * dev)4275 static int st_probe(struct device *dev)
4276 {
4277 struct scsi_device *SDp = to_scsi_device(dev);
4278 struct gendisk *disk = NULL;
4279 struct scsi_tape *tpnt = NULL;
4280 struct st_modedef *STm;
4281 struct st_partstat *STps;
4282 struct st_buffer *buffer;
4283 int i, error;
4284 char *stp;
4285
4286 if (SDp->type != TYPE_TAPE)
4287 return -ENODEV;
4288 if ((stp = st_incompatible(SDp))) {
4289 sdev_printk(KERN_INFO, SDp,
4290 "OnStream tapes are no longer supported;\n");
4291 sdev_printk(KERN_INFO, SDp,
4292 "please mail to linux-scsi@vger.kernel.org.\n");
4293 return -ENODEV;
4294 }
4295
4296 scsi_autopm_get_device(SDp);
4297 i = queue_max_segments(SDp->request_queue);
4298 if (st_max_sg_segs < i)
4299 i = st_max_sg_segs;
4300 buffer = new_tape_buffer((SDp->host)->unchecked_isa_dma, i);
4301 if (buffer == NULL) {
4302 sdev_printk(KERN_ERR, SDp,
4303 "st: Can't allocate new tape buffer. "
4304 "Device not attached.\n");
4305 goto out;
4306 }
4307
4308 disk = alloc_disk(1);
4309 if (!disk) {
4310 sdev_printk(KERN_ERR, SDp,
4311 "st: out of memory. Device not attached.\n");
4312 goto out_buffer_free;
4313 }
4314
4315 tpnt = kzalloc(sizeof(struct scsi_tape), GFP_KERNEL);
4316 if (tpnt == NULL) {
4317 sdev_printk(KERN_ERR, SDp,
4318 "st: Can't allocate device descriptor.\n");
4319 goto out_put_disk;
4320 }
4321 kref_init(&tpnt->kref);
4322 tpnt->disk = disk;
4323 disk->private_data = &tpnt->driver;
4324 /* SCSI tape doesn't register this gendisk via add_disk(). Manually
4325 * take queue reference that release_disk() expects. */
4326 if (!blk_get_queue(SDp->request_queue))
4327 goto out_put_disk;
4328 disk->queue = SDp->request_queue;
4329 tpnt->driver = &st_template;
4330
4331 tpnt->device = SDp;
4332 if (SDp->scsi_level <= 2)
4333 tpnt->tape_type = MT_ISSCSI1;
4334 else
4335 tpnt->tape_type = MT_ISSCSI2;
4336
4337 tpnt->buffer = buffer;
4338 tpnt->buffer->last_SRpnt = NULL;
4339
4340 tpnt->inited = 0;
4341 tpnt->dirty = 0;
4342 tpnt->in_use = 0;
4343 tpnt->drv_buffer = 1; /* Try buffering if no mode sense */
4344 tpnt->restr_dma = (SDp->host)->unchecked_isa_dma;
4345 tpnt->use_pf = (SDp->scsi_level >= SCSI_2);
4346 tpnt->density = 0;
4347 tpnt->do_auto_lock = ST_AUTO_LOCK;
4348 tpnt->can_bsr = (SDp->scsi_level > 2 ? 1 : ST_IN_FILE_POS); /* BSR mandatory in SCSI3 */
4349 tpnt->can_partitions = 0;
4350 tpnt->two_fm = ST_TWO_FM;
4351 tpnt->fast_mteom = ST_FAST_MTEOM;
4352 tpnt->scsi2_logical = ST_SCSI2LOGICAL;
4353 tpnt->sili = ST_SILI;
4354 tpnt->immediate = ST_NOWAIT;
4355 tpnt->immediate_filemark = 0;
4356 tpnt->default_drvbuffer = 0xff; /* No forced buffering */
4357 tpnt->partition = 0;
4358 tpnt->new_partition = 0;
4359 tpnt->nbr_partitions = 0;
4360 blk_queue_rq_timeout(tpnt->device->request_queue, ST_TIMEOUT);
4361 tpnt->long_timeout = ST_LONG_TIMEOUT;
4362 tpnt->try_dio = try_direct_io && !SDp->host->unchecked_isa_dma;
4363
4364 for (i = 0; i < ST_NBR_MODES; i++) {
4365 STm = &(tpnt->modes[i]);
4366 STm->defined = 0;
4367 STm->sysv = ST_SYSV;
4368 STm->defaults_for_writes = 0;
4369 STm->do_async_writes = ST_ASYNC_WRITES;
4370 STm->do_buffer_writes = ST_BUFFER_WRITES;
4371 STm->do_read_ahead = ST_READ_AHEAD;
4372 STm->default_compression = ST_DONT_TOUCH;
4373 STm->default_blksize = (-1); /* No forced size */
4374 STm->default_density = (-1); /* No forced density */
4375 STm->tape = tpnt;
4376 }
4377
4378 for (i = 0; i < ST_NBR_PARTITIONS; i++) {
4379 STps = &(tpnt->ps[i]);
4380 STps->rw = ST_IDLE;
4381 STps->eof = ST_NOEOF;
4382 STps->at_sm = 0;
4383 STps->last_block_valid = 0;
4384 STps->drv_block = (-1);
4385 STps->drv_file = (-1);
4386 }
4387
4388 tpnt->current_mode = 0;
4389 tpnt->modes[0].defined = 1;
4390
4391 tpnt->density_changed = tpnt->compression_changed =
4392 tpnt->blksize_changed = 0;
4393 mutex_init(&tpnt->lock);
4394
4395 idr_preload(GFP_KERNEL);
4396 spin_lock(&st_index_lock);
4397 error = idr_alloc(&st_index_idr, tpnt, 0, ST_MAX_TAPES + 1, GFP_NOWAIT);
4398 spin_unlock(&st_index_lock);
4399 idr_preload_end();
4400 if (error < 0) {
4401 pr_warn("st: idr allocation failed: %d\n", error);
4402 goto out_put_queue;
4403 }
4404 tpnt->index = error;
4405 sprintf(disk->disk_name, "st%d", tpnt->index);
4406 tpnt->stats = kzalloc(sizeof(struct scsi_tape_stats), GFP_KERNEL);
4407 if (tpnt->stats == NULL) {
4408 sdev_printk(KERN_ERR, SDp,
4409 "st: Can't allocate statistics.\n");
4410 goto out_idr_remove;
4411 }
4412
4413 dev_set_drvdata(dev, tpnt);
4414
4415
4416 error = create_cdevs(tpnt);
4417 if (error)
4418 goto out_remove_devs;
4419 scsi_autopm_put_device(SDp);
4420
4421 sdev_printk(KERN_NOTICE, SDp,
4422 "Attached scsi tape %s\n", tape_name(tpnt));
4423 sdev_printk(KERN_INFO, SDp, "%s: try direct i/o: %s (alignment %d B)\n",
4424 tape_name(tpnt), tpnt->try_dio ? "yes" : "no",
4425 queue_dma_alignment(SDp->request_queue) + 1);
4426
4427 return 0;
4428
4429 out_remove_devs:
4430 remove_cdevs(tpnt);
4431 kfree(tpnt->stats);
4432 out_idr_remove:
4433 spin_lock(&st_index_lock);
4434 idr_remove(&st_index_idr, tpnt->index);
4435 spin_unlock(&st_index_lock);
4436 out_put_queue:
4437 blk_put_queue(disk->queue);
4438 out_put_disk:
4439 put_disk(disk);
4440 kfree(tpnt);
4441 out_buffer_free:
4442 kfree(buffer);
4443 out:
4444 scsi_autopm_put_device(SDp);
4445 return -ENODEV;
4446 };
4447
4448
st_remove(struct device * dev)4449 static int st_remove(struct device *dev)
4450 {
4451 struct scsi_tape *tpnt = dev_get_drvdata(dev);
4452 int index = tpnt->index;
4453
4454 scsi_autopm_get_device(to_scsi_device(dev));
4455 remove_cdevs(tpnt);
4456
4457 mutex_lock(&st_ref_mutex);
4458 kref_put(&tpnt->kref, scsi_tape_release);
4459 mutex_unlock(&st_ref_mutex);
4460 spin_lock(&st_index_lock);
4461 idr_remove(&st_index_idr, index);
4462 spin_unlock(&st_index_lock);
4463 return 0;
4464 }
4465
4466 /**
4467 * scsi_tape_release - Called to free the Scsi_Tape structure
4468 * @kref: pointer to embedded kref
4469 *
4470 * st_ref_mutex must be held entering this routine. Because it is
4471 * called on last put, you should always use the scsi_tape_get()
4472 * scsi_tape_put() helpers which manipulate the semaphore directly
4473 * and never do a direct kref_put().
4474 **/
scsi_tape_release(struct kref * kref)4475 static void scsi_tape_release(struct kref *kref)
4476 {
4477 struct scsi_tape *tpnt = to_scsi_tape(kref);
4478 struct gendisk *disk = tpnt->disk;
4479
4480 tpnt->device = NULL;
4481
4482 if (tpnt->buffer) {
4483 normalize_buffer(tpnt->buffer);
4484 kfree(tpnt->buffer->reserved_pages);
4485 kfree(tpnt->buffer);
4486 }
4487
4488 disk->private_data = NULL;
4489 put_disk(disk);
4490 kfree(tpnt->stats);
4491 kfree(tpnt);
4492 return;
4493 }
4494
4495 static struct class st_sysfs_class = {
4496 .name = "scsi_tape",
4497 .dev_groups = st_dev_groups,
4498 };
4499
init_st(void)4500 static int __init init_st(void)
4501 {
4502 int err;
4503
4504 validate_options();
4505
4506 printk(KERN_INFO "st: Version %s, fixed bufsize %d, s/g segs %d\n",
4507 verstr, st_fixed_buffer_size, st_max_sg_segs);
4508
4509 debugging = (debug_flag > 0) ? debug_flag : NO_DEBUG;
4510 if (debugging) {
4511 printk(KERN_INFO "st: Debugging enabled debug_flag = %d\n",
4512 debugging);
4513 }
4514
4515 err = class_register(&st_sysfs_class);
4516 if (err) {
4517 pr_err("Unable register sysfs class for SCSI tapes\n");
4518 return err;
4519 }
4520
4521 err = register_chrdev_region(MKDEV(SCSI_TAPE_MAJOR, 0),
4522 ST_MAX_TAPE_ENTRIES, "st");
4523 if (err) {
4524 printk(KERN_ERR "Unable to get major %d for SCSI tapes\n",
4525 SCSI_TAPE_MAJOR);
4526 goto err_class;
4527 }
4528
4529 err = scsi_register_driver(&st_template.gendrv);
4530 if (err)
4531 goto err_chrdev;
4532
4533 return 0;
4534
4535 err_chrdev:
4536 unregister_chrdev_region(MKDEV(SCSI_TAPE_MAJOR, 0),
4537 ST_MAX_TAPE_ENTRIES);
4538 err_class:
4539 class_unregister(&st_sysfs_class);
4540 return err;
4541 }
4542
exit_st(void)4543 static void __exit exit_st(void)
4544 {
4545 scsi_unregister_driver(&st_template.gendrv);
4546 unregister_chrdev_region(MKDEV(SCSI_TAPE_MAJOR, 0),
4547 ST_MAX_TAPE_ENTRIES);
4548 class_unregister(&st_sysfs_class);
4549 idr_destroy(&st_index_idr);
4550 printk(KERN_INFO "st: Unloaded.\n");
4551 }
4552
4553 module_init(init_st);
4554 module_exit(exit_st);
4555
4556
4557 /* The sysfs driver interface. Read-only at the moment */
try_direct_io_show(struct device_driver * ddp,char * buf)4558 static ssize_t try_direct_io_show(struct device_driver *ddp, char *buf)
4559 {
4560 return scnprintf(buf, PAGE_SIZE, "%d\n", try_direct_io);
4561 }
4562 static DRIVER_ATTR_RO(try_direct_io);
4563
fixed_buffer_size_show(struct device_driver * ddp,char * buf)4564 static ssize_t fixed_buffer_size_show(struct device_driver *ddp, char *buf)
4565 {
4566 return scnprintf(buf, PAGE_SIZE, "%d\n", st_fixed_buffer_size);
4567 }
4568 static DRIVER_ATTR_RO(fixed_buffer_size);
4569
max_sg_segs_show(struct device_driver * ddp,char * buf)4570 static ssize_t max_sg_segs_show(struct device_driver *ddp, char *buf)
4571 {
4572 return scnprintf(buf, PAGE_SIZE, "%d\n", st_max_sg_segs);
4573 }
4574 static DRIVER_ATTR_RO(max_sg_segs);
4575
version_show(struct device_driver * ddd,char * buf)4576 static ssize_t version_show(struct device_driver *ddd, char *buf)
4577 {
4578 return scnprintf(buf, PAGE_SIZE, "[%s]\n", verstr);
4579 }
4580 static DRIVER_ATTR_RO(version);
4581
4582 #if DEBUG
debug_flag_store(struct device_driver * ddp,const char * buf,size_t count)4583 static ssize_t debug_flag_store(struct device_driver *ddp,
4584 const char *buf, size_t count)
4585 {
4586 /* We only care what the first byte of the data is the rest is unused.
4587 * if it's a '1' we turn on debug and if it's a '0' we disable it. All
4588 * other values have -EINVAL returned if they are passed in.
4589 */
4590 if (count > 0) {
4591 if (buf[0] == '0') {
4592 debugging = NO_DEBUG;
4593 return count;
4594 } else if (buf[0] == '1') {
4595 debugging = 1;
4596 return count;
4597 }
4598 }
4599 return -EINVAL;
4600 }
4601
debug_flag_show(struct device_driver * ddp,char * buf)4602 static ssize_t debug_flag_show(struct device_driver *ddp, char *buf)
4603 {
4604 return scnprintf(buf, PAGE_SIZE, "%d\n", debugging);
4605 }
4606 static DRIVER_ATTR_RW(debug_flag);
4607 #endif
4608
4609 static struct attribute *st_drv_attrs[] = {
4610 &driver_attr_try_direct_io.attr,
4611 &driver_attr_fixed_buffer_size.attr,
4612 &driver_attr_max_sg_segs.attr,
4613 &driver_attr_version.attr,
4614 #if DEBUG
4615 &driver_attr_debug_flag.attr,
4616 #endif
4617 NULL,
4618 };
4619 ATTRIBUTE_GROUPS(st_drv);
4620
4621 /* The sysfs simple class interface */
4622 static ssize_t
defined_show(struct device * dev,struct device_attribute * attr,char * buf)4623 defined_show(struct device *dev, struct device_attribute *attr, char *buf)
4624 {
4625 struct st_modedef *STm = dev_get_drvdata(dev);
4626 ssize_t l = 0;
4627
4628 l = snprintf(buf, PAGE_SIZE, "%d\n", STm->defined);
4629 return l;
4630 }
4631 static DEVICE_ATTR_RO(defined);
4632
4633 static ssize_t
default_blksize_show(struct device * dev,struct device_attribute * attr,char * buf)4634 default_blksize_show(struct device *dev, struct device_attribute *attr,
4635 char *buf)
4636 {
4637 struct st_modedef *STm = dev_get_drvdata(dev);
4638 ssize_t l = 0;
4639
4640 l = snprintf(buf, PAGE_SIZE, "%d\n", STm->default_blksize);
4641 return l;
4642 }
4643 static DEVICE_ATTR_RO(default_blksize);
4644
4645 static ssize_t
default_density_show(struct device * dev,struct device_attribute * attr,char * buf)4646 default_density_show(struct device *dev, struct device_attribute *attr,
4647 char *buf)
4648 {
4649 struct st_modedef *STm = dev_get_drvdata(dev);
4650 ssize_t l = 0;
4651 char *fmt;
4652
4653 fmt = STm->default_density >= 0 ? "0x%02x\n" : "%d\n";
4654 l = snprintf(buf, PAGE_SIZE, fmt, STm->default_density);
4655 return l;
4656 }
4657 static DEVICE_ATTR_RO(default_density);
4658
4659 static ssize_t
default_compression_show(struct device * dev,struct device_attribute * attr,char * buf)4660 default_compression_show(struct device *dev, struct device_attribute *attr,
4661 char *buf)
4662 {
4663 struct st_modedef *STm = dev_get_drvdata(dev);
4664 ssize_t l = 0;
4665
4666 l = snprintf(buf, PAGE_SIZE, "%d\n", STm->default_compression - 1);
4667 return l;
4668 }
4669 static DEVICE_ATTR_RO(default_compression);
4670
4671 static ssize_t
options_show(struct device * dev,struct device_attribute * attr,char * buf)4672 options_show(struct device *dev, struct device_attribute *attr, char *buf)
4673 {
4674 struct st_modedef *STm = dev_get_drvdata(dev);
4675 struct scsi_tape *STp = STm->tape;
4676 int options;
4677 ssize_t l = 0;
4678
4679 options = STm->do_buffer_writes ? MT_ST_BUFFER_WRITES : 0;
4680 options |= STm->do_async_writes ? MT_ST_ASYNC_WRITES : 0;
4681 options |= STm->do_read_ahead ? MT_ST_READ_AHEAD : 0;
4682 DEB( options |= debugging ? MT_ST_DEBUGGING : 0 );
4683 options |= STp->two_fm ? MT_ST_TWO_FM : 0;
4684 options |= STp->fast_mteom ? MT_ST_FAST_MTEOM : 0;
4685 options |= STm->defaults_for_writes ? MT_ST_DEF_WRITES : 0;
4686 options |= STp->can_bsr ? MT_ST_CAN_BSR : 0;
4687 options |= STp->omit_blklims ? MT_ST_NO_BLKLIMS : 0;
4688 options |= STp->can_partitions ? MT_ST_CAN_PARTITIONS : 0;
4689 options |= STp->scsi2_logical ? MT_ST_SCSI2LOGICAL : 0;
4690 options |= STm->sysv ? MT_ST_SYSV : 0;
4691 options |= STp->immediate ? MT_ST_NOWAIT : 0;
4692 options |= STp->immediate_filemark ? MT_ST_NOWAIT_EOF : 0;
4693 options |= STp->sili ? MT_ST_SILI : 0;
4694
4695 l = snprintf(buf, PAGE_SIZE, "0x%08x\n", options);
4696 return l;
4697 }
4698 static DEVICE_ATTR_RO(options);
4699
4700 /* Support for tape stats */
4701
4702 /**
4703 * read_cnt_show - return read count - count of reads made from tape drive
4704 * @dev: struct device
4705 * @attr: attribute structure
4706 * @buf: buffer to return formatted data in
4707 */
read_cnt_show(struct device * dev,struct device_attribute * attr,char * buf)4708 static ssize_t read_cnt_show(struct device *dev,
4709 struct device_attribute *attr, char *buf)
4710 {
4711 struct st_modedef *STm = dev_get_drvdata(dev);
4712
4713 return sprintf(buf, "%lld",
4714 (long long)atomic64_read(&STm->tape->stats->read_cnt));
4715 }
4716 static DEVICE_ATTR_RO(read_cnt);
4717
4718 /**
4719 * read_byte_cnt_show - return read byte count - tape drives
4720 * may use blocks less than 512 bytes this gives the raw byte count of
4721 * of data read from the tape drive.
4722 * @dev: struct device
4723 * @attr: attribute structure
4724 * @buf: buffer to return formatted data in
4725 */
read_byte_cnt_show(struct device * dev,struct device_attribute * attr,char * buf)4726 static ssize_t read_byte_cnt_show(struct device *dev,
4727 struct device_attribute *attr, char *buf)
4728 {
4729 struct st_modedef *STm = dev_get_drvdata(dev);
4730
4731 return sprintf(buf, "%lld",
4732 (long long)atomic64_read(&STm->tape->stats->read_byte_cnt));
4733 }
4734 static DEVICE_ATTR_RO(read_byte_cnt);
4735
4736 /**
4737 * read_ns_show - return read ns - overall time spent waiting on reads in ns.
4738 * @dev: struct device
4739 * @attr: attribute structure
4740 * @buf: buffer to return formatted data in
4741 */
read_ns_show(struct device * dev,struct device_attribute * attr,char * buf)4742 static ssize_t read_ns_show(struct device *dev,
4743 struct device_attribute *attr, char *buf)
4744 {
4745 struct st_modedef *STm = dev_get_drvdata(dev);
4746
4747 return sprintf(buf, "%lld",
4748 (long long)atomic64_read(&STm->tape->stats->tot_read_time));
4749 }
4750 static DEVICE_ATTR_RO(read_ns);
4751
4752 /**
4753 * write_cnt_show - write count - number of user calls
4754 * to write(2) that have written data to tape.
4755 * @dev: struct device
4756 * @attr: attribute structure
4757 * @buf: buffer to return formatted data in
4758 */
write_cnt_show(struct device * dev,struct device_attribute * attr,char * buf)4759 static ssize_t write_cnt_show(struct device *dev,
4760 struct device_attribute *attr, char *buf)
4761 {
4762 struct st_modedef *STm = dev_get_drvdata(dev);
4763
4764 return sprintf(buf, "%lld",
4765 (long long)atomic64_read(&STm->tape->stats->write_cnt));
4766 }
4767 static DEVICE_ATTR_RO(write_cnt);
4768
4769 /**
4770 * write_byte_cnt_show - write byte count - raw count of
4771 * bytes written to tape.
4772 * @dev: struct device
4773 * @attr: attribute structure
4774 * @buf: buffer to return formatted data in
4775 */
write_byte_cnt_show(struct device * dev,struct device_attribute * attr,char * buf)4776 static ssize_t write_byte_cnt_show(struct device *dev,
4777 struct device_attribute *attr, char *buf)
4778 {
4779 struct st_modedef *STm = dev_get_drvdata(dev);
4780
4781 return sprintf(buf, "%lld",
4782 (long long)atomic64_read(&STm->tape->stats->write_byte_cnt));
4783 }
4784 static DEVICE_ATTR_RO(write_byte_cnt);
4785
4786 /**
4787 * write_ns_show - write ns - number of nanoseconds waiting on write
4788 * requests to complete.
4789 * @dev: struct device
4790 * @attr: attribute structure
4791 * @buf: buffer to return formatted data in
4792 */
write_ns_show(struct device * dev,struct device_attribute * attr,char * buf)4793 static ssize_t write_ns_show(struct device *dev,
4794 struct device_attribute *attr, char *buf)
4795 {
4796 struct st_modedef *STm = dev_get_drvdata(dev);
4797
4798 return sprintf(buf, "%lld",
4799 (long long)atomic64_read(&STm->tape->stats->tot_write_time));
4800 }
4801 static DEVICE_ATTR_RO(write_ns);
4802
4803 /**
4804 * in_flight_show - number of I/Os currently in flight -
4805 * in most cases this will be either 0 or 1. It may be higher if someone
4806 * has also issued other SCSI commands such as via an ioctl.
4807 * @dev: struct device
4808 * @attr: attribute structure
4809 * @buf: buffer to return formatted data in
4810 */
in_flight_show(struct device * dev,struct device_attribute * attr,char * buf)4811 static ssize_t in_flight_show(struct device *dev,
4812 struct device_attribute *attr, char *buf)
4813 {
4814 struct st_modedef *STm = dev_get_drvdata(dev);
4815
4816 return sprintf(buf, "%lld",
4817 (long long)atomic64_read(&STm->tape->stats->in_flight));
4818 }
4819 static DEVICE_ATTR_RO(in_flight);
4820
4821 /**
4822 * io_ns_show - io wait ns - this is the number of ns spent
4823 * waiting on all I/O to complete. This includes tape movement commands
4824 * such as rewinding, seeking to end of file or tape, it also includes
4825 * read and write. To determine the time spent on tape movement
4826 * subtract the read and write ns from this value.
4827 * @dev: struct device
4828 * @attr: attribute structure
4829 * @buf: buffer to return formatted data in
4830 */
io_ns_show(struct device * dev,struct device_attribute * attr,char * buf)4831 static ssize_t io_ns_show(struct device *dev,
4832 struct device_attribute *attr, char *buf)
4833 {
4834 struct st_modedef *STm = dev_get_drvdata(dev);
4835
4836 return sprintf(buf, "%lld",
4837 (long long)atomic64_read(&STm->tape->stats->tot_io_time));
4838 }
4839 static DEVICE_ATTR_RO(io_ns);
4840
4841 /**
4842 * other_cnt_show - other io count - this is the number of
4843 * I/O requests other than read and write requests.
4844 * Typically these are tape movement requests but will include driver
4845 * tape movement. This includes only requests issued by the st driver.
4846 * @dev: struct device
4847 * @attr: attribute structure
4848 * @buf: buffer to return formatted data in
4849 */
other_cnt_show(struct device * dev,struct device_attribute * attr,char * buf)4850 static ssize_t other_cnt_show(struct device *dev,
4851 struct device_attribute *attr, char *buf)
4852 {
4853 struct st_modedef *STm = dev_get_drvdata(dev);
4854
4855 return sprintf(buf, "%lld",
4856 (long long)atomic64_read(&STm->tape->stats->other_cnt));
4857 }
4858 static DEVICE_ATTR_RO(other_cnt);
4859
4860 /**
4861 * resid_cnt_show - A count of the number of times we get a residual
4862 * count - this should indicate someone issuing reads larger than the
4863 * block size on tape.
4864 * @dev: struct device
4865 * @attr: attribute structure
4866 * @buf: buffer to return formatted data in
4867 */
resid_cnt_show(struct device * dev,struct device_attribute * attr,char * buf)4868 static ssize_t resid_cnt_show(struct device *dev,
4869 struct device_attribute *attr, char *buf)
4870 {
4871 struct st_modedef *STm = dev_get_drvdata(dev);
4872
4873 return sprintf(buf, "%lld",
4874 (long long)atomic64_read(&STm->tape->stats->resid_cnt));
4875 }
4876 static DEVICE_ATTR_RO(resid_cnt);
4877
4878 static struct attribute *st_dev_attrs[] = {
4879 &dev_attr_defined.attr,
4880 &dev_attr_default_blksize.attr,
4881 &dev_attr_default_density.attr,
4882 &dev_attr_default_compression.attr,
4883 &dev_attr_options.attr,
4884 NULL,
4885 };
4886
4887 static struct attribute *st_stats_attrs[] = {
4888 &dev_attr_read_cnt.attr,
4889 &dev_attr_read_byte_cnt.attr,
4890 &dev_attr_read_ns.attr,
4891 &dev_attr_write_cnt.attr,
4892 &dev_attr_write_byte_cnt.attr,
4893 &dev_attr_write_ns.attr,
4894 &dev_attr_in_flight.attr,
4895 &dev_attr_io_ns.attr,
4896 &dev_attr_other_cnt.attr,
4897 &dev_attr_resid_cnt.attr,
4898 NULL,
4899 };
4900
4901 static struct attribute_group stats_group = {
4902 .name = "stats",
4903 .attrs = st_stats_attrs,
4904 };
4905
4906 static struct attribute_group st_group = {
4907 .attrs = st_dev_attrs,
4908 };
4909
4910 static const struct attribute_group *st_dev_groups[] = {
4911 &st_group,
4912 &stats_group,
4913 NULL,
4914 };
4915
4916 /* 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)4917 static int sgl_map_user_pages(struct st_buffer *STbp,
4918 const unsigned int max_pages, unsigned long uaddr,
4919 size_t count, int rw)
4920 {
4921 unsigned long end = (uaddr + count + PAGE_SIZE - 1) >> PAGE_SHIFT;
4922 unsigned long start = uaddr >> PAGE_SHIFT;
4923 const int nr_pages = end - start;
4924 int res, i;
4925 struct page **pages;
4926 struct rq_map_data *mdata = &STbp->map_data;
4927
4928 /* User attempted Overflow! */
4929 if ((uaddr + count) < uaddr)
4930 return -EINVAL;
4931
4932 /* Too big */
4933 if (nr_pages > max_pages)
4934 return -ENOMEM;
4935
4936 /* Hmm? */
4937 if (count == 0)
4938 return 0;
4939
4940 pages = kmalloc_array(max_pages, sizeof(*pages), GFP_KERNEL);
4941 if (pages == NULL)
4942 return -ENOMEM;
4943
4944 /* Try to fault in all of the necessary pages */
4945 /* rw==READ means read from drive, write into memory area */
4946 res = pin_user_pages_fast(uaddr, nr_pages, rw == READ ? FOLL_WRITE : 0,
4947 pages);
4948
4949 /* Errors and no page mapped should return here */
4950 if (res < nr_pages)
4951 goto out_unmap;
4952
4953 for (i=0; i < nr_pages; i++) {
4954 /* FIXME: flush superflous for rw==READ,
4955 * probably wrong function for rw==WRITE
4956 */
4957 flush_dcache_page(pages[i]);
4958 }
4959
4960 mdata->offset = uaddr & ~PAGE_MASK;
4961 STbp->mapped_pages = pages;
4962
4963 return nr_pages;
4964 out_unmap:
4965 if (res > 0) {
4966 unpin_user_pages(pages, res);
4967 res = 0;
4968 }
4969 kfree(pages);
4970 return res;
4971 }
4972
4973
4974 /* And unmap them... */
sgl_unmap_user_pages(struct st_buffer * STbp,const unsigned int nr_pages,int dirtied)4975 static int sgl_unmap_user_pages(struct st_buffer *STbp,
4976 const unsigned int nr_pages, int dirtied)
4977 {
4978 /* FIXME: cache flush missing for rw==READ */
4979 unpin_user_pages_dirty_lock(STbp->mapped_pages, nr_pages, dirtied);
4980
4981 kfree(STbp->mapped_pages);
4982 STbp->mapped_pages = NULL;
4983
4984 return 0;
4985 }
4986