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/major.h>
36 #include <linux/cdrom.h>
37 #include <linux/ioctl.h>
38 #include <linux/fcntl.h>
39 #include <linux/spinlock.h>
40 #include <linux/blkdev.h>
41 #include <linux/moduleparam.h>
42 #include <linux/cdev.h>
43 #include <linux/idr.h>
44 #include <linux/delay.h>
45 #include <linux/mutex.h>
46
47 #include <linux/uaccess.h>
48 #include <asm/dma.h>
49 #include <linux/unaligned.h>
50
51 #include <scsi/scsi.h>
52 #include <scsi/scsi_dbg.h>
53 #include <scsi/scsi_device.h>
54 #include <scsi/scsi_driver.h>
55 #include <scsi/scsi_eh.h>
56 #include <scsi/scsi_host.h>
57 #include <scsi/scsi_ioctl.h>
58 #include <scsi/sg.h>
59
60
61 /* The driver prints some debugging information on the console if DEBUG
62 is defined and non-zero. */
63 #define DEBUG 1
64 #define NO_DEBUG 0
65
66 #define ST_DEB_MSG KERN_NOTICE
67 #if DEBUG
68 /* The message level for the debug messages is currently set to KERN_NOTICE
69 so that people can easily see the messages. Later when the debugging messages
70 in the drivers are more widely classified, this may be changed to KERN_DEBUG. */
71 #define DEB(a) a
72 #define DEBC(a) if (debugging) { a ; }
73 #else
74 #define DEB(a)
75 #define DEBC(a)
76 #endif
77
78 #define ST_KILOBYTE 1024
79
80 #include "st_options.h"
81 #include "st.h"
82
83 static int buffer_kbs;
84 static int max_sg_segs;
85 static int try_direct_io = TRY_DIRECT_IO;
86 static int try_rdio = 1;
87 static int try_wdio = 1;
88 static int debug_flag;
89
90 static const struct class st_sysfs_class;
91 static const struct attribute_group *st_dev_groups[];
92 static const struct attribute_group *st_drv_groups[];
93
94 MODULE_AUTHOR("Kai Makisara");
95 MODULE_DESCRIPTION("SCSI tape (st) driver");
96 MODULE_LICENSE("GPL");
97 MODULE_ALIAS_CHARDEV_MAJOR(SCSI_TAPE_MAJOR);
98 MODULE_ALIAS_SCSI_DEVICE(TYPE_TAPE);
99
100 /* Set 'perm' (4th argument) to 0 to disable module_param's definition
101 * of sysfs parameters (which module_param doesn't yet support).
102 * Sysfs parameters defined explicitly later.
103 */
104 module_param_named(buffer_kbs, buffer_kbs, int, 0);
105 MODULE_PARM_DESC(buffer_kbs, "Default driver buffer size for fixed block mode (KB; 32)");
106 module_param_named(max_sg_segs, max_sg_segs, int, 0);
107 MODULE_PARM_DESC(max_sg_segs, "Maximum number of scatter/gather segments to use (256)");
108 module_param_named(try_direct_io, try_direct_io, int, 0);
109 MODULE_PARM_DESC(try_direct_io, "Try direct I/O between user buffer and tape drive (1)");
110 module_param_named(debug_flag, debug_flag, int, 0);
111 MODULE_PARM_DESC(debug_flag, "Enable DEBUG, same as setting debugging=1");
112
113
114 /* Extra parameters for testing */
115 module_param_named(try_rdio, try_rdio, int, 0);
116 MODULE_PARM_DESC(try_rdio, "Try direct read i/o when possible");
117 module_param_named(try_wdio, try_wdio, int, 0);
118 MODULE_PARM_DESC(try_wdio, "Try direct write i/o when possible");
119
120 #ifndef MODULE
121 static int write_threshold_kbs; /* retained for compatibility */
122 static struct st_dev_parm {
123 char *name;
124 int *val;
125 } parms[] __initdata = {
126 {
127 "buffer_kbs", &buffer_kbs
128 },
129 { /* Retained for compatibility with 2.4 */
130 "write_threshold_kbs", &write_threshold_kbs
131 },
132 {
133 "max_sg_segs", NULL
134 },
135 {
136 "try_direct_io", &try_direct_io
137 },
138 {
139 "debug_flag", &debug_flag
140 }
141 };
142 #endif
143
144 /* Restrict the number of modes so that names for all are assigned */
145 #if ST_NBR_MODES > 16
146 #error "Maximum number of modes is 16"
147 #endif
148 /* Bit reversed order to get same names for same minors with all
149 mode counts */
150 static const char *st_formats[] = {
151 "", "r", "k", "s", "l", "t", "o", "u",
152 "m", "v", "p", "x", "a", "y", "q", "z"};
153
154 /* The default definitions have been moved to st_options.h */
155
156 #define ST_FIXED_BUFFER_SIZE (ST_FIXED_BUFFER_BLOCKS * ST_KILOBYTE)
157
158 /* The buffer size should fit into the 24 bits for length in the
159 6-byte SCSI read and write commands. */
160 #if ST_FIXED_BUFFER_SIZE >= (2 << 24 - 1)
161 #error "Buffer size should not exceed (2 << 24 - 1) bytes!"
162 #endif
163
164 static int debugging = DEBUG;
165
166 #define MAX_RETRIES 0
167 #define MAX_WRITE_RETRIES 0
168 #define MAX_READY_RETRIES 0
169 #define NO_TAPE NOT_READY
170
171 #define ST_TIMEOUT (900 * HZ)
172 #define ST_LONG_TIMEOUT (14000 * HZ)
173
174 /* Remove mode bits and auto-rewind bit (7) */
175 #define TAPE_NR(x) ( ((iminor(x) & ~255) >> (ST_NBR_MODE_BITS + 1)) | \
176 (iminor(x) & ((1 << ST_MODE_SHIFT)-1)))
177 #define TAPE_MODE(x) ((iminor(x) & ST_MODE_MASK) >> ST_MODE_SHIFT)
178
179 /* Construct the minor number from the device (d), mode (m), and non-rewind (n) data */
180 #define TAPE_MINOR(d, m, n) (((d & ~(255 >> (ST_NBR_MODE_BITS + 1))) << (ST_NBR_MODE_BITS + 1)) | \
181 (d & (255 >> (ST_NBR_MODE_BITS + 1))) | (m << ST_MODE_SHIFT) | ((n != 0) << 7) )
182
183 /* Internal ioctl to set both density (uppermost 8 bits) and blocksize (lower
184 24 bits) */
185 #define SET_DENS_AND_BLK 0x10001
186
187 static int st_fixed_buffer_size = ST_FIXED_BUFFER_SIZE;
188 static int st_max_sg_segs = ST_MAX_SG;
189
190 static int modes_defined;
191
192 static int enlarge_buffer(struct st_buffer *, int);
193 static void clear_buffer(struct st_buffer *);
194 static void normalize_buffer(struct st_buffer *);
195 static int append_to_buffer(const char __user *, struct st_buffer *, int);
196 static int from_buffer(struct st_buffer *, char __user *, int);
197 static void move_buffer_data(struct st_buffer *, int);
198
199 static int sgl_map_user_pages(struct st_buffer *, const unsigned int,
200 unsigned long, size_t, int);
201 static int sgl_unmap_user_pages(struct st_buffer *, const unsigned int, int);
202
203 static int st_probe(struct device *);
204 static int st_remove(struct device *);
205
206 static struct scsi_driver st_template = {
207 .gendrv = {
208 .name = "st",
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
312 #define st_printk(prefix, t, fmt, a...) \
313 sdev_prefix_printk(prefix, (t)->device, (t)->name, fmt, ##a)
314 #ifdef DEBUG
315 #define DEBC_printk(t, fmt, a...) \
316 if (debugging) { st_printk(ST_DEB_MSG, t, fmt, ##a ); }
317 #else
318 #define DEBC_printk(t, fmt, a...)
319 #endif
320
st_analyze_sense(struct st_request * SRpnt,struct st_cmdstatus * s)321 static void st_analyze_sense(struct st_request *SRpnt, struct st_cmdstatus *s)
322 {
323 const u8 *ucp;
324 const u8 *sense = SRpnt->sense;
325
326 s->have_sense = scsi_normalize_sense(SRpnt->sense,
327 SCSI_SENSE_BUFFERSIZE, &s->sense_hdr);
328 s->flags = 0;
329
330 if (s->have_sense) {
331 s->deferred = 0;
332 s->remainder_valid =
333 scsi_get_sense_info_fld(sense, SCSI_SENSE_BUFFERSIZE, &s->uremainder64);
334 switch (sense[0] & 0x7f) {
335 case 0x71:
336 s->deferred = 1;
337 fallthrough;
338 case 0x70:
339 s->fixed_format = 1;
340 s->flags = sense[2] & 0xe0;
341 break;
342 case 0x73:
343 s->deferred = 1;
344 fallthrough;
345 case 0x72:
346 s->fixed_format = 0;
347 ucp = scsi_sense_desc_find(sense, SCSI_SENSE_BUFFERSIZE, 4);
348 s->flags = ucp ? (ucp[3] & 0xe0) : 0;
349 break;
350 }
351 }
352 }
353
354
355 /* Convert the result to success code */
st_chk_result(struct scsi_tape * STp,struct st_request * SRpnt)356 static int st_chk_result(struct scsi_tape *STp, struct st_request * SRpnt)
357 {
358 int result = SRpnt->result;
359 u8 scode;
360 DEB(const char *stp;)
361 char *name = STp->name;
362 struct st_cmdstatus *cmdstatp;
363
364 if (!result)
365 return 0;
366
367 cmdstatp = &STp->buffer->cmdstat;
368 st_analyze_sense(SRpnt, cmdstatp);
369
370 if (cmdstatp->have_sense)
371 scode = STp->buffer->cmdstat.sense_hdr.sense_key;
372 else
373 scode = 0;
374
375 DEB(
376 if (debugging) {
377 st_printk(ST_DEB_MSG, STp,
378 "Error: %x, cmd: %x %x %x %x %x %x\n", result,
379 SRpnt->cmd[0], SRpnt->cmd[1], SRpnt->cmd[2],
380 SRpnt->cmd[3], SRpnt->cmd[4], SRpnt->cmd[5]);
381 if (cmdstatp->have_sense)
382 __scsi_print_sense(STp->device, name,
383 SRpnt->sense, SCSI_SENSE_BUFFERSIZE);
384 } ) /* end DEB */
385 if (!debugging) { /* Abnormal conditions for tape */
386 if (!cmdstatp->have_sense)
387 st_printk(KERN_WARNING, STp,
388 "Error %x (driver bt 0, host bt 0x%x).\n",
389 result, host_byte(result));
390 else if (cmdstatp->have_sense &&
391 scode != NO_SENSE &&
392 scode != RECOVERED_ERROR &&
393 /* scode != UNIT_ATTENTION && */
394 scode != BLANK_CHECK &&
395 scode != VOLUME_OVERFLOW &&
396 SRpnt->cmd[0] != MODE_SENSE &&
397 SRpnt->cmd[0] != TEST_UNIT_READY) {
398
399 __scsi_print_sense(STp->device, name,
400 SRpnt->sense, SCSI_SENSE_BUFFERSIZE);
401 }
402 }
403
404 if (cmdstatp->fixed_format &&
405 STp->cln_mode >= EXTENDED_SENSE_START) { /* Only fixed format sense */
406 if (STp->cln_sense_value)
407 STp->cleaning_req |= ((SRpnt->sense[STp->cln_mode] &
408 STp->cln_sense_mask) == STp->cln_sense_value);
409 else
410 STp->cleaning_req |= ((SRpnt->sense[STp->cln_mode] &
411 STp->cln_sense_mask) != 0);
412 }
413 if (cmdstatp->have_sense &&
414 cmdstatp->sense_hdr.asc == 0 && cmdstatp->sense_hdr.ascq == 0x17)
415 STp->cleaning_req = 1; /* ASC and ASCQ => cleaning requested */
416 if (cmdstatp->have_sense && scode == UNIT_ATTENTION && cmdstatp->sense_hdr.asc == 0x29)
417 STp->pos_unknown = 1; /* ASC => power on / reset */
418
419 STp->pos_unknown |= STp->device->was_reset;
420
421 if (cmdstatp->have_sense &&
422 scode == RECOVERED_ERROR
423 #if ST_RECOVERED_WRITE_FATAL
424 && SRpnt->cmd[0] != WRITE_6
425 && SRpnt->cmd[0] != WRITE_FILEMARKS
426 #endif
427 ) {
428 STp->recover_count++;
429 STp->recover_reg++;
430
431 DEB(
432 if (debugging) {
433 if (SRpnt->cmd[0] == READ_6)
434 stp = "read";
435 else if (SRpnt->cmd[0] == WRITE_6)
436 stp = "write";
437 else
438 stp = "ioctl";
439 st_printk(ST_DEB_MSG, STp,
440 "Recovered %s error (%d).\n",
441 stp, STp->recover_count);
442 } ) /* end DEB */
443
444 if (cmdstatp->flags == 0)
445 return 0;
446 }
447 return (-EIO);
448 }
449
st_allocate_request(struct scsi_tape * stp)450 static struct st_request *st_allocate_request(struct scsi_tape *stp)
451 {
452 struct st_request *streq;
453
454 streq = kzalloc(sizeof(*streq), GFP_KERNEL);
455 if (streq)
456 streq->stp = stp;
457 else {
458 st_printk(KERN_ERR, stp,
459 "Can't get SCSI request.\n");
460 if (signal_pending(current))
461 stp->buffer->syscall_result = -EINTR;
462 else
463 stp->buffer->syscall_result = -EBUSY;
464 }
465
466 return streq;
467 }
468
st_release_request(struct st_request * streq)469 static void st_release_request(struct st_request *streq)
470 {
471 kfree(streq);
472 }
473
st_do_stats(struct scsi_tape * STp,struct request * req)474 static void st_do_stats(struct scsi_tape *STp, struct request *req)
475 {
476 struct scsi_cmnd *scmd = blk_mq_rq_to_pdu(req);
477 ktime_t now;
478
479 now = ktime_get();
480 if (scmd->cmnd[0] == WRITE_6) {
481 now = ktime_sub(now, STp->stats->write_time);
482 atomic64_add(ktime_to_ns(now), &STp->stats->tot_write_time);
483 atomic64_add(ktime_to_ns(now), &STp->stats->tot_io_time);
484 atomic64_inc(&STp->stats->write_cnt);
485 if (scmd->result) {
486 atomic64_add(atomic_read(&STp->stats->last_write_size)
487 - STp->buffer->cmdstat.residual,
488 &STp->stats->write_byte_cnt);
489 if (STp->buffer->cmdstat.residual > 0)
490 atomic64_inc(&STp->stats->resid_cnt);
491 } else
492 atomic64_add(atomic_read(&STp->stats->last_write_size),
493 &STp->stats->write_byte_cnt);
494 } else if (scmd->cmnd[0] == READ_6) {
495 now = ktime_sub(now, STp->stats->read_time);
496 atomic64_add(ktime_to_ns(now), &STp->stats->tot_read_time);
497 atomic64_add(ktime_to_ns(now), &STp->stats->tot_io_time);
498 atomic64_inc(&STp->stats->read_cnt);
499 if (scmd->result) {
500 atomic64_add(atomic_read(&STp->stats->last_read_size)
501 - STp->buffer->cmdstat.residual,
502 &STp->stats->read_byte_cnt);
503 if (STp->buffer->cmdstat.residual > 0)
504 atomic64_inc(&STp->stats->resid_cnt);
505 } else
506 atomic64_add(atomic_read(&STp->stats->last_read_size),
507 &STp->stats->read_byte_cnt);
508 } else {
509 now = ktime_sub(now, STp->stats->other_time);
510 atomic64_add(ktime_to_ns(now), &STp->stats->tot_io_time);
511 atomic64_inc(&STp->stats->other_cnt);
512 }
513 atomic64_dec(&STp->stats->in_flight);
514 }
515
st_scsi_execute_end(struct request * req,blk_status_t status)516 static enum rq_end_io_ret st_scsi_execute_end(struct request *req,
517 blk_status_t status)
518 {
519 struct scsi_cmnd *scmd = blk_mq_rq_to_pdu(req);
520 struct st_request *SRpnt = req->end_io_data;
521 struct scsi_tape *STp = SRpnt->stp;
522 struct bio *tmp;
523
524 STp->buffer->cmdstat.midlevel_result = SRpnt->result = scmd->result;
525 STp->buffer->cmdstat.residual = scmd->resid_len;
526
527 st_do_stats(STp, req);
528
529 tmp = SRpnt->bio;
530 if (scmd->sense_len)
531 memcpy(SRpnt->sense, scmd->sense_buffer, SCSI_SENSE_BUFFERSIZE);
532 if (SRpnt->waiting)
533 complete(SRpnt->waiting);
534
535 blk_rq_unmap_user(tmp);
536 blk_mq_free_request(req);
537 return RQ_END_IO_NONE;
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 rq_map_data *mdata = &SRpnt->stp->buffer->map_data;
546 int err = 0;
547 struct scsi_tape *STp = SRpnt->stp;
548 struct scsi_cmnd *scmd;
549
550 req = scsi_alloc_request(SRpnt->stp->device->request_queue,
551 data_direction == DMA_TO_DEVICE ?
552 REQ_OP_DRV_OUT : REQ_OP_DRV_IN, 0);
553 if (IS_ERR(req))
554 return PTR_ERR(req);
555 scmd = blk_mq_rq_to_pdu(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_mq_free_request(req);
565 return err;
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 scmd->cmd_len = COMMAND_SIZE(cmd[0]);
582 memcpy(scmd->cmnd, cmd, scmd->cmd_len);
583 req->timeout = timeout;
584 scmd->allowed = retries;
585 req->end_io = st_scsi_execute_end;
586 req->end_io_data = SRpnt;
587
588 blk_execute_rq_nowait(req, true);
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 if (STp->ready != ST_READY)
838 return 0;
839
840 /*
841 * If there was a bus reset, block further access
842 * to this device.
843 */
844 if (STp->pos_unknown)
845 return (-EIO);
846
847 STps = &(STp->ps[STp->partition]);
848 if (STps->rw == ST_WRITING) /* Writing */
849 return st_flush_write_buffer(STp);
850
851 if (STp->block_size == 0)
852 return 0;
853
854 backspace = ((STp->buffer)->buffer_bytes +
855 (STp->buffer)->read_pointer) / STp->block_size -
856 ((STp->buffer)->read_pointer + STp->block_size - 1) /
857 STp->block_size;
858 (STp->buffer)->buffer_bytes = 0;
859 (STp->buffer)->read_pointer = 0;
860 result = 0;
861 if (!seek_next) {
862 if (STps->eof == ST_FM_HIT) {
863 result = cross_eof(STp, 0); /* Back over the EOF hit */
864 if (!result)
865 STps->eof = ST_NOEOF;
866 else {
867 if (STps->drv_file >= 0)
868 STps->drv_file++;
869 STps->drv_block = 0;
870 }
871 }
872 if (!result && backspace > 0)
873 result = st_int_ioctl(STp, MTBSR, backspace);
874 } else if (STps->eof == ST_FM_HIT) {
875 if (STps->drv_file >= 0)
876 STps->drv_file++;
877 STps->drv_block = 0;
878 STps->eof = ST_NOEOF;
879 }
880 return result;
881
882 }
883
884 /* Set the mode parameters */
set_mode_densblk(struct scsi_tape * STp,struct st_modedef * STm)885 static int set_mode_densblk(struct scsi_tape * STp, struct st_modedef * STm)
886 {
887 int set_it = 0;
888 unsigned long arg;
889
890 if (!STp->density_changed &&
891 STm->default_density >= 0 &&
892 STm->default_density != STp->density) {
893 arg = STm->default_density;
894 set_it = 1;
895 } else
896 arg = STp->density;
897 arg <<= MT_ST_DENSITY_SHIFT;
898 if (!STp->blksize_changed &&
899 STm->default_blksize >= 0 &&
900 STm->default_blksize != STp->block_size) {
901 arg |= STm->default_blksize;
902 set_it = 1;
903 } else
904 arg |= STp->block_size;
905 if (set_it &&
906 st_int_ioctl(STp, SET_DENS_AND_BLK, arg)) {
907 st_printk(KERN_WARNING, STp,
908 "Can't set default block size to %d bytes "
909 "and density %x.\n",
910 STm->default_blksize, STm->default_density);
911 if (modes_defined)
912 return (-EINVAL);
913 }
914 return 0;
915 }
916
917
918 /* Lock or unlock the drive door. Don't use when st_request allocated. */
do_door_lock(struct scsi_tape * STp,int do_lock)919 static int do_door_lock(struct scsi_tape * STp, int do_lock)
920 {
921 int retval;
922
923 DEBC_printk(STp, "%socking drive door.\n", do_lock ? "L" : "Unl");
924
925 retval = scsi_set_medium_removal(STp->device,
926 do_lock ? SCSI_REMOVAL_PREVENT : SCSI_REMOVAL_ALLOW);
927 if (!retval)
928 STp->door_locked = do_lock ? ST_LOCKED_EXPLICIT : ST_UNLOCKED;
929 else
930 STp->door_locked = ST_LOCK_FAILS;
931 return retval;
932 }
933
934
935 /* Set the internal state after reset */
reset_state(struct scsi_tape * STp)936 static void reset_state(struct scsi_tape *STp)
937 {
938 int i;
939 struct st_partstat *STps;
940
941 STp->pos_unknown = 0;
942 for (i = 0; i < ST_NBR_PARTITIONS; i++) {
943 STps = &(STp->ps[i]);
944 STps->rw = ST_IDLE;
945 STps->eof = ST_NOEOF;
946 STps->at_sm = 0;
947 STps->last_block_valid = 0;
948 STps->drv_block = -1;
949 STps->drv_file = -1;
950 }
951 if (STp->can_partitions) {
952 STp->partition = find_partition(STp);
953 if (STp->partition < 0)
954 STp->partition = 0;
955 STp->new_partition = STp->partition;
956 }
957 }
958
959 /* Test if the drive is ready. Returns either one of the codes below or a negative system
960 error code. */
961 #define CHKRES_READY 0
962 #define CHKRES_NEW_SESSION 1
963 #define CHKRES_NOT_READY 2
964 #define CHKRES_NO_TAPE 3
965
966 #define MAX_ATTENTIONS 10
967
test_ready(struct scsi_tape * STp,int do_wait)968 static int test_ready(struct scsi_tape *STp, int do_wait)
969 {
970 int attentions, waits, max_wait, scode;
971 int retval = CHKRES_READY, new_session = 0;
972 unsigned char cmd[MAX_COMMAND_SIZE];
973 struct st_request *SRpnt = NULL;
974 struct st_cmdstatus *cmdstatp = &STp->buffer->cmdstat;
975
976 max_wait = do_wait ? ST_BLOCK_SECONDS : 0;
977
978 for (attentions=waits=0; ; ) {
979 memset((void *) &cmd[0], 0, MAX_COMMAND_SIZE);
980 cmd[0] = TEST_UNIT_READY;
981 SRpnt = st_do_scsi(SRpnt, STp, cmd, 0, DMA_NONE,
982 STp->long_timeout, MAX_READY_RETRIES, 1);
983
984 if (!SRpnt) {
985 retval = (STp->buffer)->syscall_result;
986 break;
987 }
988
989 if (cmdstatp->have_sense) {
990
991 scode = cmdstatp->sense_hdr.sense_key;
992
993 if (scode == UNIT_ATTENTION) { /* New media? */
994 if (cmdstatp->sense_hdr.asc == 0x28) { /* New media */
995 new_session = 1;
996 DEBC_printk(STp, "New tape session.");
997 }
998 if (attentions < MAX_ATTENTIONS) {
999 attentions++;
1000 continue;
1001 }
1002 else {
1003 retval = (-EIO);
1004 break;
1005 }
1006 }
1007
1008 if (scode == NOT_READY) {
1009 if (waits < max_wait) {
1010 if (msleep_interruptible(1000)) {
1011 retval = (-EINTR);
1012 break;
1013 }
1014 waits++;
1015 continue;
1016 }
1017 else {
1018 if ((STp->device)->scsi_level >= SCSI_2 &&
1019 cmdstatp->sense_hdr.asc == 0x3a) /* Check ASC */
1020 retval = CHKRES_NO_TAPE;
1021 else
1022 retval = CHKRES_NOT_READY;
1023 break;
1024 }
1025 }
1026 }
1027
1028 retval = (STp->buffer)->syscall_result;
1029 if (!retval)
1030 retval = new_session ? CHKRES_NEW_SESSION : CHKRES_READY;
1031 break;
1032 }
1033 if (STp->first_tur) {
1034 /* Don't set pos_unknown right after device recognition */
1035 STp->pos_unknown = 0;
1036 STp->first_tur = 0;
1037 }
1038
1039 if (SRpnt != NULL)
1040 st_release_request(SRpnt);
1041 return retval;
1042 }
1043
1044
1045 /* See if the drive is ready and gather information about the tape. Return values:
1046 < 0 negative error code from errno.h
1047 0 drive ready
1048 1 drive not ready (possibly no tape)
1049 */
check_tape(struct scsi_tape * STp,struct file * filp)1050 static int check_tape(struct scsi_tape *STp, struct file *filp)
1051 {
1052 int i, retval, new_session = 0, do_wait;
1053 unsigned char cmd[MAX_COMMAND_SIZE], saved_cleaning;
1054 unsigned short st_flags = filp->f_flags;
1055 struct st_request *SRpnt = NULL;
1056 struct st_modedef *STm;
1057 struct st_partstat *STps;
1058 struct inode *inode = file_inode(filp);
1059 int mode = TAPE_MODE(inode);
1060
1061 STp->ready = ST_READY;
1062
1063 if (mode != STp->current_mode) {
1064 DEBC_printk(STp, "Mode change from %d to %d.\n",
1065 STp->current_mode, mode);
1066 new_session = 1;
1067 STp->current_mode = mode;
1068 }
1069 STm = &(STp->modes[STp->current_mode]);
1070
1071 saved_cleaning = STp->cleaning_req;
1072 STp->cleaning_req = 0;
1073
1074 do_wait = ((filp->f_flags & O_NONBLOCK) == 0);
1075 retval = test_ready(STp, do_wait);
1076
1077 if (retval < 0)
1078 goto err_out;
1079
1080 if (retval == CHKRES_NEW_SESSION) {
1081 STp->pos_unknown = 0;
1082 STp->partition = STp->new_partition = 0;
1083 if (STp->can_partitions)
1084 STp->nbr_partitions = 1; /* This guess will be updated later
1085 if necessary */
1086 for (i = 0; i < ST_NBR_PARTITIONS; i++) {
1087 STps = &(STp->ps[i]);
1088 STps->rw = ST_IDLE;
1089 STps->eof = ST_NOEOF;
1090 STps->at_sm = 0;
1091 STps->last_block_valid = 0;
1092 STps->drv_block = 0;
1093 STps->drv_file = 0;
1094 }
1095 new_session = 1;
1096 }
1097 else {
1098 STp->cleaning_req |= saved_cleaning;
1099
1100 if (retval == CHKRES_NOT_READY || retval == CHKRES_NO_TAPE) {
1101 if (retval == CHKRES_NO_TAPE)
1102 STp->ready = ST_NO_TAPE;
1103 else
1104 STp->ready = ST_NOT_READY;
1105
1106 STp->density = 0; /* Clear the erroneous "residue" */
1107 STp->write_prot = 0;
1108 STp->block_size = 0;
1109 STp->ps[0].drv_file = STp->ps[0].drv_block = (-1);
1110 STp->partition = STp->new_partition = 0;
1111 STp->door_locked = ST_UNLOCKED;
1112 return CHKRES_NOT_READY;
1113 }
1114 }
1115
1116 if (STp->omit_blklims)
1117 STp->min_block = STp->max_block = (-1);
1118 else {
1119 memset((void *) &cmd[0], 0, MAX_COMMAND_SIZE);
1120 cmd[0] = READ_BLOCK_LIMITS;
1121
1122 SRpnt = st_do_scsi(SRpnt, STp, cmd, 6, DMA_FROM_DEVICE,
1123 STp->device->request_queue->rq_timeout,
1124 MAX_READY_RETRIES, 1);
1125 if (!SRpnt) {
1126 retval = (STp->buffer)->syscall_result;
1127 goto err_out;
1128 }
1129
1130 if (!SRpnt->result && !STp->buffer->cmdstat.have_sense) {
1131 STp->max_block = ((STp->buffer)->b_data[1] << 16) |
1132 ((STp->buffer)->b_data[2] << 8) | (STp->buffer)->b_data[3];
1133 STp->min_block = ((STp->buffer)->b_data[4] << 8) |
1134 (STp->buffer)->b_data[5];
1135 if ( DEB( debugging || ) !STp->inited)
1136 st_printk(KERN_INFO, STp,
1137 "Block limits %d - %d bytes.\n",
1138 STp->min_block, STp->max_block);
1139 } else {
1140 STp->min_block = STp->max_block = (-1);
1141 DEBC_printk(STp, "Can't read block limits.\n");
1142 }
1143 }
1144
1145 memset((void *) &cmd[0], 0, MAX_COMMAND_SIZE);
1146 cmd[0] = MODE_SENSE;
1147 cmd[4] = 12;
1148
1149 SRpnt = st_do_scsi(SRpnt, STp, cmd, 12, DMA_FROM_DEVICE,
1150 STp->device->request_queue->rq_timeout,
1151 MAX_READY_RETRIES, 1);
1152 if (!SRpnt) {
1153 retval = (STp->buffer)->syscall_result;
1154 goto err_out;
1155 }
1156
1157 if ((STp->buffer)->syscall_result != 0) {
1158 DEBC_printk(STp, "No Mode Sense.\n");
1159 STp->block_size = ST_DEFAULT_BLOCK; /* Educated guess (?) */
1160 (STp->buffer)->syscall_result = 0; /* Prevent error propagation */
1161 STp->drv_write_prot = 0;
1162 } else {
1163 DEBC_printk(STp,"Mode sense. Length %d, "
1164 "medium %x, WBS %x, BLL %d\n",
1165 (STp->buffer)->b_data[0],
1166 (STp->buffer)->b_data[1],
1167 (STp->buffer)->b_data[2],
1168 (STp->buffer)->b_data[3]);
1169
1170 if ((STp->buffer)->b_data[3] >= 8) {
1171 STp->drv_buffer = ((STp->buffer)->b_data[2] >> 4) & 7;
1172 STp->density = (STp->buffer)->b_data[4];
1173 STp->block_size = (STp->buffer)->b_data[9] * 65536 +
1174 (STp->buffer)->b_data[10] * 256 + (STp->buffer)->b_data[11];
1175 DEBC_printk(STp, "Density %x, tape length: %x, "
1176 "drv buffer: %d\n",
1177 STp->density,
1178 (STp->buffer)->b_data[5] * 65536 +
1179 (STp->buffer)->b_data[6] * 256 +
1180 (STp->buffer)->b_data[7],
1181 STp->drv_buffer);
1182 }
1183 STp->drv_write_prot = ((STp->buffer)->b_data[2] & 0x80) != 0;
1184 if (!STp->drv_buffer && STp->immediate_filemark) {
1185 st_printk(KERN_WARNING, STp,
1186 "non-buffered tape: disabling "
1187 "writing immediate filemarks\n");
1188 STp->immediate_filemark = 0;
1189 }
1190 }
1191 st_release_request(SRpnt);
1192 SRpnt = NULL;
1193 STp->inited = 1;
1194
1195 if (STp->block_size > 0)
1196 (STp->buffer)->buffer_blocks =
1197 (STp->buffer)->buffer_size / STp->block_size;
1198 else
1199 (STp->buffer)->buffer_blocks = 1;
1200 (STp->buffer)->buffer_bytes = (STp->buffer)->read_pointer = 0;
1201
1202 DEBC_printk(STp, "Block size: %d, buffer size: %d (%d blocks).\n",
1203 STp->block_size, (STp->buffer)->buffer_size,
1204 (STp->buffer)->buffer_blocks);
1205
1206 if (STp->drv_write_prot) {
1207 STp->write_prot = 1;
1208
1209 DEBC_printk(STp, "Write protected\n");
1210
1211 if (do_wait &&
1212 ((st_flags & O_ACCMODE) == O_WRONLY ||
1213 (st_flags & O_ACCMODE) == O_RDWR)) {
1214 retval = (-EROFS);
1215 goto err_out;
1216 }
1217 }
1218
1219 if (STp->can_partitions && STp->nbr_partitions < 1) {
1220 /* This code is reached when the device is opened for the first time
1221 after the driver has been initialized with tape in the drive and the
1222 partition support has been enabled. */
1223 DEBC_printk(STp, "Updating partition number in status.\n");
1224 if ((STp->partition = find_partition(STp)) < 0) {
1225 retval = STp->partition;
1226 goto err_out;
1227 }
1228 STp->new_partition = STp->partition;
1229 STp->nbr_partitions = 1; /* This guess will be updated when necessary */
1230 }
1231
1232 if (new_session) { /* Change the drive parameters for the new mode */
1233 STp->density_changed = STp->blksize_changed = 0;
1234 STp->compression_changed = 0;
1235 if (!(STm->defaults_for_writes) &&
1236 (retval = set_mode_densblk(STp, STm)) < 0)
1237 goto err_out;
1238
1239 if (STp->default_drvbuffer != 0xff) {
1240 if (st_int_ioctl(STp, MTSETDRVBUFFER, STp->default_drvbuffer))
1241 st_printk(KERN_WARNING, STp,
1242 "Can't set default drive "
1243 "buffering to %d.\n",
1244 STp->default_drvbuffer);
1245 }
1246 }
1247
1248 return CHKRES_READY;
1249
1250 err_out:
1251 return retval;
1252 }
1253
1254
1255 /* Open the device. Needs to take the BKL only because of incrementing the SCSI host
1256 module count. */
st_open(struct inode * inode,struct file * filp)1257 static int st_open(struct inode *inode, struct file *filp)
1258 {
1259 int i, retval = (-EIO);
1260 int resumed = 0;
1261 struct scsi_tape *STp;
1262 struct st_partstat *STps;
1263 int dev = TAPE_NR(inode);
1264
1265 /*
1266 * We really want to do nonseekable_open(inode, filp); here, but some
1267 * versions of tar incorrectly call lseek on tapes and bail out if that
1268 * fails. So we disallow pread() and pwrite(), but permit lseeks.
1269 */
1270 filp->f_mode &= ~(FMODE_PREAD | FMODE_PWRITE);
1271
1272 if (!(STp = scsi_tape_get(dev))) {
1273 return -ENXIO;
1274 }
1275
1276 filp->private_data = STp;
1277
1278 spin_lock(&st_use_lock);
1279 if (STp->in_use) {
1280 spin_unlock(&st_use_lock);
1281 DEBC_printk(STp, "Device already in use.\n");
1282 scsi_tape_put(STp);
1283 return (-EBUSY);
1284 }
1285
1286 STp->in_use = 1;
1287 spin_unlock(&st_use_lock);
1288 STp->rew_at_close = STp->autorew_dev = (iminor(inode) & 0x80) == 0;
1289
1290 if (scsi_autopm_get_device(STp->device) < 0) {
1291 retval = -EIO;
1292 goto err_out;
1293 }
1294 resumed = 1;
1295 if (!scsi_block_when_processing_errors(STp->device)) {
1296 retval = (-ENXIO);
1297 goto err_out;
1298 }
1299
1300 /* See that we have at least a one page buffer available */
1301 if (!enlarge_buffer(STp->buffer, PAGE_SIZE)) {
1302 st_printk(KERN_WARNING, STp,
1303 "Can't allocate one page tape buffer.\n");
1304 retval = (-EOVERFLOW);
1305 goto err_out;
1306 }
1307
1308 (STp->buffer)->cleared = 0;
1309 (STp->buffer)->writing = 0;
1310 (STp->buffer)->syscall_result = 0;
1311
1312 STp->write_prot = ((filp->f_flags & O_ACCMODE) == O_RDONLY);
1313
1314 STp->dirty = 0;
1315 for (i = 0; i < ST_NBR_PARTITIONS; i++) {
1316 STps = &(STp->ps[i]);
1317 STps->rw = ST_IDLE;
1318 }
1319 STp->try_dio_now = STp->try_dio;
1320 STp->recover_count = 0;
1321 DEB( STp->nbr_waits = STp->nbr_finished = 0;
1322 STp->nbr_requests = STp->nbr_dio = STp->nbr_pages = 0; )
1323
1324 retval = check_tape(STp, filp);
1325 if (retval < 0)
1326 goto err_out;
1327 if ((filp->f_flags & O_NONBLOCK) == 0 &&
1328 retval != CHKRES_READY) {
1329 if (STp->ready == NO_TAPE)
1330 retval = (-ENOMEDIUM);
1331 else
1332 retval = (-EIO);
1333 goto err_out;
1334 }
1335 return 0;
1336
1337 err_out:
1338 normalize_buffer(STp->buffer);
1339 spin_lock(&st_use_lock);
1340 STp->in_use = 0;
1341 spin_unlock(&st_use_lock);
1342 if (resumed)
1343 scsi_autopm_put_device(STp->device);
1344 scsi_tape_put(STp);
1345 return retval;
1346
1347 }
1348
1349
1350 /* Flush the tape buffer before close */
st_flush(struct file * filp,fl_owner_t id)1351 static int st_flush(struct file *filp, fl_owner_t id)
1352 {
1353 int result = 0, result2;
1354 unsigned char cmd[MAX_COMMAND_SIZE];
1355 struct st_request *SRpnt;
1356 struct scsi_tape *STp = filp->private_data;
1357 struct st_modedef *STm = &(STp->modes[STp->current_mode]);
1358 struct st_partstat *STps = &(STp->ps[STp->partition]);
1359
1360 if (file_count(filp) > 1)
1361 return 0;
1362
1363 if (STps->rw == ST_WRITING && !STp->pos_unknown) {
1364 result = st_flush_write_buffer(STp);
1365 if (result != 0 && result != (-ENOSPC))
1366 goto out;
1367 }
1368
1369 if (STp->can_partitions &&
1370 (result2 = switch_partition(STp)) < 0) {
1371 DEBC_printk(STp, "switch_partition at close failed.\n");
1372 if (result == 0)
1373 result = result2;
1374 goto out;
1375 }
1376
1377 DEBC( if (STp->nbr_requests)
1378 st_printk(KERN_DEBUG, STp,
1379 "Number of r/w requests %d, dio used in %d, "
1380 "pages %d.\n", STp->nbr_requests, STp->nbr_dio,
1381 STp->nbr_pages));
1382
1383 if (STps->rw == ST_WRITING && !STp->pos_unknown) {
1384 struct st_cmdstatus *cmdstatp = &STp->buffer->cmdstat;
1385
1386 #if DEBUG
1387 DEBC_printk(STp, "Async write waits %d, finished %d.\n",
1388 STp->nbr_waits, STp->nbr_finished);
1389 #endif
1390 memset(cmd, 0, MAX_COMMAND_SIZE);
1391 cmd[0] = WRITE_FILEMARKS;
1392 if (STp->immediate_filemark)
1393 cmd[1] = 1;
1394 cmd[4] = 1 + STp->two_fm;
1395
1396 SRpnt = st_do_scsi(NULL, STp, cmd, 0, DMA_NONE,
1397 STp->device->request_queue->rq_timeout,
1398 MAX_WRITE_RETRIES, 1);
1399 if (!SRpnt) {
1400 result = (STp->buffer)->syscall_result;
1401 goto out;
1402 }
1403
1404 if (STp->buffer->syscall_result == 0 ||
1405 (cmdstatp->have_sense && !cmdstatp->deferred &&
1406 (cmdstatp->flags & SENSE_EOM) &&
1407 (cmdstatp->sense_hdr.sense_key == NO_SENSE ||
1408 cmdstatp->sense_hdr.sense_key == RECOVERED_ERROR) &&
1409 (!cmdstatp->remainder_valid || cmdstatp->uremainder64 == 0))) {
1410 /* Write successful at EOM */
1411 st_release_request(SRpnt);
1412 SRpnt = NULL;
1413 if (STps->drv_file >= 0)
1414 STps->drv_file++;
1415 STps->drv_block = 0;
1416 if (STp->two_fm)
1417 cross_eof(STp, 0);
1418 STps->eof = ST_FM;
1419 }
1420 else { /* Write error */
1421 st_release_request(SRpnt);
1422 SRpnt = NULL;
1423 st_printk(KERN_ERR, STp,
1424 "Error on write filemark.\n");
1425 if (result == 0)
1426 result = (-EIO);
1427 }
1428
1429 DEBC_printk(STp, "Buffer flushed, %d EOF(s) written\n", cmd[4]);
1430 } else if (!STp->rew_at_close) {
1431 STps = &(STp->ps[STp->partition]);
1432 if (!STm->sysv || STps->rw != ST_READING) {
1433 if (STp->can_bsr)
1434 result = flush_buffer(STp, 0);
1435 else if (STps->eof == ST_FM_HIT) {
1436 result = cross_eof(STp, 0);
1437 if (result) {
1438 if (STps->drv_file >= 0)
1439 STps->drv_file++;
1440 STps->drv_block = 0;
1441 STps->eof = ST_FM;
1442 } else
1443 STps->eof = ST_NOEOF;
1444 }
1445 } else if ((STps->eof == ST_NOEOF &&
1446 !(result = cross_eof(STp, 1))) ||
1447 STps->eof == ST_FM_HIT) {
1448 if (STps->drv_file >= 0)
1449 STps->drv_file++;
1450 STps->drv_block = 0;
1451 STps->eof = ST_FM;
1452 }
1453 }
1454
1455 out:
1456 if (STp->rew_at_close) {
1457 result2 = st_int_ioctl(STp, MTREW, 1);
1458 if (result == 0)
1459 result = result2;
1460 }
1461 return result;
1462 }
1463
1464
1465 /* Close the device and release it. BKL is not needed: this is the only thread
1466 accessing this tape. */
st_release(struct inode * inode,struct file * filp)1467 static int st_release(struct inode *inode, struct file *filp)
1468 {
1469 struct scsi_tape *STp = filp->private_data;
1470
1471 if (STp->door_locked == ST_LOCKED_AUTO)
1472 do_door_lock(STp, 0);
1473
1474 normalize_buffer(STp->buffer);
1475 spin_lock(&st_use_lock);
1476 STp->in_use = 0;
1477 spin_unlock(&st_use_lock);
1478 scsi_autopm_put_device(STp->device);
1479 scsi_tape_put(STp);
1480
1481 return 0;
1482 }
1483
1484 /* The checks common to both reading and writing */
rw_checks(struct scsi_tape * STp,struct file * filp,size_t count)1485 static ssize_t rw_checks(struct scsi_tape *STp, struct file *filp, size_t count)
1486 {
1487 ssize_t retval = 0;
1488
1489 /*
1490 * If we are in the middle of error recovery, don't let anyone
1491 * else try and use this device. Also, if error recovery fails, it
1492 * may try and take the device offline, in which case all further
1493 * access to the device is prohibited.
1494 */
1495 if (!scsi_block_when_processing_errors(STp->device)) {
1496 retval = (-ENXIO);
1497 goto out;
1498 }
1499
1500 if (STp->ready != ST_READY) {
1501 if (STp->ready == ST_NO_TAPE)
1502 retval = (-ENOMEDIUM);
1503 else
1504 retval = (-EIO);
1505 goto out;
1506 }
1507
1508 if (! STp->modes[STp->current_mode].defined) {
1509 retval = (-ENXIO);
1510 goto out;
1511 }
1512
1513
1514 /*
1515 * If there was a bus reset, block further access
1516 * to this device.
1517 */
1518 if (STp->pos_unknown) {
1519 retval = (-EIO);
1520 goto out;
1521 }
1522
1523 if (count == 0)
1524 goto out;
1525
1526 DEB(
1527 if (!STp->in_use) {
1528 st_printk(ST_DEB_MSG, STp,
1529 "Incorrect device.\n");
1530 retval = (-EIO);
1531 goto out;
1532 } ) /* end DEB */
1533
1534 if (STp->can_partitions &&
1535 (retval = switch_partition(STp)) < 0)
1536 goto out;
1537
1538 if (STp->block_size == 0 && STp->max_block > 0 &&
1539 (count < STp->min_block || count > STp->max_block)) {
1540 retval = (-EINVAL);
1541 goto out;
1542 }
1543
1544 if (STp->do_auto_lock && STp->door_locked == ST_UNLOCKED &&
1545 !do_door_lock(STp, 1))
1546 STp->door_locked = ST_LOCKED_AUTO;
1547
1548 out:
1549 return retval;
1550 }
1551
1552
setup_buffering(struct scsi_tape * STp,const char __user * buf,size_t count,int is_read)1553 static int setup_buffering(struct scsi_tape *STp, const char __user *buf,
1554 size_t count, int is_read)
1555 {
1556 int i, bufsize, retval = 0;
1557 struct st_buffer *STbp = STp->buffer;
1558
1559 if (is_read)
1560 i = STp->try_dio_now && try_rdio;
1561 else
1562 i = STp->try_dio_now && try_wdio;
1563
1564 if (i && ((unsigned long)buf & queue_dma_alignment(
1565 STp->device->request_queue)) == 0) {
1566 i = sgl_map_user_pages(STbp, STbp->use_sg, (unsigned long)buf,
1567 count, (is_read ? READ : WRITE));
1568 if (i > 0) {
1569 STbp->do_dio = i;
1570 STbp->buffer_bytes = 0; /* can be used as transfer counter */
1571 }
1572 else
1573 STbp->do_dio = 0; /* fall back to buffering with any error */
1574 STbp->sg_segs = STbp->do_dio;
1575 DEB(
1576 if (STbp->do_dio) {
1577 STp->nbr_dio++;
1578 STp->nbr_pages += STbp->do_dio;
1579 }
1580 )
1581 } else
1582 STbp->do_dio = 0;
1583 DEB( STp->nbr_requests++; )
1584
1585 if (!STbp->do_dio) {
1586 if (STp->block_size)
1587 bufsize = STp->block_size > st_fixed_buffer_size ?
1588 STp->block_size : st_fixed_buffer_size;
1589 else {
1590 bufsize = count;
1591 /* Make sure that data from previous user is not leaked even if
1592 HBA does not return correct residual */
1593 if (is_read && STp->sili && !STbp->cleared)
1594 clear_buffer(STbp);
1595 }
1596
1597 if (bufsize > STbp->buffer_size &&
1598 !enlarge_buffer(STbp, bufsize)) {
1599 st_printk(KERN_WARNING, STp,
1600 "Can't allocate %d byte tape buffer.\n",
1601 bufsize);
1602 retval = (-EOVERFLOW);
1603 goto out;
1604 }
1605 if (STp->block_size)
1606 STbp->buffer_blocks = bufsize / STp->block_size;
1607 }
1608
1609 out:
1610 return retval;
1611 }
1612
1613
1614 /* Can be called more than once after each setup_buffer() */
release_buffering(struct scsi_tape * STp,int is_read)1615 static void release_buffering(struct scsi_tape *STp, int is_read)
1616 {
1617 struct st_buffer *STbp;
1618
1619 STbp = STp->buffer;
1620 if (STbp->do_dio) {
1621 sgl_unmap_user_pages(STbp, STbp->do_dio, is_read);
1622 STbp->do_dio = 0;
1623 STbp->sg_segs = 0;
1624 }
1625 }
1626
1627
1628 /* Write command */
1629 static ssize_t
st_write(struct file * filp,const char __user * buf,size_t count,loff_t * ppos)1630 st_write(struct file *filp, const char __user *buf, size_t count, loff_t * ppos)
1631 {
1632 ssize_t total;
1633 ssize_t i, do_count, blks, transfer;
1634 ssize_t retval;
1635 int undone, retry_eot = 0, scode;
1636 int async_write;
1637 unsigned char cmd[MAX_COMMAND_SIZE];
1638 const char __user *b_point;
1639 struct st_request *SRpnt = NULL;
1640 struct scsi_tape *STp = filp->private_data;
1641 struct st_modedef *STm;
1642 struct st_partstat *STps;
1643 struct st_buffer *STbp;
1644
1645 if (mutex_lock_interruptible(&STp->lock))
1646 return -ERESTARTSYS;
1647
1648 retval = rw_checks(STp, filp, count);
1649 if (retval || count == 0)
1650 goto out;
1651
1652 /* Write must be integral number of blocks */
1653 if (STp->block_size != 0 && (count % STp->block_size) != 0) {
1654 st_printk(KERN_WARNING, STp,
1655 "Write not multiple of tape block size.\n");
1656 retval = (-EINVAL);
1657 goto out;
1658 }
1659
1660 STm = &(STp->modes[STp->current_mode]);
1661 STps = &(STp->ps[STp->partition]);
1662
1663 if (STp->write_prot) {
1664 retval = (-EACCES);
1665 goto out;
1666 }
1667
1668
1669 if (STps->rw == ST_READING) {
1670 retval = flush_buffer(STp, 0);
1671 if (retval)
1672 goto out;
1673 STps->rw = ST_WRITING;
1674 } else if (STps->rw != ST_WRITING &&
1675 STps->drv_file == 0 && STps->drv_block == 0) {
1676 if ((retval = set_mode_densblk(STp, STm)) < 0)
1677 goto out;
1678 if (STm->default_compression != ST_DONT_TOUCH &&
1679 !(STp->compression_changed)) {
1680 if (st_compression(STp, (STm->default_compression == ST_YES))) {
1681 st_printk(KERN_WARNING, STp,
1682 "Can't set default compression.\n");
1683 if (modes_defined) {
1684 retval = (-EINVAL);
1685 goto out;
1686 }
1687 }
1688 }
1689 }
1690
1691 STbp = STp->buffer;
1692 i = write_behind_check(STp);
1693 if (i) {
1694 if (i == -ENOSPC)
1695 STps->eof = ST_EOM_OK;
1696 else
1697 STps->eof = ST_EOM_ERROR;
1698 }
1699
1700 if (STps->eof == ST_EOM_OK) {
1701 STps->eof = ST_EOD_1; /* allow next write */
1702 retval = (-ENOSPC);
1703 goto out;
1704 }
1705 else if (STps->eof == ST_EOM_ERROR) {
1706 retval = (-EIO);
1707 goto out;
1708 }
1709
1710 /* Check the buffer readability in cases where copy_user might catch
1711 the problems after some tape movement. */
1712 if (STp->block_size != 0 &&
1713 !STbp->do_dio &&
1714 (copy_from_user(&i, buf, 1) != 0 ||
1715 copy_from_user(&i, buf + count - 1, 1) != 0)) {
1716 retval = (-EFAULT);
1717 goto out;
1718 }
1719
1720 retval = setup_buffering(STp, buf, count, 0);
1721 if (retval)
1722 goto out;
1723
1724 total = count;
1725
1726 memset(cmd, 0, MAX_COMMAND_SIZE);
1727 cmd[0] = WRITE_6;
1728 cmd[1] = (STp->block_size != 0);
1729
1730 STps->rw = ST_WRITING;
1731
1732 b_point = buf;
1733 while (count > 0 && !retry_eot) {
1734
1735 if (STbp->do_dio) {
1736 do_count = count;
1737 }
1738 else {
1739 if (STp->block_size == 0)
1740 do_count = count;
1741 else {
1742 do_count = STbp->buffer_blocks * STp->block_size -
1743 STbp->buffer_bytes;
1744 if (do_count > count)
1745 do_count = count;
1746 }
1747
1748 i = append_to_buffer(b_point, STbp, do_count);
1749 if (i) {
1750 retval = i;
1751 goto out;
1752 }
1753 }
1754 count -= do_count;
1755 b_point += do_count;
1756
1757 async_write = STp->block_size == 0 && !STbp->do_dio &&
1758 STm->do_async_writes && STps->eof < ST_EOM_OK;
1759
1760 if (STp->block_size != 0 && STm->do_buffer_writes &&
1761 !(STp->try_dio_now && try_wdio) && STps->eof < ST_EOM_OK &&
1762 STbp->buffer_bytes < STbp->buffer_size) {
1763 STp->dirty = 1;
1764 /* Don't write a buffer that is not full enough. */
1765 if (!async_write && count == 0)
1766 break;
1767 }
1768
1769 retry_write:
1770 if (STp->block_size == 0)
1771 blks = transfer = do_count;
1772 else {
1773 if (!STbp->do_dio)
1774 blks = STbp->buffer_bytes;
1775 else
1776 blks = do_count;
1777 blks /= STp->block_size;
1778 transfer = blks * STp->block_size;
1779 }
1780 cmd[2] = blks >> 16;
1781 cmd[3] = blks >> 8;
1782 cmd[4] = blks;
1783
1784 SRpnt = st_do_scsi(SRpnt, STp, cmd, transfer, DMA_TO_DEVICE,
1785 STp->device->request_queue->rq_timeout,
1786 MAX_WRITE_RETRIES, !async_write);
1787 if (!SRpnt) {
1788 retval = STbp->syscall_result;
1789 goto out;
1790 }
1791 if (async_write && !STbp->syscall_result) {
1792 STbp->writing = transfer;
1793 STp->dirty = !(STbp->writing ==
1794 STbp->buffer_bytes);
1795 SRpnt = NULL; /* Prevent releasing this request! */
1796 DEB( STp->write_pending = 1; )
1797 break;
1798 }
1799
1800 if (STbp->syscall_result != 0) {
1801 struct st_cmdstatus *cmdstatp = &STp->buffer->cmdstat;
1802
1803 DEBC_printk(STp, "Error on write:\n");
1804 if (cmdstatp->have_sense && (cmdstatp->flags & SENSE_EOM)) {
1805 scode = cmdstatp->sense_hdr.sense_key;
1806 if (cmdstatp->remainder_valid)
1807 undone = (int)cmdstatp->uremainder64;
1808 else if (STp->block_size == 0 &&
1809 scode == VOLUME_OVERFLOW)
1810 undone = transfer;
1811 else
1812 undone = 0;
1813 if (STp->block_size != 0)
1814 undone *= STp->block_size;
1815 if (undone <= do_count) {
1816 /* Only data from this write is not written */
1817 count += undone;
1818 b_point -= undone;
1819 do_count -= undone;
1820 if (STp->block_size)
1821 blks = (transfer - undone) / STp->block_size;
1822 STps->eof = ST_EOM_OK;
1823 /* Continue in fixed block mode if all written
1824 in this request but still something left to write
1825 (retval left to zero)
1826 */
1827 if (STp->block_size == 0 ||
1828 undone > 0 || count == 0)
1829 retval = (-ENOSPC); /* EOM within current request */
1830 DEBC_printk(STp, "EOM with %d "
1831 "bytes unwritten.\n",
1832 (int)count);
1833 } else {
1834 /* EOT within data buffered earlier (possible only
1835 in fixed block mode without direct i/o) */
1836 if (!retry_eot && !cmdstatp->deferred &&
1837 (scode == NO_SENSE || scode == RECOVERED_ERROR)) {
1838 move_buffer_data(STp->buffer, transfer - undone);
1839 retry_eot = 1;
1840 if (STps->drv_block >= 0) {
1841 STps->drv_block += (transfer - undone) /
1842 STp->block_size;
1843 }
1844 STps->eof = ST_EOM_OK;
1845 DEBC_printk(STp, "Retry "
1846 "write of %d "
1847 "bytes at EOM.\n",
1848 STp->buffer->buffer_bytes);
1849 goto retry_write;
1850 }
1851 else {
1852 /* Either error within data buffered by driver or
1853 failed retry */
1854 count -= do_count;
1855 blks = do_count = 0;
1856 STps->eof = ST_EOM_ERROR;
1857 STps->drv_block = (-1); /* Too cautious? */
1858 retval = (-EIO); /* EOM for old data */
1859 DEBC_printk(STp, "EOM with "
1860 "lost data.\n");
1861 }
1862 }
1863 } else {
1864 count += do_count;
1865 STps->drv_block = (-1); /* Too cautious? */
1866 retval = STbp->syscall_result;
1867 }
1868
1869 }
1870
1871 if (STps->drv_block >= 0) {
1872 if (STp->block_size == 0)
1873 STps->drv_block += (do_count > 0);
1874 else
1875 STps->drv_block += blks;
1876 }
1877
1878 STbp->buffer_bytes = 0;
1879 STp->dirty = 0;
1880
1881 if (retval || retry_eot) {
1882 if (count < total)
1883 retval = total - count;
1884 goto out;
1885 }
1886 }
1887
1888 if (STps->eof == ST_EOD_1)
1889 STps->eof = ST_EOM_OK;
1890 else if (STps->eof != ST_EOM_OK)
1891 STps->eof = ST_NOEOF;
1892 retval = total - count;
1893
1894 out:
1895 if (SRpnt != NULL)
1896 st_release_request(SRpnt);
1897 release_buffering(STp, 0);
1898 mutex_unlock(&STp->lock);
1899
1900 return retval;
1901 }
1902
1903 /* Read data from the tape. Returns zero in the normal case, one if the
1904 eof status has changed, and the negative error code in case of a
1905 fatal error. Otherwise updates the buffer and the eof state.
1906
1907 Does release user buffer mapping if it is set.
1908 */
read_tape(struct scsi_tape * STp,long count,struct st_request ** aSRpnt)1909 static long read_tape(struct scsi_tape *STp, long count,
1910 struct st_request ** aSRpnt)
1911 {
1912 int transfer, blks, bytes;
1913 unsigned char cmd[MAX_COMMAND_SIZE];
1914 struct st_request *SRpnt;
1915 struct st_modedef *STm;
1916 struct st_partstat *STps;
1917 struct st_buffer *STbp;
1918 int retval = 0;
1919
1920 if (count == 0)
1921 return 0;
1922
1923 STm = &(STp->modes[STp->current_mode]);
1924 STps = &(STp->ps[STp->partition]);
1925 if (STps->eof == ST_FM_HIT)
1926 return 1;
1927 STbp = STp->buffer;
1928
1929 if (STp->block_size == 0)
1930 blks = bytes = count;
1931 else {
1932 if (!(STp->try_dio_now && try_rdio) && STm->do_read_ahead) {
1933 blks = (STp->buffer)->buffer_blocks;
1934 bytes = blks * STp->block_size;
1935 } else {
1936 bytes = count;
1937 if (!STbp->do_dio && bytes > (STp->buffer)->buffer_size)
1938 bytes = (STp->buffer)->buffer_size;
1939 blks = bytes / STp->block_size;
1940 bytes = blks * STp->block_size;
1941 }
1942 }
1943
1944 memset(cmd, 0, MAX_COMMAND_SIZE);
1945 cmd[0] = READ_6;
1946 cmd[1] = (STp->block_size != 0);
1947 if (!cmd[1] && STp->sili)
1948 cmd[1] |= 2;
1949 cmd[2] = blks >> 16;
1950 cmd[3] = blks >> 8;
1951 cmd[4] = blks;
1952
1953 SRpnt = *aSRpnt;
1954 SRpnt = st_do_scsi(SRpnt, STp, cmd, bytes, DMA_FROM_DEVICE,
1955 STp->device->request_queue->rq_timeout,
1956 MAX_RETRIES, 1);
1957 release_buffering(STp, 1);
1958 *aSRpnt = SRpnt;
1959 if (!SRpnt)
1960 return STbp->syscall_result;
1961
1962 STbp->read_pointer = 0;
1963 STps->at_sm = 0;
1964
1965 /* Something to check */
1966 if (STbp->syscall_result) {
1967 struct st_cmdstatus *cmdstatp = &STp->buffer->cmdstat;
1968
1969 retval = 1;
1970 DEBC_printk(STp,
1971 "Sense: %2x %2x %2x %2x %2x %2x %2x %2x\n",
1972 SRpnt->sense[0], SRpnt->sense[1],
1973 SRpnt->sense[2], SRpnt->sense[3],
1974 SRpnt->sense[4], SRpnt->sense[5],
1975 SRpnt->sense[6], SRpnt->sense[7]);
1976 if (cmdstatp->have_sense) {
1977
1978 if (cmdstatp->sense_hdr.sense_key == BLANK_CHECK)
1979 cmdstatp->flags &= 0xcf; /* No need for EOM in this case */
1980
1981 if (cmdstatp->flags != 0) { /* EOF, EOM, or ILI */
1982 /* Compute the residual count */
1983 if (cmdstatp->remainder_valid)
1984 transfer = (int)cmdstatp->uremainder64;
1985 else
1986 transfer = 0;
1987 if (cmdstatp->sense_hdr.sense_key == MEDIUM_ERROR) {
1988 if (STp->block_size == 0)
1989 transfer = bytes;
1990 /* Some drives set ILI with MEDIUM ERROR */
1991 cmdstatp->flags &= ~SENSE_ILI;
1992 }
1993
1994 if (cmdstatp->flags & SENSE_ILI) { /* ILI */
1995 if (STp->block_size == 0 &&
1996 transfer < 0) {
1997 st_printk(KERN_NOTICE, STp,
1998 "Failed to read %d "
1999 "byte block with %d "
2000 "byte transfer.\n",
2001 bytes - transfer,
2002 bytes);
2003 if (STps->drv_block >= 0)
2004 STps->drv_block += 1;
2005 STbp->buffer_bytes = 0;
2006 return (-ENOMEM);
2007 } else if (STp->block_size == 0) {
2008 STbp->buffer_bytes = bytes - transfer;
2009 } else {
2010 st_release_request(SRpnt);
2011 SRpnt = *aSRpnt = NULL;
2012 if (transfer == blks) { /* We did not get anything, error */
2013 st_printk(KERN_NOTICE, STp,
2014 "Incorrect "
2015 "block size.\n");
2016 if (STps->drv_block >= 0)
2017 STps->drv_block += blks - transfer + 1;
2018 st_int_ioctl(STp, MTBSR, 1);
2019 return (-EIO);
2020 }
2021 /* We have some data, deliver it */
2022 STbp->buffer_bytes = (blks - transfer) *
2023 STp->block_size;
2024 DEBC_printk(STp, "ILI but "
2025 "enough data "
2026 "received %ld "
2027 "%d.\n", count,
2028 STbp->buffer_bytes);
2029 if (STps->drv_block >= 0)
2030 STps->drv_block += 1;
2031 if (st_int_ioctl(STp, MTBSR, 1))
2032 return (-EIO);
2033 }
2034 } else if (cmdstatp->flags & SENSE_FMK) { /* FM overrides EOM */
2035 if (STps->eof != ST_FM_HIT)
2036 STps->eof = ST_FM_HIT;
2037 else
2038 STps->eof = ST_EOD_2;
2039 if (STp->block_size == 0)
2040 STbp->buffer_bytes = 0;
2041 else
2042 STbp->buffer_bytes =
2043 bytes - transfer * STp->block_size;
2044 DEBC_printk(STp, "EOF detected (%d "
2045 "bytes read).\n",
2046 STbp->buffer_bytes);
2047 } else if (cmdstatp->flags & SENSE_EOM) {
2048 if (STps->eof == ST_FM)
2049 STps->eof = ST_EOD_1;
2050 else
2051 STps->eof = ST_EOM_OK;
2052 if (STp->block_size == 0)
2053 STbp->buffer_bytes = bytes - transfer;
2054 else
2055 STbp->buffer_bytes =
2056 bytes - transfer * STp->block_size;
2057
2058 DEBC_printk(STp, "EOM detected (%d "
2059 "bytes read).\n",
2060 STbp->buffer_bytes);
2061 }
2062 }
2063 /* end of EOF, EOM, ILI test */
2064 else { /* nonzero sense key */
2065 DEBC_printk(STp, "Tape error while reading.\n");
2066 STps->drv_block = (-1);
2067 if (STps->eof == ST_FM &&
2068 cmdstatp->sense_hdr.sense_key == BLANK_CHECK) {
2069 DEBC_printk(STp, "Zero returned for "
2070 "first BLANK CHECK "
2071 "after EOF.\n");
2072 STps->eof = ST_EOD_2; /* First BLANK_CHECK after FM */
2073 } else /* Some other extended sense code */
2074 retval = (-EIO);
2075 }
2076
2077 if (STbp->buffer_bytes < 0) /* Caused by bogus sense data */
2078 STbp->buffer_bytes = 0;
2079 }
2080 /* End of extended sense test */
2081 else { /* Non-extended sense */
2082 retval = STbp->syscall_result;
2083 }
2084
2085 }
2086 /* End of error handling */
2087 else { /* Read successful */
2088 STbp->buffer_bytes = bytes;
2089 if (STp->sili) /* In fixed block mode residual is always zero here */
2090 STbp->buffer_bytes -= STp->buffer->cmdstat.residual;
2091 }
2092
2093 if (STps->drv_block >= 0) {
2094 if (STp->block_size == 0)
2095 STps->drv_block++;
2096 else
2097 STps->drv_block += STbp->buffer_bytes / STp->block_size;
2098 }
2099 return retval;
2100 }
2101
2102
2103 /* Read command */
2104 static ssize_t
st_read(struct file * filp,char __user * buf,size_t count,loff_t * ppos)2105 st_read(struct file *filp, char __user *buf, size_t count, loff_t * ppos)
2106 {
2107 ssize_t total;
2108 ssize_t retval = 0;
2109 ssize_t i, transfer;
2110 int special, do_dio = 0;
2111 struct st_request *SRpnt = NULL;
2112 struct scsi_tape *STp = filp->private_data;
2113 struct st_modedef *STm;
2114 struct st_partstat *STps;
2115 struct st_buffer *STbp = STp->buffer;
2116
2117 if (mutex_lock_interruptible(&STp->lock))
2118 return -ERESTARTSYS;
2119
2120 retval = rw_checks(STp, filp, count);
2121 if (retval || count == 0)
2122 goto out;
2123
2124 STm = &(STp->modes[STp->current_mode]);
2125 if (STp->block_size != 0 && (count % STp->block_size) != 0) {
2126 if (!STm->do_read_ahead) {
2127 retval = (-EINVAL); /* Read must be integral number of blocks */
2128 goto out;
2129 }
2130 STp->try_dio_now = 0; /* Direct i/o can't handle split blocks */
2131 }
2132
2133 STps = &(STp->ps[STp->partition]);
2134 if (STps->rw == ST_WRITING) {
2135 retval = flush_buffer(STp, 0);
2136 if (retval)
2137 goto out;
2138 STps->rw = ST_READING;
2139 }
2140 DEB(
2141 if (debugging && STps->eof != ST_NOEOF)
2142 st_printk(ST_DEB_MSG, STp,
2143 "EOF/EOM flag up (%d). Bytes %d\n",
2144 STps->eof, STbp->buffer_bytes);
2145 ) /* end DEB */
2146
2147 retval = setup_buffering(STp, buf, count, 1);
2148 if (retval)
2149 goto out;
2150 do_dio = STbp->do_dio;
2151
2152 if (STbp->buffer_bytes == 0 &&
2153 STps->eof >= ST_EOD_1) {
2154 if (STps->eof < ST_EOD) {
2155 STps->eof += 1;
2156 retval = 0;
2157 goto out;
2158 }
2159 retval = (-EIO); /* EOM or Blank Check */
2160 goto out;
2161 }
2162
2163 if (do_dio) {
2164 /* Check the buffer writability before any tape movement. Don't alter
2165 buffer data. */
2166 if (copy_from_user(&i, buf, 1) != 0 ||
2167 copy_to_user(buf, &i, 1) != 0 ||
2168 copy_from_user(&i, buf + count - 1, 1) != 0 ||
2169 copy_to_user(buf + count - 1, &i, 1) != 0) {
2170 retval = (-EFAULT);
2171 goto out;
2172 }
2173 }
2174
2175 STps->rw = ST_READING;
2176
2177
2178 /* Loop until enough data in buffer or a special condition found */
2179 for (total = 0, special = 0; total < count && !special;) {
2180
2181 /* Get new data if the buffer is empty */
2182 if (STbp->buffer_bytes == 0) {
2183 special = read_tape(STp, count - total, &SRpnt);
2184 if (special < 0) { /* No need to continue read */
2185 retval = special;
2186 goto out;
2187 }
2188 }
2189
2190 /* Move the data from driver buffer to user buffer */
2191 if (STbp->buffer_bytes > 0) {
2192 DEB(
2193 if (debugging && STps->eof != ST_NOEOF)
2194 st_printk(ST_DEB_MSG, STp,
2195 "EOF up (%d). Left %d, needed %d.\n",
2196 STps->eof, STbp->buffer_bytes,
2197 (int)(count - total));
2198 ) /* end DEB */
2199 transfer = STbp->buffer_bytes < count - total ?
2200 STbp->buffer_bytes : count - total;
2201 if (!do_dio) {
2202 i = from_buffer(STbp, buf, transfer);
2203 if (i) {
2204 retval = i;
2205 goto out;
2206 }
2207 }
2208 buf += transfer;
2209 total += transfer;
2210 }
2211
2212 if (STp->block_size == 0)
2213 break; /* Read only one variable length block */
2214
2215 } /* for (total = 0, special = 0;
2216 total < count && !special; ) */
2217
2218 /* Change the eof state if no data from tape or buffer */
2219 if (total == 0) {
2220 if (STps->eof == ST_FM_HIT) {
2221 STps->eof = ST_FM;
2222 STps->drv_block = 0;
2223 if (STps->drv_file >= 0)
2224 STps->drv_file++;
2225 } else if (STps->eof == ST_EOD_1) {
2226 STps->eof = ST_EOD_2;
2227 STps->drv_block = 0;
2228 if (STps->drv_file >= 0)
2229 STps->drv_file++;
2230 } else if (STps->eof == ST_EOD_2)
2231 STps->eof = ST_EOD;
2232 } else if (STps->eof == ST_FM)
2233 STps->eof = ST_NOEOF;
2234 retval = total;
2235
2236 out:
2237 if (SRpnt != NULL) {
2238 st_release_request(SRpnt);
2239 SRpnt = NULL;
2240 }
2241 if (do_dio) {
2242 release_buffering(STp, 1);
2243 STbp->buffer_bytes = 0;
2244 }
2245 mutex_unlock(&STp->lock);
2246
2247 return retval;
2248 }
2249
2250
2251
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); } } )2252 DEB(
2253 /* Set the driver options */
2254 static void st_log_options(struct scsi_tape * STp, struct st_modedef * STm)
2255 {
2256 if (debugging) {
2257 st_printk(KERN_INFO, STp,
2258 "Mode %d options: buffer writes: %d, "
2259 "async writes: %d, read ahead: %d\n",
2260 STp->current_mode, STm->do_buffer_writes,
2261 STm->do_async_writes, STm->do_read_ahead);
2262 st_printk(KERN_INFO, STp,
2263 " can bsr: %d, two FMs: %d, "
2264 "fast mteom: %d, auto lock: %d,\n",
2265 STp->can_bsr, STp->two_fm, STp->fast_mteom,
2266 STp->do_auto_lock);
2267 st_printk(KERN_INFO, STp,
2268 " defs for wr: %d, no block limits: %d, "
2269 "partitions: %d, s2 log: %d\n",
2270 STm->defaults_for_writes, STp->omit_blklims,
2271 STp->can_partitions, STp->scsi2_logical);
2272 st_printk(KERN_INFO, STp,
2273 " sysv: %d nowait: %d sili: %d "
2274 "nowait_filemark: %d\n",
2275 STm->sysv, STp->immediate, STp->sili,
2276 STp->immediate_filemark);
2277 st_printk(KERN_INFO, STp, " debugging: %d\n", debugging);
2278 }
2279 }
2280 )
2281
2282
2283 static int st_set_options(struct scsi_tape *STp, long options)
2284 {
2285 int value;
2286 long code;
2287 struct st_modedef *STm;
2288 struct cdev *cd0, *cd1;
2289 struct device *d0, *d1;
2290
2291 STm = &(STp->modes[STp->current_mode]);
2292 if (!STm->defined) {
2293 cd0 = STm->cdevs[0];
2294 cd1 = STm->cdevs[1];
2295 d0 = STm->devs[0];
2296 d1 = STm->devs[1];
2297 memcpy(STm, &(STp->modes[0]), sizeof(struct st_modedef));
2298 STm->cdevs[0] = cd0;
2299 STm->cdevs[1] = cd1;
2300 STm->devs[0] = d0;
2301 STm->devs[1] = d1;
2302 modes_defined = 1;
2303 DEBC_printk(STp, "Initialized mode %d definition from mode 0\n",
2304 STp->current_mode);
2305 }
2306
2307 code = options & MT_ST_OPTIONS;
2308 if (code == MT_ST_BOOLEANS) {
2309 STm->do_buffer_writes = (options & MT_ST_BUFFER_WRITES) != 0;
2310 STm->do_async_writes = (options & MT_ST_ASYNC_WRITES) != 0;
2311 STm->defaults_for_writes = (options & MT_ST_DEF_WRITES) != 0;
2312 STm->do_read_ahead = (options & MT_ST_READ_AHEAD) != 0;
2313 STp->two_fm = (options & MT_ST_TWO_FM) != 0;
2314 STp->fast_mteom = (options & MT_ST_FAST_MTEOM) != 0;
2315 STp->do_auto_lock = (options & MT_ST_AUTO_LOCK) != 0;
2316 STp->can_bsr = (options & MT_ST_CAN_BSR) != 0;
2317 STp->omit_blklims = (options & MT_ST_NO_BLKLIMS) != 0;
2318 if ((STp->device)->scsi_level >= SCSI_2)
2319 STp->can_partitions = (options & MT_ST_CAN_PARTITIONS) != 0;
2320 STp->scsi2_logical = (options & MT_ST_SCSI2LOGICAL) != 0;
2321 STp->immediate = (options & MT_ST_NOWAIT) != 0;
2322 STp->immediate_filemark = (options & MT_ST_NOWAIT_EOF) != 0;
2323 STm->sysv = (options & MT_ST_SYSV) != 0;
2324 STp->sili = (options & MT_ST_SILI) != 0;
2325 DEB( debugging = (options & MT_ST_DEBUGGING) != 0;
2326 st_log_options(STp, STm); )
2327 } else if (code == MT_ST_SETBOOLEANS || code == MT_ST_CLEARBOOLEANS) {
2328 value = (code == MT_ST_SETBOOLEANS);
2329 if ((options & MT_ST_BUFFER_WRITES) != 0)
2330 STm->do_buffer_writes = value;
2331 if ((options & MT_ST_ASYNC_WRITES) != 0)
2332 STm->do_async_writes = value;
2333 if ((options & MT_ST_DEF_WRITES) != 0)
2334 STm->defaults_for_writes = value;
2335 if ((options & MT_ST_READ_AHEAD) != 0)
2336 STm->do_read_ahead = value;
2337 if ((options & MT_ST_TWO_FM) != 0)
2338 STp->two_fm = value;
2339 if ((options & MT_ST_FAST_MTEOM) != 0)
2340 STp->fast_mteom = value;
2341 if ((options & MT_ST_AUTO_LOCK) != 0)
2342 STp->do_auto_lock = value;
2343 if ((options & MT_ST_CAN_BSR) != 0)
2344 STp->can_bsr = value;
2345 if ((options & MT_ST_NO_BLKLIMS) != 0)
2346 STp->omit_blklims = value;
2347 if ((STp->device)->scsi_level >= SCSI_2 &&
2348 (options & MT_ST_CAN_PARTITIONS) != 0)
2349 STp->can_partitions = value;
2350 if ((options & MT_ST_SCSI2LOGICAL) != 0)
2351 STp->scsi2_logical = value;
2352 if ((options & MT_ST_NOWAIT) != 0)
2353 STp->immediate = value;
2354 if ((options & MT_ST_NOWAIT_EOF) != 0)
2355 STp->immediate_filemark = value;
2356 if ((options & MT_ST_SYSV) != 0)
2357 STm->sysv = value;
2358 if ((options & MT_ST_SILI) != 0)
2359 STp->sili = value;
2360 DEB(
2361 if ((options & MT_ST_DEBUGGING) != 0)
2362 debugging = value;
2363 st_log_options(STp, STm); )
2364 } else if (code == MT_ST_WRITE_THRESHOLD) {
2365 /* Retained for compatibility */
2366 } else if (code == MT_ST_DEF_BLKSIZE) {
2367 value = (options & ~MT_ST_OPTIONS);
2368 if (value == ~MT_ST_OPTIONS) {
2369 STm->default_blksize = (-1);
2370 DEBC_printk(STp, "Default block size disabled.\n");
2371 } else {
2372 STm->default_blksize = value;
2373 DEBC_printk(STp,"Default block size set to "
2374 "%d bytes.\n", STm->default_blksize);
2375 if (STp->ready == ST_READY) {
2376 STp->blksize_changed = 0;
2377 set_mode_densblk(STp, STm);
2378 }
2379 }
2380 } else if (code == MT_ST_TIMEOUTS) {
2381 value = (options & ~MT_ST_OPTIONS);
2382 if ((value & MT_ST_SET_LONG_TIMEOUT) != 0) {
2383 STp->long_timeout = (value & ~MT_ST_SET_LONG_TIMEOUT) * HZ;
2384 DEBC_printk(STp, "Long timeout set to %d seconds.\n",
2385 (value & ~MT_ST_SET_LONG_TIMEOUT));
2386 } else {
2387 blk_queue_rq_timeout(STp->device->request_queue,
2388 value * HZ);
2389 DEBC_printk(STp, "Normal timeout set to %d seconds.\n",
2390 value);
2391 }
2392 } else if (code == MT_ST_SET_CLN) {
2393 value = (options & ~MT_ST_OPTIONS) & 0xff;
2394 if (value != 0 &&
2395 (value < EXTENDED_SENSE_START ||
2396 value >= SCSI_SENSE_BUFFERSIZE))
2397 return (-EINVAL);
2398 STp->cln_mode = value;
2399 STp->cln_sense_mask = (options >> 8) & 0xff;
2400 STp->cln_sense_value = (options >> 16) & 0xff;
2401 st_printk(KERN_INFO, STp,
2402 "Cleaning request mode %d, mask %02x, value %02x\n",
2403 value, STp->cln_sense_mask, STp->cln_sense_value);
2404 } else if (code == MT_ST_DEF_OPTIONS) {
2405 code = (options & ~MT_ST_CLEAR_DEFAULT);
2406 value = (options & MT_ST_CLEAR_DEFAULT);
2407 if (code == MT_ST_DEF_DENSITY) {
2408 if (value == MT_ST_CLEAR_DEFAULT) {
2409 STm->default_density = (-1);
2410 DEBC_printk(STp,
2411 "Density default disabled.\n");
2412 } else {
2413 STm->default_density = value & 0xff;
2414 DEBC_printk(STp, "Density default set to %x\n",
2415 STm->default_density);
2416 if (STp->ready == ST_READY) {
2417 STp->density_changed = 0;
2418 set_mode_densblk(STp, STm);
2419 }
2420 }
2421 } else if (code == MT_ST_DEF_DRVBUFFER) {
2422 if (value == MT_ST_CLEAR_DEFAULT) {
2423 STp->default_drvbuffer = 0xff;
2424 DEBC_printk(STp,
2425 "Drive buffer default disabled.\n");
2426 } else {
2427 STp->default_drvbuffer = value & 7;
2428 DEBC_printk(STp,
2429 "Drive buffer default set to %x\n",
2430 STp->default_drvbuffer);
2431 if (STp->ready == ST_READY)
2432 st_int_ioctl(STp, MTSETDRVBUFFER, STp->default_drvbuffer);
2433 }
2434 } else if (code == MT_ST_DEF_COMPRESSION) {
2435 if (value == MT_ST_CLEAR_DEFAULT) {
2436 STm->default_compression = ST_DONT_TOUCH;
2437 DEBC_printk(STp,
2438 "Compression default disabled.\n");
2439 } else {
2440 if ((value & 0xff00) != 0) {
2441 STp->c_algo = (value & 0xff00) >> 8;
2442 DEBC_printk(STp, "Compression "
2443 "algorithm set to 0x%x.\n",
2444 STp->c_algo);
2445 }
2446 if ((value & 0xff) != 0xff) {
2447 STm->default_compression = (value & 1 ? ST_YES : ST_NO);
2448 DEBC_printk(STp, "Compression default "
2449 "set to %x\n",
2450 (value & 1));
2451 if (STp->ready == ST_READY) {
2452 STp->compression_changed = 0;
2453 st_compression(STp, (STm->default_compression == ST_YES));
2454 }
2455 }
2456 }
2457 }
2458 } else
2459 return (-EIO);
2460
2461 return 0;
2462 }
2463
2464 #define MODE_HEADER_LENGTH 4
2465
2466 /* Mode header and page byte offsets */
2467 #define MH_OFF_DATA_LENGTH 0
2468 #define MH_OFF_MEDIUM_TYPE 1
2469 #define MH_OFF_DEV_SPECIFIC 2
2470 #define MH_OFF_BDESCS_LENGTH 3
2471 #define MP_OFF_PAGE_NBR 0
2472 #define MP_OFF_PAGE_LENGTH 1
2473
2474 /* Mode header and page bit masks */
2475 #define MH_BIT_WP 0x80
2476 #define MP_MSK_PAGE_NBR 0x3f
2477
2478 /* Don't return block descriptors */
2479 #define MODE_SENSE_OMIT_BDESCS 0x08
2480
2481 #define MODE_SELECT_PAGE_FORMAT 0x10
2482
2483 /* Read a mode page into the tape buffer. The block descriptors are included
2484 if incl_block_descs is true. The page control is ored to the page number
2485 parameter, if necessary. */
read_mode_page(struct scsi_tape * STp,int page,int omit_block_descs)2486 static int read_mode_page(struct scsi_tape *STp, int page, int omit_block_descs)
2487 {
2488 unsigned char cmd[MAX_COMMAND_SIZE];
2489 struct st_request *SRpnt;
2490
2491 memset(cmd, 0, MAX_COMMAND_SIZE);
2492 cmd[0] = MODE_SENSE;
2493 if (omit_block_descs)
2494 cmd[1] = MODE_SENSE_OMIT_BDESCS;
2495 cmd[2] = page;
2496 cmd[4] = 255;
2497
2498 SRpnt = st_do_scsi(NULL, STp, cmd, cmd[4], DMA_FROM_DEVICE,
2499 STp->device->request_queue->rq_timeout, 0, 1);
2500 if (SRpnt == NULL)
2501 return (STp->buffer)->syscall_result;
2502
2503 st_release_request(SRpnt);
2504
2505 return STp->buffer->syscall_result;
2506 }
2507
2508
2509 /* Send the mode page in the tape buffer to the drive. Assumes that the mode data
2510 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)2511 static int write_mode_page(struct scsi_tape *STp, int page, int slow)
2512 {
2513 int pgo;
2514 unsigned char cmd[MAX_COMMAND_SIZE];
2515 struct st_request *SRpnt;
2516 int timeout;
2517
2518 memset(cmd, 0, MAX_COMMAND_SIZE);
2519 cmd[0] = MODE_SELECT;
2520 cmd[1] = MODE_SELECT_PAGE_FORMAT;
2521 pgo = MODE_HEADER_LENGTH + (STp->buffer)->b_data[MH_OFF_BDESCS_LENGTH];
2522 cmd[4] = pgo + (STp->buffer)->b_data[pgo + MP_OFF_PAGE_LENGTH] + 2;
2523
2524 /* Clear reserved fields */
2525 (STp->buffer)->b_data[MH_OFF_DATA_LENGTH] = 0;
2526 (STp->buffer)->b_data[MH_OFF_MEDIUM_TYPE] = 0;
2527 (STp->buffer)->b_data[MH_OFF_DEV_SPECIFIC] &= ~MH_BIT_WP;
2528 (STp->buffer)->b_data[pgo + MP_OFF_PAGE_NBR] &= MP_MSK_PAGE_NBR;
2529
2530 timeout = slow ?
2531 STp->long_timeout : STp->device->request_queue->rq_timeout;
2532 SRpnt = st_do_scsi(NULL, STp, cmd, cmd[4], DMA_TO_DEVICE,
2533 timeout, 0, 1);
2534 if (SRpnt == NULL)
2535 return (STp->buffer)->syscall_result;
2536
2537 st_release_request(SRpnt);
2538
2539 return STp->buffer->syscall_result;
2540 }
2541
2542
2543 #define COMPRESSION_PAGE 0x0f
2544 #define COMPRESSION_PAGE_LENGTH 16
2545
2546 #define CP_OFF_DCE_DCC 2
2547 #define CP_OFF_C_ALGO 7
2548
2549 #define DCE_MASK 0x80
2550 #define DCC_MASK 0x40
2551 #define RED_MASK 0x60
2552
2553
2554 /* Control the compression with mode page 15. Algorithm not changed if zero.
2555
2556 The block descriptors are read and written because Sony SDT-7000 does not
2557 work without this (suggestion from Michael Schaefer <Michael.Schaefer@dlr.de>).
2558 Including block descriptors should not cause any harm to other drives. */
2559
st_compression(struct scsi_tape * STp,int state)2560 static int st_compression(struct scsi_tape * STp, int state)
2561 {
2562 int retval;
2563 int mpoffs; /* Offset to mode page start */
2564 unsigned char *b_data = (STp->buffer)->b_data;
2565
2566 if (STp->ready != ST_READY)
2567 return (-EIO);
2568
2569 /* Read the current page contents */
2570 retval = read_mode_page(STp, COMPRESSION_PAGE, 0);
2571 if (retval) {
2572 DEBC_printk(STp, "Compression mode page not supported.\n");
2573 return (-EIO);
2574 }
2575
2576 mpoffs = MODE_HEADER_LENGTH + b_data[MH_OFF_BDESCS_LENGTH];
2577 DEBC_printk(STp, "Compression state is %d.\n",
2578 (b_data[mpoffs + CP_OFF_DCE_DCC] & DCE_MASK ? 1 : 0));
2579
2580 /* Check if compression can be changed */
2581 if ((b_data[mpoffs + CP_OFF_DCE_DCC] & DCC_MASK) == 0) {
2582 DEBC_printk(STp, "Compression not supported.\n");
2583 return (-EIO);
2584 }
2585
2586 /* Do the change */
2587 if (state) {
2588 b_data[mpoffs + CP_OFF_DCE_DCC] |= DCE_MASK;
2589 if (STp->c_algo != 0)
2590 b_data[mpoffs + CP_OFF_C_ALGO] = STp->c_algo;
2591 }
2592 else {
2593 b_data[mpoffs + CP_OFF_DCE_DCC] &= ~DCE_MASK;
2594 if (STp->c_algo != 0)
2595 b_data[mpoffs + CP_OFF_C_ALGO] = 0; /* no compression */
2596 }
2597
2598 retval = write_mode_page(STp, COMPRESSION_PAGE, 0);
2599 if (retval) {
2600 DEBC_printk(STp, "Compression change failed.\n");
2601 return (-EIO);
2602 }
2603 DEBC_printk(STp, "Compression state changed to %d.\n", state);
2604
2605 STp->compression_changed = 1;
2606 return 0;
2607 }
2608
2609
2610 /* 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)2611 static int do_load_unload(struct scsi_tape *STp, struct file *filp, int load_code)
2612 {
2613 int retval = (-EIO), timeout;
2614 unsigned char cmd[MAX_COMMAND_SIZE];
2615 struct st_partstat *STps;
2616 struct st_request *SRpnt;
2617
2618 if (STp->ready != ST_READY && !load_code) {
2619 if (STp->ready == ST_NO_TAPE)
2620 return (-ENOMEDIUM);
2621 else
2622 return (-EIO);
2623 }
2624
2625 memset(cmd, 0, MAX_COMMAND_SIZE);
2626 cmd[0] = START_STOP;
2627 if (load_code)
2628 cmd[4] |= 1;
2629 /*
2630 * If arg >= 1 && arg <= 6 Enhanced load/unload in HP C1553A
2631 */
2632 if (load_code >= 1 + MT_ST_HPLOADER_OFFSET
2633 && load_code <= 6 + MT_ST_HPLOADER_OFFSET) {
2634 DEBC_printk(STp, " Enhanced %sload slot %2d.\n",
2635 (cmd[4]) ? "" : "un",
2636 load_code - MT_ST_HPLOADER_OFFSET);
2637 cmd[3] = load_code - MT_ST_HPLOADER_OFFSET; /* MediaID field of C1553A */
2638 }
2639 if (STp->immediate) {
2640 cmd[1] = 1; /* Don't wait for completion */
2641 timeout = STp->device->request_queue->rq_timeout;
2642 }
2643 else
2644 timeout = STp->long_timeout;
2645
2646 DEBC(
2647 if (!load_code)
2648 st_printk(ST_DEB_MSG, STp, "Unloading tape.\n");
2649 else
2650 st_printk(ST_DEB_MSG, STp, "Loading tape.\n");
2651 );
2652
2653 SRpnt = st_do_scsi(NULL, STp, cmd, 0, DMA_NONE,
2654 timeout, MAX_RETRIES, 1);
2655 if (!SRpnt)
2656 return (STp->buffer)->syscall_result;
2657
2658 retval = (STp->buffer)->syscall_result;
2659 st_release_request(SRpnt);
2660
2661 if (!retval) { /* SCSI command successful */
2662
2663 if (!load_code) {
2664 STp->rew_at_close = 0;
2665 STp->ready = ST_NO_TAPE;
2666 }
2667 else {
2668 STp->rew_at_close = STp->autorew_dev;
2669 retval = check_tape(STp, filp);
2670 if (retval > 0)
2671 retval = 0;
2672 }
2673 }
2674 else {
2675 STps = &(STp->ps[STp->partition]);
2676 STps->drv_file = STps->drv_block = (-1);
2677 }
2678
2679 return retval;
2680 }
2681
2682 #if DEBUG
2683 #define ST_DEB_FORWARD 0
2684 #define ST_DEB_BACKWARD 1
deb_space_print(struct scsi_tape * STp,int direction,char * units,unsigned char * cmd)2685 static void deb_space_print(struct scsi_tape *STp, int direction, char *units, unsigned char *cmd)
2686 {
2687 s32 sc;
2688
2689 if (!debugging)
2690 return;
2691
2692 sc = sign_extend32(get_unaligned_be24(&cmd[2]), 23);
2693 if (direction)
2694 sc = -sc;
2695 st_printk(ST_DEB_MSG, STp, "Spacing tape %s over %d %s.\n",
2696 direction ? "backward" : "forward", sc, units);
2697 }
2698 #else
2699 #define ST_DEB_FORWARD 0
2700 #define ST_DEB_BACKWARD 1
deb_space_print(struct scsi_tape * STp,int direction,char * units,unsigned char * cmd)2701 static void deb_space_print(struct scsi_tape *STp, int direction, char *units, unsigned char *cmd) {}
2702 #endif
2703
2704
2705 /* Internal ioctl function */
st_int_ioctl(struct scsi_tape * STp,unsigned int cmd_in,unsigned long arg)2706 static int st_int_ioctl(struct scsi_tape *STp, unsigned int cmd_in, unsigned long arg)
2707 {
2708 int timeout;
2709 long ltmp;
2710 int ioctl_result;
2711 int chg_eof = 1;
2712 unsigned char cmd[MAX_COMMAND_SIZE];
2713 struct st_request *SRpnt;
2714 struct st_partstat *STps;
2715 int fileno, blkno, at_sm, undone;
2716 int datalen = 0, direction = DMA_NONE;
2717
2718 WARN_ON(STp->buffer->do_dio != 0);
2719 if (STp->ready != ST_READY) {
2720 if (STp->ready == ST_NO_TAPE)
2721 return (-ENOMEDIUM);
2722 else
2723 return (-EIO);
2724 }
2725 timeout = STp->long_timeout;
2726 STps = &(STp->ps[STp->partition]);
2727 fileno = STps->drv_file;
2728 blkno = STps->drv_block;
2729 at_sm = STps->at_sm;
2730
2731 memset(cmd, 0, MAX_COMMAND_SIZE);
2732 switch (cmd_in) {
2733 case MTFSFM:
2734 chg_eof = 0; /* Changed from the FSF after this */
2735 fallthrough;
2736 case MTFSF:
2737 cmd[0] = SPACE;
2738 cmd[1] = 0x01; /* Space FileMarks */
2739 cmd[2] = (arg >> 16);
2740 cmd[3] = (arg >> 8);
2741 cmd[4] = arg;
2742 deb_space_print(STp, ST_DEB_FORWARD, "filemarks", cmd);
2743 if (fileno >= 0)
2744 fileno += arg;
2745 blkno = 0;
2746 at_sm &= (arg == 0);
2747 break;
2748 case MTBSFM:
2749 chg_eof = 0; /* Changed from the FSF after this */
2750 fallthrough;
2751 case MTBSF:
2752 cmd[0] = SPACE;
2753 cmd[1] = 0x01; /* Space FileMarks */
2754 ltmp = (-arg);
2755 cmd[2] = (ltmp >> 16);
2756 cmd[3] = (ltmp >> 8);
2757 cmd[4] = ltmp;
2758 deb_space_print(STp, ST_DEB_BACKWARD, "filemarks", cmd);
2759 if (fileno >= 0)
2760 fileno -= arg;
2761 blkno = (-1); /* We can't know the block number */
2762 at_sm &= (arg == 0);
2763 break;
2764 case MTFSR:
2765 cmd[0] = SPACE;
2766 cmd[1] = 0x00; /* Space Blocks */
2767 cmd[2] = (arg >> 16);
2768 cmd[3] = (arg >> 8);
2769 cmd[4] = arg;
2770 deb_space_print(STp, ST_DEB_FORWARD, "blocks", cmd);
2771 if (blkno >= 0)
2772 blkno += arg;
2773 at_sm &= (arg == 0);
2774 break;
2775 case MTBSR:
2776 cmd[0] = SPACE;
2777 cmd[1] = 0x00; /* Space Blocks */
2778 ltmp = (-arg);
2779 cmd[2] = (ltmp >> 16);
2780 cmd[3] = (ltmp >> 8);
2781 cmd[4] = ltmp;
2782 deb_space_print(STp, ST_DEB_BACKWARD, "blocks", cmd);
2783 if (blkno >= 0)
2784 blkno -= arg;
2785 at_sm &= (arg == 0);
2786 break;
2787 case MTFSS:
2788 cmd[0] = SPACE;
2789 cmd[1] = 0x04; /* Space Setmarks */
2790 cmd[2] = (arg >> 16);
2791 cmd[3] = (arg >> 8);
2792 cmd[4] = arg;
2793 deb_space_print(STp, ST_DEB_FORWARD, "setmarks", cmd);
2794 if (arg != 0) {
2795 blkno = fileno = (-1);
2796 at_sm = 1;
2797 }
2798 break;
2799 case MTBSS:
2800 cmd[0] = SPACE;
2801 cmd[1] = 0x04; /* Space Setmarks */
2802 ltmp = (-arg);
2803 cmd[2] = (ltmp >> 16);
2804 cmd[3] = (ltmp >> 8);
2805 cmd[4] = ltmp;
2806 deb_space_print(STp, ST_DEB_BACKWARD, "setmarks", cmd);
2807 if (arg != 0) {
2808 blkno = fileno = (-1);
2809 at_sm = 1;
2810 }
2811 break;
2812 case MTWEOF:
2813 case MTWEOFI:
2814 case MTWSM:
2815 if (STp->write_prot)
2816 return (-EACCES);
2817 cmd[0] = WRITE_FILEMARKS;
2818 if (cmd_in == MTWSM)
2819 cmd[1] = 2;
2820 if (cmd_in == MTWEOFI ||
2821 (cmd_in == MTWEOF && STp->immediate_filemark))
2822 cmd[1] |= 1;
2823 cmd[2] = (arg >> 16);
2824 cmd[3] = (arg >> 8);
2825 cmd[4] = arg;
2826 timeout = STp->device->request_queue->rq_timeout;
2827 DEBC(
2828 if (cmd_in != MTWSM)
2829 st_printk(ST_DEB_MSG, STp,
2830 "Writing %d filemarks.\n",
2831 cmd[2] * 65536 +
2832 cmd[3] * 256 +
2833 cmd[4]);
2834 else
2835 st_printk(ST_DEB_MSG, STp,
2836 "Writing %d setmarks.\n",
2837 cmd[2] * 65536 +
2838 cmd[3] * 256 +
2839 cmd[4]);
2840 )
2841 if (fileno >= 0)
2842 fileno += arg;
2843 blkno = 0;
2844 at_sm = (cmd_in == MTWSM);
2845 break;
2846 case MTREW:
2847 cmd[0] = REZERO_UNIT;
2848 if (STp->immediate) {
2849 cmd[1] = 1; /* Don't wait for completion */
2850 timeout = STp->device->request_queue->rq_timeout;
2851 }
2852 DEBC_printk(STp, "Rewinding tape.\n");
2853 fileno = blkno = at_sm = 0;
2854 break;
2855 case MTNOP:
2856 DEBC_printk(STp, "No op on tape.\n");
2857 return 0; /* Should do something ? */
2858 case MTRETEN:
2859 cmd[0] = START_STOP;
2860 if (STp->immediate) {
2861 cmd[1] = 1; /* Don't wait for completion */
2862 timeout = STp->device->request_queue->rq_timeout;
2863 }
2864 cmd[4] = 3;
2865 DEBC_printk(STp, "Retensioning tape.\n");
2866 fileno = blkno = at_sm = 0;
2867 break;
2868 case MTEOM:
2869 if (!STp->fast_mteom) {
2870 /* space to the end of tape */
2871 ioctl_result = st_int_ioctl(STp, MTFSF, 0x7fffff);
2872 fileno = STps->drv_file;
2873 if (STps->eof >= ST_EOD_1)
2874 return 0;
2875 /* The next lines would hide the number of spaced FileMarks
2876 That's why I inserted the previous lines. I had no luck
2877 with detecting EOM with FSF, so we go now to EOM.
2878 Joerg Weule */
2879 } else
2880 fileno = (-1);
2881 cmd[0] = SPACE;
2882 cmd[1] = 3;
2883 DEBC_printk(STp, "Spacing to end of recorded medium.\n");
2884 blkno = -1;
2885 at_sm = 0;
2886 break;
2887 case MTERASE:
2888 if (STp->write_prot)
2889 return (-EACCES);
2890 cmd[0] = ERASE;
2891 cmd[1] = (arg ? 1 : 0); /* Long erase with non-zero argument */
2892 if (STp->immediate) {
2893 cmd[1] |= 2; /* Don't wait for completion */
2894 timeout = STp->device->request_queue->rq_timeout;
2895 }
2896 else
2897 timeout = STp->long_timeout * 8;
2898
2899 DEBC_printk(STp, "Erasing tape.\n");
2900 fileno = blkno = at_sm = 0;
2901 break;
2902 case MTSETBLK: /* Set block length */
2903 case MTSETDENSITY: /* Set tape density */
2904 case MTSETDRVBUFFER: /* Set drive buffering */
2905 case SET_DENS_AND_BLK: /* Set density and block size */
2906 chg_eof = 0;
2907 if (STp->dirty || (STp->buffer)->buffer_bytes != 0)
2908 return (-EIO); /* Not allowed if data in buffer */
2909 if ((cmd_in == MTSETBLK || cmd_in == SET_DENS_AND_BLK) &&
2910 (arg & MT_ST_BLKSIZE_MASK) != 0 &&
2911 STp->max_block > 0 &&
2912 ((arg & MT_ST_BLKSIZE_MASK) < STp->min_block ||
2913 (arg & MT_ST_BLKSIZE_MASK) > STp->max_block)) {
2914 st_printk(KERN_WARNING, STp, "Illegal block size.\n");
2915 return (-EINVAL);
2916 }
2917 cmd[0] = MODE_SELECT;
2918 if ((STp->use_pf & USE_PF))
2919 cmd[1] = MODE_SELECT_PAGE_FORMAT;
2920 cmd[4] = datalen = 12;
2921 direction = DMA_TO_DEVICE;
2922
2923 memset((STp->buffer)->b_data, 0, 12);
2924 if (cmd_in == MTSETDRVBUFFER)
2925 (STp->buffer)->b_data[2] = (arg & 7) << 4;
2926 else
2927 (STp->buffer)->b_data[2] =
2928 STp->drv_buffer << 4;
2929 (STp->buffer)->b_data[3] = 8; /* block descriptor length */
2930 if (cmd_in == MTSETDENSITY) {
2931 (STp->buffer)->b_data[4] = arg;
2932 STp->density_changed = 1; /* At least we tried ;-) */
2933 } else if (cmd_in == SET_DENS_AND_BLK)
2934 (STp->buffer)->b_data[4] = arg >> 24;
2935 else
2936 (STp->buffer)->b_data[4] = STp->density;
2937 if (cmd_in == MTSETBLK || cmd_in == SET_DENS_AND_BLK) {
2938 ltmp = arg & MT_ST_BLKSIZE_MASK;
2939 if (cmd_in == MTSETBLK)
2940 STp->blksize_changed = 1; /* At least we tried ;-) */
2941 } else
2942 ltmp = STp->block_size;
2943 (STp->buffer)->b_data[9] = (ltmp >> 16);
2944 (STp->buffer)->b_data[10] = (ltmp >> 8);
2945 (STp->buffer)->b_data[11] = ltmp;
2946 timeout = STp->device->request_queue->rq_timeout;
2947 DEBC(
2948 if (cmd_in == MTSETBLK || cmd_in == SET_DENS_AND_BLK)
2949 st_printk(ST_DEB_MSG, STp,
2950 "Setting block size to %d bytes.\n",
2951 (STp->buffer)->b_data[9] * 65536 +
2952 (STp->buffer)->b_data[10] * 256 +
2953 (STp->buffer)->b_data[11]);
2954 if (cmd_in == MTSETDENSITY || cmd_in == SET_DENS_AND_BLK)
2955 st_printk(ST_DEB_MSG, STp,
2956 "Setting density code to %x.\n",
2957 (STp->buffer)->b_data[4]);
2958 if (cmd_in == MTSETDRVBUFFER)
2959 st_printk(ST_DEB_MSG, STp,
2960 "Setting drive buffer code to %d.\n",
2961 ((STp->buffer)->b_data[2] >> 4) & 7);
2962 )
2963 break;
2964 default:
2965 return (-ENOSYS);
2966 }
2967
2968 SRpnt = st_do_scsi(NULL, STp, cmd, datalen, direction,
2969 timeout, MAX_RETRIES, 1);
2970 if (!SRpnt)
2971 return (STp->buffer)->syscall_result;
2972
2973 ioctl_result = (STp->buffer)->syscall_result;
2974
2975 if (!ioctl_result) { /* SCSI command successful */
2976 st_release_request(SRpnt);
2977 SRpnt = NULL;
2978 STps->drv_block = blkno;
2979 STps->drv_file = fileno;
2980 STps->at_sm = at_sm;
2981
2982 if (cmd_in == MTBSFM)
2983 ioctl_result = st_int_ioctl(STp, MTFSF, 1);
2984 else if (cmd_in == MTFSFM)
2985 ioctl_result = st_int_ioctl(STp, MTBSF, 1);
2986
2987 if (cmd_in == MTSETBLK || cmd_in == SET_DENS_AND_BLK) {
2988 STp->block_size = arg & MT_ST_BLKSIZE_MASK;
2989 if (STp->block_size != 0) {
2990 (STp->buffer)->buffer_blocks =
2991 (STp->buffer)->buffer_size / STp->block_size;
2992 }
2993 (STp->buffer)->buffer_bytes = (STp->buffer)->read_pointer = 0;
2994 if (cmd_in == SET_DENS_AND_BLK)
2995 STp->density = arg >> MT_ST_DENSITY_SHIFT;
2996 } else if (cmd_in == MTSETDRVBUFFER)
2997 STp->drv_buffer = (arg & 7);
2998 else if (cmd_in == MTSETDENSITY)
2999 STp->density = arg;
3000
3001 if (cmd_in == MTEOM)
3002 STps->eof = ST_EOD;
3003 else if (cmd_in == MTFSF)
3004 STps->eof = ST_FM;
3005 else if (chg_eof)
3006 STps->eof = ST_NOEOF;
3007
3008 if (cmd_in == MTWEOF || cmd_in == MTWEOFI)
3009 STps->rw = ST_IDLE; /* prevent automatic WEOF at close */
3010 } else { /* SCSI command was not completely successful. Don't return
3011 from this block without releasing the SCSI command block! */
3012 struct st_cmdstatus *cmdstatp = &STp->buffer->cmdstat;
3013
3014 if (cmdstatp->flags & SENSE_EOM) {
3015 if (cmd_in != MTBSF && cmd_in != MTBSFM &&
3016 cmd_in != MTBSR && cmd_in != MTBSS)
3017 STps->eof = ST_EOM_OK;
3018 STps->drv_block = 0;
3019 }
3020
3021 if (cmdstatp->remainder_valid)
3022 undone = (int)cmdstatp->uremainder64;
3023 else
3024 undone = 0;
3025
3026 if ((cmd_in == MTWEOF || cmd_in == MTWEOFI) &&
3027 cmdstatp->have_sense &&
3028 (cmdstatp->flags & SENSE_EOM)) {
3029 if (cmdstatp->sense_hdr.sense_key == NO_SENSE ||
3030 cmdstatp->sense_hdr.sense_key == RECOVERED_ERROR) {
3031 ioctl_result = 0; /* EOF(s) written successfully at EOM */
3032 STps->eof = ST_NOEOF;
3033 } else { /* Writing EOF(s) failed */
3034 if (fileno >= 0)
3035 fileno -= undone;
3036 if (undone < arg)
3037 STps->eof = ST_NOEOF;
3038 }
3039 STps->drv_file = fileno;
3040 } else if ((cmd_in == MTFSF) || (cmd_in == MTFSFM)) {
3041 if (fileno >= 0)
3042 STps->drv_file = fileno - undone;
3043 else
3044 STps->drv_file = fileno;
3045 STps->drv_block = -1;
3046 STps->eof = ST_NOEOF;
3047 } else if ((cmd_in == MTBSF) || (cmd_in == MTBSFM)) {
3048 if (arg > 0 && undone < 0) /* Some drives get this wrong */
3049 undone = (-undone);
3050 if (STps->drv_file >= 0)
3051 STps->drv_file = fileno + undone;
3052 STps->drv_block = 0;
3053 STps->eof = ST_NOEOF;
3054 } else if (cmd_in == MTFSR) {
3055 if (cmdstatp->flags & SENSE_FMK) { /* Hit filemark */
3056 if (STps->drv_file >= 0)
3057 STps->drv_file++;
3058 STps->drv_block = 0;
3059 STps->eof = ST_FM;
3060 } else {
3061 if (blkno >= undone)
3062 STps->drv_block = blkno - undone;
3063 else
3064 STps->drv_block = (-1);
3065 STps->eof = ST_NOEOF;
3066 }
3067 } else if (cmd_in == MTBSR) {
3068 if (cmdstatp->flags & SENSE_FMK) { /* Hit filemark */
3069 STps->drv_file--;
3070 STps->drv_block = (-1);
3071 } else {
3072 if (arg > 0 && undone < 0) /* Some drives get this wrong */
3073 undone = (-undone);
3074 if (STps->drv_block >= 0)
3075 STps->drv_block = blkno + undone;
3076 }
3077 STps->eof = ST_NOEOF;
3078 } else if (cmd_in == MTEOM) {
3079 STps->drv_file = (-1);
3080 STps->drv_block = (-1);
3081 STps->eof = ST_EOD;
3082 } else if (cmd_in == MTSETBLK ||
3083 cmd_in == MTSETDENSITY ||
3084 cmd_in == MTSETDRVBUFFER ||
3085 cmd_in == SET_DENS_AND_BLK) {
3086 if (cmdstatp->sense_hdr.sense_key == ILLEGAL_REQUEST &&
3087 !(STp->use_pf & PF_TESTED)) {
3088 /* Try the other possible state of Page Format if not
3089 already tried */
3090 STp->use_pf = (STp->use_pf ^ USE_PF) | PF_TESTED;
3091 st_release_request(SRpnt);
3092 SRpnt = NULL;
3093 return st_int_ioctl(STp, cmd_in, arg);
3094 }
3095 } else if (chg_eof)
3096 STps->eof = ST_NOEOF;
3097
3098 if (cmdstatp->sense_hdr.sense_key == BLANK_CHECK)
3099 STps->eof = ST_EOD;
3100
3101 st_release_request(SRpnt);
3102 SRpnt = NULL;
3103 }
3104
3105 return ioctl_result;
3106 }
3107
3108
3109 /* Get the tape position. If bt == 2, arg points into a kernel space mt_loc
3110 structure. */
3111
get_location(struct scsi_tape * STp,unsigned int * block,int * partition,int logical)3112 static int get_location(struct scsi_tape *STp, unsigned int *block, int *partition,
3113 int logical)
3114 {
3115 int result;
3116 unsigned char scmd[MAX_COMMAND_SIZE];
3117 struct st_request *SRpnt;
3118
3119 if (STp->ready != ST_READY)
3120 return (-EIO);
3121
3122 memset(scmd, 0, MAX_COMMAND_SIZE);
3123 if ((STp->device)->scsi_level < SCSI_2) {
3124 scmd[0] = QFA_REQUEST_BLOCK;
3125 scmd[4] = 3;
3126 } else {
3127 scmd[0] = READ_POSITION;
3128 if (!logical && !STp->scsi2_logical)
3129 scmd[1] = 1;
3130 }
3131 SRpnt = st_do_scsi(NULL, STp, scmd, 20, DMA_FROM_DEVICE,
3132 STp->device->request_queue->rq_timeout,
3133 MAX_READY_RETRIES, 1);
3134 if (!SRpnt)
3135 return (STp->buffer)->syscall_result;
3136
3137 if ((STp->buffer)->syscall_result != 0 ||
3138 (STp->device->scsi_level >= SCSI_2 &&
3139 ((STp->buffer)->b_data[0] & 4) != 0)) {
3140 *block = *partition = 0;
3141 DEBC_printk(STp, " Can't read tape position.\n");
3142 result = (-EIO);
3143 } else {
3144 result = 0;
3145 if ((STp->device)->scsi_level < SCSI_2) {
3146 *block = ((STp->buffer)->b_data[0] << 16)
3147 + ((STp->buffer)->b_data[1] << 8)
3148 + (STp->buffer)->b_data[2];
3149 *partition = 0;
3150 } else {
3151 *block = ((STp->buffer)->b_data[4] << 24)
3152 + ((STp->buffer)->b_data[5] << 16)
3153 + ((STp->buffer)->b_data[6] << 8)
3154 + (STp->buffer)->b_data[7];
3155 *partition = (STp->buffer)->b_data[1];
3156 if (((STp->buffer)->b_data[0] & 0x80) &&
3157 (STp->buffer)->b_data[1] == 0) /* BOP of partition 0 */
3158 STp->ps[0].drv_block = STp->ps[0].drv_file = 0;
3159 }
3160 DEBC_printk(STp, "Got tape pos. blk %d part %d.\n",
3161 *block, *partition);
3162 }
3163 st_release_request(SRpnt);
3164 SRpnt = NULL;
3165
3166 return result;
3167 }
3168
3169
3170 /* Set the tape block and partition. Negative partition means that only the
3171 block should be set in vendor specific way. */
set_location(struct scsi_tape * STp,unsigned int block,int partition,int logical)3172 static int set_location(struct scsi_tape *STp, unsigned int block, int partition,
3173 int logical)
3174 {
3175 struct st_partstat *STps;
3176 int result, p;
3177 unsigned int blk;
3178 int timeout;
3179 unsigned char scmd[MAX_COMMAND_SIZE];
3180 struct st_request *SRpnt;
3181
3182 if (STp->ready != ST_READY)
3183 return (-EIO);
3184 timeout = STp->long_timeout;
3185 STps = &(STp->ps[STp->partition]);
3186
3187 DEBC_printk(STp, "Setting block to %d and partition to %d.\n",
3188 block, partition);
3189 DEB(if (partition < 0)
3190 return (-EIO); )
3191
3192 /* Update the location at the partition we are leaving */
3193 if ((!STp->can_partitions && partition != 0) ||
3194 partition >= ST_NBR_PARTITIONS)
3195 return (-EINVAL);
3196 if (partition != STp->partition) {
3197 if (get_location(STp, &blk, &p, 1))
3198 STps->last_block_valid = 0;
3199 else {
3200 STps->last_block_valid = 1;
3201 STps->last_block_visited = blk;
3202 DEBC_printk(STp, "Visited block %d for "
3203 "partition %d saved.\n",
3204 blk, STp->partition);
3205 }
3206 }
3207
3208 memset(scmd, 0, MAX_COMMAND_SIZE);
3209 if ((STp->device)->scsi_level < SCSI_2) {
3210 scmd[0] = QFA_SEEK_BLOCK;
3211 scmd[2] = (block >> 16);
3212 scmd[3] = (block >> 8);
3213 scmd[4] = block;
3214 scmd[5] = 0;
3215 } else {
3216 scmd[0] = SEEK_10;
3217 scmd[3] = (block >> 24);
3218 scmd[4] = (block >> 16);
3219 scmd[5] = (block >> 8);
3220 scmd[6] = block;
3221 if (!logical && !STp->scsi2_logical)
3222 scmd[1] = 4;
3223 if (STp->partition != partition) {
3224 scmd[1] |= 2;
3225 scmd[8] = partition;
3226 DEBC_printk(STp, "Trying to change partition "
3227 "from %d to %d\n", STp->partition,
3228 partition);
3229 }
3230 }
3231 if (STp->immediate) {
3232 scmd[1] |= 1; /* Don't wait for completion */
3233 timeout = STp->device->request_queue->rq_timeout;
3234 }
3235
3236 SRpnt = st_do_scsi(NULL, STp, scmd, 0, DMA_NONE,
3237 timeout, MAX_READY_RETRIES, 1);
3238 if (!SRpnt)
3239 return (STp->buffer)->syscall_result;
3240
3241 STps->drv_block = STps->drv_file = (-1);
3242 STps->eof = ST_NOEOF;
3243 if ((STp->buffer)->syscall_result != 0) {
3244 result = (-EIO);
3245 if (STp->can_partitions &&
3246 (STp->device)->scsi_level >= SCSI_2 &&
3247 (p = find_partition(STp)) >= 0)
3248 STp->partition = p;
3249 } else {
3250 if (STp->can_partitions) {
3251 STp->partition = partition;
3252 STps = &(STp->ps[partition]);
3253 if (!STps->last_block_valid ||
3254 STps->last_block_visited != block) {
3255 STps->at_sm = 0;
3256 STps->rw = ST_IDLE;
3257 }
3258 } else
3259 STps->at_sm = 0;
3260 if (block == 0)
3261 STps->drv_block = STps->drv_file = 0;
3262 result = 0;
3263 }
3264
3265 st_release_request(SRpnt);
3266 SRpnt = NULL;
3267
3268 return result;
3269 }
3270
3271
3272 /* Find the current partition number for the drive status. Called from open and
3273 returns either partition number of negative error code. */
find_partition(struct scsi_tape * STp)3274 static int find_partition(struct scsi_tape *STp)
3275 {
3276 int i, partition;
3277 unsigned int block;
3278
3279 if ((i = get_location(STp, &block, &partition, 1)) < 0)
3280 return i;
3281 if (partition >= ST_NBR_PARTITIONS)
3282 return (-EIO);
3283 return partition;
3284 }
3285
3286
3287 /* Change the partition if necessary */
switch_partition(struct scsi_tape * STp)3288 static int switch_partition(struct scsi_tape *STp)
3289 {
3290 struct st_partstat *STps;
3291
3292 if (STp->partition == STp->new_partition)
3293 return 0;
3294 STps = &(STp->ps[STp->new_partition]);
3295 if (!STps->last_block_valid)
3296 STps->last_block_visited = 0;
3297 return set_location(STp, STps->last_block_visited, STp->new_partition, 1);
3298 }
3299
3300 /* Functions for reading and writing the medium partition mode page. */
3301
3302 #define PART_PAGE 0x11
3303 #define PART_PAGE_FIXED_LENGTH 8
3304
3305 #define PP_OFF_MAX_ADD_PARTS 2
3306 #define PP_OFF_NBR_ADD_PARTS 3
3307 #define PP_OFF_FLAGS 4
3308 #define PP_OFF_PART_UNITS 6
3309 #define PP_OFF_RESERVED 7
3310
3311 #define PP_BIT_IDP 0x20
3312 #define PP_BIT_FDP 0x80
3313 #define PP_MSK_PSUM_MB 0x10
3314 #define PP_MSK_PSUM_UNITS 0x18
3315 #define PP_MSK_POFM 0x04
3316
3317 /* Get the number of partitions on the tape. As a side effect reads the
3318 mode page into the tape buffer. */
nbr_partitions(struct scsi_tape * STp)3319 static int nbr_partitions(struct scsi_tape *STp)
3320 {
3321 int result;
3322
3323 if (STp->ready != ST_READY)
3324 return (-EIO);
3325
3326 result = read_mode_page(STp, PART_PAGE, 1);
3327
3328 if (result) {
3329 DEBC_printk(STp, "Can't read medium partition page.\n");
3330 result = (-EIO);
3331 } else {
3332 result = (STp->buffer)->b_data[MODE_HEADER_LENGTH +
3333 PP_OFF_NBR_ADD_PARTS] + 1;
3334 DEBC_printk(STp, "Number of partitions %d.\n", result);
3335 }
3336
3337 return result;
3338 }
3339
3340
format_medium(struct scsi_tape * STp,int format)3341 static int format_medium(struct scsi_tape *STp, int format)
3342 {
3343 int result = 0;
3344 int timeout = STp->long_timeout;
3345 unsigned char scmd[MAX_COMMAND_SIZE];
3346 struct st_request *SRpnt;
3347
3348 memset(scmd, 0, MAX_COMMAND_SIZE);
3349 scmd[0] = FORMAT_UNIT;
3350 scmd[2] = format;
3351 if (STp->immediate) {
3352 scmd[1] |= 1; /* Don't wait for completion */
3353 timeout = STp->device->request_queue->rq_timeout;
3354 }
3355 DEBC_printk(STp, "Sending FORMAT MEDIUM\n");
3356 SRpnt = st_do_scsi(NULL, STp, scmd, 0, DMA_NONE,
3357 timeout, MAX_RETRIES, 1);
3358 if (!SRpnt)
3359 result = STp->buffer->syscall_result;
3360 return result;
3361 }
3362
3363
3364 /* Partition the tape into two partitions if size > 0 or one partition if
3365 size == 0.
3366
3367 The block descriptors are read and written because Sony SDT-7000 does not
3368 work without this (suggestion from Michael Schaefer <Michael.Schaefer@dlr.de>).
3369
3370 My HP C1533A drive returns only one partition size field. This is used to
3371 set the size of partition 1. There is no size field for the default partition.
3372 Michael Schaefer's Sony SDT-7000 returns two descriptors and the second is
3373 used to set the size of partition 1 (this is what the SCSI-3 standard specifies).
3374 The following algorithm is used to accommodate both drives: if the number of
3375 partition size fields is greater than the maximum number of additional partitions
3376 in the mode page, the second field is used. Otherwise the first field is used.
3377
3378 For Seagate DDS drives the page length must be 8 when no partitions is defined
3379 and 10 when 1 partition is defined (information from Eric Lee Green). This is
3380 is acceptable also to some other old drives and enforced if the first partition
3381 size field is used for the first additional partition size.
3382
3383 For drives that advertize SCSI-3 or newer, use the SSC-3 methods.
3384 */
partition_tape(struct scsi_tape * STp,int size)3385 static int partition_tape(struct scsi_tape *STp, int size)
3386 {
3387 int result;
3388 int target_partition;
3389 bool scsi3 = STp->device->scsi_level >= SCSI_3, needs_format = false;
3390 int pgo, psd_cnt, psdo;
3391 int psum = PP_MSK_PSUM_MB, units = 0;
3392 unsigned char *bp;
3393
3394 result = read_mode_page(STp, PART_PAGE, 0);
3395 if (result) {
3396 DEBC_printk(STp, "Can't read partition mode page.\n");
3397 return result;
3398 }
3399 target_partition = 1;
3400 if (size < 0) {
3401 target_partition = 0;
3402 size = -size;
3403 }
3404
3405 /* The mode page is in the buffer. Let's modify it and write it. */
3406 bp = (STp->buffer)->b_data;
3407 pgo = MODE_HEADER_LENGTH + bp[MH_OFF_BDESCS_LENGTH];
3408 DEBC_printk(STp, "Partition page length is %d bytes.\n",
3409 bp[pgo + MP_OFF_PAGE_LENGTH] + 2);
3410
3411 psd_cnt = (bp[pgo + MP_OFF_PAGE_LENGTH] + 2 - PART_PAGE_FIXED_LENGTH) / 2;
3412
3413 if (scsi3) {
3414 needs_format = (bp[pgo + PP_OFF_FLAGS] & PP_MSK_POFM) != 0;
3415 if (needs_format && size == 0) {
3416 /* No need to write the mode page when clearing
3417 * partitioning
3418 */
3419 DEBC_printk(STp, "Formatting tape with one partition.\n");
3420 result = format_medium(STp, 0);
3421 goto out;
3422 }
3423 if (needs_format) /* Leave the old value for HP DATs claiming SCSI_3 */
3424 psd_cnt = 2;
3425 if ((bp[pgo + PP_OFF_FLAGS] & PP_MSK_PSUM_UNITS) == PP_MSK_PSUM_UNITS) {
3426 /* Use units scaling for large partitions if the device
3427 * suggests it and no precision lost. Required for IBM
3428 * TS1140/50 drives that don't support MB units.
3429 */
3430 if (size >= 1000 && (size % 1000) == 0) {
3431 size /= 1000;
3432 psum = PP_MSK_PSUM_UNITS;
3433 units = 9; /* GB */
3434 }
3435 }
3436 /* Try it anyway if too large to specify in MB */
3437 if (psum == PP_MSK_PSUM_MB && size >= 65534) {
3438 size /= 1000;
3439 psum = PP_MSK_PSUM_UNITS;
3440 units = 9; /* GB */
3441 }
3442 }
3443
3444 if (size >= 65535 || /* Does not fit into two bytes */
3445 (target_partition == 0 && psd_cnt < 2)) {
3446 result = -EINVAL;
3447 goto out;
3448 }
3449
3450 psdo = pgo + PART_PAGE_FIXED_LENGTH;
3451 /* The second condition is for HP DDS which use only one partition size
3452 * descriptor
3453 */
3454 if (target_partition > 0 &&
3455 (psd_cnt > bp[pgo + PP_OFF_MAX_ADD_PARTS] ||
3456 bp[pgo + PP_OFF_MAX_ADD_PARTS] != 1)) {
3457 bp[psdo] = bp[psdo + 1] = 0xff; /* Rest to partition 0 */
3458 psdo += 2;
3459 }
3460 memset(bp + psdo, 0, bp[pgo + PP_OFF_NBR_ADD_PARTS] * 2);
3461
3462 DEBC_printk(STp, "psd_cnt %d, max.parts %d, nbr_parts %d\n",
3463 psd_cnt, bp[pgo + PP_OFF_MAX_ADD_PARTS],
3464 bp[pgo + PP_OFF_NBR_ADD_PARTS]);
3465
3466 if (size == 0) {
3467 bp[pgo + PP_OFF_NBR_ADD_PARTS] = 0;
3468 if (psd_cnt <= bp[pgo + PP_OFF_MAX_ADD_PARTS])
3469 bp[pgo + MP_OFF_PAGE_LENGTH] = 6;
3470 DEBC_printk(STp, "Formatting tape with one partition.\n");
3471 } else {
3472 bp[psdo] = (size >> 8) & 0xff;
3473 bp[psdo + 1] = size & 0xff;
3474 if (target_partition == 0)
3475 bp[psdo + 2] = bp[psdo + 3] = 0xff;
3476 bp[pgo + 3] = 1;
3477 if (bp[pgo + MP_OFF_PAGE_LENGTH] < 8)
3478 bp[pgo + MP_OFF_PAGE_LENGTH] = 8;
3479 DEBC_printk(STp,
3480 "Formatting tape with two partitions (%i = %d MB).\n",
3481 target_partition, units > 0 ? size * 1000 : size);
3482 }
3483 bp[pgo + PP_OFF_PART_UNITS] = 0;
3484 bp[pgo + PP_OFF_RESERVED] = 0;
3485 if (size != 1 || units != 0) {
3486 bp[pgo + PP_OFF_FLAGS] = PP_BIT_IDP | psum |
3487 (bp[pgo + PP_OFF_FLAGS] & 0x07);
3488 bp[pgo + PP_OFF_PART_UNITS] = units;
3489 } else
3490 bp[pgo + PP_OFF_FLAGS] = PP_BIT_FDP |
3491 (bp[pgo + PP_OFF_FLAGS] & 0x1f);
3492 bp[pgo + MP_OFF_PAGE_LENGTH] = 6 + psd_cnt * 2;
3493
3494 result = write_mode_page(STp, PART_PAGE, 1);
3495
3496 if (!result && needs_format)
3497 result = format_medium(STp, 1);
3498
3499 if (result) {
3500 st_printk(KERN_INFO, STp, "Partitioning of tape failed.\n");
3501 result = (-EIO);
3502 }
3503
3504 out:
3505 return result;
3506 }
3507
3508
3509
3510 /* The ioctl command */
st_ioctl(struct file * file,unsigned int cmd_in,unsigned long arg)3511 static long st_ioctl(struct file *file, unsigned int cmd_in, unsigned long arg)
3512 {
3513 void __user *p = (void __user *)arg;
3514 int i, cmd_nr, cmd_type, bt;
3515 int retval = 0;
3516 unsigned int blk;
3517 bool cmd_mtiocget;
3518 struct scsi_tape *STp = file->private_data;
3519 struct st_modedef *STm;
3520 struct st_partstat *STps;
3521
3522 if (mutex_lock_interruptible(&STp->lock))
3523 return -ERESTARTSYS;
3524
3525 DEB(
3526 if (debugging && !STp->in_use) {
3527 st_printk(ST_DEB_MSG, STp, "Incorrect device.\n");
3528 retval = (-EIO);
3529 goto out;
3530 } ) /* end DEB */
3531
3532 STm = &(STp->modes[STp->current_mode]);
3533 STps = &(STp->ps[STp->partition]);
3534
3535 /*
3536 * If we are in the middle of error recovery, don't let anyone
3537 * else try and use this device. Also, if error recovery fails, it
3538 * may try and take the device offline, in which case all further
3539 * access to the device is prohibited.
3540 */
3541 retval = scsi_ioctl_block_when_processing_errors(STp->device, cmd_in,
3542 file->f_flags & O_NDELAY);
3543 if (retval)
3544 goto out;
3545
3546 cmd_type = _IOC_TYPE(cmd_in);
3547 cmd_nr = _IOC_NR(cmd_in);
3548
3549 if (cmd_type == _IOC_TYPE(MTIOCTOP) && cmd_nr == _IOC_NR(MTIOCTOP)) {
3550 struct mtop mtc;
3551
3552 if (_IOC_SIZE(cmd_in) != sizeof(mtc)) {
3553 retval = (-EINVAL);
3554 goto out;
3555 }
3556
3557 i = copy_from_user(&mtc, p, sizeof(struct mtop));
3558 if (i) {
3559 retval = (-EFAULT);
3560 goto out;
3561 }
3562
3563 if (mtc.mt_op == MTSETDRVBUFFER && !capable(CAP_SYS_ADMIN)) {
3564 st_printk(KERN_WARNING, STp,
3565 "MTSETDRVBUFFER only allowed for root.\n");
3566 retval = (-EPERM);
3567 goto out;
3568 }
3569 if (!STm->defined &&
3570 (mtc.mt_op != MTSETDRVBUFFER &&
3571 (mtc.mt_count & MT_ST_OPTIONS) == 0)) {
3572 retval = (-ENXIO);
3573 goto out;
3574 }
3575
3576 if (!STp->pos_unknown) {
3577
3578 if (STps->eof == ST_FM_HIT) {
3579 if (mtc.mt_op == MTFSF || mtc.mt_op == MTFSFM ||
3580 mtc.mt_op == MTEOM) {
3581 mtc.mt_count -= 1;
3582 if (STps->drv_file >= 0)
3583 STps->drv_file += 1;
3584 } else if (mtc.mt_op == MTBSF || mtc.mt_op == MTBSFM) {
3585 mtc.mt_count += 1;
3586 if (STps->drv_file >= 0)
3587 STps->drv_file += 1;
3588 }
3589 }
3590
3591 if (mtc.mt_op == MTSEEK) {
3592 /* Old position must be restored if partition will be
3593 changed */
3594 i = !STp->can_partitions ||
3595 (STp->new_partition != STp->partition);
3596 } else {
3597 i = mtc.mt_op == MTREW || mtc.mt_op == MTOFFL ||
3598 mtc.mt_op == MTRETEN || mtc.mt_op == MTEOM ||
3599 mtc.mt_op == MTLOCK || mtc.mt_op == MTLOAD ||
3600 mtc.mt_op == MTFSF || mtc.mt_op == MTFSFM ||
3601 mtc.mt_op == MTBSF || mtc.mt_op == MTBSFM ||
3602 mtc.mt_op == MTCOMPRESSION;
3603 }
3604 i = flush_buffer(STp, i);
3605 if (i < 0) {
3606 retval = i;
3607 goto out;
3608 }
3609 if (STps->rw == ST_WRITING &&
3610 (mtc.mt_op == MTREW || mtc.mt_op == MTOFFL ||
3611 mtc.mt_op == MTSEEK ||
3612 mtc.mt_op == MTBSF || mtc.mt_op == MTBSFM)) {
3613 i = st_int_ioctl(STp, MTWEOF, 1);
3614 if (i < 0) {
3615 retval = i;
3616 goto out;
3617 }
3618 if (mtc.mt_op == MTBSF || mtc.mt_op == MTBSFM)
3619 mtc.mt_count++;
3620 STps->rw = ST_IDLE;
3621 }
3622
3623 } else {
3624 /*
3625 * If there was a bus reset, block further access
3626 * to this device. If the user wants to rewind the tape,
3627 * then reset the flag and allow access again.
3628 */
3629 if (mtc.mt_op != MTREW &&
3630 mtc.mt_op != MTOFFL &&
3631 mtc.mt_op != MTLOAD &&
3632 mtc.mt_op != MTRETEN &&
3633 mtc.mt_op != MTERASE &&
3634 mtc.mt_op != MTSEEK &&
3635 mtc.mt_op != MTEOM) {
3636 retval = (-EIO);
3637 goto out;
3638 }
3639 reset_state(STp);
3640 /* remove this when the midlevel properly clears was_reset */
3641 STp->device->was_reset = 0;
3642 }
3643
3644 if (mtc.mt_op != MTNOP && mtc.mt_op != MTSETBLK &&
3645 mtc.mt_op != MTSETDENSITY && mtc.mt_op != MTWSM &&
3646 mtc.mt_op != MTSETDRVBUFFER && mtc.mt_op != MTSETPART)
3647 STps->rw = ST_IDLE; /* Prevent automatic WEOF and fsf */
3648
3649 if (mtc.mt_op == MTOFFL && STp->door_locked != ST_UNLOCKED)
3650 do_door_lock(STp, 0); /* Ignore result! */
3651
3652 if (mtc.mt_op == MTSETDRVBUFFER &&
3653 (mtc.mt_count & MT_ST_OPTIONS) != 0) {
3654 retval = st_set_options(STp, mtc.mt_count);
3655 goto out;
3656 }
3657
3658 if (mtc.mt_op == MTSETPART) {
3659 if (!STp->can_partitions ||
3660 mtc.mt_count < 0 || mtc.mt_count >= ST_NBR_PARTITIONS) {
3661 retval = (-EINVAL);
3662 goto out;
3663 }
3664 if (mtc.mt_count >= STp->nbr_partitions &&
3665 (STp->nbr_partitions = nbr_partitions(STp)) < 0) {
3666 retval = (-EIO);
3667 goto out;
3668 }
3669 if (mtc.mt_count >= STp->nbr_partitions) {
3670 retval = (-EINVAL);
3671 goto out;
3672 }
3673 STp->new_partition = mtc.mt_count;
3674 retval = 0;
3675 goto out;
3676 }
3677
3678 if (mtc.mt_op == MTMKPART) {
3679 if (!STp->can_partitions) {
3680 retval = (-EINVAL);
3681 goto out;
3682 }
3683 i = do_load_unload(STp, file, 1);
3684 if (i < 0) {
3685 retval = i;
3686 goto out;
3687 }
3688 i = partition_tape(STp, mtc.mt_count);
3689 if (i < 0) {
3690 retval = i;
3691 goto out;
3692 }
3693 for (i = 0; i < ST_NBR_PARTITIONS; i++) {
3694 STp->ps[i].rw = ST_IDLE;
3695 STp->ps[i].at_sm = 0;
3696 STp->ps[i].last_block_valid = 0;
3697 }
3698 STp->partition = STp->new_partition = 0;
3699 STp->nbr_partitions = mtc.mt_count != 0 ? 2 : 1;
3700 STps->drv_block = STps->drv_file = 0;
3701 retval = 0;
3702 goto out;
3703 }
3704
3705 if (mtc.mt_op == MTSEEK) {
3706 i = set_location(STp, mtc.mt_count, STp->new_partition, 0);
3707 if (!STp->can_partitions)
3708 STp->ps[0].rw = ST_IDLE;
3709 retval = i;
3710 goto out;
3711 }
3712
3713 if (mtc.mt_op == MTUNLOAD || mtc.mt_op == MTOFFL) {
3714 retval = do_load_unload(STp, file, 0);
3715 goto out;
3716 }
3717
3718 if (mtc.mt_op == MTLOAD) {
3719 retval = do_load_unload(STp, file, max(1, mtc.mt_count));
3720 goto out;
3721 }
3722
3723 if (mtc.mt_op == MTLOCK || mtc.mt_op == MTUNLOCK) {
3724 retval = do_door_lock(STp, (mtc.mt_op == MTLOCK));
3725 goto out;
3726 }
3727
3728 if (STp->can_partitions && STp->ready == ST_READY &&
3729 (i = switch_partition(STp)) < 0) {
3730 retval = i;
3731 goto out;
3732 }
3733
3734 if (mtc.mt_op == MTCOMPRESSION)
3735 retval = st_compression(STp, (mtc.mt_count & 1));
3736 else
3737 retval = st_int_ioctl(STp, mtc.mt_op, mtc.mt_count);
3738 goto out;
3739 }
3740 if (!STm->defined) {
3741 retval = (-ENXIO);
3742 goto out;
3743 }
3744
3745 cmd_mtiocget = cmd_type == _IOC_TYPE(MTIOCGET) && cmd_nr == _IOC_NR(MTIOCGET);
3746
3747 if ((i = flush_buffer(STp, 0)) < 0) {
3748 if (cmd_mtiocget && STp->pos_unknown) {
3749 /* flush fails -> modify status accordingly */
3750 reset_state(STp);
3751 STp->pos_unknown = 1;
3752 } else { /* return error */
3753 retval = i;
3754 goto out;
3755 }
3756 } else { /* flush_buffer succeeds */
3757 if (STp->can_partitions) {
3758 i = switch_partition(STp);
3759 if (i < 0) {
3760 retval = i;
3761 goto out;
3762 }
3763 }
3764 }
3765
3766 if (cmd_mtiocget) {
3767 struct mtget mt_status;
3768
3769 if (_IOC_SIZE(cmd_in) != sizeof(struct mtget)) {
3770 retval = (-EINVAL);
3771 goto out;
3772 }
3773
3774 mt_status.mt_type = STp->tape_type;
3775 mt_status.mt_dsreg =
3776 ((STp->block_size << MT_ST_BLKSIZE_SHIFT) & MT_ST_BLKSIZE_MASK) |
3777 ((STp->density << MT_ST_DENSITY_SHIFT) & MT_ST_DENSITY_MASK);
3778 mt_status.mt_blkno = STps->drv_block;
3779 mt_status.mt_fileno = STps->drv_file;
3780 if (STp->block_size != 0 && mt_status.mt_blkno >= 0) {
3781 if (STps->rw == ST_WRITING)
3782 mt_status.mt_blkno +=
3783 (STp->buffer)->buffer_bytes / STp->block_size;
3784 else if (STps->rw == ST_READING)
3785 mt_status.mt_blkno -=
3786 ((STp->buffer)->buffer_bytes +
3787 STp->block_size - 1) / STp->block_size;
3788 }
3789
3790 mt_status.mt_gstat = 0;
3791 if (STp->drv_write_prot)
3792 mt_status.mt_gstat |= GMT_WR_PROT(0xffffffff);
3793 if (mt_status.mt_blkno == 0) {
3794 if (mt_status.mt_fileno == 0)
3795 mt_status.mt_gstat |= GMT_BOT(0xffffffff);
3796 else
3797 mt_status.mt_gstat |= GMT_EOF(0xffffffff);
3798 }
3799 mt_status.mt_erreg = (STp->recover_reg << MT_ST_SOFTERR_SHIFT);
3800 mt_status.mt_resid = STp->partition;
3801 if (STps->eof == ST_EOM_OK || STps->eof == ST_EOM_ERROR)
3802 mt_status.mt_gstat |= GMT_EOT(0xffffffff);
3803 else if (STps->eof >= ST_EOM_OK)
3804 mt_status.mt_gstat |= GMT_EOD(0xffffffff);
3805 if (STp->density == 1)
3806 mt_status.mt_gstat |= GMT_D_800(0xffffffff);
3807 else if (STp->density == 2)
3808 mt_status.mt_gstat |= GMT_D_1600(0xffffffff);
3809 else if (STp->density == 3)
3810 mt_status.mt_gstat |= GMT_D_6250(0xffffffff);
3811 if (STp->ready == ST_READY)
3812 mt_status.mt_gstat |= GMT_ONLINE(0xffffffff);
3813 if (STp->ready == ST_NO_TAPE)
3814 mt_status.mt_gstat |= GMT_DR_OPEN(0xffffffff);
3815 if (STps->at_sm)
3816 mt_status.mt_gstat |= GMT_SM(0xffffffff);
3817 if (STm->do_async_writes ||
3818 (STm->do_buffer_writes && STp->block_size != 0) ||
3819 STp->drv_buffer != 0)
3820 mt_status.mt_gstat |= GMT_IM_REP_EN(0xffffffff);
3821 if (STp->cleaning_req)
3822 mt_status.mt_gstat |= GMT_CLN(0xffffffff);
3823
3824 retval = put_user_mtget(p, &mt_status);
3825 if (retval)
3826 goto out;
3827
3828 STp->recover_reg = 0; /* Clear after read */
3829 goto out;
3830 } /* End of MTIOCGET */
3831 if (cmd_type == _IOC_TYPE(MTIOCPOS) && cmd_nr == _IOC_NR(MTIOCPOS)) {
3832 struct mtpos mt_pos;
3833 if (_IOC_SIZE(cmd_in) != sizeof(struct mtpos)) {
3834 retval = (-EINVAL);
3835 goto out;
3836 }
3837 if ((i = get_location(STp, &blk, &bt, 0)) < 0) {
3838 retval = i;
3839 goto out;
3840 }
3841 mt_pos.mt_blkno = blk;
3842 retval = put_user_mtpos(p, &mt_pos);
3843 goto out;
3844 }
3845 mutex_unlock(&STp->lock);
3846
3847 switch (cmd_in) {
3848 case SG_IO:
3849 case SCSI_IOCTL_SEND_COMMAND:
3850 case CDROM_SEND_PACKET:
3851 if (!capable(CAP_SYS_RAWIO))
3852 return -EPERM;
3853 break;
3854 default:
3855 break;
3856 }
3857
3858 retval = scsi_ioctl(STp->device, file->f_mode & FMODE_WRITE, cmd_in, p);
3859 if (!retval && cmd_in == SCSI_IOCTL_STOP_UNIT) {
3860 /* unload */
3861 STp->rew_at_close = 0;
3862 STp->ready = ST_NO_TAPE;
3863 }
3864 return retval;
3865
3866 out:
3867 mutex_unlock(&STp->lock);
3868 return retval;
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 /* argument conversion is handled using put_user_mtpos/put_user_mtget */
3875 switch (cmd_in) {
3876 case MTIOCPOS32:
3877 cmd_in = MTIOCPOS;
3878 break;
3879 case MTIOCGET32:
3880 cmd_in = MTIOCGET;
3881 break;
3882 }
3883
3884 return st_ioctl(file, cmd_in, arg);
3885 }
3886 #endif
3887
3888
3889
3890 /* Try to allocate a new tape buffer. Calling function must not hold
3891 dev_arr_lock. */
new_tape_buffer(int max_sg)3892 static struct st_buffer *new_tape_buffer(int max_sg)
3893 {
3894 struct st_buffer *tb;
3895
3896 tb = kzalloc(sizeof(struct st_buffer), GFP_KERNEL);
3897 if (!tb) {
3898 printk(KERN_NOTICE "st: Can't allocate new tape buffer.\n");
3899 return NULL;
3900 }
3901 tb->frp_segs = 0;
3902 tb->use_sg = max_sg;
3903 tb->buffer_size = 0;
3904
3905 tb->reserved_pages = kcalloc(max_sg, sizeof(struct page *),
3906 GFP_KERNEL);
3907 if (!tb->reserved_pages) {
3908 kfree(tb);
3909 return NULL;
3910 }
3911
3912 return tb;
3913 }
3914
3915
3916 /* Try to allocate enough space in the tape buffer */
3917 #define ST_MAX_ORDER 6
3918
enlarge_buffer(struct st_buffer * STbuffer,int new_size)3919 static int enlarge_buffer(struct st_buffer * STbuffer, int new_size)
3920 {
3921 int segs, max_segs, b_size, order, got;
3922 gfp_t priority;
3923
3924 if (new_size <= STbuffer->buffer_size)
3925 return 1;
3926
3927 if (STbuffer->buffer_size <= PAGE_SIZE)
3928 normalize_buffer(STbuffer); /* Avoid extra segment */
3929
3930 max_segs = STbuffer->use_sg;
3931
3932 priority = GFP_KERNEL | __GFP_NOWARN;
3933
3934 if (STbuffer->cleared)
3935 priority |= __GFP_ZERO;
3936
3937 if (STbuffer->frp_segs) {
3938 order = STbuffer->reserved_page_order;
3939 b_size = PAGE_SIZE << order;
3940 } else {
3941 for (b_size = PAGE_SIZE, order = 0;
3942 order < ST_MAX_ORDER &&
3943 max_segs * (PAGE_SIZE << order) < new_size;
3944 order++, b_size *= 2)
3945 ; /* empty */
3946 STbuffer->reserved_page_order = order;
3947 }
3948 if (max_segs * (PAGE_SIZE << order) < new_size) {
3949 if (order == ST_MAX_ORDER)
3950 return 0;
3951 normalize_buffer(STbuffer);
3952 return enlarge_buffer(STbuffer, new_size);
3953 }
3954
3955 for (segs = STbuffer->frp_segs, got = STbuffer->buffer_size;
3956 segs < max_segs && got < new_size;) {
3957 struct page *page;
3958
3959 page = alloc_pages(priority, order);
3960 if (!page) {
3961 DEB(STbuffer->buffer_size = got);
3962 normalize_buffer(STbuffer);
3963 return 0;
3964 }
3965
3966 STbuffer->frp_segs += 1;
3967 got += b_size;
3968 STbuffer->buffer_size = got;
3969 STbuffer->reserved_pages[segs] = page;
3970 segs++;
3971 }
3972 STbuffer->b_data = page_address(STbuffer->reserved_pages[0]);
3973
3974 return 1;
3975 }
3976
3977
3978 /* Make sure that no data from previous user is in the internal buffer */
clear_buffer(struct st_buffer * st_bp)3979 static void clear_buffer(struct st_buffer * st_bp)
3980 {
3981 int i;
3982
3983 for (i=0; i < st_bp->frp_segs; i++)
3984 memset(page_address(st_bp->reserved_pages[i]), 0,
3985 PAGE_SIZE << st_bp->reserved_page_order);
3986 st_bp->cleared = 1;
3987 }
3988
3989
3990 /* Release the extra buffer */
normalize_buffer(struct st_buffer * STbuffer)3991 static void normalize_buffer(struct st_buffer * STbuffer)
3992 {
3993 int i, order = STbuffer->reserved_page_order;
3994
3995 for (i = 0; i < STbuffer->frp_segs; i++) {
3996 __free_pages(STbuffer->reserved_pages[i], order);
3997 STbuffer->buffer_size -= (PAGE_SIZE << order);
3998 }
3999 STbuffer->frp_segs = 0;
4000 STbuffer->sg_segs = 0;
4001 STbuffer->reserved_page_order = 0;
4002 STbuffer->map_data.offset = 0;
4003 }
4004
4005
4006 /* Move data from the user buffer to the tape buffer. Returns zero (success) or
4007 negative error code. */
append_to_buffer(const char __user * ubp,struct st_buffer * st_bp,int do_count)4008 static int append_to_buffer(const char __user *ubp, struct st_buffer * st_bp, int do_count)
4009 {
4010 int i, cnt, res, offset;
4011 int length = PAGE_SIZE << st_bp->reserved_page_order;
4012
4013 for (i = 0, offset = st_bp->buffer_bytes;
4014 i < st_bp->frp_segs && offset >= length; i++)
4015 offset -= length;
4016 if (i == st_bp->frp_segs) { /* Should never happen */
4017 printk(KERN_WARNING "st: append_to_buffer offset overflow.\n");
4018 return (-EIO);
4019 }
4020 for (; i < st_bp->frp_segs && do_count > 0; i++) {
4021 struct page *page = st_bp->reserved_pages[i];
4022 cnt = length - offset < do_count ? length - offset : do_count;
4023 res = copy_from_user(page_address(page) + offset, ubp, cnt);
4024 if (res)
4025 return (-EFAULT);
4026 do_count -= cnt;
4027 st_bp->buffer_bytes += cnt;
4028 ubp += cnt;
4029 offset = 0;
4030 }
4031 if (do_count) /* Should never happen */
4032 return (-EIO);
4033
4034 return 0;
4035 }
4036
4037
4038 /* Move data from the tape buffer to the user buffer. Returns zero (success) or
4039 negative error code. */
from_buffer(struct st_buffer * st_bp,char __user * ubp,int do_count)4040 static int from_buffer(struct st_buffer * st_bp, char __user *ubp, int do_count)
4041 {
4042 int i, cnt, res, offset;
4043 int length = PAGE_SIZE << st_bp->reserved_page_order;
4044
4045 for (i = 0, offset = st_bp->read_pointer;
4046 i < st_bp->frp_segs && offset >= length; i++)
4047 offset -= length;
4048 if (i == st_bp->frp_segs) { /* Should never happen */
4049 printk(KERN_WARNING "st: from_buffer offset overflow.\n");
4050 return (-EIO);
4051 }
4052 for (; i < st_bp->frp_segs && do_count > 0; i++) {
4053 struct page *page = st_bp->reserved_pages[i];
4054 cnt = length - offset < do_count ? length - offset : do_count;
4055 res = copy_to_user(ubp, page_address(page) + offset, cnt);
4056 if (res)
4057 return (-EFAULT);
4058 do_count -= cnt;
4059 st_bp->buffer_bytes -= cnt;
4060 st_bp->read_pointer += cnt;
4061 ubp += cnt;
4062 offset = 0;
4063 }
4064 if (do_count) /* Should never happen */
4065 return (-EIO);
4066
4067 return 0;
4068 }
4069
4070
4071 /* Move data towards start of buffer */
move_buffer_data(struct st_buffer * st_bp,int offset)4072 static void move_buffer_data(struct st_buffer * st_bp, int offset)
4073 {
4074 int src_seg, dst_seg, src_offset = 0, dst_offset;
4075 int count, total;
4076 int length = PAGE_SIZE << st_bp->reserved_page_order;
4077
4078 if (offset == 0)
4079 return;
4080
4081 total=st_bp->buffer_bytes - offset;
4082 for (src_seg=0; src_seg < st_bp->frp_segs; src_seg++) {
4083 src_offset = offset;
4084 if (src_offset < length)
4085 break;
4086 offset -= length;
4087 }
4088
4089 st_bp->buffer_bytes = st_bp->read_pointer = total;
4090 for (dst_seg=dst_offset=0; total > 0; ) {
4091 struct page *dpage = st_bp->reserved_pages[dst_seg];
4092 struct page *spage = st_bp->reserved_pages[src_seg];
4093
4094 count = min(length - dst_offset, length - src_offset);
4095 memmove(page_address(dpage) + dst_offset,
4096 page_address(spage) + src_offset, count);
4097 src_offset += count;
4098 if (src_offset >= length) {
4099 src_seg++;
4100 src_offset = 0;
4101 }
4102 dst_offset += count;
4103 if (dst_offset >= length) {
4104 dst_seg++;
4105 dst_offset = 0;
4106 }
4107 total -= count;
4108 }
4109 }
4110
4111 /* Validate the options from command line or module parameters */
validate_options(void)4112 static void validate_options(void)
4113 {
4114 if (buffer_kbs > 0)
4115 st_fixed_buffer_size = buffer_kbs * ST_KILOBYTE;
4116 if (max_sg_segs >= ST_FIRST_SG)
4117 st_max_sg_segs = max_sg_segs;
4118 }
4119
4120 #ifndef MODULE
4121 /* Set the boot options. Syntax is defined in Documenation/scsi/st.txt.
4122 */
st_setup(char * str)4123 static int __init st_setup(char *str)
4124 {
4125 int i, len, ints[5];
4126 char *stp;
4127
4128 stp = get_options(str, ARRAY_SIZE(ints), ints);
4129
4130 if (ints[0] > 0) {
4131 for (i = 0; i < ints[0] && i < ARRAY_SIZE(parms); i++)
4132 if (parms[i].val)
4133 *parms[i].val = ints[i + 1];
4134 } else {
4135 while (stp != NULL) {
4136 for (i = 0; i < ARRAY_SIZE(parms); i++) {
4137 len = strlen(parms[i].name);
4138 if (!strncmp(stp, parms[i].name, len) &&
4139 (*(stp + len) == ':' || *(stp + len) == '=')) {
4140 if (parms[i].val)
4141 *parms[i].val =
4142 simple_strtoul(stp + len + 1, NULL, 0);
4143 else
4144 printk(KERN_WARNING "st: Obsolete parameter %s\n",
4145 parms[i].name);
4146 break;
4147 }
4148 }
4149 if (i >= ARRAY_SIZE(parms))
4150 printk(KERN_WARNING "st: invalid parameter in '%s'\n",
4151 stp);
4152 stp = strchr(stp, ',');
4153 if (stp)
4154 stp++;
4155 }
4156 }
4157
4158 validate_options();
4159
4160 return 1;
4161 }
4162
4163 __setup("st=", st_setup);
4164
4165 #endif
4166
4167 static const struct file_operations st_fops =
4168 {
4169 .owner = THIS_MODULE,
4170 .read = st_read,
4171 .write = st_write,
4172 .unlocked_ioctl = st_ioctl,
4173 #ifdef CONFIG_COMPAT
4174 .compat_ioctl = st_compat_ioctl,
4175 #endif
4176 .open = st_open,
4177 .flush = st_flush,
4178 .release = st_release,
4179 .llseek = noop_llseek,
4180 };
4181
create_one_cdev(struct scsi_tape * tape,int mode,int rew)4182 static int create_one_cdev(struct scsi_tape *tape, int mode, int rew)
4183 {
4184 int i, error;
4185 dev_t cdev_devno;
4186 struct cdev *cdev;
4187 struct device *dev;
4188 struct st_modedef *STm = &(tape->modes[mode]);
4189 char name[10];
4190 int dev_num = tape->index;
4191
4192 cdev_devno = MKDEV(SCSI_TAPE_MAJOR, TAPE_MINOR(dev_num, mode, rew));
4193
4194 cdev = cdev_alloc();
4195 if (!cdev) {
4196 pr_err("st%d: out of memory. Device not attached.\n", dev_num);
4197 error = -ENOMEM;
4198 goto out;
4199 }
4200 cdev->owner = THIS_MODULE;
4201 cdev->ops = &st_fops;
4202 STm->cdevs[rew] = cdev;
4203
4204 error = cdev_add(cdev, cdev_devno, 1);
4205 if (error) {
4206 pr_err("st%d: Can't add %s-rewind mode %d\n", dev_num,
4207 rew ? "non" : "auto", mode);
4208 pr_err("st%d: Device not attached.\n", dev_num);
4209 goto out_free;
4210 }
4211
4212 i = mode << (4 - ST_NBR_MODE_BITS);
4213 snprintf(name, 10, "%s%s%s", rew ? "n" : "",
4214 tape->name, st_formats[i]);
4215
4216 dev = device_create(&st_sysfs_class, &tape->device->sdev_gendev,
4217 cdev_devno, &tape->modes[mode], "%s", name);
4218 if (IS_ERR(dev)) {
4219 pr_err("st%d: device_create failed\n", dev_num);
4220 error = PTR_ERR(dev);
4221 goto out_free;
4222 }
4223
4224 STm->devs[rew] = dev;
4225
4226 return 0;
4227 out_free:
4228 cdev_del(STm->cdevs[rew]);
4229 out:
4230 STm->cdevs[rew] = NULL;
4231 STm->devs[rew] = NULL;
4232 return error;
4233 }
4234
create_cdevs(struct scsi_tape * tape)4235 static int create_cdevs(struct scsi_tape *tape)
4236 {
4237 int mode, error;
4238 for (mode = 0; mode < ST_NBR_MODES; ++mode) {
4239 error = create_one_cdev(tape, mode, 0);
4240 if (error)
4241 return error;
4242 error = create_one_cdev(tape, mode, 1);
4243 if (error)
4244 return error;
4245 }
4246
4247 return sysfs_create_link(&tape->device->sdev_gendev.kobj,
4248 &tape->modes[0].devs[0]->kobj, "tape");
4249 }
4250
remove_cdevs(struct scsi_tape * tape)4251 static void remove_cdevs(struct scsi_tape *tape)
4252 {
4253 int mode, rew;
4254 sysfs_remove_link(&tape->device->sdev_gendev.kobj, "tape");
4255 for (mode = 0; mode < ST_NBR_MODES; mode++) {
4256 struct st_modedef *STm = &(tape->modes[mode]);
4257 for (rew = 0; rew < 2; rew++) {
4258 if (STm->cdevs[rew])
4259 cdev_del(STm->cdevs[rew]);
4260 if (STm->devs[rew])
4261 device_unregister(STm->devs[rew]);
4262 }
4263 }
4264 }
4265
st_probe(struct device * dev)4266 static int st_probe(struct device *dev)
4267 {
4268 struct scsi_device *SDp = to_scsi_device(dev);
4269 struct scsi_tape *tpnt = NULL;
4270 struct st_modedef *STm;
4271 struct st_partstat *STps;
4272 struct st_buffer *buffer;
4273 int i, error;
4274
4275 if (SDp->type != TYPE_TAPE)
4276 return -ENODEV;
4277 if (st_incompatible(SDp)) {
4278 sdev_printk(KERN_INFO, SDp,
4279 "OnStream tapes are no longer supported;\n");
4280 sdev_printk(KERN_INFO, SDp,
4281 "please mail to linux-scsi@vger.kernel.org.\n");
4282 return -ENODEV;
4283 }
4284
4285 scsi_autopm_get_device(SDp);
4286 i = queue_max_segments(SDp->request_queue);
4287 if (st_max_sg_segs < i)
4288 i = st_max_sg_segs;
4289 buffer = new_tape_buffer(i);
4290 if (buffer == NULL) {
4291 sdev_printk(KERN_ERR, SDp,
4292 "st: Can't allocate new tape buffer. "
4293 "Device not attached.\n");
4294 goto out;
4295 }
4296
4297 tpnt = kzalloc(sizeof(struct scsi_tape), GFP_KERNEL);
4298 if (tpnt == NULL) {
4299 sdev_printk(KERN_ERR, SDp,
4300 "st: Can't allocate device descriptor.\n");
4301 goto out_buffer_free;
4302 }
4303 kref_init(&tpnt->kref);
4304
4305 tpnt->device = SDp;
4306 if (SDp->scsi_level <= 2)
4307 tpnt->tape_type = MT_ISSCSI1;
4308 else
4309 tpnt->tape_type = MT_ISSCSI2;
4310
4311 tpnt->buffer = buffer;
4312 tpnt->buffer->last_SRpnt = NULL;
4313
4314 tpnt->inited = 0;
4315 tpnt->dirty = 0;
4316 tpnt->in_use = 0;
4317 tpnt->drv_buffer = 1; /* Try buffering if no mode sense */
4318 tpnt->use_pf = (SDp->scsi_level >= SCSI_2);
4319 tpnt->density = 0;
4320 tpnt->do_auto_lock = ST_AUTO_LOCK;
4321 tpnt->can_bsr = (SDp->scsi_level > 2 ? 1 : ST_IN_FILE_POS); /* BSR mandatory in SCSI3 */
4322 tpnt->can_partitions = 0;
4323 tpnt->two_fm = ST_TWO_FM;
4324 tpnt->fast_mteom = ST_FAST_MTEOM;
4325 tpnt->scsi2_logical = ST_SCSI2LOGICAL;
4326 tpnt->sili = ST_SILI;
4327 tpnt->immediate = ST_NOWAIT;
4328 tpnt->immediate_filemark = 0;
4329 tpnt->default_drvbuffer = 0xff; /* No forced buffering */
4330 tpnt->partition = 0;
4331 tpnt->new_partition = 0;
4332 tpnt->nbr_partitions = 0;
4333 blk_queue_rq_timeout(tpnt->device->request_queue, ST_TIMEOUT);
4334 tpnt->long_timeout = ST_LONG_TIMEOUT;
4335 tpnt->try_dio = try_direct_io;
4336 tpnt->first_tur = 1;
4337
4338 for (i = 0; i < ST_NBR_MODES; i++) {
4339 STm = &(tpnt->modes[i]);
4340 STm->defined = 0;
4341 STm->sysv = ST_SYSV;
4342 STm->defaults_for_writes = 0;
4343 STm->do_async_writes = ST_ASYNC_WRITES;
4344 STm->do_buffer_writes = ST_BUFFER_WRITES;
4345 STm->do_read_ahead = ST_READ_AHEAD;
4346 STm->default_compression = ST_DONT_TOUCH;
4347 STm->default_blksize = (-1); /* No forced size */
4348 STm->default_density = (-1); /* No forced density */
4349 STm->tape = tpnt;
4350 }
4351
4352 for (i = 0; i < ST_NBR_PARTITIONS; i++) {
4353 STps = &(tpnt->ps[i]);
4354 STps->rw = ST_IDLE;
4355 STps->eof = ST_NOEOF;
4356 STps->at_sm = 0;
4357 STps->last_block_valid = 0;
4358 STps->drv_block = (-1);
4359 STps->drv_file = (-1);
4360 }
4361
4362 tpnt->current_mode = 0;
4363 tpnt->modes[0].defined = 1;
4364
4365 tpnt->density_changed = tpnt->compression_changed =
4366 tpnt->blksize_changed = 0;
4367 mutex_init(&tpnt->lock);
4368
4369 idr_preload(GFP_KERNEL);
4370 spin_lock(&st_index_lock);
4371 error = idr_alloc(&st_index_idr, tpnt, 0, ST_MAX_TAPES + 1, GFP_NOWAIT);
4372 spin_unlock(&st_index_lock);
4373 idr_preload_end();
4374 if (error < 0) {
4375 pr_warn("st: idr allocation failed: %d\n", error);
4376 goto out_free_tape;
4377 }
4378 tpnt->index = error;
4379 sprintf(tpnt->name, "st%d", tpnt->index);
4380 tpnt->stats = kzalloc(sizeof(struct scsi_tape_stats), GFP_KERNEL);
4381 if (tpnt->stats == NULL) {
4382 sdev_printk(KERN_ERR, SDp,
4383 "st: Can't allocate statistics.\n");
4384 goto out_idr_remove;
4385 }
4386
4387 dev_set_drvdata(dev, tpnt);
4388
4389
4390 error = create_cdevs(tpnt);
4391 if (error)
4392 goto out_remove_devs;
4393 scsi_autopm_put_device(SDp);
4394
4395 sdev_printk(KERN_NOTICE, SDp,
4396 "Attached scsi tape %s\n", tpnt->name);
4397 sdev_printk(KERN_INFO, SDp, "%s: try direct i/o: %s (alignment %d B)\n",
4398 tpnt->name, tpnt->try_dio ? "yes" : "no",
4399 queue_dma_alignment(SDp->request_queue) + 1);
4400
4401 return 0;
4402
4403 out_remove_devs:
4404 remove_cdevs(tpnt);
4405 kfree(tpnt->stats);
4406 out_idr_remove:
4407 spin_lock(&st_index_lock);
4408 idr_remove(&st_index_idr, tpnt->index);
4409 spin_unlock(&st_index_lock);
4410 out_free_tape:
4411 kfree(tpnt);
4412 out_buffer_free:
4413 kfree(buffer);
4414 out:
4415 scsi_autopm_put_device(SDp);
4416 return -ENODEV;
4417 };
4418
4419
st_remove(struct device * dev)4420 static int st_remove(struct device *dev)
4421 {
4422 struct scsi_tape *tpnt = dev_get_drvdata(dev);
4423 int index = tpnt->index;
4424
4425 scsi_autopm_get_device(to_scsi_device(dev));
4426 remove_cdevs(tpnt);
4427
4428 mutex_lock(&st_ref_mutex);
4429 kref_put(&tpnt->kref, scsi_tape_release);
4430 mutex_unlock(&st_ref_mutex);
4431 spin_lock(&st_index_lock);
4432 idr_remove(&st_index_idr, index);
4433 spin_unlock(&st_index_lock);
4434 return 0;
4435 }
4436
4437 /**
4438 * scsi_tape_release - Called to free the Scsi_Tape structure
4439 * @kref: pointer to embedded kref
4440 *
4441 * st_ref_mutex must be held entering this routine. Because it is
4442 * called on last put, you should always use the scsi_tape_get()
4443 * scsi_tape_put() helpers which manipulate the semaphore directly
4444 * and never do a direct kref_put().
4445 **/
scsi_tape_release(struct kref * kref)4446 static void scsi_tape_release(struct kref *kref)
4447 {
4448 struct scsi_tape *tpnt = to_scsi_tape(kref);
4449
4450 tpnt->device = NULL;
4451
4452 if (tpnt->buffer) {
4453 normalize_buffer(tpnt->buffer);
4454 kfree(tpnt->buffer->reserved_pages);
4455 kfree(tpnt->buffer);
4456 }
4457
4458 kfree(tpnt->stats);
4459 kfree(tpnt);
4460 return;
4461 }
4462
4463 static const struct class st_sysfs_class = {
4464 .name = "scsi_tape",
4465 .dev_groups = st_dev_groups,
4466 };
4467
init_st(void)4468 static int __init init_st(void)
4469 {
4470 int err;
4471
4472 validate_options();
4473
4474 printk(KERN_INFO "st: Version %s, fixed bufsize %d, s/g segs %d\n",
4475 verstr, st_fixed_buffer_size, st_max_sg_segs);
4476
4477 debugging = (debug_flag > 0) ? debug_flag : NO_DEBUG;
4478 if (debugging) {
4479 printk(KERN_INFO "st: Debugging enabled debug_flag = %d\n",
4480 debugging);
4481 }
4482
4483 err = class_register(&st_sysfs_class);
4484 if (err) {
4485 pr_err("Unable register sysfs class for SCSI tapes\n");
4486 return err;
4487 }
4488
4489 err = register_chrdev_region(MKDEV(SCSI_TAPE_MAJOR, 0),
4490 ST_MAX_TAPE_ENTRIES, "st");
4491 if (err) {
4492 printk(KERN_ERR "Unable to get major %d for SCSI tapes\n",
4493 SCSI_TAPE_MAJOR);
4494 goto err_class;
4495 }
4496
4497 err = scsi_register_driver(&st_template.gendrv);
4498 if (err)
4499 goto err_chrdev;
4500
4501 return 0;
4502
4503 err_chrdev:
4504 unregister_chrdev_region(MKDEV(SCSI_TAPE_MAJOR, 0),
4505 ST_MAX_TAPE_ENTRIES);
4506 err_class:
4507 class_unregister(&st_sysfs_class);
4508 return err;
4509 }
4510
exit_st(void)4511 static void __exit exit_st(void)
4512 {
4513 scsi_unregister_driver(&st_template.gendrv);
4514 unregister_chrdev_region(MKDEV(SCSI_TAPE_MAJOR, 0),
4515 ST_MAX_TAPE_ENTRIES);
4516 class_unregister(&st_sysfs_class);
4517 idr_destroy(&st_index_idr);
4518 printk(KERN_INFO "st: Unloaded.\n");
4519 }
4520
4521 module_init(init_st);
4522 module_exit(exit_st);
4523
4524
4525 /* The sysfs driver interface. Read-only at the moment */
try_direct_io_show(struct device_driver * ddp,char * buf)4526 static ssize_t try_direct_io_show(struct device_driver *ddp, char *buf)
4527 {
4528 return scnprintf(buf, PAGE_SIZE, "%d\n", try_direct_io);
4529 }
4530 static DRIVER_ATTR_RO(try_direct_io);
4531
fixed_buffer_size_show(struct device_driver * ddp,char * buf)4532 static ssize_t fixed_buffer_size_show(struct device_driver *ddp, char *buf)
4533 {
4534 return scnprintf(buf, PAGE_SIZE, "%d\n", st_fixed_buffer_size);
4535 }
4536 static DRIVER_ATTR_RO(fixed_buffer_size);
4537
max_sg_segs_show(struct device_driver * ddp,char * buf)4538 static ssize_t max_sg_segs_show(struct device_driver *ddp, char *buf)
4539 {
4540 return scnprintf(buf, PAGE_SIZE, "%d\n", st_max_sg_segs);
4541 }
4542 static DRIVER_ATTR_RO(max_sg_segs);
4543
version_show(struct device_driver * ddd,char * buf)4544 static ssize_t version_show(struct device_driver *ddd, char *buf)
4545 {
4546 return scnprintf(buf, PAGE_SIZE, "[%s]\n", verstr);
4547 }
4548 static DRIVER_ATTR_RO(version);
4549
4550 #if DEBUG
debug_flag_store(struct device_driver * ddp,const char * buf,size_t count)4551 static ssize_t debug_flag_store(struct device_driver *ddp,
4552 const char *buf, size_t count)
4553 {
4554 /* We only care what the first byte of the data is the rest is unused.
4555 * if it's a '1' we turn on debug and if it's a '0' we disable it. All
4556 * other values have -EINVAL returned if they are passed in.
4557 */
4558 if (count > 0) {
4559 if (buf[0] == '0') {
4560 debugging = NO_DEBUG;
4561 return count;
4562 } else if (buf[0] == '1') {
4563 debugging = 1;
4564 return count;
4565 }
4566 }
4567 return -EINVAL;
4568 }
4569
debug_flag_show(struct device_driver * ddp,char * buf)4570 static ssize_t debug_flag_show(struct device_driver *ddp, char *buf)
4571 {
4572 return scnprintf(buf, PAGE_SIZE, "%d\n", debugging);
4573 }
4574 static DRIVER_ATTR_RW(debug_flag);
4575 #endif
4576
4577 static struct attribute *st_drv_attrs[] = {
4578 &driver_attr_try_direct_io.attr,
4579 &driver_attr_fixed_buffer_size.attr,
4580 &driver_attr_max_sg_segs.attr,
4581 &driver_attr_version.attr,
4582 #if DEBUG
4583 &driver_attr_debug_flag.attr,
4584 #endif
4585 NULL,
4586 };
4587 ATTRIBUTE_GROUPS(st_drv);
4588
4589 /* The sysfs simple class interface */
4590 static ssize_t
defined_show(struct device * dev,struct device_attribute * attr,char * buf)4591 defined_show(struct device *dev, struct device_attribute *attr, char *buf)
4592 {
4593 struct st_modedef *STm = dev_get_drvdata(dev);
4594 ssize_t l = 0;
4595
4596 l = snprintf(buf, PAGE_SIZE, "%d\n", STm->defined);
4597 return l;
4598 }
4599 static DEVICE_ATTR_RO(defined);
4600
4601 static ssize_t
default_blksize_show(struct device * dev,struct device_attribute * attr,char * buf)4602 default_blksize_show(struct device *dev, struct device_attribute *attr,
4603 char *buf)
4604 {
4605 struct st_modedef *STm = dev_get_drvdata(dev);
4606 ssize_t l = 0;
4607
4608 l = snprintf(buf, PAGE_SIZE, "%d\n", STm->default_blksize);
4609 return l;
4610 }
4611 static DEVICE_ATTR_RO(default_blksize);
4612
4613 static ssize_t
default_density_show(struct device * dev,struct device_attribute * attr,char * buf)4614 default_density_show(struct device *dev, struct device_attribute *attr,
4615 char *buf)
4616 {
4617 struct st_modedef *STm = dev_get_drvdata(dev);
4618 ssize_t l = 0;
4619 char *fmt;
4620
4621 fmt = STm->default_density >= 0 ? "0x%02x\n" : "%d\n";
4622 l = snprintf(buf, PAGE_SIZE, fmt, STm->default_density);
4623 return l;
4624 }
4625 static DEVICE_ATTR_RO(default_density);
4626
4627 static ssize_t
default_compression_show(struct device * dev,struct device_attribute * attr,char * buf)4628 default_compression_show(struct device *dev, struct device_attribute *attr,
4629 char *buf)
4630 {
4631 struct st_modedef *STm = dev_get_drvdata(dev);
4632 ssize_t l = 0;
4633
4634 l = snprintf(buf, PAGE_SIZE, "%d\n", STm->default_compression - 1);
4635 return l;
4636 }
4637 static DEVICE_ATTR_RO(default_compression);
4638
4639 static ssize_t
options_show(struct device * dev,struct device_attribute * attr,char * buf)4640 options_show(struct device *dev, struct device_attribute *attr, char *buf)
4641 {
4642 struct st_modedef *STm = dev_get_drvdata(dev);
4643 struct scsi_tape *STp = STm->tape;
4644 int options;
4645 ssize_t l = 0;
4646
4647 options = STm->do_buffer_writes ? MT_ST_BUFFER_WRITES : 0;
4648 options |= STm->do_async_writes ? MT_ST_ASYNC_WRITES : 0;
4649 options |= STm->do_read_ahead ? MT_ST_READ_AHEAD : 0;
4650 DEB( options |= debugging ? MT_ST_DEBUGGING : 0 );
4651 options |= STp->two_fm ? MT_ST_TWO_FM : 0;
4652 options |= STp->fast_mteom ? MT_ST_FAST_MTEOM : 0;
4653 options |= STm->defaults_for_writes ? MT_ST_DEF_WRITES : 0;
4654 options |= STp->can_bsr ? MT_ST_CAN_BSR : 0;
4655 options |= STp->omit_blklims ? MT_ST_NO_BLKLIMS : 0;
4656 options |= STp->can_partitions ? MT_ST_CAN_PARTITIONS : 0;
4657 options |= STp->scsi2_logical ? MT_ST_SCSI2LOGICAL : 0;
4658 options |= STm->sysv ? MT_ST_SYSV : 0;
4659 options |= STp->immediate ? MT_ST_NOWAIT : 0;
4660 options |= STp->immediate_filemark ? MT_ST_NOWAIT_EOF : 0;
4661 options |= STp->sili ? MT_ST_SILI : 0;
4662
4663 l = snprintf(buf, PAGE_SIZE, "0x%08x\n", options);
4664 return l;
4665 }
4666 static DEVICE_ATTR_RO(options);
4667
4668 /* Support for tape stats */
4669
4670 /**
4671 * read_cnt_show - return read count - count of reads made from tape drive
4672 * @dev: struct device
4673 * @attr: attribute structure
4674 * @buf: buffer to return formatted data in
4675 */
read_cnt_show(struct device * dev,struct device_attribute * attr,char * buf)4676 static ssize_t read_cnt_show(struct device *dev,
4677 struct device_attribute *attr, char *buf)
4678 {
4679 struct st_modedef *STm = dev_get_drvdata(dev);
4680
4681 return sprintf(buf, "%lld",
4682 (long long)atomic64_read(&STm->tape->stats->read_cnt));
4683 }
4684 static DEVICE_ATTR_RO(read_cnt);
4685
4686 /**
4687 * read_byte_cnt_show - return read byte count - tape drives
4688 * may use blocks less than 512 bytes this gives the raw byte count of
4689 * of data read from the tape drive.
4690 * @dev: struct device
4691 * @attr: attribute structure
4692 * @buf: buffer to return formatted data in
4693 */
read_byte_cnt_show(struct device * dev,struct device_attribute * attr,char * buf)4694 static ssize_t read_byte_cnt_show(struct device *dev,
4695 struct device_attribute *attr, char *buf)
4696 {
4697 struct st_modedef *STm = dev_get_drvdata(dev);
4698
4699 return sprintf(buf, "%lld",
4700 (long long)atomic64_read(&STm->tape->stats->read_byte_cnt));
4701 }
4702 static DEVICE_ATTR_RO(read_byte_cnt);
4703
4704 /**
4705 * read_ns_show - return read ns - overall time spent waiting on reads in ns.
4706 * @dev: struct device
4707 * @attr: attribute structure
4708 * @buf: buffer to return formatted data in
4709 */
read_ns_show(struct device * dev,struct device_attribute * attr,char * buf)4710 static ssize_t read_ns_show(struct device *dev,
4711 struct device_attribute *attr, char *buf)
4712 {
4713 struct st_modedef *STm = dev_get_drvdata(dev);
4714
4715 return sprintf(buf, "%lld",
4716 (long long)atomic64_read(&STm->tape->stats->tot_read_time));
4717 }
4718 static DEVICE_ATTR_RO(read_ns);
4719
4720 /**
4721 * write_cnt_show - write count - number of user calls
4722 * to write(2) that have written data to tape.
4723 * @dev: struct device
4724 * @attr: attribute structure
4725 * @buf: buffer to return formatted data in
4726 */
write_cnt_show(struct device * dev,struct device_attribute * attr,char * buf)4727 static ssize_t write_cnt_show(struct device *dev,
4728 struct device_attribute *attr, char *buf)
4729 {
4730 struct st_modedef *STm = dev_get_drvdata(dev);
4731
4732 return sprintf(buf, "%lld",
4733 (long long)atomic64_read(&STm->tape->stats->write_cnt));
4734 }
4735 static DEVICE_ATTR_RO(write_cnt);
4736
4737 /**
4738 * write_byte_cnt_show - write byte count - raw count of
4739 * bytes written to tape.
4740 * @dev: struct device
4741 * @attr: attribute structure
4742 * @buf: buffer to return formatted data in
4743 */
write_byte_cnt_show(struct device * dev,struct device_attribute * attr,char * buf)4744 static ssize_t write_byte_cnt_show(struct device *dev,
4745 struct device_attribute *attr, char *buf)
4746 {
4747 struct st_modedef *STm = dev_get_drvdata(dev);
4748
4749 return sprintf(buf, "%lld",
4750 (long long)atomic64_read(&STm->tape->stats->write_byte_cnt));
4751 }
4752 static DEVICE_ATTR_RO(write_byte_cnt);
4753
4754 /**
4755 * write_ns_show - write ns - number of nanoseconds waiting on write
4756 * requests to complete.
4757 * @dev: struct device
4758 * @attr: attribute structure
4759 * @buf: buffer to return formatted data in
4760 */
write_ns_show(struct device * dev,struct device_attribute * attr,char * buf)4761 static ssize_t write_ns_show(struct device *dev,
4762 struct device_attribute *attr, char *buf)
4763 {
4764 struct st_modedef *STm = dev_get_drvdata(dev);
4765
4766 return sprintf(buf, "%lld",
4767 (long long)atomic64_read(&STm->tape->stats->tot_write_time));
4768 }
4769 static DEVICE_ATTR_RO(write_ns);
4770
4771 /**
4772 * in_flight_show - number of I/Os currently in flight -
4773 * in most cases this will be either 0 or 1. It may be higher if someone
4774 * has also issued other SCSI commands such as via an ioctl.
4775 * @dev: struct device
4776 * @attr: attribute structure
4777 * @buf: buffer to return formatted data in
4778 */
in_flight_show(struct device * dev,struct device_attribute * attr,char * buf)4779 static ssize_t in_flight_show(struct device *dev,
4780 struct device_attribute *attr, char *buf)
4781 {
4782 struct st_modedef *STm = dev_get_drvdata(dev);
4783
4784 return sprintf(buf, "%lld",
4785 (long long)atomic64_read(&STm->tape->stats->in_flight));
4786 }
4787 static DEVICE_ATTR_RO(in_flight);
4788
4789 /**
4790 * io_ns_show - io wait ns - this is the number of ns spent
4791 * waiting on all I/O to complete. This includes tape movement commands
4792 * such as rewinding, seeking to end of file or tape, it also includes
4793 * read and write. To determine the time spent on tape movement
4794 * subtract the read and write ns from this value.
4795 * @dev: struct device
4796 * @attr: attribute structure
4797 * @buf: buffer to return formatted data in
4798 */
io_ns_show(struct device * dev,struct device_attribute * attr,char * buf)4799 static ssize_t io_ns_show(struct device *dev,
4800 struct device_attribute *attr, char *buf)
4801 {
4802 struct st_modedef *STm = dev_get_drvdata(dev);
4803
4804 return sprintf(buf, "%lld",
4805 (long long)atomic64_read(&STm->tape->stats->tot_io_time));
4806 }
4807 static DEVICE_ATTR_RO(io_ns);
4808
4809 /**
4810 * other_cnt_show - other io count - this is the number of
4811 * I/O requests other than read and write requests.
4812 * Typically these are tape movement requests but will include driver
4813 * tape movement. This includes only requests issued by the st driver.
4814 * @dev: struct device
4815 * @attr: attribute structure
4816 * @buf: buffer to return formatted data in
4817 */
other_cnt_show(struct device * dev,struct device_attribute * attr,char * buf)4818 static ssize_t other_cnt_show(struct device *dev,
4819 struct device_attribute *attr, char *buf)
4820 {
4821 struct st_modedef *STm = dev_get_drvdata(dev);
4822
4823 return sprintf(buf, "%lld",
4824 (long long)atomic64_read(&STm->tape->stats->other_cnt));
4825 }
4826 static DEVICE_ATTR_RO(other_cnt);
4827
4828 /**
4829 * resid_cnt_show - A count of the number of times we get a residual
4830 * count - this should indicate someone issuing reads larger than the
4831 * block size on tape.
4832 * @dev: struct device
4833 * @attr: attribute structure
4834 * @buf: buffer to return formatted data in
4835 */
resid_cnt_show(struct device * dev,struct device_attribute * attr,char * buf)4836 static ssize_t resid_cnt_show(struct device *dev,
4837 struct device_attribute *attr, char *buf)
4838 {
4839 struct st_modedef *STm = dev_get_drvdata(dev);
4840
4841 return sprintf(buf, "%lld",
4842 (long long)atomic64_read(&STm->tape->stats->resid_cnt));
4843 }
4844 static DEVICE_ATTR_RO(resid_cnt);
4845
4846 static struct attribute *st_dev_attrs[] = {
4847 &dev_attr_defined.attr,
4848 &dev_attr_default_blksize.attr,
4849 &dev_attr_default_density.attr,
4850 &dev_attr_default_compression.attr,
4851 &dev_attr_options.attr,
4852 NULL,
4853 };
4854
4855 static struct attribute *st_stats_attrs[] = {
4856 &dev_attr_read_cnt.attr,
4857 &dev_attr_read_byte_cnt.attr,
4858 &dev_attr_read_ns.attr,
4859 &dev_attr_write_cnt.attr,
4860 &dev_attr_write_byte_cnt.attr,
4861 &dev_attr_write_ns.attr,
4862 &dev_attr_in_flight.attr,
4863 &dev_attr_io_ns.attr,
4864 &dev_attr_other_cnt.attr,
4865 &dev_attr_resid_cnt.attr,
4866 NULL,
4867 };
4868
4869 static struct attribute_group stats_group = {
4870 .name = "stats",
4871 .attrs = st_stats_attrs,
4872 };
4873
4874 static struct attribute_group st_group = {
4875 .attrs = st_dev_attrs,
4876 };
4877
4878 static const struct attribute_group *st_dev_groups[] = {
4879 &st_group,
4880 &stats_group,
4881 NULL,
4882 };
4883
4884 /* 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)4885 static int sgl_map_user_pages(struct st_buffer *STbp,
4886 const unsigned int max_pages, unsigned long uaddr,
4887 size_t count, int rw)
4888 {
4889 unsigned long end = (uaddr + count + PAGE_SIZE - 1) >> PAGE_SHIFT;
4890 unsigned long start = uaddr >> PAGE_SHIFT;
4891 const int nr_pages = end - start;
4892 int res, i;
4893 struct page **pages;
4894 struct rq_map_data *mdata = &STbp->map_data;
4895
4896 /* User attempted Overflow! */
4897 if ((uaddr + count) < uaddr)
4898 return -EINVAL;
4899
4900 /* Too big */
4901 if (nr_pages > max_pages)
4902 return -ENOMEM;
4903
4904 /* Hmm? */
4905 if (count == 0)
4906 return 0;
4907
4908 pages = kmalloc_array(max_pages, sizeof(*pages), GFP_KERNEL);
4909 if (pages == NULL)
4910 return -ENOMEM;
4911
4912 /* Try to fault in all of the necessary pages */
4913 /* rw==READ means read from drive, write into memory area */
4914 res = pin_user_pages_fast(uaddr, nr_pages, rw == READ ? FOLL_WRITE : 0,
4915 pages);
4916
4917 /* Errors and no page mapped should return here */
4918 if (res < nr_pages)
4919 goto out_unmap;
4920
4921 for (i=0; i < nr_pages; i++) {
4922 /* FIXME: flush superflous for rw==READ,
4923 * probably wrong function for rw==WRITE
4924 */
4925 flush_dcache_page(pages[i]);
4926 }
4927
4928 mdata->offset = uaddr & ~PAGE_MASK;
4929 STbp->mapped_pages = pages;
4930
4931 return nr_pages;
4932 out_unmap:
4933 if (res > 0) {
4934 unpin_user_pages(pages, res);
4935 res = 0;
4936 }
4937 kfree(pages);
4938 return res;
4939 }
4940
4941
4942 /* And unmap them... */
sgl_unmap_user_pages(struct st_buffer * STbp,const unsigned int nr_pages,int dirtied)4943 static int sgl_unmap_user_pages(struct st_buffer *STbp,
4944 const unsigned int nr_pages, int dirtied)
4945 {
4946 /* FIXME: cache flush missing for rw==READ */
4947 unpin_user_pages_dirty_lock(STbp->mapped_pages, nr_pages, dirtied);
4948
4949 kfree(STbp->mapped_pages);
4950 STbp->mapped_pages = NULL;
4951
4952 return 0;
4953 }
4954