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[SCSI] qla4xxx: bug fixes
[linux-2.6-block.git] / drivers / scsi / st.c
CommitLineData
1da177e4
LT		 1/*
2 SCSI Tape Driver for Linux version 1.1 and newer. See the accompanying
3 file Documentation/scsi/st.txt for more information.
4
5 History:
6 Rewritten from Dwayne Forsyth's SCSI tape driver by Kai Makisara.
7 Contribution and ideas from several people including (in alphabetical
8 order) Klaus Ehrenfried, Eugene Exarevsky, Eric Lee Green, Wolfgang Denk,
9 Steve Hirsch, Andreas Koppenh"ofer, Michael Leodolter, Eyal Lebedinsky,
10 Michael Schaefer, J"org Weule, and Eric Youngdale.
11
42252854 12 Copyright 1992 - 2006 Kai Makisara
1da177e4
LT		 13 email Kai.Makisara@kolumbus.fi
14
15 Some small formal changes - aeb, 950809
16
17 Last modified: 18-JAN-1998 Richard Gooch <rgooch@atnf.csiro.au> Devfs support
18 */
19
42252854 20static const char *verstr = "20061107";
1da177e4
LT		 21
22#include <linux/module.h>
23
24#include <linux/fs.h>
25#include <linux/kernel.h>
26#include <linux/sched.h>
27#include <linux/mm.h>
28#include <linux/init.h>
29#include <linux/string.h>
30#include <linux/errno.h>
31#include <linux/mtio.h>
16c4b3e2 32#include <linux/cdrom.h>
1da177e4
LT		 33#include <linux/ioctl.h>
34#include <linux/fcntl.h>
35#include <linux/spinlock.h>
36#include <linux/blkdev.h>
37#include <linux/moduleparam.h>
1da177e4
LT		 38#include <linux/cdev.h>
39#include <linux/delay.h>
0b950672 40#include <linux/mutex.h>
1da177e4
LT		 41
42#include <asm/uaccess.h>
43#include <asm/dma.h>
44#include <asm/system.h>
45
46#include <scsi/scsi.h>
47#include <scsi/scsi_dbg.h>
48#include <scsi/scsi_device.h>
49#include <scsi/scsi_driver.h>
50#include <scsi/scsi_eh.h>
51#include <scsi/scsi_host.h>
52#include <scsi/scsi_ioctl.h>
16c4b3e2 53#include <scsi/sg.h>
1da177e4
LT		 54
55
56/* The driver prints some debugging information on the console if DEBUG
57 is defined and non-zero. */
58#define DEBUG 0
59
60#if DEBUG
61/* The message level for the debug messages is currently set to KERN_NOTICE
62 so that people can easily see the messages. Later when the debugging messages
63 in the drivers are more widely classified, this may be changed to KERN_DEBUG. */
64#define ST_DEB_MSG KERN_NOTICE
65#define DEB(a) a
66#define DEBC(a) if (debugging) { a ; }
67#else
68#define DEB(a)
69#define DEBC(a)
70#endif
71
72#define ST_KILOBYTE 1024
73
74#include "st_options.h"
75#include "st.h"
76
77static int buffer_kbs;
78static int max_sg_segs;
79static int try_direct_io = TRY_DIRECT_IO;
80static int try_rdio = 1;
81static int try_wdio = 1;
82
83static int st_dev_max;
84static int st_nr_dev;
85
d253878b 86static struct class *st_sysfs_class;
1da177e4
LT		 87
88MODULE_AUTHOR("Kai Makisara");
f018fa55 89MODULE_DESCRIPTION("SCSI tape (st) driver");
1da177e4 90MODULE_LICENSE("GPL");
f018fa55 91MODULE_ALIAS_CHARDEV_MAJOR(SCSI_TAPE_MAJOR);
1da177e4
LT		 92
93/* Set 'perm' (4th argument) to 0 to disable module_param's definition
94 * of sysfs parameters (which module_param doesn't yet support).
95 * Sysfs parameters defined explicitly later.
96 */
97module_param_named(buffer_kbs, buffer_kbs, int, 0);
98MODULE_PARM_DESC(buffer_kbs, "Default driver buffer size for fixed block mode (KB; 32)");
99module_param_named(max_sg_segs, max_sg_segs, int, 0);
100MODULE_PARM_DESC(max_sg_segs, "Maximum number of scatter/gather segments to use (256)");
101module_param_named(try_direct_io, try_direct_io, int, 0);
102MODULE_PARM_DESC(try_direct_io, "Try direct I/O between user buffer and tape drive (1)");
103
104/* Extra parameters for testing */
105module_param_named(try_rdio, try_rdio, int, 0);
106MODULE_PARM_DESC(try_rdio, "Try direct read i/o when possible");
107module_param_named(try_wdio, try_wdio, int, 0);
108MODULE_PARM_DESC(try_wdio, "Try direct write i/o when possible");
109
110#ifndef MODULE
111static int write_threshold_kbs; /* retained for compatibility */
112static struct st_dev_parm {
113 char *name;
114 int *val;
115} parms[] __initdata = {
116 {
117 "buffer_kbs", &buffer_kbs
118 },
119 { /* Retained for compatibility with 2.4 */
120 "write_threshold_kbs", &write_threshold_kbs
121 },
122 {
123 "max_sg_segs", NULL
124 },
125 {
126 "try_direct_io", &try_direct_io
127 }
128};
129#endif
130
131/* Restrict the number of modes so that names for all are assigned */
132#if ST_NBR_MODES > 16
133#error "Maximum number of modes is 16"
134#endif
135/* Bit reversed order to get same names for same minors with all
136 mode counts */
0ad78200 137static const char *st_formats[] = {
1da177e4
LT		 138 "", "r", "k", "s", "l", "t", "o", "u",
139 "m", "v", "p", "x", "a", "y", "q", "z"};
140
141/* The default definitions have been moved to st_options.h */
142
143#define ST_FIXED_BUFFER_SIZE (ST_FIXED_BUFFER_BLOCKS * ST_KILOBYTE)
144
145/* The buffer size should fit into the 24 bits for length in the
146 6-byte SCSI read and write commands. */
147#if ST_FIXED_BUFFER_SIZE >= (2 << 24 - 1)
148#error "Buffer size should not exceed (2 << 24 - 1) bytes!"
149#endif
150
151static int debugging = DEBUG;
152
153#define MAX_RETRIES 0
154#define MAX_WRITE_RETRIES 0
155#define MAX_READY_RETRIES 0
156#define NO_TAPE NOT_READY
157
158#define ST_TIMEOUT (900 * HZ)
159#define ST_LONG_TIMEOUT (14000 * HZ)
160
161/* Remove mode bits and auto-rewind bit (7) */
162#define TAPE_NR(x) ( ((iminor(x) & ~255) >> (ST_NBR_MODE_BITS + 1)) | \
163 (iminor(x) & ~(-1 << ST_MODE_SHIFT)) )
164#define TAPE_MODE(x) ((iminor(x) & ST_MODE_MASK) >> ST_MODE_SHIFT)
165
166/* Construct the minor number from the device (d), mode (m), and non-rewind (n) data */
167#define TAPE_MINOR(d, m, n) (((d & ~(255 >> (ST_NBR_MODE_BITS + 1))) << (ST_NBR_MODE_BITS + 1)) | \
168 (d & (255 >> (ST_NBR_MODE_BITS + 1))) | (m << ST_MODE_SHIFT) | ((n != 0) << 7) )
169
170/* Internal ioctl to set both density (uppermost 8 bits) and blocksize (lower
171 24 bits) */
172#define SET_DENS_AND_BLK 0x10001
173
174static DEFINE_RWLOCK(st_dev_arr_lock);
175
176static int st_fixed_buffer_size = ST_FIXED_BUFFER_SIZE;
177static int st_max_sg_segs = ST_MAX_SG;
178
179static struct scsi_tape **scsi_tapes = NULL;
180
181static int modes_defined;
182
183static struct st_buffer *new_tape_buffer(int, int, int);
184static int enlarge_buffer(struct st_buffer *, int, int);
185static void normalize_buffer(struct st_buffer *);
186static int append_to_buffer(const char __user *, struct st_buffer *, int);
187static int from_buffer(struct st_buffer *, char __user *, int);
188static void move_buffer_data(struct st_buffer *, int);
189static void buf_to_sg(struct st_buffer *, unsigned int);
190
1da177e4
LT		 191static int sgl_map_user_pages(struct scatterlist *, const unsigned int,
192 unsigned long, size_t, int);
193static int sgl_unmap_user_pages(struct scatterlist *, const unsigned int, int);
194
195static int st_probe(struct device *);
196static int st_remove(struct device *);
1da177e4 197
13026a6b 198static int do_create_driverfs_files(void);
1da177e4 199static void do_remove_driverfs_files(void);
13026a6b 200static int do_create_class_files(struct scsi_tape *, int, int);
1da177e4
LT		 201
202static struct scsi_driver st_template = {
203 .owner = THIS_MODULE,
204 .gendrv = {
205 .name = "st",
206 .probe = st_probe,
207 .remove = st_remove,
208 },
1da177e4
LT		 209};
210
211static int st_compression(struct scsi_tape *, int);
212
213static int find_partition(struct scsi_tape *);
214static int switch_partition(struct scsi_tape *);
215
216static int st_int_ioctl(struct scsi_tape *, unsigned int, unsigned long);
217
f03a5670
KM		 218static void scsi_tape_release(struct kref *);
219
220#define to_scsi_tape(obj) container_of(obj, struct scsi_tape, kref)
221
0b950672 222static DEFINE_MUTEX(st_ref_mutex);
f03a5670 223
1da177e4
LT		 224\f
225#include "osst_detect.h"
226#ifndef SIGS_FROM_OSST
227#define SIGS_FROM_OSST \
228 {"OnStream", "SC-", "", "osst"}, \
229 {"OnStream", "DI-", "", "osst"}, \
230 {"OnStream", "DP-", "", "osst"}, \
231 {"OnStream", "USB", "", "osst"}, \
232 {"OnStream", "FW-", "", "osst"}
233#endif
234
f03a5670
KM		 235static struct scsi_tape *scsi_tape_get(int dev)
236{
237 struct scsi_tape *STp = NULL;
238
0b950672 239 mutex_lock(&st_ref_mutex);
f03a5670
KM		 240 write_lock(&st_dev_arr_lock);
241
242 if (dev < st_dev_max && scsi_tapes != NULL)
243 STp = scsi_tapes[dev];
244 if (!STp) goto out;
245
246 kref_get(&STp->kref);
247
248 if (!STp->device)
249 goto out_put;
250
251 if (scsi_device_get(STp->device))
252 goto out_put;
253
254 goto out;
255
256out_put:
257 kref_put(&STp->kref, scsi_tape_release);
258 STp = NULL;
259out:
260 write_unlock(&st_dev_arr_lock);
0b950672 261 mutex_unlock(&st_ref_mutex);
f03a5670
KM		 262 return STp;
263}
264
265static void scsi_tape_put(struct scsi_tape *STp)
266{
267 struct scsi_device *sdev = STp->device;
268
0b950672 269 mutex_lock(&st_ref_mutex);
f03a5670
KM		 270 kref_put(&STp->kref, scsi_tape_release);
271 scsi_device_put(sdev);
0b950672 272 mutex_unlock(&st_ref_mutex);
f03a5670
KM		 273}
274
1da177e4
LT		 275struct st_reject_data {
276 char *vendor;
277 char *model;
278 char *rev;
279 char *driver_hint; /* Name of the correct driver, NULL if unknown */
280};
281
282static struct st_reject_data reject_list[] = {
283 /* {"XXX", "Yy-", "", NULL}, example */
284 SIGS_FROM_OSST,
285 {NULL, }};
286
287/* If the device signature is on the list of incompatible drives, the
288 function returns a pointer to the name of the correct driver (if known) */
289static char * st_incompatible(struct scsi_device* SDp)
290{
291 struct st_reject_data *rp;
292
293 for (rp=&(reject_list[0]); rp->vendor != NULL; rp++)
294 if (!strncmp(rp->vendor, SDp->vendor, strlen(rp->vendor)) &&
295 !strncmp(rp->model, SDp->model, strlen(rp->model)) &&
296 !strncmp(rp->rev, SDp->rev, strlen(rp->rev))) {
297 if (rp->driver_hint)
298 return rp->driver_hint;
299 else
300 return "unknown";
301 }
302 return NULL;
303}
304\f
305
306static inline char *tape_name(struct scsi_tape *tape)
307{
308 return tape->disk->disk_name;
309}
310
311
8b05b773 312static void st_analyze_sense(struct st_request *SRpnt, struct st_cmdstatus *s)
1da177e4
LT		 313{
314 const u8 *ucp;
8b05b773 315 const u8 *sense = SRpnt->sense;
1da177e4 316
8b05b773
MC		 317 s->have_sense = scsi_normalize_sense(SRpnt->sense,
318 SCSI_SENSE_BUFFERSIZE, &s->sense_hdr);
1da177e4
LT		 319 s->flags = 0;
320
321 if (s->have_sense) {
322 s->deferred = 0;
323 s->remainder_valid =
324 scsi_get_sense_info_fld(sense, SCSI_SENSE_BUFFERSIZE, &s->uremainder64);
325 switch (sense[0] & 0x7f) {
326 case 0x71:
327 s->deferred = 1;
328 case 0x70:
329 s->fixed_format = 1;
330 s->flags = sense[2] & 0xe0;
331 break;
332 case 0x73:
333 s->deferred = 1;
334 case 0x72:
335 s->fixed_format = 0;
336 ucp = scsi_sense_desc_find(sense, SCSI_SENSE_BUFFERSIZE, 4);
337 s->flags = ucp ? (ucp[3] & 0xe0) : 0;
338 break;
339 }
340 }
341}
342
343
344/* Convert the result to success code */
8b05b773 345static int st_chk_result(struct scsi_tape *STp, struct st_request * SRpnt)
1da177e4 346{
8b05b773 347 int result = SRpnt->result;
1da177e4
LT		 348 u8 scode;
349 DEB(const char *stp;)
350 char *name = tape_name(STp);
351 struct st_cmdstatus *cmdstatp;
352
353 if (!result)
354 return 0;
355
356 cmdstatp = &STp->buffer->cmdstat;
f03a5670 357 st_analyze_sense(SRpnt, cmdstatp);
1da177e4
LT		 358
359 if (cmdstatp->have_sense)
360 scode = STp->buffer->cmdstat.sense_hdr.sense_key;
361 else
362 scode = 0;
363
364 DEB(
365 if (debugging) {
8b05b773 366 printk(ST_DEB_MSG "%s: Error: %x, cmd: %x %x %x %x %x %x\n",
1da177e4 367 name, result,
8b05b773
MC		 368 SRpnt->cmd[0], SRpnt->cmd[1], SRpnt->cmd[2],
369 SRpnt->cmd[3], SRpnt->cmd[4], SRpnt->cmd[5]);
1da177e4 370 if (cmdstatp->have_sense)
4e73ea7b 371 __scsi_print_sense(name, SRpnt->sense, SCSI_SENSE_BUFFERSIZE);
1da177e4
LT		 372 } ) /* end DEB */
373 if (!debugging) { /* Abnormal conditions for tape */
374 if (!cmdstatp->have_sense)
375 printk(KERN_WARNING
376 "%s: Error %x (sugg. bt 0x%x, driver bt 0x%x, host bt 0x%x).\n",
377 name, result, suggestion(result),
378 driver_byte(result) & DRIVER_MASK, host_byte(result));
379 else if (cmdstatp->have_sense &&
380 scode != NO_SENSE &&
381 scode != RECOVERED_ERROR &&
382 /* scode != UNIT_ATTENTION && */
383 scode != BLANK_CHECK &&
384 scode != VOLUME_OVERFLOW &&
8b05b773
MC		 385 SRpnt->cmd[0] != MODE_SENSE &&
386 SRpnt->cmd[0] != TEST_UNIT_READY) {
4e73ea7b
LT		 387
388 __scsi_print_sense(name, SRpnt->sense, SCSI_SENSE_BUFFERSIZE);
1da177e4
LT		 389 }
390 }
391
392 if (cmdstatp->fixed_format &&
393 STp->cln_mode >= EXTENDED_SENSE_START) { /* Only fixed format sense */
394 if (STp->cln_sense_value)
8b05b773 395 STp->cleaning_req |= ((SRpnt->sense[STp->cln_mode] &
1da177e4
LT		 396 STp->cln_sense_mask) == STp->cln_sense_value);
397 else
8b05b773 398 STp->cleaning_req |= ((SRpnt->sense[STp->cln_mode] &
1da177e4
LT		 399 STp->cln_sense_mask) != 0);
400 }
401 if (cmdstatp->have_sense &&
402 cmdstatp->sense_hdr.asc == 0 && cmdstatp->sense_hdr.ascq == 0x17)
403 STp->cleaning_req = 1; /* ASC and ASCQ => cleaning requested */
404
405 STp->pos_unknown |= STp->device->was_reset;
406
407 if (cmdstatp->have_sense &&
408 scode == RECOVERED_ERROR
409#if ST_RECOVERED_WRITE_FATAL
8b05b773
MC		 410 && SRpnt->cmd[0] != WRITE_6
411 && SRpnt->cmd[0] != WRITE_FILEMARKS
1da177e4
LT		 412#endif
413 ) {
414 STp->recover_count++;
415 STp->recover_reg++;
416
417 DEB(
418 if (debugging) {
8b05b773 419 if (SRpnt->cmd[0] == READ_6)
1da177e4 420 stp = "read";
8b05b773 421 else if (SRpnt->cmd[0] == WRITE_6)
1da177e4
LT		 422 stp = "write";
423 else
424 stp = "ioctl";
425 printk(ST_DEB_MSG "%s: Recovered %s error (%d).\n", name, stp,
426 STp->recover_count);
427 } ) /* end DEB */
428
429 if (cmdstatp->flags == 0)
430 return 0;
431 }
432 return (-EIO);
433}
434
435
436/* Wakeup from interrupt */
8b05b773 437static void st_sleep_done(void *data, char *sense, int result, int resid)
1da177e4 438{
8b05b773
MC		 439 struct st_request *SRpnt = data;
440 struct scsi_tape *STp = SRpnt->stp;
1da177e4 441
8b05b773
MC		 442 memcpy(SRpnt->sense, sense, SCSI_SENSE_BUFFERSIZE);
443 (STp->buffer)->cmdstat.midlevel_result = SRpnt->result = result;
1da177e4
LT		 444 DEB( STp->write_pending = 0; )
445
8b05b773
MC		 446 if (SRpnt->waiting)
447 complete(SRpnt->waiting);
448}
449
450static struct st_request *st_allocate_request(void)
451{
452 return kzalloc(sizeof(struct st_request), GFP_KERNEL);
453}
454
455static void st_release_request(struct st_request *streq)
456{
457 kfree(streq);
1da177e4
LT		 458}
459
460/* Do the scsi command. Waits until command performed if do_wait is true.
461 Otherwise write_behind_check() is used to check that the command
462 has finished. */
8b05b773
MC		 463static struct st_request *
464st_do_scsi(struct st_request * SRpnt, struct scsi_tape * STp, unsigned char *cmd,
1da177e4
LT		 465 int bytes, int direction, int timeout, int retries, int do_wait)
466{
f03a5670 467 struct completion *waiting;
1da177e4 468
f03a5670
KM		 469 /* if async, make sure there's no command outstanding */
470 if (!do_wait && ((STp->buffer)->last_SRpnt)) {
471 printk(KERN_ERR "%s: Async command already active.\n",
472 tape_name(STp));
473 if (signal_pending(current))
474 (STp->buffer)->syscall_result = (-EINTR);
475 else
476 (STp->buffer)->syscall_result = (-EBUSY);
477 return NULL;
478 }
479
1da177e4 480 if (SRpnt == NULL) {
8b05b773 481 SRpnt = st_allocate_request();
1da177e4
LT		 482 if (SRpnt == NULL) {
483 DEBC( printk(KERN_ERR "%s: Can't get SCSI request.\n",
484 tape_name(STp)); );
485 if (signal_pending(current))
486 (STp->buffer)->syscall_result = (-EINTR);
487 else
488 (STp->buffer)->syscall_result = (-EBUSY);
489 return NULL;
490 }
8b05b773 491 SRpnt->stp = STp;
1da177e4
LT		 492 }
493
f03a5670
KM		 494 /* If async IO, set last_SRpnt. This ptr tells write_behind_check
495 which IO is outstanding. It's nulled out when the IO completes. */
496 if (!do_wait)
497 (STp->buffer)->last_SRpnt = SRpnt;
498
499 waiting = &STp->wait;
500 init_completion(waiting);
8b05b773 501 SRpnt->waiting = waiting;
1da177e4 502
8b05b773
MC		 503 if (!STp->buffer->do_dio)
504 buf_to_sg(STp->buffer, bytes);
1da177e4 505
8b05b773
MC		 506 memcpy(SRpnt->cmd, cmd, sizeof(SRpnt->cmd));
507 STp->buffer->cmdstat.have_sense = 0;
508 STp->buffer->syscall_result = 0;
509
bb1d1073 510 if (scsi_execute_async(STp->device, cmd, COMMAND_SIZE(cmd[0]), direction,
8b05b773 511 &((STp->buffer)->sg[0]), bytes, (STp->buffer)->sg_segs,
787926b1 512 timeout, retries, SRpnt, st_sleep_done, GFP_KERNEL)) {
8b05b773
MC		 513 /* could not allocate the buffer or request was too large */
514 (STp->buffer)->syscall_result = (-EBUSY);
787926b1
KM		 515 (STp->buffer)->last_SRpnt = NULL;
516 }
8b05b773 517 else if (do_wait) {
f03a5670 518 wait_for_completion(waiting);
8b05b773 519 SRpnt->waiting = NULL;
1da177e4
LT		 520 (STp->buffer)->syscall_result = st_chk_result(STp, SRpnt);
521 }
8b05b773 522
1da177e4
LT		 523 return SRpnt;
524}
525
526
527/* Handle the write-behind checking (waits for completion). Returns -ENOSPC if
528 write has been correct but EOM early warning reached, -EIO if write ended in
529 error or zero if write successful. Asynchronous writes are used only in
530 variable block mode. */
531static int write_behind_check(struct scsi_tape * STp)
532{
533 int retval = 0;
534 struct st_buffer *STbuffer;
535 struct st_partstat *STps;
536 struct st_cmdstatus *cmdstatp;
8b05b773 537 struct st_request *SRpnt;
1da177e4
LT		 538
539 STbuffer = STp->buffer;
540 if (!STbuffer->writing)
541 return 0;
542
543 DEB(
544 if (STp->write_pending)
545 STp->nbr_waits++;
546 else
547 STp->nbr_finished++;
548 ) /* end DEB */
549
550 wait_for_completion(&(STp->wait));
f03a5670
KM		 551 SRpnt = STbuffer->last_SRpnt;
552 STbuffer->last_SRpnt = NULL;
8b05b773 553 SRpnt->waiting = NULL;
1da177e4 554
f03a5670 555 (STp->buffer)->syscall_result = st_chk_result(STp, SRpnt);
8b05b773 556 st_release_request(SRpnt);
1da177e4
LT		 557
558 STbuffer->buffer_bytes -= STbuffer->writing;
559 STps = &(STp->ps[STp->partition]);
560 if (STps->drv_block >= 0) {
561 if (STp->block_size == 0)
562 STps->drv_block++;
563 else
564 STps->drv_block += STbuffer->writing / STp->block_size;
565 }
566
567 cmdstatp = &STbuffer->cmdstat;
568 if (STbuffer->syscall_result) {
569 retval = -EIO;
570 if (cmdstatp->have_sense && !cmdstatp->deferred &&
571 (cmdstatp->flags & SENSE_EOM) &&
572 (cmdstatp->sense_hdr.sense_key == NO_SENSE ||
573 cmdstatp->sense_hdr.sense_key == RECOVERED_ERROR)) {
574 /* EOM at write-behind, has all data been written? */
575 if (!cmdstatp->remainder_valid ||
576 cmdstatp->uremainder64 == 0)
577 retval = -ENOSPC;
578 }
579 if (retval == -EIO)
580 STps->drv_block = -1;
581 }
582 STbuffer->writing = 0;
583
584 DEB(if (debugging && retval)
585 printk(ST_DEB_MSG "%s: Async write error %x, return value %d.\n",
586 tape_name(STp), STbuffer->cmdstat.midlevel_result, retval);) /* end DEB */
587
588 return retval;
589}
590
591
592/* Step over EOF if it has been inadvertently crossed (ioctl not used because
593 it messes up the block number). */
594static int cross_eof(struct scsi_tape * STp, int forward)
595{
8b05b773 596 struct st_request *SRpnt;
1da177e4
LT		 597 unsigned char cmd[MAX_COMMAND_SIZE];
598
599 cmd[0] = SPACE;
600 cmd[1] = 0x01; /* Space FileMarks */
601 if (forward) {
602 cmd[2] = cmd[3] = 0;
603 cmd[4] = 1;
604 } else
605 cmd[2] = cmd[3] = cmd[4] = 0xff; /* -1 filemarks */
606 cmd[5] = 0;
607
608 DEBC(printk(ST_DEB_MSG "%s: Stepping over filemark %s.\n",
609 tape_name(STp), forward ? "forward" : "backward"));
610
611 SRpnt = st_do_scsi(NULL, STp, cmd, 0, DMA_NONE,
612 STp->device->timeout, MAX_RETRIES, 1);
613 if (!SRpnt)
614 return (STp->buffer)->syscall_result;
615
8b05b773 616 st_release_request(SRpnt);
1da177e4
LT		 617 SRpnt = NULL;
618
619 if ((STp->buffer)->cmdstat.midlevel_result != 0)
620 printk(KERN_ERR "%s: Stepping over filemark %s failed.\n",
621 tape_name(STp), forward ? "forward" : "backward");
622
623 return (STp->buffer)->syscall_result;
624}
625
626
627/* Flush the write buffer (never need to write if variable blocksize). */
628static int flush_write_buffer(struct scsi_tape * STp)
629{
630 int offset, transfer, blks;
631 int result;
632 unsigned char cmd[MAX_COMMAND_SIZE];
8b05b773 633 struct st_request *SRpnt;
1da177e4
LT		 634 struct st_partstat *STps;
635
636 result = write_behind_check(STp);
637 if (result)
638 return result;
639
640 result = 0;
641 if (STp->dirty == 1) {
642
643 offset = (STp->buffer)->buffer_bytes;
644 transfer = ((offset + STp->block_size - 1) /
645 STp->block_size) * STp->block_size;
646 DEBC(printk(ST_DEB_MSG "%s: Flushing %d bytes.\n",
647 tape_name(STp), transfer));
648
649 memset((STp->buffer)->b_data + offset, 0, transfer - offset);
650
651 memset(cmd, 0, MAX_COMMAND_SIZE);
652 cmd[0] = WRITE_6;
653 cmd[1] = 1;
654 blks = transfer / STp->block_size;
655 cmd[2] = blks >> 16;
656 cmd[3] = blks >> 8;
657 cmd[4] = blks;
658
659 SRpnt = st_do_scsi(NULL, STp, cmd, transfer, DMA_TO_DEVICE,
660 STp->device->timeout, MAX_WRITE_RETRIES, 1);
661 if (!SRpnt)
662 return (STp->buffer)->syscall_result;
663
664 STps = &(STp->ps[STp->partition]);
665 if ((STp->buffer)->syscall_result != 0) {
666 struct st_cmdstatus *cmdstatp = &STp->buffer->cmdstat;
667
668 if (cmdstatp->have_sense && !cmdstatp->deferred &&
669 (cmdstatp->flags & SENSE_EOM) &&
670 (cmdstatp->sense_hdr.sense_key == NO_SENSE ||
671 cmdstatp->sense_hdr.sense_key == RECOVERED_ERROR) &&
672 (!cmdstatp->remainder_valid ||
673 cmdstatp->uremainder64 == 0)) { /* All written at EOM early warning */
674 STp->dirty = 0;
675 (STp->buffer)->buffer_bytes = 0;
676 if (STps->drv_block >= 0)
677 STps->drv_block += blks;
678 result = (-ENOSPC);
679 } else {
680 printk(KERN_ERR "%s: Error on flush.\n",
681 tape_name(STp));
682 STps->drv_block = (-1);
683 result = (-EIO);
684 }
685 } else {
686 if (STps->drv_block >= 0)
687 STps->drv_block += blks;
688 STp->dirty = 0;
689 (STp->buffer)->buffer_bytes = 0;
690 }
8b05b773 691 st_release_request(SRpnt);
1da177e4
LT		 692 SRpnt = NULL;
693 }
694 return result;
695}
696
697
698/* Flush the tape buffer. The tape will be positioned correctly unless
699 seek_next is true. */
700static int flush_buffer(struct scsi_tape *STp, int seek_next)
701{
702 int backspace, result;
703 struct st_buffer *STbuffer;
704 struct st_partstat *STps;
705
706 STbuffer = STp->buffer;
707
708 /*
709 * If there was a bus reset, block further access
710 * to this device.
711 */
712 if (STp->pos_unknown)
713 return (-EIO);
714
715 if (STp->ready != ST_READY)
716 return 0;
717 STps = &(STp->ps[STp->partition]);
718 if (STps->rw == ST_WRITING) /* Writing */
719 return flush_write_buffer(STp);
720
721 if (STp->block_size == 0)
722 return 0;
723
724 backspace = ((STp->buffer)->buffer_bytes +
725 (STp->buffer)->read_pointer) / STp->block_size -
726 ((STp->buffer)->read_pointer + STp->block_size - 1) /
727 STp->block_size;
728 (STp->buffer)->buffer_bytes = 0;
729 (STp->buffer)->read_pointer = 0;
730 result = 0;
731 if (!seek_next) {
732 if (STps->eof == ST_FM_HIT) {
733 result = cross_eof(STp, 0); /* Back over the EOF hit */
734 if (!result)
735 STps->eof = ST_NOEOF;
736 else {
737 if (STps->drv_file >= 0)
738 STps->drv_file++;
739 STps->drv_block = 0;
740 }
741 }
742 if (!result && backspace > 0)
743 result = st_int_ioctl(STp, MTBSR, backspace);
744 } else if (STps->eof == ST_FM_HIT) {
745 if (STps->drv_file >= 0)
746 STps->drv_file++;
747 STps->drv_block = 0;
748 STps->eof = ST_NOEOF;
749 }
750 return result;
751
752}
753\f
754/* Set the mode parameters */
755static int set_mode_densblk(struct scsi_tape * STp, struct st_modedef * STm)
756{
757 int set_it = 0;
758 unsigned long arg;
759 char *name = tape_name(STp);
760
761 if (!STp->density_changed &&
762 STm->default_density >= 0 &&
763 STm->default_density != STp->density) {
764 arg = STm->default_density;
765 set_it = 1;
766 } else
767 arg = STp->density;
768 arg <<= MT_ST_DENSITY_SHIFT;
769 if (!STp->blksize_changed &&
770 STm->default_blksize >= 0 &&
771 STm->default_blksize != STp->block_size) {
772 arg |= STm->default_blksize;
773 set_it = 1;
774 } else
775 arg |= STp->block_size;
776 if (set_it &&
777 st_int_ioctl(STp, SET_DENS_AND_BLK, arg)) {
778 printk(KERN_WARNING
779 "%s: Can't set default block size to %d bytes and density %x.\n",
780 name, STm->default_blksize, STm->default_density);
781 if (modes_defined)
782 return (-EINVAL);
783 }
784 return 0;
785}
786
787
8b05b773 788/* Lock or unlock the drive door. Don't use when st_request allocated. */
1da177e4
LT		 789static int do_door_lock(struct scsi_tape * STp, int do_lock)
790{
791 int retval, cmd;
792 DEB(char *name = tape_name(STp);)
793
794
795 cmd = do_lock ? SCSI_IOCTL_DOORLOCK : SCSI_IOCTL_DOORUNLOCK;
796 DEBC(printk(ST_DEB_MSG "%s: %socking drive door.\n", name,
797 do_lock ? "L" : "Unl"));
798 retval = scsi_ioctl(STp->device, cmd, NULL);
799 if (!retval) {
800 STp->door_locked = do_lock ? ST_LOCKED_EXPLICIT : ST_UNLOCKED;
801 }
802 else {
803 STp->door_locked = ST_LOCK_FAILS;
804 }
805 return retval;
806}
807
808
809/* Set the internal state after reset */
810static void reset_state(struct scsi_tape *STp)
811{
812 int i;
813 struct st_partstat *STps;
814
815 STp->pos_unknown = 0;
816 for (i = 0; i < ST_NBR_PARTITIONS; i++) {
817 STps = &(STp->ps[i]);
818 STps->rw = ST_IDLE;
819 STps->eof = ST_NOEOF;
820 STps->at_sm = 0;
821 STps->last_block_valid = 0;
822 STps->drv_block = -1;
823 STps->drv_file = -1;
824 }
825 if (STp->can_partitions) {
826 STp->partition = find_partition(STp);
827 if (STp->partition < 0)
828 STp->partition = 0;
829 STp->new_partition = STp->partition;
830 }
831}
832\f
833/* Test if the drive is ready. Returns either one of the codes below or a negative system
834 error code. */
835#define CHKRES_READY 0
836#define CHKRES_NEW_SESSION 1
837#define CHKRES_NOT_READY 2
838#define CHKRES_NO_TAPE 3
839
840#define MAX_ATTENTIONS 10
841
842static int test_ready(struct scsi_tape *STp, int do_wait)
843{
844 int attentions, waits, max_wait, scode;
845 int retval = CHKRES_READY, new_session = 0;
846 unsigned char cmd[MAX_COMMAND_SIZE];
8b05b773 847 struct st_request *SRpnt = NULL;
1da177e4
LT		 848 struct st_cmdstatus *cmdstatp = &STp->buffer->cmdstat;
849
850 max_wait = do_wait ? ST_BLOCK_SECONDS : 0;
851
852 for (attentions=waits=0; ; ) {
853 memset((void *) &cmd[0], 0, MAX_COMMAND_SIZE);
854 cmd[0] = TEST_UNIT_READY;
855 SRpnt = st_do_scsi(SRpnt, STp, cmd, 0, DMA_NONE,
856 STp->long_timeout, MAX_READY_RETRIES, 1);
857
858 if (!SRpnt) {
859 retval = (STp->buffer)->syscall_result;
860 break;
861 }
862
863 if (cmdstatp->have_sense) {
864
865 scode = cmdstatp->sense_hdr.sense_key;
866
867 if (scode == UNIT_ATTENTION) { /* New media? */
868 new_session = 1;
869 if (attentions < MAX_ATTENTIONS) {
870 attentions++;
871 continue;
872 }
873 else {
874 retval = (-EIO);
875 break;
876 }
877 }
878
879 if (scode == NOT_READY) {
880 if (waits < max_wait) {
881 if (msleep_interruptible(1000)) {
882 retval = (-EINTR);
883 break;
884 }
885 waits++;
886 continue;
887 }
888 else {
889 if ((STp->device)->scsi_level >= SCSI_2 &&
890 cmdstatp->sense_hdr.asc == 0x3a) /* Check ASC */
891 retval = CHKRES_NO_TAPE;
892 else
893 retval = CHKRES_NOT_READY;
894 break;
895 }
896 }
897 }
898
899 retval = (STp->buffer)->syscall_result;
900 if (!retval)
901 retval = new_session ? CHKRES_NEW_SESSION : CHKRES_READY;
902 break;
903 }
904
905 if (SRpnt != NULL)
8b05b773 906 st_release_request(SRpnt);
1da177e4
LT		 907 return retval;
908}
909
910
911/* See if the drive is ready and gather information about the tape. Return values:
912 < 0 negative error code from errno.h
913 0 drive ready
914 1 drive not ready (possibly no tape)
915*/
916static int check_tape(struct scsi_tape *STp, struct file *filp)
917{
918 int i, retval, new_session = 0, do_wait;
919 unsigned char cmd[MAX_COMMAND_SIZE], saved_cleaning;
920 unsigned short st_flags = filp->f_flags;
8b05b773 921 struct st_request *SRpnt = NULL;
1da177e4
LT		 922 struct st_modedef *STm;
923 struct st_partstat *STps;
924 char *name = tape_name(STp);
7ac6207b 925 struct inode *inode = filp->f_path.dentry->d_inode;
1da177e4
LT		 926 int mode = TAPE_MODE(inode);
927
928 STp->ready = ST_READY;
929
930 if (mode != STp->current_mode) {
931 DEBC(printk(ST_DEB_MSG "%s: Mode change from %d to %d.\n",
932 name, STp->current_mode, mode));
933 new_session = 1;
934 STp->current_mode = mode;
935 }
936 STm = &(STp->modes[STp->current_mode]);
937
938 saved_cleaning = STp->cleaning_req;
939 STp->cleaning_req = 0;
940
941 do_wait = ((filp->f_flags & O_NONBLOCK) == 0);
942 retval = test_ready(STp, do_wait);
943
944 if (retval < 0)
945 goto err_out;
946
947 if (retval == CHKRES_NEW_SESSION) {
948 STp->pos_unknown = 0;
949 STp->partition = STp->new_partition = 0;
950 if (STp->can_partitions)
951 STp->nbr_partitions = 1; /* This guess will be updated later
952 if necessary */
953 for (i = 0; i < ST_NBR_PARTITIONS; i++) {
954 STps = &(STp->ps[i]);
955 STps->rw = ST_IDLE;
956 STps->eof = ST_NOEOF;
957 STps->at_sm = 0;
958 STps->last_block_valid = 0;
959 STps->drv_block = 0;
960 STps->drv_file = 0;
961 }
962 new_session = 1;
963 }
964 else {
965 STp->cleaning_req |= saved_cleaning;
966
967 if (retval == CHKRES_NOT_READY || retval == CHKRES_NO_TAPE) {
968 if (retval == CHKRES_NO_TAPE)
969 STp->ready = ST_NO_TAPE;
970 else
971 STp->ready = ST_NOT_READY;
972
973 STp->density = 0; /* Clear the erroneous "residue" */
974 STp->write_prot = 0;
975 STp->block_size = 0;
976 STp->ps[0].drv_file = STp->ps[0].drv_block = (-1);
977 STp->partition = STp->new_partition = 0;
978 STp->door_locked = ST_UNLOCKED;
979 return CHKRES_NOT_READY;
980 }
981 }
982
983 if (STp->omit_blklims)
984 STp->min_block = STp->max_block = (-1);
985 else {
986 memset((void *) &cmd[0], 0, MAX_COMMAND_SIZE);
987 cmd[0] = READ_BLOCK_LIMITS;
988
989 SRpnt = st_do_scsi(SRpnt, STp, cmd, 6, DMA_FROM_DEVICE,
990 STp->device->timeout, MAX_READY_RETRIES, 1);
991 if (!SRpnt) {
992 retval = (STp->buffer)->syscall_result;
993 goto err_out;
994 }
995
8b05b773 996 if (!SRpnt->result && !STp->buffer->cmdstat.have_sense) {
1da177e4
LT		 997 STp->max_block = ((STp->buffer)->b_data[1] << 16) |
998 ((STp->buffer)->b_data[2] << 8) | (STp->buffer)->b_data[3];
999 STp->min_block = ((STp->buffer)->b_data[4] << 8) |
1000 (STp->buffer)->b_data[5];
1001 if ( DEB( debugging || ) !STp->inited)
42252854 1002 printk(KERN_INFO
1da177e4
LT		 1003 "%s: Block limits %d - %d bytes.\n", name,
1004 STp->min_block, STp->max_block);
1005 } else {
1006 STp->min_block = STp->max_block = (-1);
1007 DEBC(printk(ST_DEB_MSG "%s: Can't read block limits.\n",
1008 name));
1009 }
1010 }
1011
1012 memset((void *) &cmd[0], 0, MAX_COMMAND_SIZE);
1013 cmd[0] = MODE_SENSE;
1014 cmd[4] = 12;
1015
1016 SRpnt = st_do_scsi(SRpnt, STp, cmd, 12, DMA_FROM_DEVICE,
1017 STp->device->timeout, MAX_READY_RETRIES, 1);
1018 if (!SRpnt) {
1019 retval = (STp->buffer)->syscall_result;
1020 goto err_out;
1021 }
1022
1023 if ((STp->buffer)->syscall_result != 0) {
1024 DEBC(printk(ST_DEB_MSG "%s: No Mode Sense.\n", name));
1025 STp->block_size = ST_DEFAULT_BLOCK; /* Educated guess (?) */
1026 (STp->buffer)->syscall_result = 0; /* Prevent error propagation */
1027 STp->drv_write_prot = 0;
1028 } else {
1029 DEBC(printk(ST_DEB_MSG
1030 "%s: Mode sense. Length %d, medium %x, WBS %x, BLL %d\n",
1031 name,
1032 (STp->buffer)->b_data[0], (STp->buffer)->b_data[1],
1033 (STp->buffer)->b_data[2], (STp->buffer)->b_data[3]));
1034
1035 if ((STp->buffer)->b_data[3] >= 8) {
1036 STp->drv_buffer = ((STp->buffer)->b_data[2] >> 4) & 7;
1037 STp->density = (STp->buffer)->b_data[4];
1038 STp->block_size = (STp->buffer)->b_data[9] * 65536 +
1039 (STp->buffer)->b_data[10] * 256 + (STp->buffer)->b_data[11];
1040 DEBC(printk(ST_DEB_MSG
1041 "%s: Density %x, tape length: %x, drv buffer: %d\n",
1042 name, STp->density, (STp->buffer)->b_data[5] * 65536 +
1043 (STp->buffer)->b_data[6] * 256 + (STp->buffer)->b_data[7],
1044 STp->drv_buffer));
1045 }
1046 STp->drv_write_prot = ((STp->buffer)->b_data[2] & 0x80) != 0;
1047 }
8b05b773 1048 st_release_request(SRpnt);
1da177e4
LT		 1049 SRpnt = NULL;
1050 STp->inited = 1;
1051
1052 if (STp->block_size > 0)
1053 (STp->buffer)->buffer_blocks =
1054 (STp->buffer)->buffer_size / STp->block_size;
1055 else
1056 (STp->buffer)->buffer_blocks = 1;
1057 (STp->buffer)->buffer_bytes = (STp->buffer)->read_pointer = 0;
1058
1059 DEBC(printk(ST_DEB_MSG
1060 "%s: Block size: %d, buffer size: %d (%d blocks).\n", name,
1061 STp->block_size, (STp->buffer)->buffer_size,
1062 (STp->buffer)->buffer_blocks));
1063
1064 if (STp->drv_write_prot) {
1065 STp->write_prot = 1;
1066
1067 DEBC(printk(ST_DEB_MSG "%s: Write protected\n", name));
1068
1069 if (do_wait &&
1070 ((st_flags & O_ACCMODE) == O_WRONLY ||
1071 (st_flags & O_ACCMODE) == O_RDWR)) {
1072 retval = (-EROFS);
1073 goto err_out;
1074 }
1075 }
1076
1077 if (STp->can_partitions && STp->nbr_partitions < 1) {
1078 /* This code is reached when the device is opened for the first time
1079 after the driver has been initialized with tape in the drive and the
1080 partition support has been enabled. */
1081 DEBC(printk(ST_DEB_MSG
1082 "%s: Updating partition number in status.\n", name));
1083 if ((STp->partition = find_partition(STp)) < 0) {
1084 retval = STp->partition;
1085 goto err_out;
1086 }
1087 STp->new_partition = STp->partition;
1088 STp->nbr_partitions = 1; /* This guess will be updated when necessary */
1089 }
1090
1091 if (new_session) { /* Change the drive parameters for the new mode */
1092 STp->density_changed = STp->blksize_changed = 0;
1093 STp->compression_changed = 0;
1094 if (!(STm->defaults_for_writes) &&
1095 (retval = set_mode_densblk(STp, STm)) < 0)
1096 goto err_out;
1097
1098 if (STp->default_drvbuffer != 0xff) {
1099 if (st_int_ioctl(STp, MTSETDRVBUFFER, STp->default_drvbuffer))
1100 printk(KERN_WARNING
1101 "%s: Can't set default drive buffering to %d.\n",
1102 name, STp->default_drvbuffer);
1103 }
1104 }
1105
1106 return CHKRES_READY;
1107
1108 err_out:
1109 return retval;
1110}
1111
1112
1113\f/* Open the device. Needs to be called with BKL only because of incrementing the SCSI host
1114 module count. */
1115static int st_open(struct inode *inode, struct file *filp)
1116{
1117 int i, retval = (-EIO);
1118 struct scsi_tape *STp;
1119 struct st_partstat *STps;
1120 int dev = TAPE_NR(inode);
1121 char *name;
1122
1123 /*
1124 * We really want to do nonseekable_open(inode, filp); here, but some
1125 * versions of tar incorrectly call lseek on tapes and bail out if that
1126 * fails. So we disallow pread() and pwrite(), but permit lseeks.
1127 */
1128 filp->f_mode &= ~(FMODE_PREAD | FMODE_PWRITE);
1129
f03a5670
KM		 1130 if (!(STp = scsi_tape_get(dev)))
1131 return -ENXIO;
1132
1da177e4 1133 write_lock(&st_dev_arr_lock);
1da177e4
LT		 1134 filp->private_data = STp;
1135 name = tape_name(STp);
1136
1137 if (STp->in_use) {
1138 write_unlock(&st_dev_arr_lock);
f03a5670 1139 scsi_tape_put(STp);
1da177e4
LT		 1140 DEB( printk(ST_DEB_MSG "%s: Device already in use.\n", name); )
1141 return (-EBUSY);
1142 }
1143
1da177e4
LT		 1144 STp->in_use = 1;
1145 write_unlock(&st_dev_arr_lock);
1146 STp->rew_at_close = STp->autorew_dev = (iminor(inode) & 0x80) == 0;
1147
1148 if (!scsi_block_when_processing_errors(STp->device)) {
1149 retval = (-ENXIO);
1150 goto err_out;
1151 }
1152
1153 /* See that we have at least a one page buffer available */
1154 if (!enlarge_buffer(STp->buffer, PAGE_SIZE, STp->restr_dma)) {
1155 printk(KERN_WARNING "%s: Can't allocate one page tape buffer.\n",
1156 name);
1157 retval = (-EOVERFLOW);
1158 goto err_out;
1159 }
1160
1161 (STp->buffer)->writing = 0;
1162 (STp->buffer)->syscall_result = 0;
1163
1164 STp->write_prot = ((filp->f_flags & O_ACCMODE) == O_RDONLY);
1165
1166 STp->dirty = 0;
1167 for (i = 0; i < ST_NBR_PARTITIONS; i++) {
1168 STps = &(STp->ps[i]);
1169 STps->rw = ST_IDLE;
1170 }
1171 STp->recover_count = 0;
1172 DEB( STp->nbr_waits = STp->nbr_finished = 0;
1173 STp->nbr_requests = STp->nbr_dio = STp->nbr_pages = STp->nbr_combinable = 0; )
1174
1175 retval = check_tape(STp, filp);
1176 if (retval < 0)
1177 goto err_out;
1178 if ((filp->f_flags & O_NONBLOCK) == 0 &&
1179 retval != CHKRES_READY) {
413f7327
KM		 1180 if (STp->ready == NO_TAPE)
1181 retval = (-ENOMEDIUM);
1182 else
1183 retval = (-EIO);
1da177e4
LT		 1184 goto err_out;
1185 }
1186 return 0;
1187
1188 err_out:
1189 normalize_buffer(STp->buffer);
1190 STp->in_use = 0;
f03a5670 1191 scsi_tape_put(STp);
1da177e4
LT		 1192 return retval;
1193
1194}
1195\f
1196
1197/* Flush the tape buffer before close */
75e1fcc0 1198static int st_flush(struct file *filp, fl_owner_t id)
1da177e4
LT		 1199{
1200 int result = 0, result2;
1201 unsigned char cmd[MAX_COMMAND_SIZE];
8b05b773 1202 struct st_request *SRpnt;
1da177e4
LT		 1203 struct scsi_tape *STp = filp->private_data;
1204 struct st_modedef *STm = &(STp->modes[STp->current_mode]);
1205 struct st_partstat *STps = &(STp->ps[STp->partition]);
1206 char *name = tape_name(STp);
1207
1208 if (file_count(filp) > 1)
1209 return 0;
1210
1211 if (STps->rw == ST_WRITING && !STp->pos_unknown) {
1212 result = flush_write_buffer(STp);
1213 if (result != 0 && result != (-ENOSPC))
1214 goto out;
1215 }
1216
1217 if (STp->can_partitions &&
1218 (result2 = switch_partition(STp)) < 0) {
1219 DEBC(printk(ST_DEB_MSG
1220 "%s: switch_partition at close failed.\n", name));
1221 if (result == 0)
1222 result = result2;
1223 goto out;
1224 }
1225
1226 DEBC( if (STp->nbr_requests)
42252854 1227 printk(KERN_DEBUG "%s: Number of r/w requests %d, dio used in %d, pages %d (%d).\n",
1da177e4
LT		 1228 name, STp->nbr_requests, STp->nbr_dio, STp->nbr_pages, STp->nbr_combinable));
1229
1230 if (STps->rw == ST_WRITING && !STp->pos_unknown) {
1231 struct st_cmdstatus *cmdstatp = &STp->buffer->cmdstat;
1232
1233 DEBC(printk(ST_DEB_MSG "%s: Async write waits %d, finished %d.\n",
1234 name, STp->nbr_waits, STp->nbr_finished);
1235 )
1236
1237 memset(cmd, 0, MAX_COMMAND_SIZE);
1238 cmd[0] = WRITE_FILEMARKS;
1239 cmd[4] = 1 + STp->two_fm;
1240
1241 SRpnt = st_do_scsi(NULL, STp, cmd, 0, DMA_NONE,
1242 STp->device->timeout, MAX_WRITE_RETRIES, 1);
1243 if (!SRpnt) {
1244 result = (STp->buffer)->syscall_result;
1245 goto out;
1246 }
1247
1248 if (STp->buffer->syscall_result == 0 ||
1249 (cmdstatp->have_sense && !cmdstatp->deferred &&
1250 (cmdstatp->flags & SENSE_EOM) &&
1251 (cmdstatp->sense_hdr.sense_key == NO_SENSE ||
1252 cmdstatp->sense_hdr.sense_key == RECOVERED_ERROR) &&
1253 (!cmdstatp->remainder_valid || cmdstatp->uremainder64 == 0))) {
1254 /* Write successful at EOM */
8b05b773 1255 st_release_request(SRpnt);
1da177e4
LT		 1256 SRpnt = NULL;
1257 if (STps->drv_file >= 0)
1258 STps->drv_file++;
1259 STps->drv_block = 0;
1260 if (STp->two_fm)
1261 cross_eof(STp, 0);
1262 STps->eof = ST_FM;
1263 }
1264 else { /* Write error */
8b05b773 1265 st_release_request(SRpnt);
1da177e4
LT		 1266 SRpnt = NULL;
1267 printk(KERN_ERR "%s: Error on write filemark.\n", name);
1268 if (result == 0)
1269 result = (-EIO);
1270 }
1271
1272 DEBC(printk(ST_DEB_MSG "%s: Buffer flushed, %d EOF(s) written\n",
1273 name, cmd[4]));
1274 } else if (!STp->rew_at_close) {
1275 STps = &(STp->ps[STp->partition]);
1276 if (!STm->sysv || STps->rw != ST_READING) {
1277 if (STp->can_bsr)
1278 result = flush_buffer(STp, 0);
1279 else if (STps->eof == ST_FM_HIT) {
1280 result = cross_eof(STp, 0);
1281 if (result) {
1282 if (STps->drv_file >= 0)
1283 STps->drv_file++;
1284 STps->drv_block = 0;
1285 STps->eof = ST_FM;
1286 } else
1287 STps->eof = ST_NOEOF;
1288 }
1289 } else if ((STps->eof == ST_NOEOF &&
1290 !(result = cross_eof(STp, 1))) ||
1291 STps->eof == ST_FM_HIT) {
1292 if (STps->drv_file >= 0)
1293 STps->drv_file++;
1294 STps->drv_block = 0;
1295 STps->eof = ST_FM;
1296 }
1297 }
1298
1299 out:
1300 if (STp->rew_at_close) {
1301 result2 = st_int_ioctl(STp, MTREW, 1);
1302 if (result == 0)
1303 result = result2;
1304 }
1305 return result;
1306}
1307
1308
1309/* Close the device and release it. BKL is not needed: this is the only thread
1310 accessing this tape. */
1311static int st_release(struct inode *inode, struct file *filp)
1312{
1313 int result = 0;
1314 struct scsi_tape *STp = filp->private_data;
1315
1316 if (STp->door_locked == ST_LOCKED_AUTO)
1317 do_door_lock(STp, 0);
1318
1319 normalize_buffer(STp->buffer);
1320 write_lock(&st_dev_arr_lock);
1321 STp->in_use = 0;
1322 write_unlock(&st_dev_arr_lock);
f03a5670 1323 scsi_tape_put(STp);
1da177e4
LT		 1324
1325 return result;
1326}
1327\f
1328/* The checks common to both reading and writing */
1329static ssize_t rw_checks(struct scsi_tape *STp, struct file *filp, size_t count)
1330{
1331 ssize_t retval = 0;
1332
1333 /*
1334 * If we are in the middle of error recovery, don't let anyone
1335 * else try and use this device. Also, if error recovery fails, it
1336 * may try and take the device offline, in which case all further
1337 * access to the device is prohibited.
1338 */
1339 if (!scsi_block_when_processing_errors(STp->device)) {
1340 retval = (-ENXIO);
1341 goto out;
1342 }
1343
1344 if (STp->ready != ST_READY) {
1345 if (STp->ready == ST_NO_TAPE)
1346 retval = (-ENOMEDIUM);
1347 else
1348 retval = (-EIO);
1349 goto out;
1350 }
1351
1352 if (! STp->modes[STp->current_mode].defined) {
1353 retval = (-ENXIO);
1354 goto out;
1355 }
1356
1357
1358 /*
1359 * If there was a bus reset, block further access
1360 * to this device.
1361 */
1362 if (STp->pos_unknown) {
1363 retval = (-EIO);
1364 goto out;
1365 }
1366
1367 if (count == 0)
1368 goto out;
1369
1370 DEB(
1371 if (!STp->in_use) {
1372 printk(ST_DEB_MSG "%s: Incorrect device.\n", tape_name(STp));
1373 retval = (-EIO);
1374 goto out;
1375 } ) /* end DEB */
1376
1377 if (STp->can_partitions &&
1378 (retval = switch_partition(STp)) < 0)
1379 goto out;
1380
1381 if (STp->block_size == 0 && STp->max_block > 0 &&
1382 (count < STp->min_block || count > STp->max_block)) {
1383 retval = (-EINVAL);
1384 goto out;
1385 }
1386
1387 if (STp->do_auto_lock && STp->door_locked == ST_UNLOCKED &&
1388 !do_door_lock(STp, 1))
1389 STp->door_locked = ST_LOCKED_AUTO;
1390
1391 out:
1392 return retval;
1393}
1394
1395
1396static int setup_buffering(struct scsi_tape *STp, const char __user *buf,
1397 size_t count, int is_read)
1398{
1399 int i, bufsize, retval = 0;
1400 struct st_buffer *STbp = STp->buffer;
1401
1402 if (is_read)
1403 i = STp->try_dio && try_rdio;
1404 else
1405 i = STp->try_dio && try_wdio;
8b05b773 1406
1da177e4
LT		 1407 if (i && ((unsigned long)buf & queue_dma_alignment(
1408 STp->device->request_queue)) == 0) {
8b05b773
MC		 1409 i = sgl_map_user_pages(&(STbp->sg[0]), STbp->use_sg,
1410 (unsigned long)buf, count, (is_read ? READ : WRITE));
1da177e4
LT		 1411 if (i > 0) {
1412 STbp->do_dio = i;
1413 STbp->buffer_bytes = 0; /* can be used as transfer counter */
1414 }
1415 else
1416 STbp->do_dio = 0; /* fall back to buffering with any error */
1417 STbp->sg_segs = STbp->do_dio;
1418 STbp->frp_sg_current = 0;
1419 DEB(
1420 if (STbp->do_dio) {
1421 STp->nbr_dio++;
1422 STp->nbr_pages += STbp->do_dio;
1423 for (i=1; i < STbp->do_dio; i++)
1424 if (page_to_pfn(STbp->sg[i].page) == page_to_pfn(STbp->sg[i-1].page) + 1)
1425 STp->nbr_combinable++;
1426 }
1427 )
1428 } else
1429 STbp->do_dio = 0;
1430 DEB( STp->nbr_requests++; )
1431
1432 if (!STbp->do_dio) {
1433 if (STp->block_size)
1434 bufsize = STp->block_size > st_fixed_buffer_size ?
1435 STp->block_size : st_fixed_buffer_size;
1436 else
1437 bufsize = count;
1438 if (bufsize > STbp->buffer_size &&
1439 !enlarge_buffer(STbp, bufsize, STp->restr_dma)) {
1440 printk(KERN_WARNING "%s: Can't allocate %d byte tape buffer.\n",
1441 tape_name(STp), bufsize);
1442 retval = (-EOVERFLOW);
1443 goto out;
1444 }
1445 if (STp->block_size)
1446 STbp->buffer_blocks = bufsize / STp->block_size;
1447 }
1448
1449 out:
1450 return retval;
1451}
1452
1453
1454/* Can be called more than once after each setup_buffer() */
787926b1 1455static void release_buffering(struct scsi_tape *STp, int is_read)
1da177e4
LT		 1456{
1457 struct st_buffer *STbp;
1458
1459 STbp = STp->buffer;
1460 if (STbp->do_dio) {
787926b1 1461 sgl_unmap_user_pages(&(STbp->sg[0]), STbp->do_dio, is_read);
1da177e4 1462 STbp->do_dio = 0;
787926b1 1463 STbp->sg_segs = 0;
1da177e4
LT		 1464 }
1465}
1466
1467
1468/* Write command */
1469static ssize_t
1470st_write(struct file *filp, const char __user *buf, size_t count, loff_t * ppos)
1471{
1472 ssize_t total;
1473 ssize_t i, do_count, blks, transfer;
1474 ssize_t retval;
1475 int undone, retry_eot = 0, scode;
1476 int async_write;
1477 unsigned char cmd[MAX_COMMAND_SIZE];
1478 const char __user *b_point;
8b05b773 1479 struct st_request *SRpnt = NULL;
1da177e4
LT		 1480 struct scsi_tape *STp = filp->private_data;
1481 struct st_modedef *STm;
1482 struct st_partstat *STps;
1483 struct st_buffer *STbp;
1484 char *name = tape_name(STp);
1485
1486 if (down_interruptible(&STp->lock))
1487 return -ERESTARTSYS;
1488
1489 retval = rw_checks(STp, filp, count);
1490 if (retval || count == 0)
1491 goto out;
1492
1493 /* Write must be integral number of blocks */
1494 if (STp->block_size != 0 && (count % STp->block_size) != 0) {
1495 printk(KERN_WARNING "%s: Write not multiple of tape block size.\n",
1496 name);
1497 retval = (-EINVAL);
1498 goto out;
1499 }
1500
1501 STm = &(STp->modes[STp->current_mode]);
1502 STps = &(STp->ps[STp->partition]);
1503
1504 if (STp->write_prot) {
1505 retval = (-EACCES);
1506 goto out;
1507 }
1508
1509
1510 if (STps->rw == ST_READING) {
1511 retval = flush_buffer(STp, 0);
1512 if (retval)
1513 goto out;
1514 STps->rw = ST_WRITING;
1515 } else if (STps->rw != ST_WRITING &&
1516 STps->drv_file == 0 && STps->drv_block == 0) {
1517 if ((retval = set_mode_densblk(STp, STm)) < 0)
1518 goto out;
1519 if (STm->default_compression != ST_DONT_TOUCH &&
1520 !(STp->compression_changed)) {
1521 if (st_compression(STp, (STm->default_compression == ST_YES))) {
1522 printk(KERN_WARNING "%s: Can't set default compression.\n",
1523 name);
1524 if (modes_defined) {
1525 retval = (-EINVAL);
1526 goto out;
1527 }
1528 }
1529 }
1530 }
1531
1532 STbp = STp->buffer;
1533 i = write_behind_check(STp);
1534 if (i) {
1535 if (i == -ENOSPC)
1536 STps->eof = ST_EOM_OK;
1537 else
1538 STps->eof = ST_EOM_ERROR;
1539 }
1540
1541 if (STps->eof == ST_EOM_OK) {
1542 STps->eof = ST_EOD_1; /* allow next write */
1543 retval = (-ENOSPC);
1544 goto out;
1545 }
1546 else if (STps->eof == ST_EOM_ERROR) {
1547 retval = (-EIO);
1548 goto out;
1549 }
1550
1551 /* Check the buffer readability in cases where copy_user might catch
1552 the problems after some tape movement. */
1553 if (STp->block_size != 0 &&
1554 !STbp->do_dio &&
1555 (copy_from_user(&i, buf, 1) != 0 ||
1556 copy_from_user(&i, buf + count - 1, 1) != 0)) {
1557 retval = (-EFAULT);
1558 goto out;
1559 }
1560
1561 retval = setup_buffering(STp, buf, count, 0);
1562 if (retval)
1563 goto out;
1564
1565 total = count;
1566
1567 memset(cmd, 0, MAX_COMMAND_SIZE);
1568 cmd[0] = WRITE_6;
1569 cmd[1] = (STp->block_size != 0);
1570
1571 STps->rw = ST_WRITING;
1572
1573 b_point = buf;
1574 while (count > 0 && !retry_eot) {
1575
1576 if (STbp->do_dio) {
1577 do_count = count;
1578 }
1579 else {
1580 if (STp->block_size == 0)
1581 do_count = count;
1582 else {
1583 do_count = STbp->buffer_blocks * STp->block_size -
1584 STbp->buffer_bytes;
1585 if (do_count > count)
1586 do_count = count;
1587 }
1588
1589 i = append_to_buffer(b_point, STbp, do_count);
1590 if (i) {
1591 retval = i;
1592 goto out;
1593 }
1594 }
1595 count -= do_count;
1596 b_point += do_count;
1597
1598 async_write = STp->block_size == 0 && !STbp->do_dio &&
1599 STm->do_async_writes && STps->eof < ST_EOM_OK;
1600
1601 if (STp->block_size != 0 && STm->do_buffer_writes &&
1602 !(STp->try_dio && try_wdio) && STps->eof < ST_EOM_OK &&
1603 STbp->buffer_bytes < STbp->buffer_size) {
1604 STp->dirty = 1;
1605 /* Don't write a buffer that is not full enough. */
1606 if (!async_write && count == 0)
1607 break;
1608 }
1609
1610 retry_write:
1611 if (STp->block_size == 0)
1612 blks = transfer = do_count;
1613 else {
1614 if (!STbp->do_dio)
1615 blks = STbp->buffer_bytes;
1616 else
1617 blks = do_count;
1618 blks /= STp->block_size;
1619 transfer = blks * STp->block_size;
1620 }
1621 cmd[2] = blks >> 16;
1622 cmd[3] = blks >> 8;
1623 cmd[4] = blks;
1624
1625 SRpnt = st_do_scsi(SRpnt, STp, cmd, transfer, DMA_TO_DEVICE,
1626 STp->device->timeout, MAX_WRITE_RETRIES, !async_write);
1627 if (!SRpnt) {
1628 retval = STbp->syscall_result;
1629 goto out;
1630 }
8b05b773 1631 if (async_write && !STbp->syscall_result) {
1da177e4
LT		 1632 STbp->writing = transfer;
1633 STp->dirty = !(STbp->writing ==
1634 STbp->buffer_bytes);
1635 SRpnt = NULL; /* Prevent releasing this request! */
1636 DEB( STp->write_pending = 1; )
1637 break;
1638 }
1639
1640 if (STbp->syscall_result != 0) {
1641 struct st_cmdstatus *cmdstatp = &STp->buffer->cmdstat;
1642
1643 DEBC(printk(ST_DEB_MSG "%s: Error on write:\n", name));
1644 if (cmdstatp->have_sense && (cmdstatp->flags & SENSE_EOM)) {
1645 scode = cmdstatp->sense_hdr.sense_key;
1646 if (cmdstatp->remainder_valid)
1647 undone = (int)cmdstatp->uremainder64;
1648 else if (STp->block_size == 0 &&
1649 scode == VOLUME_OVERFLOW)
1650 undone = transfer;
1651 else
1652 undone = 0;
1653 if (STp->block_size != 0)
1654 undone *= STp->block_size;
1655 if (undone <= do_count) {
1656 /* Only data from this write is not written */
1657 count += undone;
1658 do_count -= undone;
1659 if (STp->block_size)
1660 blks = (transfer - undone) / STp->block_size;
1661 STps->eof = ST_EOM_OK;
1662 /* Continue in fixed block mode if all written
1663 in this request but still something left to write
1664 (retval left to zero)
1665 */
1666 if (STp->block_size == 0 ||
1667 undone > 0 || count == 0)
1668 retval = (-ENOSPC); /* EOM within current request */
1669 DEBC(printk(ST_DEB_MSG
1670 "%s: EOM with %d bytes unwritten.\n",
1671 name, (int)count));
1672 } else {
1673 /* EOT within data buffered earlier (possible only
1674 in fixed block mode without direct i/o) */
1675 if (!retry_eot && !cmdstatp->deferred &&
1676 (scode == NO_SENSE || scode == RECOVERED_ERROR)) {
1677 move_buffer_data(STp->buffer, transfer - undone);
1678 retry_eot = 1;
1679 if (STps->drv_block >= 0) {
1680 STps->drv_block += (transfer - undone) /
1681 STp->block_size;
1682 }
1683 STps->eof = ST_EOM_OK;
1684 DEBC(printk(ST_DEB_MSG
1685 "%s: Retry write of %d bytes at EOM.\n",
1686 name, STp->buffer->buffer_bytes));
1687 goto retry_write;
1688 }
1689 else {
1690 /* Either error within data buffered by driver or
1691 failed retry */
1692 count -= do_count;
1693 blks = do_count = 0;
1694 STps->eof = ST_EOM_ERROR;
1695 STps->drv_block = (-1); /* Too cautious? */
1696 retval = (-EIO); /* EOM for old data */
1697 DEBC(printk(ST_DEB_MSG
1698 "%s: EOM with lost data.\n",
1699 name));
1700 }
1701 }
1702 } else {
1703 count += do_count;
1704 STps->drv_block = (-1); /* Too cautious? */
8b05b773 1705 retval = STbp->syscall_result;
1da177e4
LT		 1706 }
1707
1708 }
1709
1710 if (STps->drv_block >= 0) {
1711 if (STp->block_size == 0)
1712 STps->drv_block += (do_count > 0);
1713 else
1714 STps->drv_block += blks;
1715 }
1716
1717 STbp->buffer_bytes = 0;
1718 STp->dirty = 0;
1719
1720 if (retval || retry_eot) {
1721 if (count < total)
1722 retval = total - count;
1723 goto out;
1724 }
1725 }
1726
1727 if (STps->eof == ST_EOD_1)
1728 STps->eof = ST_EOM_OK;
1729 else if (STps->eof != ST_EOM_OK)
1730 STps->eof = ST_NOEOF;
1731 retval = total - count;
1732
1733 out:
1734 if (SRpnt != NULL)
8b05b773 1735 st_release_request(SRpnt);
787926b1 1736 release_buffering(STp, 0);
1da177e4
LT		 1737 up(&STp->lock);
1738
1739 return retval;
1740}
1741\f
1742/* Read data from the tape. Returns zero in the normal case, one if the
1743 eof status has changed, and the negative error code in case of a
1744 fatal error. Otherwise updates the buffer and the eof state.
1745
1746 Does release user buffer mapping if it is set.
1747*/
1748static long read_tape(struct scsi_tape *STp, long count,
8b05b773 1749 struct st_request ** aSRpnt)
1da177e4
LT		 1750{
1751 int transfer, blks, bytes;
1752 unsigned char cmd[MAX_COMMAND_SIZE];
8b05b773 1753 struct st_request *SRpnt;
1da177e4
LT		 1754 struct st_modedef *STm;
1755 struct st_partstat *STps;
1756 struct st_buffer *STbp;
1757 int retval = 0;
1758 char *name = tape_name(STp);
1759
1760 if (count == 0)
1761 return 0;
1762
1763 STm = &(STp->modes[STp->current_mode]);
1764 STps = &(STp->ps[STp->partition]);
1765 if (STps->eof == ST_FM_HIT)
1766 return 1;
1767 STbp = STp->buffer;
1768
1769 if (STp->block_size == 0)
1770 blks = bytes = count;
1771 else {
1772 if (!(STp->try_dio && try_rdio) && STm->do_read_ahead) {
1773 blks = (STp->buffer)->buffer_blocks;
1774 bytes = blks * STp->block_size;
1775 } else {
1776 bytes = count;
1777 if (!STbp->do_dio && bytes > (STp->buffer)->buffer_size)
1778 bytes = (STp->buffer)->buffer_size;
1779 blks = bytes / STp->block_size;
1780 bytes = blks * STp->block_size;
1781 }
1782 }
1783
1784 memset(cmd, 0, MAX_COMMAND_SIZE);
1785 cmd[0] = READ_6;
1786 cmd[1] = (STp->block_size != 0);
1787 cmd[2] = blks >> 16;
1788 cmd[3] = blks >> 8;
1789 cmd[4] = blks;
1790
1791 SRpnt = *aSRpnt;
1792 SRpnt = st_do_scsi(SRpnt, STp, cmd, bytes, DMA_FROM_DEVICE,
1793 STp->device->timeout, MAX_RETRIES, 1);
787926b1 1794 release_buffering(STp, 1);
1da177e4
LT		 1795 *aSRpnt = SRpnt;
1796 if (!SRpnt)
1797 return STbp->syscall_result;
1798
1799 STbp->read_pointer = 0;
1800 STps->at_sm = 0;
1801
1802 /* Something to check */
1803 if (STbp->syscall_result) {
1804 struct st_cmdstatus *cmdstatp = &STp->buffer->cmdstat;
1805
1806 retval = 1;
1807 DEBC(printk(ST_DEB_MSG "%s: Sense: %2x %2x %2x %2x %2x %2x %2x %2x\n",
1808 name,
8b05b773
MC		 1809 SRpnt->sense[0], SRpnt->sense[1],
1810 SRpnt->sense[2], SRpnt->sense[3],
1811 SRpnt->sense[4], SRpnt->sense[5],
1812 SRpnt->sense[6], SRpnt->sense[7]));
1da177e4
LT		 1813 if (cmdstatp->have_sense) {
1814
1815 if (cmdstatp->sense_hdr.sense_key == BLANK_CHECK)
1816 cmdstatp->flags &= 0xcf; /* No need for EOM in this case */
1817
1818 if (cmdstatp->flags != 0) { /* EOF, EOM, or ILI */
1819 /* Compute the residual count */
1820 if (cmdstatp->remainder_valid)
1821 transfer = (int)cmdstatp->uremainder64;
1822 else
1823 transfer = 0;
1824 if (STp->block_size == 0 &&
1825 cmdstatp->sense_hdr.sense_key == MEDIUM_ERROR)
1826 transfer = bytes;
1827
1828 if (cmdstatp->flags & SENSE_ILI) { /* ILI */
1829 if (STp->block_size == 0) {
1830 if (transfer <= 0) {
1831 if (transfer < 0)
1832 printk(KERN_NOTICE
1833 "%s: Failed to read %d byte block with %d byte transfer.\n",
1834 name, bytes - transfer, bytes);
1835 if (STps->drv_block >= 0)
1836 STps->drv_block += 1;
1837 STbp->buffer_bytes = 0;
1838 return (-ENOMEM);
1839 }
1840 STbp->buffer_bytes = bytes - transfer;
1841 } else {
8b05b773 1842 st_release_request(SRpnt);
1da177e4
LT		 1843 SRpnt = *aSRpnt = NULL;
1844 if (transfer == blks) { /* We did not get anything, error */
1845 printk(KERN_NOTICE "%s: Incorrect block size.\n", name);
1846 if (STps->drv_block >= 0)
1847 STps->drv_block += blks - transfer + 1;
1848 st_int_ioctl(STp, MTBSR, 1);
1849 return (-EIO);
1850 }
1851 /* We have some data, deliver it */
1852 STbp->buffer_bytes = (blks - transfer) *
1853 STp->block_size;
1854 DEBC(printk(ST_DEB_MSG
1855 "%s: ILI but enough data received %ld %d.\n",
1856 name, count, STbp->buffer_bytes));
1857 if (STps->drv_block >= 0)
1858 STps->drv_block += 1;
1859 if (st_int_ioctl(STp, MTBSR, 1))
1860 return (-EIO);
1861 }
1862 } else if (cmdstatp->flags & SENSE_FMK) { /* FM overrides EOM */
1863 if (STps->eof != ST_FM_HIT)
1864 STps->eof = ST_FM_HIT;
1865 else
1866 STps->eof = ST_EOD_2;
1867 if (STp->block_size == 0)
1868 STbp->buffer_bytes = 0;
1869 else
1870 STbp->buffer_bytes =
1871 bytes - transfer * STp->block_size;
1872 DEBC(printk(ST_DEB_MSG
1873 "%s: EOF detected (%d bytes read).\n",
1874 name, STbp->buffer_bytes));
1875 } else if (cmdstatp->flags & SENSE_EOM) {
1876 if (STps->eof == ST_FM)
1877 STps->eof = ST_EOD_1;
1878 else
1879 STps->eof = ST_EOM_OK;
1880 if (STp->block_size == 0)
1881 STbp->buffer_bytes = bytes - transfer;
1882 else
1883 STbp->buffer_bytes =
1884 bytes - transfer * STp->block_size;
1885
1886 DEBC(printk(ST_DEB_MSG "%s: EOM detected (%d bytes read).\n",
1887 name, STbp->buffer_bytes));
1888 }
1889 }
1890 /* end of EOF, EOM, ILI test */
1891 else { /* nonzero sense key */
1892 DEBC(printk(ST_DEB_MSG
1893 "%s: Tape error while reading.\n", name));
1894 STps->drv_block = (-1);
1895 if (STps->eof == ST_FM &&
1896 cmdstatp->sense_hdr.sense_key == BLANK_CHECK) {
1897 DEBC(printk(ST_DEB_MSG
1898 "%s: Zero returned for first BLANK CHECK after EOF.\n",
1899 name));
1900 STps->eof = ST_EOD_2; /* First BLANK_CHECK after FM */
1901 } else /* Some other extended sense code */
1902 retval = (-EIO);
1903 }
1904
1905 if (STbp->buffer_bytes < 0) /* Caused by bogus sense data */
1906 STbp->buffer_bytes = 0;
1907 }
1908 /* End of extended sense test */
1909 else { /* Non-extended sense */
1910 retval = STbp->syscall_result;
1911 }
1912
1913 }
1914 /* End of error handling */
1915 else /* Read successful */
1916 STbp->buffer_bytes = bytes;
1917
1918 if (STps->drv_block >= 0) {
1919 if (STp->block_size == 0)
1920 STps->drv_block++;
1921 else
1922 STps->drv_block += STbp->buffer_bytes / STp->block_size;
1923 }
1924 return retval;
1925}
1926\f
1927
1928/* Read command */
1929static ssize_t
1930st_read(struct file *filp, char __user *buf, size_t count, loff_t * ppos)
1931{
1932 ssize_t total;
1933 ssize_t retval = 0;
1934 ssize_t i, transfer;
1935 int special, do_dio = 0;
8b05b773 1936 struct st_request *SRpnt = NULL;
1da177e4
LT		 1937 struct scsi_tape *STp = filp->private_data;
1938 struct st_modedef *STm;
1939 struct st_partstat *STps;
1940 struct st_buffer *STbp = STp->buffer;
1941 DEB( char *name = tape_name(STp); )
1942
1943 if (down_interruptible(&STp->lock))
1944 return -ERESTARTSYS;
1945
1946 retval = rw_checks(STp, filp, count);
1947 if (retval || count == 0)
1948 goto out;
1949
1950 STm = &(STp->modes[STp->current_mode]);
1951 if (!(STm->do_read_ahead) && STp->block_size != 0 &&
1952 (count % STp->block_size) != 0) {
1953 retval = (-EINVAL); /* Read must be integral number of blocks */
1954 goto out;
1955 }
1956
1957 STps = &(STp->ps[STp->partition]);
1958 if (STps->rw == ST_WRITING) {
1959 retval = flush_buffer(STp, 0);
1960 if (retval)
1961 goto out;
1962 STps->rw = ST_READING;
1963 }
1964 DEB(
1965 if (debugging && STps->eof != ST_NOEOF)
1966 printk(ST_DEB_MSG "%s: EOF/EOM flag up (%d). Bytes %d\n", name,
1967 STps->eof, STbp->buffer_bytes);
1968 ) /* end DEB */
1969
1970 retval = setup_buffering(STp, buf, count, 1);
1971 if (retval)
1972 goto out;
1973 do_dio = STbp->do_dio;
1974
1975 if (STbp->buffer_bytes == 0 &&
1976 STps->eof >= ST_EOD_1) {
1977 if (STps->eof < ST_EOD) {
1978 STps->eof += 1;
1979 retval = 0;
1980 goto out;
1981 }
1982 retval = (-EIO); /* EOM or Blank Check */
1983 goto out;
1984 }
1985
1986 if (do_dio) {
1987 /* Check the buffer writability before any tape movement. Don't alter
1988 buffer data. */
1989 if (copy_from_user(&i, buf, 1) != 0 ||
1990 copy_to_user(buf, &i, 1) != 0 ||
1991 copy_from_user(&i, buf + count - 1, 1) != 0 ||
1992 copy_to_user(buf + count - 1, &i, 1) != 0) {
1993 retval = (-EFAULT);
1994 goto out;
1995 }
1996 }
1997
1998 STps->rw = ST_READING;
1999
2000
2001 /* Loop until enough data in buffer or a special condition found */
2002 for (total = 0, special = 0; total < count && !special;) {
2003
2004 /* Get new data if the buffer is empty */
2005 if (STbp->buffer_bytes == 0) {
2006 special = read_tape(STp, count - total, &SRpnt);
2007 if (special < 0) { /* No need to continue read */
2008 retval = special;
2009 goto out;
2010 }
2011 }
2012
2013 /* Move the data from driver buffer to user buffer */
2014 if (STbp->buffer_bytes > 0) {
2015 DEB(
2016 if (debugging && STps->eof != ST_NOEOF)
2017 printk(ST_DEB_MSG
2018 "%s: EOF up (%d). Left %d, needed %d.\n", name,
2019 STps->eof, STbp->buffer_bytes,
2020 (int)(count - total));
2021 ) /* end DEB */
2022 transfer = STbp->buffer_bytes < count - total ?
2023 STbp->buffer_bytes : count - total;
2024 if (!do_dio) {
2025 i = from_buffer(STbp, buf, transfer);
2026 if (i) {
2027 retval = i;
2028 goto out;
2029 }
2030 }
2031 buf += transfer;
2032 total += transfer;
2033 }
2034
2035 if (STp->block_size == 0)
2036 break; /* Read only one variable length block */
2037
2038 } /* for (total = 0, special = 0;
2039 total < count && !special; ) */
2040
2041 /* Change the eof state if no data from tape or buffer */
2042 if (total == 0) {
2043 if (STps->eof == ST_FM_HIT) {
2044 STps->eof = ST_FM;
2045 STps->drv_block = 0;
2046 if (STps->drv_file >= 0)
2047 STps->drv_file++;
2048 } else if (STps->eof == ST_EOD_1) {
2049 STps->eof = ST_EOD_2;
2050 STps->drv_block = 0;
2051 if (STps->drv_file >= 0)
2052 STps->drv_file++;
2053 } else if (STps->eof == ST_EOD_2)
2054 STps->eof = ST_EOD;
2055 } else if (STps->eof == ST_FM)
2056 STps->eof = ST_NOEOF;
2057 retval = total;
2058
2059 out:
2060 if (SRpnt != NULL) {
8b05b773 2061 st_release_request(SRpnt);
1da177e4
LT		 2062 SRpnt = NULL;
2063 }
2064 if (do_dio) {
787926b1 2065 release_buffering(STp, 1);
1da177e4
LT		 2066 STbp->buffer_bytes = 0;
2067 }
2068 up(&STp->lock);
2069
2070 return retval;
2071}
2072\f
2073
2074
2075DEB(
2076/* Set the driver options */
2077static void st_log_options(struct scsi_tape * STp, struct st_modedef * STm, char *name)
2078{
2079 if (debugging) {
2080 printk(KERN_INFO
2081 "%s: Mode %d options: buffer writes: %d, async writes: %d, read ahead: %d\n",
2082 name, STp->current_mode, STm->do_buffer_writes, STm->do_async_writes,
2083 STm->do_read_ahead);
2084 printk(KERN_INFO
2085 "%s: can bsr: %d, two FMs: %d, fast mteom: %d, auto lock: %d,\n",
2086 name, STp->can_bsr, STp->two_fm, STp->fast_mteom, STp->do_auto_lock);
2087 printk(KERN_INFO
2088 "%s: defs for wr: %d, no block limits: %d, partitions: %d, s2 log: %d\n",
2089 name, STm->defaults_for_writes, STp->omit_blklims, STp->can_partitions,
2090 STp->scsi2_logical);
2091 printk(KERN_INFO
2092 "%s: sysv: %d nowait: %d\n", name, STm->sysv, STp->immediate);
2093 printk(KERN_INFO "%s: debugging: %d\n",
2094 name, debugging);
2095 }
2096}
2097 )
2098
2099
2100static int st_set_options(struct scsi_tape *STp, long options)
2101{
2102 int value;
2103 long code;
2104 struct st_modedef *STm;
2105 char *name = tape_name(STp);
2106 struct cdev *cd0, *cd1;
2107
2108 STm = &(STp->modes[STp->current_mode]);
2109 if (!STm->defined) {
2110 cd0 = STm->cdevs[0]; cd1 = STm->cdevs[1];
2111 memcpy(STm, &(STp->modes[0]), sizeof(struct st_modedef));
2112 STm->cdevs[0] = cd0; STm->cdevs[1] = cd1;
2113 modes_defined = 1;
2114 DEBC(printk(ST_DEB_MSG
2115 "%s: Initialized mode %d definition from mode 0\n",
2116 name, STp->current_mode));
2117 }
2118
2119 code = options & MT_ST_OPTIONS;
2120 if (code == MT_ST_BOOLEANS) {
2121 STm->do_buffer_writes = (options & MT_ST_BUFFER_WRITES) != 0;
2122 STm->do_async_writes = (options & MT_ST_ASYNC_WRITES) != 0;
2123 STm->defaults_for_writes = (options & MT_ST_DEF_WRITES) != 0;
2124 STm->do_read_ahead = (options & MT_ST_READ_AHEAD) != 0;
2125 STp->two_fm = (options & MT_ST_TWO_FM) != 0;
2126 STp->fast_mteom = (options & MT_ST_FAST_MTEOM) != 0;
2127 STp->do_auto_lock = (options & MT_ST_AUTO_LOCK) != 0;
2128 STp->can_bsr = (options & MT_ST_CAN_BSR) != 0;
2129 STp->omit_blklims = (options & MT_ST_NO_BLKLIMS) != 0;
2130 if ((STp->device)->scsi_level >= SCSI_2)
2131 STp->can_partitions = (options & MT_ST_CAN_PARTITIONS) != 0;
2132 STp->scsi2_logical = (options & MT_ST_SCSI2LOGICAL) != 0;
2133 STp->immediate = (options & MT_ST_NOWAIT) != 0;
2134 STm->sysv = (options & MT_ST_SYSV) != 0;
2135 DEB( debugging = (options & MT_ST_DEBUGGING) != 0;
2136 st_log_options(STp, STm, name); )
2137 } else if (code == MT_ST_SETBOOLEANS || code == MT_ST_CLEARBOOLEANS) {
2138 value = (code == MT_ST_SETBOOLEANS);
2139 if ((options & MT_ST_BUFFER_WRITES) != 0)
2140 STm->do_buffer_writes = value;
2141 if ((options & MT_ST_ASYNC_WRITES) != 0)
2142 STm->do_async_writes = value;
2143 if ((options & MT_ST_DEF_WRITES) != 0)
2144 STm->defaults_for_writes = value;
2145 if ((options & MT_ST_READ_AHEAD) != 0)
2146 STm->do_read_ahead = value;
2147 if ((options & MT_ST_TWO_FM) != 0)
2148 STp->two_fm = value;
2149 if ((options & MT_ST_FAST_MTEOM) != 0)
2150 STp->fast_mteom = value;
2151 if ((options & MT_ST_AUTO_LOCK) != 0)
2152 STp->do_auto_lock = value;
2153 if ((options & MT_ST_CAN_BSR) != 0)
2154 STp->can_bsr = value;
2155 if ((options & MT_ST_NO_BLKLIMS) != 0)
2156 STp->omit_blklims = value;
2157 if ((STp->device)->scsi_level >= SCSI_2 &&
2158 (options & MT_ST_CAN_PARTITIONS) != 0)
2159 STp->can_partitions = value;
2160 if ((options & MT_ST_SCSI2LOGICAL) != 0)
2161 STp->scsi2_logical = value;
2162 if ((options & MT_ST_NOWAIT) != 0)
2163 STp->immediate = value;
2164 if ((options & MT_ST_SYSV) != 0)
2165 STm->sysv = value;
2166 DEB(
2167 if ((options & MT_ST_DEBUGGING) != 0)
2168 debugging = value;
2169 st_log_options(STp, STm, name); )
2170 } else if (code == MT_ST_WRITE_THRESHOLD) {
2171 /* Retained for compatibility */
2172 } else if (code == MT_ST_DEF_BLKSIZE) {
2173 value = (options & ~MT_ST_OPTIONS);
2174 if (value == ~MT_ST_OPTIONS) {
2175 STm->default_blksize = (-1);
2176 DEBC( printk(KERN_INFO "%s: Default block size disabled.\n", name));
2177 } else {
2178 STm->default_blksize = value;
2179 DEBC( printk(KERN_INFO "%s: Default block size set to %d bytes.\n",
2180 name, STm->default_blksize));
2181 if (STp->ready == ST_READY) {
2182 STp->blksize_changed = 0;
2183 set_mode_densblk(STp, STm);
2184 }
2185 }
2186 } else if (code == MT_ST_TIMEOUTS) {
2187 value = (options & ~MT_ST_OPTIONS);
2188 if ((value & MT_ST_SET_LONG_TIMEOUT) != 0) {
2189 STp->long_timeout = (value & ~MT_ST_SET_LONG_TIMEOUT) * HZ;
2190 DEBC( printk(KERN_INFO "%s: Long timeout set to %d seconds.\n", name,
2191 (value & ~MT_ST_SET_LONG_TIMEOUT)));
2192 } else {
2193 STp->device->timeout = value * HZ;
2194 DEBC( printk(KERN_INFO "%s: Normal timeout set to %d seconds.\n",
2195 name, value) );
2196 }
2197 } else if (code == MT_ST_SET_CLN) {
2198 value = (options & ~MT_ST_OPTIONS) & 0xff;
2199 if (value != 0 &&
2200 value < EXTENDED_SENSE_START && value >= SCSI_SENSE_BUFFERSIZE)
2201 return (-EINVAL);
2202 STp->cln_mode = value;
2203 STp->cln_sense_mask = (options >> 8) & 0xff;
2204 STp->cln_sense_value = (options >> 16) & 0xff;
2205 printk(KERN_INFO
2206 "%s: Cleaning request mode %d, mask %02x, value %02x\n",
2207 name, value, STp->cln_sense_mask, STp->cln_sense_value);
2208 } else if (code == MT_ST_DEF_OPTIONS) {
2209 code = (options & ~MT_ST_CLEAR_DEFAULT);
2210 value = (options & MT_ST_CLEAR_DEFAULT);
2211 if (code == MT_ST_DEF_DENSITY) {
2212 if (value == MT_ST_CLEAR_DEFAULT) {
2213 STm->default_density = (-1);
2214 DEBC( printk(KERN_INFO "%s: Density default disabled.\n",
2215 name));
2216 } else {
2217 STm->default_density = value & 0xff;
2218 DEBC( printk(KERN_INFO "%s: Density default set to %x\n",
2219 name, STm->default_density));
2220 if (STp->ready == ST_READY) {
2221 STp->density_changed = 0;
2222 set_mode_densblk(STp, STm);
2223 }
2224 }
2225 } else if (code == MT_ST_DEF_DRVBUFFER) {
2226 if (value == MT_ST_CLEAR_DEFAULT) {
2227 STp->default_drvbuffer = 0xff;
2228 DEBC( printk(KERN_INFO
2229 "%s: Drive buffer default disabled.\n", name));
2230 } else {
2231 STp->default_drvbuffer = value & 7;
2232 DEBC( printk(KERN_INFO
2233 "%s: Drive buffer default set to %x\n",
2234 name, STp->default_drvbuffer));
2235 if (STp->ready == ST_READY)
2236 st_int_ioctl(STp, MTSETDRVBUFFER, STp->default_drvbuffer);
2237 }
2238 } else if (code == MT_ST_DEF_COMPRESSION) {
2239 if (value == MT_ST_CLEAR_DEFAULT) {
2240 STm->default_compression = ST_DONT_TOUCH;
2241 DEBC( printk(KERN_INFO
2242 "%s: Compression default disabled.\n", name));
2243 } else {
2244 if ((value & 0xff00) != 0) {
2245 STp->c_algo = (value & 0xff00) >> 8;
2246 DEBC( printk(KERN_INFO "%s: Compression algorithm set to 0x%x.\n",
2247 name, STp->c_algo));
2248 }
2249 if ((value & 0xff) != 0xff) {
2250 STm->default_compression = (value & 1 ? ST_YES : ST_NO);
2251 DEBC( printk(KERN_INFO "%s: Compression default set to %x\n",
2252 name, (value & 1)));
2253 if (STp->ready == ST_READY) {
2254 STp->compression_changed = 0;
2255 st_compression(STp, (STm->default_compression == ST_YES));
2256 }
2257 }
2258 }
2259 }
2260 } else
2261 return (-EIO);
2262
2263 return 0;
2264}
2265\f
2266#define MODE_HEADER_LENGTH 4
2267
2268/* Mode header and page byte offsets */
2269#define MH_OFF_DATA_LENGTH 0
2270#define MH_OFF_MEDIUM_TYPE 1
2271#define MH_OFF_DEV_SPECIFIC 2
2272#define MH_OFF_BDESCS_LENGTH 3
2273#define MP_OFF_PAGE_NBR 0
2274#define MP_OFF_PAGE_LENGTH 1
2275
2276/* Mode header and page bit masks */
2277#define MH_BIT_WP 0x80
2278#define MP_MSK_PAGE_NBR 0x3f
2279
2280/* Don't return block descriptors */
2281#define MODE_SENSE_OMIT_BDESCS 0x08
2282
2283#define MODE_SELECT_PAGE_FORMAT 0x10
2284
2285/* Read a mode page into the tape buffer. The block descriptors are included
2286 if incl_block_descs is true. The page control is ored to the page number
2287 parameter, if necessary. */
2288static int read_mode_page(struct scsi_tape *STp, int page, int omit_block_descs)
2289{
2290 unsigned char cmd[MAX_COMMAND_SIZE];
8b05b773 2291 struct st_request *SRpnt = NULL;
1da177e4
LT		 2292
2293 memset(cmd, 0, MAX_COMMAND_SIZE);
2294 cmd[0] = MODE_SENSE;
2295 if (omit_block_descs)
2296 cmd[1] = MODE_SENSE_OMIT_BDESCS;
2297 cmd[2] = page;
2298 cmd[4] = 255;
2299
2300 SRpnt = st_do_scsi(SRpnt, STp, cmd, cmd[4], DMA_FROM_DEVICE,
2301 STp->device->timeout, 0, 1);
2302 if (SRpnt == NULL)
2303 return (STp->buffer)->syscall_result;
2304
8b05b773 2305 st_release_request(SRpnt);
1da177e4
LT		 2306
2307 return (STp->buffer)->syscall_result;
2308}
2309
2310
2311/* Send the mode page in the tape buffer to the drive. Assumes that the mode data
2312 in the buffer is correctly formatted. The long timeout is used if slow is non-zero. */
2313static int write_mode_page(struct scsi_tape *STp, int page, int slow)
2314{
2315 int pgo;
2316 unsigned char cmd[MAX_COMMAND_SIZE];
8b05b773 2317 struct st_request *SRpnt = NULL;
1da177e4
LT		 2318
2319 memset(cmd, 0, MAX_COMMAND_SIZE);
2320 cmd[0] = MODE_SELECT;
2321 cmd[1] = MODE_SELECT_PAGE_FORMAT;
2322 pgo = MODE_HEADER_LENGTH + (STp->buffer)->b_data[MH_OFF_BDESCS_LENGTH];
2323 cmd[4] = pgo + (STp->buffer)->b_data[pgo + MP_OFF_PAGE_LENGTH] + 2;
2324
2325 /* Clear reserved fields */
2326 (STp->buffer)->b_data[MH_OFF_DATA_LENGTH] = 0;
2327 (STp->buffer)->b_data[MH_OFF_MEDIUM_TYPE] = 0;
2328 (STp->buffer)->b_data[MH_OFF_DEV_SPECIFIC] &= ~MH_BIT_WP;
2329 (STp->buffer)->b_data[pgo + MP_OFF_PAGE_NBR] &= MP_MSK_PAGE_NBR;
2330
2331 SRpnt = st_do_scsi(SRpnt, STp, cmd, cmd[4], DMA_TO_DEVICE,
2332 (slow ? STp->long_timeout : STp->device->timeout), 0, 1);
2333 if (SRpnt == NULL)
2334 return (STp->buffer)->syscall_result;
2335
8b05b773 2336 st_release_request(SRpnt);
1da177e4
LT		 2337
2338 return (STp->buffer)->syscall_result;
2339}
2340
2341
2342#define COMPRESSION_PAGE 0x0f
2343#define COMPRESSION_PAGE_LENGTH 16
2344
2345#define CP_OFF_DCE_DCC 2
2346#define CP_OFF_C_ALGO 7
2347
2348#define DCE_MASK 0x80
2349#define DCC_MASK 0x40
2350#define RED_MASK 0x60
2351
2352
2353/* Control the compression with mode page 15. Algorithm not changed if zero.
2354
2355 The block descriptors are read and written because Sony SDT-7000 does not
2356 work without this (suggestion from Michael Schaefer <Michael.Schaefer@dlr.de>).
2357 Including block descriptors should not cause any harm to other drives. */
2358
2359static int st_compression(struct scsi_tape * STp, int state)
2360{
2361 int retval;
2362 int mpoffs; /* Offset to mode page start */
2363 unsigned char *b_data = (STp->buffer)->b_data;
2364 DEB( char *name = tape_name(STp); )
2365
2366 if (STp->ready != ST_READY)
2367 return (-EIO);
2368
2369 /* Read the current page contents */
2370 retval = read_mode_page(STp, COMPRESSION_PAGE, 0);
2371 if (retval) {
2372 DEBC(printk(ST_DEB_MSG "%s: Compression mode page not supported.\n",
2373 name));
2374 return (-EIO);
2375 }
2376
2377 mpoffs = MODE_HEADER_LENGTH + b_data[MH_OFF_BDESCS_LENGTH];
2378 DEBC(printk(ST_DEB_MSG "%s: Compression state is %d.\n", name,
2379 (b_data[mpoffs + CP_OFF_DCE_DCC] & DCE_MASK ? 1 : 0)));
2380
2381 /* Check if compression can be changed */
2382 if ((b_data[mpoffs + CP_OFF_DCE_DCC] & DCC_MASK) == 0) {
2383 DEBC(printk(ST_DEB_MSG "%s: Compression not supported.\n", name));
2384 return (-EIO);
2385 }
2386
2387 /* Do the change */
2388 if (state) {
2389 b_data[mpoffs + CP_OFF_DCE_DCC] |= DCE_MASK;
2390 if (STp->c_algo != 0)
2391 b_data[mpoffs + CP_OFF_C_ALGO] = STp->c_algo;
2392 }
2393 else {
2394 b_data[mpoffs + CP_OFF_DCE_DCC] &= ~DCE_MASK;
2395 if (STp->c_algo != 0)
2396 b_data[mpoffs + CP_OFF_C_ALGO] = 0; /* no compression */
2397 }
2398
2399 retval = write_mode_page(STp, COMPRESSION_PAGE, 0);
2400 if (retval) {
2401 DEBC(printk(ST_DEB_MSG "%s: Compression change failed.\n", name));
2402 return (-EIO);
2403 }
2404 DEBC(printk(ST_DEB_MSG "%s: Compression state changed to %d.\n",
2405 name, state));
2406
2407 STp->compression_changed = 1;
2408 return 0;
2409}
2410
2411
2412/* Process the load and unload commands (does unload if the load code is zero) */
2413static int do_load_unload(struct scsi_tape *STp, struct file *filp, int load_code)
2414{
2415 int retval = (-EIO), timeout;
2416 DEB( char *name = tape_name(STp); )
2417 unsigned char cmd[MAX_COMMAND_SIZE];
2418 struct st_partstat *STps;
8b05b773 2419 struct st_request *SRpnt;
1da177e4
LT		 2420
2421 if (STp->ready != ST_READY && !load_code) {
2422 if (STp->ready == ST_NO_TAPE)
2423 return (-ENOMEDIUM);
2424 else
2425 return (-EIO);
2426 }
2427
2428 memset(cmd, 0, MAX_COMMAND_SIZE);
2429 cmd[0] = START_STOP;
2430 if (load_code)
2431 cmd[4] |= 1;
2432 /*
2433 * If arg >= 1 && arg <= 6 Enhanced load/unload in HP C1553A
2434 */
2435 if (load_code >= 1 + MT_ST_HPLOADER_OFFSET
2436 && load_code <= 6 + MT_ST_HPLOADER_OFFSET) {
2437 DEBC(printk(ST_DEB_MSG "%s: Enhanced %sload slot %2d.\n",
2438 name, (cmd[4]) ? "" : "un",
2439 load_code - MT_ST_HPLOADER_OFFSET));
2440 cmd[3] = load_code - MT_ST_HPLOADER_OFFSET; /* MediaID field of C1553A */
2441 }
2442 if (STp->immediate) {
2443 cmd[1] = 1; /* Don't wait for completion */
2444 timeout = STp->device->timeout;
2445 }
2446 else
2447 timeout = STp->long_timeout;
2448
2449 DEBC(
2450 if (!load_code)
2451 printk(ST_DEB_MSG "%s: Unloading tape.\n", name);
2452 else
2453 printk(ST_DEB_MSG "%s: Loading tape.\n", name);
2454 );
2455
2456 SRpnt = st_do_scsi(NULL, STp, cmd, 0, DMA_NONE,
2457 timeout, MAX_RETRIES, 1);
2458 if (!SRpnt)
2459 return (STp->buffer)->syscall_result;
2460
2461 retval = (STp->buffer)->syscall_result;
8b05b773 2462 st_release_request(SRpnt);
1da177e4
LT		 2463
2464 if (!retval) { /* SCSI command successful */
2465
2466 if (!load_code) {
2467 STp->rew_at_close = 0;
2468 STp->ready = ST_NO_TAPE;
2469 }
2470 else {
2471 STp->rew_at_close = STp->autorew_dev;
2472 retval = check_tape(STp, filp);
2473 if (retval > 0)
2474 retval = 0;
2475 }
2476 }
2477 else {
2478 STps = &(STp->ps[STp->partition]);
2479 STps->drv_file = STps->drv_block = (-1);
2480 }
2481
2482 return retval;
2483}
2484\f
2485#if DEBUG
2486#define ST_DEB_FORWARD 0
2487#define ST_DEB_BACKWARD 1
2488static void deb_space_print(char *name, int direction, char *units, unsigned char *cmd)
2489{
2490 s32 sc;
2491
2492 sc = cmd[2] & 0x80 ? 0xff000000 : 0;
2493 sc |= (cmd[2] << 16) | (cmd[3] << 8) | cmd[4];
2494 if (direction)
2495 sc = -sc;
2496 printk(ST_DEB_MSG "%s: Spacing tape %s over %d %s.\n", name,
2497 direction ? "backward" : "forward", sc, units);
2498}
2499#endif
2500
2501
2502/* Internal ioctl function */
2503static int st_int_ioctl(struct scsi_tape *STp, unsigned int cmd_in, unsigned long arg)
2504{
2505 int timeout;
2506 long ltmp;
2507 int ioctl_result;
2508 int chg_eof = 1;
2509 unsigned char cmd[MAX_COMMAND_SIZE];
8b05b773 2510 struct st_request *SRpnt;
1da177e4
LT		 2511 struct st_partstat *STps;
2512 int fileno, blkno, at_sm, undone;
2513 int datalen = 0, direction = DMA_NONE;
2514 char *name = tape_name(STp);
2515
2516 WARN_ON(STp->buffer->do_dio != 0);
2517 if (STp->ready != ST_READY) {
2518 if (STp->ready == ST_NO_TAPE)
2519 return (-ENOMEDIUM);
2520 else
2521 return (-EIO);
2522 }
2523 timeout = STp->long_timeout;
2524 STps = &(STp->ps[STp->partition]);
2525 fileno = STps->drv_file;
2526 blkno = STps->drv_block;
2527 at_sm = STps->at_sm;
2528
2529 memset(cmd, 0, MAX_COMMAND_SIZE);
2530 switch (cmd_in) {
2531 case MTFSFM:
2532 chg_eof = 0; /* Changed from the FSF after this */
2533 case MTFSF:
2534 cmd[0] = SPACE;
2535 cmd[1] = 0x01; /* Space FileMarks */
2536 cmd[2] = (arg >> 16);
2537 cmd[3] = (arg >> 8);
2538 cmd[4] = arg;
2539 DEBC(deb_space_print(name, ST_DEB_FORWARD, "filemarks", cmd);)
2540 if (fileno >= 0)
2541 fileno += arg;
2542 blkno = 0;
2543 at_sm &= (arg == 0);
2544 break;
2545 case MTBSFM:
2546 chg_eof = 0; /* Changed from the FSF after this */
2547 case MTBSF:
2548 cmd[0] = SPACE;
2549 cmd[1] = 0x01; /* Space FileMarks */
2550 ltmp = (-arg);
2551 cmd[2] = (ltmp >> 16);
2552 cmd[3] = (ltmp >> 8);
2553 cmd[4] = ltmp;
2554 DEBC(deb_space_print(name, ST_DEB_BACKWARD, "filemarks", cmd);)
2555 if (fileno >= 0)
2556 fileno -= arg;
2557 blkno = (-1); /* We can't know the block number */
2558 at_sm &= (arg == 0);
2559 break;
2560 case MTFSR:
2561 cmd[0] = SPACE;
2562 cmd[1] = 0x00; /* Space Blocks */
2563 cmd[2] = (arg >> 16);
2564 cmd[3] = (arg >> 8);
2565 cmd[4] = arg;
2566 DEBC(deb_space_print(name, ST_DEB_FORWARD, "blocks", cmd);)
2567 if (blkno >= 0)
2568 blkno += arg;
2569 at_sm &= (arg == 0);
2570 break;
2571 case MTBSR:
2572 cmd[0] = SPACE;
2573 cmd[1] = 0x00; /* Space Blocks */
2574 ltmp = (-arg);
2575 cmd[2] = (ltmp >> 16);
2576 cmd[3] = (ltmp >> 8);
2577 cmd[4] = ltmp;
2578 DEBC(deb_space_print(name, ST_DEB_BACKWARD, "blocks", cmd);)
2579 if (blkno >= 0)
2580 blkno -= arg;
2581 at_sm &= (arg == 0);
2582 break;
2583 case MTFSS:
2584 cmd[0] = SPACE;
2585 cmd[1] = 0x04; /* Space Setmarks */
2586 cmd[2] = (arg >> 16);
2587 cmd[3] = (arg >> 8);
2588 cmd[4] = arg;
2589 DEBC(deb_space_print(name, ST_DEB_FORWARD, "setmarks", cmd);)
2590 if (arg != 0) {
2591 blkno = fileno = (-1);
2592 at_sm = 1;
2593 }
2594 break;
2595 case MTBSS:
2596 cmd[0] = SPACE;
2597 cmd[1] = 0x04; /* Space Setmarks */
2598 ltmp = (-arg);
2599 cmd[2] = (ltmp >> 16);
2600 cmd[3] = (ltmp >> 8);
2601 cmd[4] = ltmp;
2602 DEBC(deb_space_print(name, ST_DEB_BACKWARD, "setmarks", cmd);)
2603 if (arg != 0) {
2604 blkno = fileno = (-1);
2605 at_sm = 1;
2606 }
2607 break;
2608 case MTWEOF:
2609 case MTWSM:
2610 if (STp->write_prot)
2611 return (-EACCES);
2612 cmd[0] = WRITE_FILEMARKS;
2613 if (cmd_in == MTWSM)
2614 cmd[1] = 2;
2615 cmd[2] = (arg >> 16);
2616 cmd[3] = (arg >> 8);
2617 cmd[4] = arg;
2618 timeout = STp->device->timeout;
2619 DEBC(
2620 if (cmd_in == MTWEOF)
2621 printk(ST_DEB_MSG "%s: Writing %d filemarks.\n", name,
2622 cmd[2] * 65536 + cmd[3] * 256 + cmd[4]);
2623 else
2624 printk(ST_DEB_MSG "%s: Writing %d setmarks.\n", name,
2625 cmd[2] * 65536 + cmd[3] * 256 + cmd[4]);
2626 )
2627 if (fileno >= 0)
2628 fileno += arg;
2629 blkno = 0;
2630 at_sm = (cmd_in == MTWSM);
2631 break;
2632 case MTREW:
2633 cmd[0] = REZERO_UNIT;
2634 if (STp->immediate) {
2635 cmd[1] = 1; /* Don't wait for completion */
2636 timeout = STp->device->timeout;
2637 }
2638 DEBC(printk(ST_DEB_MSG "%s: Rewinding tape.\n", name));
2639 fileno = blkno = at_sm = 0;
2640 break;
2641 case MTNOP:
2642 DEBC(printk(ST_DEB_MSG "%s: No op on tape.\n", name));
2643 return 0; /* Should do something ? */
2644 break;
2645 case MTRETEN:
2646 cmd[0] = START_STOP;
2647 if (STp->immediate) {
2648 cmd[1] = 1; /* Don't wait for completion */
2649 timeout = STp->device->timeout;
2650 }
2651 cmd[4] = 3;
2652 DEBC(printk(ST_DEB_MSG "%s: Retensioning tape.\n", name));
2653 fileno = blkno = at_sm = 0;
2654 break;
2655 case MTEOM:
2656 if (!STp->fast_mteom) {
2657 /* space to the end of tape */
2658 ioctl_result = st_int_ioctl(STp, MTFSF, 0x7fffff);
2659 fileno = STps->drv_file;
2660 if (STps->eof >= ST_EOD_1)
2661 return 0;
2662 /* The next lines would hide the number of spaced FileMarks
2663 That's why I inserted the previous lines. I had no luck
2664 with detecting EOM with FSF, so we go now to EOM.
2665 Joerg Weule */
2666 } else
2667 fileno = (-1);
2668 cmd[0] = SPACE;
2669 cmd[1] = 3;
2670 DEBC(printk(ST_DEB_MSG "%s: Spacing to end of recorded medium.\n",
2671 name));
2672 blkno = -1;
2673 at_sm = 0;
2674 break;
2675 case MTERASE:
2676 if (STp->write_prot)
2677 return (-EACCES);
2678 cmd[0] = ERASE;
2679 cmd[1] = (arg ? 1 : 0); /* Long erase with non-zero argument */
2680 if (STp->immediate) {
2681 cmd[1] |= 2; /* Don't wait for completion */
2682 timeout = STp->device->timeout;
2683 }
2684 else
2685 timeout = STp->long_timeout * 8;
2686
2687 DEBC(printk(ST_DEB_MSG "%s: Erasing tape.\n", name));
2688 fileno = blkno = at_sm = 0;
2689 break;
2690 case MTSETBLK: /* Set block length */
2691 case MTSETDENSITY: /* Set tape density */
2692 case MTSETDRVBUFFER: /* Set drive buffering */
2693 case SET_DENS_AND_BLK: /* Set density and block size */
2694 chg_eof = 0;
2695 if (STp->dirty || (STp->buffer)->buffer_bytes != 0)
2696 return (-EIO); /* Not allowed if data in buffer */
2697 if ((cmd_in == MTSETBLK || cmd_in == SET_DENS_AND_BLK) &&
2698 (arg & MT_ST_BLKSIZE_MASK) != 0 &&
2699 STp->max_block > 0 &&
2700 ((arg & MT_ST_BLKSIZE_MASK) < STp->min_block ||
2701 (arg & MT_ST_BLKSIZE_MASK) > STp->max_block)) {
2702 printk(KERN_WARNING "%s: Illegal block size.\n", name);
2703 return (-EINVAL);
2704 }
2705 cmd[0] = MODE_SELECT;
2706 if ((STp->use_pf & USE_PF))
2707 cmd[1] = MODE_SELECT_PAGE_FORMAT;
2708 cmd[4] = datalen = 12;
2709 direction = DMA_TO_DEVICE;
2710
2711 memset((STp->buffer)->b_data, 0, 12);
2712 if (cmd_in == MTSETDRVBUFFER)
2713 (STp->buffer)->b_data[2] = (arg & 7) << 4;
2714 else
2715 (STp->buffer)->b_data[2] =
2716 STp->drv_buffer << 4;
2717 (STp->buffer)->b_data[3] = 8; /* block descriptor length */
2718 if (cmd_in == MTSETDENSITY) {
2719 (STp->buffer)->b_data[4] = arg;
2720 STp->density_changed = 1; /* At least we tried ;-) */
2721 } else if (cmd_in == SET_DENS_AND_BLK)
2722 (STp->buffer)->b_data[4] = arg >> 24;
2723 else
2724 (STp->buffer)->b_data[4] = STp->density;
2725 if (cmd_in == MTSETBLK || cmd_in == SET_DENS_AND_BLK) {
2726 ltmp = arg & MT_ST_BLKSIZE_MASK;
2727 if (cmd_in == MTSETBLK)
2728 STp->blksize_changed = 1; /* At least we tried ;-) */
2729 } else
2730 ltmp = STp->block_size;
2731 (STp->buffer)->b_data[9] = (ltmp >> 16);
2732 (STp->buffer)->b_data[10] = (ltmp >> 8);
2733 (STp->buffer)->b_data[11] = ltmp;
2734 timeout = STp->device->timeout;
2735 DEBC(
2736 if (cmd_in == MTSETBLK || cmd_in == SET_DENS_AND_BLK)
2737 printk(ST_DEB_MSG
2738 "%s: Setting block size to %d bytes.\n", name,
2739 (STp->buffer)->b_data[9] * 65536 +
2740 (STp->buffer)->b_data[10] * 256 +
2741 (STp->buffer)->b_data[11]);
2742 if (cmd_in == MTSETDENSITY || cmd_in == SET_DENS_AND_BLK)
2743 printk(ST_DEB_MSG
2744 "%s: Setting density code to %x.\n", name,
2745 (STp->buffer)->b_data[4]);
2746 if (cmd_in == MTSETDRVBUFFER)
2747 printk(ST_DEB_MSG
2748 "%s: Setting drive buffer code to %d.\n", name,
2749 ((STp->buffer)->b_data[2] >> 4) & 7);
2750 )
2751 break;
2752 default:
2753 return (-ENOSYS);
2754 }
2755
2756 SRpnt = st_do_scsi(NULL, STp, cmd, datalen, direction,
2757 timeout, MAX_RETRIES, 1);
2758 if (!SRpnt)
2759 return (STp->buffer)->syscall_result;
2760
2761 ioctl_result = (STp->buffer)->syscall_result;
2762
2763 if (!ioctl_result) { /* SCSI command successful */
8b05b773 2764 st_release_request(SRpnt);
1da177e4
LT		 2765 SRpnt = NULL;
2766 STps->drv_block = blkno;
2767 STps->drv_file = fileno;
2768 STps->at_sm = at_sm;
2769
2770 if (cmd_in == MTBSFM)
2771 ioctl_result = st_int_ioctl(STp, MTFSF, 1);
2772 else if (cmd_in == MTFSFM)
2773 ioctl_result = st_int_ioctl(STp, MTBSF, 1);
2774
2775 if (cmd_in == MTSETBLK || cmd_in == SET_DENS_AND_BLK) {
2776 int old_block_size = STp->block_size;
2777 STp->block_size = arg & MT_ST_BLKSIZE_MASK;
2778 if (STp->block_size != 0) {
2779 if (old_block_size == 0)
2780 normalize_buffer(STp->buffer);
2781 (STp->buffer)->buffer_blocks =
2782 (STp->buffer)->buffer_size / STp->block_size;
2783 }
2784 (STp->buffer)->buffer_bytes = (STp->buffer)->read_pointer = 0;
2785 if (cmd_in == SET_DENS_AND_BLK)
2786 STp->density = arg >> MT_ST_DENSITY_SHIFT;
2787 } else if (cmd_in == MTSETDRVBUFFER)
2788 STp->drv_buffer = (arg & 7);
2789 else if (cmd_in == MTSETDENSITY)
2790 STp->density = arg;
2791
2792 if (cmd_in == MTEOM)
2793 STps->eof = ST_EOD;
2794 else if (cmd_in == MTFSF)
2795 STps->eof = ST_FM;
2796 else if (chg_eof)
2797 STps->eof = ST_NOEOF;
2798
2799 if (cmd_in == MTWEOF)
2800 STps->rw = ST_IDLE;
2801 } else { /* SCSI command was not completely successful. Don't return
2802 from this block without releasing the SCSI command block! */
2803 struct st_cmdstatus *cmdstatp = &STp->buffer->cmdstat;
2804
2805 if (cmdstatp->flags & SENSE_EOM) {
2806 if (cmd_in != MTBSF && cmd_in != MTBSFM &&
2807 cmd_in != MTBSR && cmd_in != MTBSS)
2808 STps->eof = ST_EOM_OK;
2809 STps->drv_block = 0;
2810 }
2811
2812 if (cmdstatp->remainder_valid)
2813 undone = (int)cmdstatp->uremainder64;
2814 else
2815 undone = 0;
2816
2817 if (cmd_in == MTWEOF &&
2818 cmdstatp->have_sense &&
2819 (cmdstatp->flags & SENSE_EOM) &&
2820 (cmdstatp->sense_hdr.sense_key == NO_SENSE ||
2821 cmdstatp->sense_hdr.sense_key == RECOVERED_ERROR) &&
2822 undone == 0) {
d6e05edc 2823 ioctl_result = 0; /* EOF written successfully at EOM */
1da177e4
LT		 2824 if (fileno >= 0)
2825 fileno++;
2826 STps->drv_file = fileno;
2827 STps->eof = ST_NOEOF;
2828 } else if ((cmd_in == MTFSF) || (cmd_in == MTFSFM)) {
2829 if (fileno >= 0)
2830 STps->drv_file = fileno - undone;
2831 else
2832 STps->drv_file = fileno;
2833 STps->drv_block = -1;
2834 STps->eof = ST_NOEOF;
2835 } else if ((cmd_in == MTBSF) || (cmd_in == MTBSFM)) {
2836 if (arg > 0 && undone < 0) /* Some drives get this wrong */
2837 undone = (-undone);
2838 if (STps->drv_file >= 0)
2839 STps->drv_file = fileno + undone;
2840 STps->drv_block = 0;
2841 STps->eof = ST_NOEOF;
2842 } else if (cmd_in == MTFSR) {
2843 if (cmdstatp->flags & SENSE_FMK) { /* Hit filemark */
2844 if (STps->drv_file >= 0)
2845 STps->drv_file++;
2846 STps->drv_block = 0;
2847 STps->eof = ST_FM;
2848 } else {
2849 if (blkno >= undone)
2850 STps->drv_block = blkno - undone;
2851 else
2852 STps->drv_block = (-1);
2853 STps->eof = ST_NOEOF;
2854 }
2855 } else if (cmd_in == MTBSR) {
2856 if (cmdstatp->flags & SENSE_FMK) { /* Hit filemark */
2857 STps->drv_file--;
2858 STps->drv_block = (-1);
2859 } else {
2860 if (arg > 0 && undone < 0) /* Some drives get this wrong */
2861 undone = (-undone);
2862 if (STps->drv_block >= 0)
2863 STps->drv_block = blkno + undone;
2864 }
2865 STps->eof = ST_NOEOF;
2866 } else if (cmd_in == MTEOM) {
2867 STps->drv_file = (-1);
2868 STps->drv_block = (-1);
2869 STps->eof = ST_EOD;
2870 } else if (cmd_in == MTSETBLK ||
2871 cmd_in == MTSETDENSITY ||
2872 cmd_in == MTSETDRVBUFFER ||
2873 cmd_in == SET_DENS_AND_BLK) {
2874 if (cmdstatp->sense_hdr.sense_key == ILLEGAL_REQUEST &&
2875 !(STp->use_pf & PF_TESTED)) {
2876 /* Try the other possible state of Page Format if not
2877 already tried */
2878 STp->use_pf = !STp->use_pf | PF_TESTED;
8b05b773 2879 st_release_request(SRpnt);
1da177e4
LT		 2880 SRpnt = NULL;
2881 return st_int_ioctl(STp, cmd_in, arg);
2882 }
2883 } else if (chg_eof)
2884 STps->eof = ST_NOEOF;
2885
2886 if (cmdstatp->sense_hdr.sense_key == BLANK_CHECK)
2887 STps->eof = ST_EOD;
2888
8b05b773 2889 st_release_request(SRpnt);
1da177e4
LT		 2890 SRpnt = NULL;
2891 }
2892
2893 return ioctl_result;
2894}
2895\f
2896
2897/* Get the tape position. If bt == 2, arg points into a kernel space mt_loc
2898 structure. */
2899
2900static int get_location(struct scsi_tape *STp, unsigned int *block, int *partition,
2901 int logical)
2902{
2903 int result;
2904 unsigned char scmd[MAX_COMMAND_SIZE];
8b05b773 2905 struct st_request *SRpnt;
1da177e4
LT		 2906 DEB( char *name = tape_name(STp); )
2907
2908 if (STp->ready != ST_READY)
2909 return (-EIO);
2910
2911 memset(scmd, 0, MAX_COMMAND_SIZE);
2912 if ((STp->device)->scsi_level < SCSI_2) {
2913 scmd[0] = QFA_REQUEST_BLOCK;
2914 scmd[4] = 3;
2915 } else {
2916 scmd[0] = READ_POSITION;
2917 if (!logical && !STp->scsi2_logical)
2918 scmd[1] = 1;
2919 }
2920 SRpnt = st_do_scsi(NULL, STp, scmd, 20, DMA_FROM_DEVICE,
2921 STp->device->timeout, MAX_READY_RETRIES, 1);
2922 if (!SRpnt)
2923 return (STp->buffer)->syscall_result;
2924
2925 if ((STp->buffer)->syscall_result != 0 ||
2926 (STp->device->scsi_level >= SCSI_2 &&
2927 ((STp->buffer)->b_data[0] & 4) != 0)) {
2928 *block = *partition = 0;
2929 DEBC(printk(ST_DEB_MSG "%s: Can't read tape position.\n", name));
2930 result = (-EIO);
2931 } else {
2932 result = 0;
2933 if ((STp->device)->scsi_level < SCSI_2) {
2934 *block = ((STp->buffer)->b_data[0] << 16)
2935 + ((STp->buffer)->b_data[1] << 8)
2936 + (STp->buffer)->b_data[2];
2937 *partition = 0;
2938 } else {
2939 *block = ((STp->buffer)->b_data[4] << 24)
2940 + ((STp->buffer)->b_data[5] << 16)
2941 + ((STp->buffer)->b_data[6] << 8)
2942 + (STp->buffer)->b_data[7];
2943 *partition = (STp->buffer)->b_data[1];
2944 if (((STp->buffer)->b_data[0] & 0x80) &&
2945 (STp->buffer)->b_data[1] == 0) /* BOP of partition 0 */
2946 STp->ps[0].drv_block = STp->ps[0].drv_file = 0;
2947 }
2948 DEBC(printk(ST_DEB_MSG "%s: Got tape pos. blk %d part %d.\n", name,
2949 *block, *partition));
2950 }
8b05b773 2951 st_release_request(SRpnt);
1da177e4
LT		 2952 SRpnt = NULL;
2953
2954 return result;
2955}
2956
2957
2958/* Set the tape block and partition. Negative partition means that only the
2959 block should be set in vendor specific way. */
2960static int set_location(struct scsi_tape *STp, unsigned int block, int partition,
2961 int logical)
2962{
2963 struct st_partstat *STps;
2964 int result, p;
2965 unsigned int blk;
2966 int timeout;
2967 unsigned char scmd[MAX_COMMAND_SIZE];
8b05b773 2968 struct st_request *SRpnt;
1da177e4
LT		 2969 DEB( char *name = tape_name(STp); )
2970
2971 if (STp->ready != ST_READY)
2972 return (-EIO);
2973 timeout = STp->long_timeout;
2974 STps = &(STp->ps[STp->partition]);
2975
2976 DEBC(printk(ST_DEB_MSG "%s: Setting block to %d and partition to %d.\n",
2977 name, block, partition));
2978 DEB(if (partition < 0)
2979 return (-EIO); )
2980
2981 /* Update the location at the partition we are leaving */
2982 if ((!STp->can_partitions && partition != 0) ||
2983 partition >= ST_NBR_PARTITIONS)
2984 return (-EINVAL);
2985 if (partition != STp->partition) {
2986 if (get_location(STp, &blk, &p, 1))
2987 STps->last_block_valid = 0;
2988 else {
2989 STps->last_block_valid = 1;
2990 STps->last_block_visited = blk;
2991 DEBC(printk(ST_DEB_MSG
2992 "%s: Visited block %d for partition %d saved.\n",
2993 name, blk, STp->partition));
2994 }
2995 }
2996
2997 memset(scmd, 0, MAX_COMMAND_SIZE);
2998 if ((STp->device)->scsi_level < SCSI_2) {
2999 scmd[0] = QFA_SEEK_BLOCK;
3000 scmd[2] = (block >> 16);
3001 scmd[3] = (block >> 8);
3002 scmd[4] = block;
3003 scmd[5] = 0;
3004 } else {
3005 scmd[0] = SEEK_10;
3006 scmd[3] = (block >> 24);
3007 scmd[4] = (block >> 16);
3008 scmd[5] = (block >> 8);
3009 scmd[6] = block;
3010 if (!logical && !STp->scsi2_logical)
3011 scmd[1] = 4;
3012 if (STp->partition != partition) {
3013 scmd[1] |= 2;
3014 scmd[8] = partition;
3015 DEBC(printk(ST_DEB_MSG
3016 "%s: Trying to change partition from %d to %d\n",
3017 name, STp->partition, partition));
3018 }
3019 }
3020 if (STp->immediate) {
3021 scmd[1] |= 1; /* Don't wait for completion */
3022 timeout = STp->device->timeout;
3023 }
3024
3025 SRpnt = st_do_scsi(NULL, STp, scmd, 0, DMA_NONE,
3026 timeout, MAX_READY_RETRIES, 1);
3027 if (!SRpnt)
3028 return (STp->buffer)->syscall_result;
3029
3030 STps->drv_block = STps->drv_file = (-1);
3031 STps->eof = ST_NOEOF;
3032 if ((STp->buffer)->syscall_result != 0) {
3033 result = (-EIO);
3034 if (STp->can_partitions &&
3035 (STp->device)->scsi_level >= SCSI_2 &&
3036 (p = find_partition(STp)) >= 0)
3037 STp->partition = p;
3038 } else {
3039 if (STp->can_partitions) {
3040 STp->partition = partition;
3041 STps = &(STp->ps[partition]);
3042 if (!STps->last_block_valid ||
3043 STps->last_block_visited != block) {
3044 STps->at_sm = 0;
3045 STps->rw = ST_IDLE;
3046 }
3047 } else
3048 STps->at_sm = 0;
3049 if (block == 0)
3050 STps->drv_block = STps->drv_file = 0;
3051 result = 0;
3052 }
3053
8b05b773 3054 st_release_request(SRpnt);
1da177e4
LT		 3055 SRpnt = NULL;
3056
3057 return result;
3058}
3059
3060
3061/* Find the current partition number for the drive status. Called from open and
3062 returns either partition number of negative error code. */
3063static int find_partition(struct scsi_tape *STp)
3064{
3065 int i, partition;
3066 unsigned int block;
3067
3068 if ((i = get_location(STp, &block, &partition, 1)) < 0)
3069 return i;
3070 if (partition >= ST_NBR_PARTITIONS)
3071 return (-EIO);
3072 return partition;
3073}
3074
3075
3076/* Change the partition if necessary */
3077static int switch_partition(struct scsi_tape *STp)
3078{
3079 struct st_partstat *STps;
3080
3081 if (STp->partition == STp->new_partition)
3082 return 0;
3083 STps = &(STp->ps[STp->new_partition]);
3084 if (!STps->last_block_valid)
3085 STps->last_block_visited = 0;
3086 return set_location(STp, STps->last_block_visited, STp->new_partition, 1);
3087}
3088\f
3089/* Functions for reading and writing the medium partition mode page. */
3090
3091#define PART_PAGE 0x11
3092#define PART_PAGE_FIXED_LENGTH 8
3093
3094#define PP_OFF_MAX_ADD_PARTS 2
3095#define PP_OFF_NBR_ADD_PARTS 3
3096#define PP_OFF_FLAGS 4
3097#define PP_OFF_PART_UNITS 6
3098#define PP_OFF_RESERVED 7
3099
3100#define PP_BIT_IDP 0x20
3101#define PP_MSK_PSUM_MB 0x10
3102
3103/* Get the number of partitions on the tape. As a side effect reads the
3104 mode page into the tape buffer. */
3105static int nbr_partitions(struct scsi_tape *STp)
3106{
3107 int result;
3108 DEB( char *name = tape_name(STp); )
3109
3110 if (STp->ready != ST_READY)
3111 return (-EIO);
3112
3113 result = read_mode_page(STp, PART_PAGE, 1);
3114
3115 if (result) {
3116 DEBC(printk(ST_DEB_MSG "%s: Can't read medium partition page.\n",
3117 name));
3118 result = (-EIO);
3119 } else {
3120 result = (STp->buffer)->b_data[MODE_HEADER_LENGTH +
3121 PP_OFF_NBR_ADD_PARTS] + 1;
3122 DEBC(printk(ST_DEB_MSG "%s: Number of partitions %d.\n", name, result));
3123 }
3124
3125 return result;
3126}
3127
3128
3129/* Partition the tape into two partitions if size > 0 or one partition if
3130 size == 0.
3131
3132 The block descriptors are read and written because Sony SDT-7000 does not
3133 work without this (suggestion from Michael Schaefer <Michael.Schaefer@dlr.de>).
3134
3135 My HP C1533A drive returns only one partition size field. This is used to
3136 set the size of partition 1. There is no size field for the default partition.
3137 Michael Schaefer's Sony SDT-7000 returns two descriptors and the second is
3138 used to set the size of partition 1 (this is what the SCSI-3 standard specifies).
3139 The following algorithm is used to accommodate both drives: if the number of
3140 partition size fields is greater than the maximum number of additional partitions
3141 in the mode page, the second field is used. Otherwise the first field is used.
3142
3143 For Seagate DDS drives the page length must be 8 when no partitions is defined
3144 and 10 when 1 partition is defined (information from Eric Lee Green). This is
3145 is acceptable also to some other old drives and enforced if the first partition
3146 size field is used for the first additional partition size.
3147 */
3148static int partition_tape(struct scsi_tape *STp, int size)
3149{
3150 char *name = tape_name(STp);
3151 int result;
3152 int pgo, psd_cnt, psdo;
3153 unsigned char *bp;
3154
3155 result = read_mode_page(STp, PART_PAGE, 0);
3156 if (result) {
3157 DEBC(printk(ST_DEB_MSG "%s: Can't read partition mode page.\n", name));
3158 return result;
3159 }
3160 /* The mode page is in the buffer. Let's modify it and write it. */
3161 bp = (STp->buffer)->b_data;
3162 pgo = MODE_HEADER_LENGTH + bp[MH_OFF_BDESCS_LENGTH];
3163 DEBC(printk(ST_DEB_MSG "%s: Partition page length is %d bytes.\n",
3164 name, bp[pgo + MP_OFF_PAGE_LENGTH] + 2));
3165
3166 psd_cnt = (bp[pgo + MP_OFF_PAGE_LENGTH] + 2 - PART_PAGE_FIXED_LENGTH) / 2;
3167 psdo = pgo + PART_PAGE_FIXED_LENGTH;
3168 if (psd_cnt > bp[pgo + PP_OFF_MAX_ADD_PARTS]) {
3169 bp[psdo] = bp[psdo + 1] = 0xff; /* Rest of the tape */
3170 psdo += 2;
3171 }
3172 memset(bp + psdo, 0, bp[pgo + PP_OFF_NBR_ADD_PARTS] * 2);
3173
3174 DEBC(printk("%s: psd_cnt %d, max.parts %d, nbr_parts %d\n", name,
3175 psd_cnt, bp[pgo + PP_OFF_MAX_ADD_PARTS],
3176 bp[pgo + PP_OFF_NBR_ADD_PARTS]));
3177
3178 if (size <= 0) {
3179 bp[pgo + PP_OFF_NBR_ADD_PARTS] = 0;
3180 if (psd_cnt <= bp[pgo + PP_OFF_MAX_ADD_PARTS])
3181 bp[pgo + MP_OFF_PAGE_LENGTH] = 6;
3182 DEBC(printk(ST_DEB_MSG "%s: Formatting tape with one partition.\n",
3183 name));
3184 } else {
3185 bp[psdo] = (size >> 8) & 0xff;
3186 bp[psdo + 1] = size & 0xff;
3187 bp[pgo + 3] = 1;
3188 if (bp[pgo + MP_OFF_PAGE_LENGTH] < 8)
3189 bp[pgo + MP_OFF_PAGE_LENGTH] = 8;
3190 DEBC(printk(ST_DEB_MSG
3191 "%s: Formatting tape with two partitions (1 = %d MB).\n",
3192 name, size));
3193 }
3194 bp[pgo + PP_OFF_PART_UNITS] = 0;
3195 bp[pgo + PP_OFF_RESERVED] = 0;
3196 bp[pgo + PP_OFF_FLAGS] = PP_BIT_IDP | PP_MSK_PSUM_MB;
3197
3198 result = write_mode_page(STp, PART_PAGE, 1);
3199 if (result) {
3200 printk(KERN_INFO "%s: Partitioning of tape failed.\n", name);
3201 result = (-EIO);
3202 }
3203
3204 return result;
3205}
3206\f
3207
3208
3209/* The ioctl command */
3210static int st_ioctl(struct inode *inode, struct file *file,
3211 unsigned int cmd_in, unsigned long arg)
3212{
3213 int i, cmd_nr, cmd_type, bt;
3214 int retval = 0;
3215 unsigned int blk;
3216 struct scsi_tape *STp = file->private_data;
3217 struct st_modedef *STm;
3218 struct st_partstat *STps;
3219 char *name = tape_name(STp);
3220 void __user *p = (void __user *)arg;
3221
3222 if (down_interruptible(&STp->lock))
3223 return -ERESTARTSYS;
3224
3225 DEB(
3226 if (debugging && !STp->in_use) {
3227 printk(ST_DEB_MSG "%s: Incorrect device.\n", name);
3228 retval = (-EIO);
3229 goto out;
3230 } ) /* end DEB */
3231
3232 STm = &(STp->modes[STp->current_mode]);
3233 STps = &(STp->ps[STp->partition]);
3234
3235 /*
3236 * If we are in the middle of error recovery, don't let anyone
3237 * else try and use this device. Also, if error recovery fails, it
3238 * may try and take the device offline, in which case all further
3239 * access to the device is prohibited.
3240 */
3241 retval = scsi_nonblockable_ioctl(STp->device, cmd_in, p, file);
3242 if (!scsi_block_when_processing_errors(STp->device) || retval != -ENODEV)
3243 goto out;
3244 retval = 0;
3245
3246 cmd_type = _IOC_TYPE(cmd_in);
3247 cmd_nr = _IOC_NR(cmd_in);
3248
3249 if (cmd_type == _IOC_TYPE(MTIOCTOP) && cmd_nr == _IOC_NR(MTIOCTOP)) {
3250 struct mtop mtc;
3251
3252 if (_IOC_SIZE(cmd_in) != sizeof(mtc)) {
3253 retval = (-EINVAL);
3254 goto out;
3255 }
3256
3257 i = copy_from_user(&mtc, p, sizeof(struct mtop));
3258 if (i) {
3259 retval = (-EFAULT);
3260 goto out;
3261 }
3262
3263 if (mtc.mt_op == MTSETDRVBUFFER && !capable(CAP_SYS_ADMIN)) {
3264 printk(KERN_WARNING
3265 "%s: MTSETDRVBUFFER only allowed for root.\n", name);
3266 retval = (-EPERM);
3267 goto out;
3268 }
3269 if (!STm->defined &&
3270 (mtc.mt_op != MTSETDRVBUFFER &&
3271 (mtc.mt_count & MT_ST_OPTIONS) == 0)) {
3272 retval = (-ENXIO);
3273 goto out;
3274 }
3275
3276 if (!STp->pos_unknown) {
3277
3278 if (STps->eof == ST_FM_HIT) {
3279 if (mtc.mt_op == MTFSF || mtc.mt_op == MTFSFM ||
3280 mtc.mt_op == MTEOM) {
3281 mtc.mt_count -= 1;
3282 if (STps->drv_file >= 0)
3283 STps->drv_file += 1;
3284 } else if (mtc.mt_op == MTBSF || mtc.mt_op == MTBSFM) {
3285 mtc.mt_count += 1;
3286 if (STps->drv_file >= 0)
3287 STps->drv_file += 1;
3288 }
3289 }
3290
3291 if (mtc.mt_op == MTSEEK) {
3292 /* Old position must be restored if partition will be
3293 changed */
3294 i = !STp->can_partitions ||
3295 (STp->new_partition != STp->partition);
3296 } else {
3297 i = mtc.mt_op == MTREW || mtc.mt_op == MTOFFL ||
3298 mtc.mt_op == MTRETEN || mtc.mt_op == MTEOM ||
3299 mtc.mt_op == MTLOCK || mtc.mt_op == MTLOAD ||
3300 mtc.mt_op == MTFSF || mtc.mt_op == MTFSFM ||
3301 mtc.mt_op == MTBSF || mtc.mt_op == MTBSFM ||
3302 mtc.mt_op == MTCOMPRESSION;
3303 }
3304 i = flush_buffer(STp, i);
3305 if (i < 0) {
3306 retval = i;
3307 goto out;
3308 }
3309 if (STps->rw == ST_WRITING &&
3310 (mtc.mt_op == MTREW || mtc.mt_op == MTOFFL ||
3311 mtc.mt_op == MTSEEK ||
3312 mtc.mt_op == MTBSF || mtc.mt_op == MTBSFM)) {
3313 i = st_int_ioctl(STp, MTWEOF, 1);
3314 if (i < 0) {
3315 retval = i;
3316 goto out;
3317 }
3318 if (mtc.mt_op == MTBSF || mtc.mt_op == MTBSFM)
3319 mtc.mt_count++;
3320 STps->rw = ST_IDLE;
3321 }
3322
3323 } else {
3324 /*
3325 * If there was a bus reset, block further access
3326 * to this device. If the user wants to rewind the tape,
3327 * then reset the flag and allow access again.
3328 */
3329 if (mtc.mt_op != MTREW &&
3330 mtc.mt_op != MTOFFL &&
3331 mtc.mt_op != MTRETEN &&
3332 mtc.mt_op != MTERASE &&
3333 mtc.mt_op != MTSEEK &&
3334 mtc.mt_op != MTEOM) {
3335 retval = (-EIO);
3336 goto out;
3337 }
3338 reset_state(STp);
3339 /* remove this when the midlevel properly clears was_reset */
3340 STp->device->was_reset = 0;
3341 }
3342
3343 if (mtc.mt_op != MTNOP && mtc.mt_op != MTSETBLK &&
3344 mtc.mt_op != MTSETDENSITY && mtc.mt_op != MTWSM &&
3345 mtc.mt_op != MTSETDRVBUFFER && mtc.mt_op != MTSETPART)
3346 STps->rw = ST_IDLE; /* Prevent automatic WEOF and fsf */
3347
3348 if (mtc.mt_op == MTOFFL && STp->door_locked != ST_UNLOCKED)
3349 do_door_lock(STp, 0); /* Ignore result! */
3350
3351 if (mtc.mt_op == MTSETDRVBUFFER &&
3352 (mtc.mt_count & MT_ST_OPTIONS) != 0) {
3353 retval = st_set_options(STp, mtc.mt_count);
3354 goto out;
3355 }
3356
3357 if (mtc.mt_op == MTSETPART) {
3358 if (!STp->can_partitions ||
3359 mtc.mt_count < 0 || mtc.mt_count >= ST_NBR_PARTITIONS) {
3360 retval = (-EINVAL);
3361 goto out;
3362 }
3363 if (mtc.mt_count >= STp->nbr_partitions &&
3364 (STp->nbr_partitions = nbr_partitions(STp)) < 0) {
3365 retval = (-EIO);
3366 goto out;
3367 }
3368 if (mtc.mt_count >= STp->nbr_partitions) {
3369 retval = (-EINVAL);
3370 goto out;
3371 }
3372 STp->new_partition = mtc.mt_count;
3373 retval = 0;
3374 goto out;
3375 }
3376
3377 if (mtc.mt_op == MTMKPART) {
3378 if (!STp->can_partitions) {
3379 retval = (-EINVAL);
3380 goto out;
3381 }
3382 if ((i = st_int_ioctl(STp, MTREW, 0)) < 0 ||
3383 (i = partition_tape(STp, mtc.mt_count)) < 0) {
3384 retval = i;
3385 goto out;
3386 }
3387 for (i = 0; i < ST_NBR_PARTITIONS; i++) {
3388 STp->ps[i].rw = ST_IDLE;
3389 STp->ps[i].at_sm = 0;
3390 STp->ps[i].last_block_valid = 0;
3391 }
3392 STp->partition = STp->new_partition = 0;
3393 STp->nbr_partitions = 1; /* Bad guess ?-) */
3394 STps->drv_block = STps->drv_file = 0;
3395 retval = 0;
3396 goto out;
3397 }
3398
3399 if (mtc.mt_op == MTSEEK) {
3400 i = set_location(STp, mtc.mt_count, STp->new_partition, 0);
3401 if (!STp->can_partitions)
3402 STp->ps[0].rw = ST_IDLE;
3403 retval = i;
3404 goto out;
3405 }
3406
3407 if (mtc.mt_op == MTUNLOAD || mtc.mt_op == MTOFFL) {
3408 retval = do_load_unload(STp, file, 0);
3409 goto out;
3410 }
3411
3412 if (mtc.mt_op == MTLOAD) {
3413 retval = do_load_unload(STp, file, max(1, mtc.mt_count));
3414 goto out;
3415 }
3416
3417 if (mtc.mt_op == MTLOCK || mtc.mt_op == MTUNLOCK) {
3418 retval = do_door_lock(STp, (mtc.mt_op == MTLOCK));
3419 goto out;
3420 }
3421
3422 if (STp->can_partitions && STp->ready == ST_READY &&
3423 (i = switch_partition(STp)) < 0) {
3424 retval = i;
3425 goto out;
3426 }
3427
3428 if (mtc.mt_op == MTCOMPRESSION)
3429 retval = st_compression(STp, (mtc.mt_count & 1));
3430 else
3431 retval = st_int_ioctl(STp, mtc.mt_op, mtc.mt_count);
3432 goto out;
3433 }
3434 if (!STm->defined) {
3435 retval = (-ENXIO);
3436 goto out;
3437 }
3438
3439 if ((i = flush_buffer(STp, 0)) < 0) {
3440 retval = i;
3441 goto out;
3442 }
3443 if (STp->can_partitions &&
3444 (i = switch_partition(STp)) < 0) {
3445 retval = i;
3446 goto out;
3447 }
3448
3449 if (cmd_type == _IOC_TYPE(MTIOCGET) && cmd_nr == _IOC_NR(MTIOCGET)) {
3450 struct mtget mt_status;
3451
3452 if (_IOC_SIZE(cmd_in) != sizeof(struct mtget)) {
3453 retval = (-EINVAL);
3454 goto out;
3455 }
3456
3457 mt_status.mt_type = STp->tape_type;
3458 mt_status.mt_dsreg =
3459 ((STp->block_size << MT_ST_BLKSIZE_SHIFT) & MT_ST_BLKSIZE_MASK) |
3460 ((STp->density << MT_ST_DENSITY_SHIFT) & MT_ST_DENSITY_MASK);
3461 mt_status.mt_blkno = STps->drv_block;
3462 mt_status.mt_fileno = STps->drv_file;
3463 if (STp->block_size != 0) {
3464 if (STps->rw == ST_WRITING)
3465 mt_status.mt_blkno +=
3466 (STp->buffer)->buffer_bytes / STp->block_size;
3467 else if (STps->rw == ST_READING)
3468 mt_status.mt_blkno -=
3469 ((STp->buffer)->buffer_bytes +
3470 STp->block_size - 1) / STp->block_size;
3471 }
3472
3473 mt_status.mt_gstat = 0;
3474 if (STp->drv_write_prot)
3475 mt_status.mt_gstat |= GMT_WR_PROT(0xffffffff);
3476 if (mt_status.mt_blkno == 0) {
3477 if (mt_status.mt_fileno == 0)
3478 mt_status.mt_gstat |= GMT_BOT(0xffffffff);
3479 else
3480 mt_status.mt_gstat |= GMT_EOF(0xffffffff);
3481 }
3482 mt_status.mt_erreg = (STp->recover_reg << MT_ST_SOFTERR_SHIFT);
3483 mt_status.mt_resid = STp->partition;
3484 if (STps->eof == ST_EOM_OK || STps->eof == ST_EOM_ERROR)
3485 mt_status.mt_gstat |= GMT_EOT(0xffffffff);
3486 else if (STps->eof >= ST_EOM_OK)
3487 mt_status.mt_gstat |= GMT_EOD(0xffffffff);
3488 if (STp->density == 1)
3489 mt_status.mt_gstat |= GMT_D_800(0xffffffff);
3490 else if (STp->density == 2)
3491 mt_status.mt_gstat |= GMT_D_1600(0xffffffff);
3492 else if (STp->density == 3)
3493 mt_status.mt_gstat |= GMT_D_6250(0xffffffff);
3494 if (STp->ready == ST_READY)
3495 mt_status.mt_gstat |= GMT_ONLINE(0xffffffff);
3496 if (STp->ready == ST_NO_TAPE)
3497 mt_status.mt_gstat |= GMT_DR_OPEN(0xffffffff);
3498 if (STps->at_sm)
3499 mt_status.mt_gstat |= GMT_SM(0xffffffff);
3500 if (STm->do_async_writes ||
3501 (STm->do_buffer_writes && STp->block_size != 0) ||
3502 STp->drv_buffer != 0)
3503 mt_status.mt_gstat |= GMT_IM_REP_EN(0xffffffff);
3504 if (STp->cleaning_req)
3505 mt_status.mt_gstat |= GMT_CLN(0xffffffff);
3506
3507 i = copy_to_user(p, &mt_status, sizeof(struct mtget));
3508 if (i) {
3509 retval = (-EFAULT);
3510 goto out;
3511 }
3512
3513 STp->recover_reg = 0; /* Clear after read */
3514 retval = 0;
3515 goto out;
3516 } /* End of MTIOCGET */
3517 if (cmd_type == _IOC_TYPE(MTIOCPOS) && cmd_nr == _IOC_NR(MTIOCPOS)) {
3518 struct mtpos mt_pos;
3519 if (_IOC_SIZE(cmd_in) != sizeof(struct mtpos)) {
3520 retval = (-EINVAL);
3521 goto out;
3522 }
3523 if ((i = get_location(STp, &blk, &bt, 0)) < 0) {
3524 retval = i;
3525 goto out;
3526 }
3527 mt_pos.mt_blkno = blk;
3528 i = copy_to_user(p, &mt_pos, sizeof(struct mtpos));
3529 if (i)
3530 retval = (-EFAULT);
3531 goto out;
3532 }
3533 up(&STp->lock);
3534 switch (cmd_in) {
3535 case SCSI_IOCTL_GET_IDLUN:
3536 case SCSI_IOCTL_GET_BUS_NUMBER:
3537 break;
3538 default:
16c4b3e2
KM		 3539 if ((cmd_in == SG_IO ||
3540 cmd_in == SCSI_IOCTL_SEND_COMMAND ||
3541 cmd_in == CDROM_SEND_PACKET) &&
3542 !capable(CAP_SYS_RAWIO))
1da177e4
LT		 3543 i = -EPERM;
3544 else
3545 i = scsi_cmd_ioctl(file, STp->disk, cmd_in, p);
3546 if (i != -ENOTTY)
3547 return i;
3548 break;
3549 }
16c4b3e2
KM		 3550 retval = scsi_ioctl(STp->device, cmd_in, p);
3551 if (!retval && cmd_in == SCSI_IOCTL_STOP_UNIT) { /* unload */
3552 STp->rew_at_close = 0;
3553 STp->ready = ST_NO_TAPE;
3554 }
3555 return retval;
1da177e4
LT		 3556
3557 out:
3558 up(&STp->lock);
3559 return retval;
3560}
3561
3562#ifdef CONFIG_COMPAT
3563static long st_compat_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
3564{
3565 struct scsi_tape *STp = file->private_data;
3566 struct scsi_device *sdev = STp->device;
3567 int ret = -ENOIOCTLCMD;
3568 if (sdev->host->hostt->compat_ioctl) {
3569
3570 ret = sdev->host->hostt->compat_ioctl(sdev, cmd, (void __user *)arg);
3571
3572 }
3573 return ret;
3574}
3575#endif
3576
3577\f
3578
3579/* Try to allocate a new tape buffer. Calling function must not hold
3580 dev_arr_lock. */
3581static struct st_buffer *
3582 new_tape_buffer(int from_initialization, int need_dma, int max_sg)
3583{
8b05b773 3584 int i, got = 0;
c53033f6 3585 gfp_t priority;
1da177e4
LT		 3586 struct st_buffer *tb;
3587
3588 if (from_initialization)
3589 priority = GFP_ATOMIC;
3590 else
3591 priority = GFP_KERNEL;
3592
3593 i = sizeof(struct st_buffer) + (max_sg - 1) * sizeof(struct scatterlist) +
3594 max_sg * sizeof(struct st_buf_fragment);
24669f75 3595 tb = kzalloc(i, priority);
1da177e4
LT		 3596 if (!tb) {
3597 printk(KERN_NOTICE "st: Can't allocate new tape buffer.\n");
3598 return NULL;
3599 }
8b05b773 3600 tb->frp_segs = tb->orig_frp_segs = 0;
1da177e4 3601 tb->use_sg = max_sg;
1da177e4
LT		 3602 tb->frp = (struct st_buf_fragment *)(&(tb->sg[0]) + max_sg);
3603
1da177e4
LT		 3604 tb->dma = need_dma;
3605 tb->buffer_size = got;
3606
3607 return tb;
3608}
3609
3610
3611/* Try to allocate enough space in the tape buffer */
3612static int enlarge_buffer(struct st_buffer * STbuffer, int new_size, int need_dma)
3613{
c53033f6
AV		 3614 int segs, nbr, max_segs, b_size, order, got;
3615 gfp_t priority;
1da177e4
LT		 3616
3617 if (new_size <= STbuffer->buffer_size)
3618 return 1;
3619
3620 if (STbuffer->buffer_size <= PAGE_SIZE)
3621 normalize_buffer(STbuffer); /* Avoid extra segment */
3622
3623 max_segs = STbuffer->use_sg;
3624 nbr = max_segs - STbuffer->frp_segs;
3625 if (nbr <= 0)
3626 return 0;
3627
3628 priority = GFP_KERNEL | __GFP_NOWARN;
3629 if (need_dma)
3630 priority |= GFP_DMA;
8b05b773 3631 for (b_size = PAGE_SIZE, order=0; order <= 6 &&
1da177e4
LT		 3632 b_size < new_size - STbuffer->buffer_size;
3633 order++, b_size *= 2)
3634 ; /* empty */
3635
3636 for (segs = STbuffer->frp_segs, got = STbuffer->buffer_size;
3637 segs < max_segs && got < new_size;) {
3638 STbuffer->frp[segs].page = alloc_pages(priority, order);
3639 if (STbuffer->frp[segs].page == NULL) {
3640 if (new_size - got <= (max_segs - segs) * b_size / 2) {
3641 b_size /= 2; /* Large enough for the rest of the buffers */
3642 order--;
3643 continue;
3644 }
3645 DEB(STbuffer->buffer_size = got);
3646 normalize_buffer(STbuffer);
3647 return 0;
3648 }
3649 STbuffer->frp[segs].length = b_size;
3650 STbuffer->frp_segs += 1;
3651 got += b_size;
3652 STbuffer->buffer_size = got;
3653 segs++;
3654 }
3655 STbuffer->b_data = page_address(STbuffer->frp[0].page);
3656
3657 return 1;
3658}
3659
3660
3661/* Release the extra buffer */
3662static void normalize_buffer(struct st_buffer * STbuffer)
3663{
3664 int i, order;
3665
3666 for (i = STbuffer->orig_frp_segs; i < STbuffer->frp_segs; i++) {
3667 order = get_order(STbuffer->frp[i].length);
3668 __free_pages(STbuffer->frp[i].page, order);
3669 STbuffer->buffer_size -= STbuffer->frp[i].length;
3670 }
3671 STbuffer->frp_segs = STbuffer->orig_frp_segs;
3672 STbuffer->frp_sg_current = 0;
8b05b773 3673 STbuffer->sg_segs = 0;
1da177e4
LT		 3674}
3675
3676
3677/* Move data from the user buffer to the tape buffer. Returns zero (success) or
3678 negative error code. */
3679static int append_to_buffer(const char __user *ubp, struct st_buffer * st_bp, int do_count)
3680{
3681 int i, cnt, res, offset;
3682
3683 for (i = 0, offset = st_bp->buffer_bytes;
3684 i < st_bp->frp_segs && offset >= st_bp->frp[i].length; i++)
3685 offset -= st_bp->frp[i].length;
3686 if (i == st_bp->frp_segs) { /* Should never happen */
3687 printk(KERN_WARNING "st: append_to_buffer offset overflow.\n");
3688 return (-EIO);
3689 }
3690 for (; i < st_bp->frp_segs && do_count > 0; i++) {
3691 cnt = st_bp->frp[i].length - offset < do_count ?
3692 st_bp->frp[i].length - offset : do_count;
3693 res = copy_from_user(page_address(st_bp->frp[i].page) + offset, ubp, cnt);
3694 if (res)
3695 return (-EFAULT);
3696 do_count -= cnt;
3697 st_bp->buffer_bytes += cnt;
3698 ubp += cnt;
3699 offset = 0;
3700 }
3701 if (do_count) /* Should never happen */
3702 return (-EIO);
3703
3704 return 0;
3705}
3706
3707
3708/* Move data from the tape buffer to the user buffer. Returns zero (success) or
3709 negative error code. */
3710static int from_buffer(struct st_buffer * st_bp, char __user *ubp, int do_count)
3711{
3712 int i, cnt, res, offset;
3713
3714 for (i = 0, offset = st_bp->read_pointer;
3715 i < st_bp->frp_segs && offset >= st_bp->frp[i].length; i++)
3716 offset -= st_bp->frp[i].length;
3717 if (i == st_bp->frp_segs) { /* Should never happen */
3718 printk(KERN_WARNING "st: from_buffer offset overflow.\n");
3719 return (-EIO);
3720 }
3721 for (; i < st_bp->frp_segs && do_count > 0; i++) {
3722 cnt = st_bp->frp[i].length - offset < do_count ?
3723 st_bp->frp[i].length - offset : do_count;
3724 res = copy_to_user(ubp, page_address(st_bp->frp[i].page) + offset, cnt);
3725 if (res)
3726 return (-EFAULT);
3727 do_count -= cnt;
3728 st_bp->buffer_bytes -= cnt;
3729 st_bp->read_pointer += cnt;
3730 ubp += cnt;
3731 offset = 0;
3732 }
3733 if (do_count) /* Should never happen */
3734 return (-EIO);
3735
3736 return 0;
3737}
3738
3739
3740/* Move data towards start of buffer */
3741static void move_buffer_data(struct st_buffer * st_bp, int offset)
3742{
3743 int src_seg, dst_seg, src_offset = 0, dst_offset;
3744 int count, total;
3745
3746 if (offset == 0)
3747 return;
3748
3749 total=st_bp->buffer_bytes - offset;
3750 for (src_seg=0; src_seg < st_bp->frp_segs; src_seg++) {
3751 src_offset = offset;
3752 if (src_offset < st_bp->frp[src_seg].length)
3753 break;
3754 offset -= st_bp->frp[src_seg].length;
3755 }
3756
3757 st_bp->buffer_bytes = st_bp->read_pointer = total;
3758 for (dst_seg=dst_offset=0; total > 0; ) {
3759 count = min(st_bp->frp[dst_seg].length - dst_offset,
3760 st_bp->frp[src_seg].length - src_offset);
3761 memmove(page_address(st_bp->frp[dst_seg].page) + dst_offset,
3762 page_address(st_bp->frp[src_seg].page) + src_offset, count);
3763 src_offset += count;
3764 if (src_offset >= st_bp->frp[src_seg].length) {
3765 src_seg++;
3766 src_offset = 0;
3767 }
3768 dst_offset += count;
3769 if (dst_offset >= st_bp->frp[dst_seg].length) {
3770 dst_seg++;
3771 dst_offset = 0;
3772 }
3773 total -= count;
3774 }
3775}
3776
3777
3778/* Fill the s/g list up to the length required for this transfer */
3779static void buf_to_sg(struct st_buffer *STbp, unsigned int length)
3780{
3781 int i;
3782 unsigned int count;
3783 struct scatterlist *sg;
3784 struct st_buf_fragment *frp;
3785
3786 if (length == STbp->frp_sg_current)
3787 return; /* work already done */
3788
3789 sg = &(STbp->sg[0]);
3790 frp = STbp->frp;
3791 for (i=count=0; count < length; i++) {
3792 sg[i].page = frp[i].page;
3793 if (length - count > frp[i].length)
3794 sg[i].length = frp[i].length;
3795 else
3796 sg[i].length = length - count;
3797 count += sg[i].length;
3798 sg[i].offset = 0;
3799 }
3800 STbp->sg_segs = i;
3801 STbp->frp_sg_current = length;
3802}
3803
3804
3805/* Validate the options from command line or module parameters */
3806static void validate_options(void)
3807{
3808 if (buffer_kbs > 0)
3809 st_fixed_buffer_size = buffer_kbs * ST_KILOBYTE;
3810 if (max_sg_segs >= ST_FIRST_SG)
3811 st_max_sg_segs = max_sg_segs;
3812}
3813
3814#ifndef MODULE
3815/* Set the boot options. Syntax is defined in Documenation/scsi/st.txt.
3816 */
3817static int __init st_setup(char *str)
3818{
3819 int i, len, ints[5];
3820 char *stp;
3821
3822 stp = get_options(str, ARRAY_SIZE(ints), ints);
3823
3824 if (ints[0] > 0) {
3825 for (i = 0; i < ints[0] && i < ARRAY_SIZE(parms); i++)
3826 if (parms[i].val)
3827 *parms[i].val = ints[i + 1];
3828 } else {
3829 while (stp != NULL) {
3830 for (i = 0; i < ARRAY_SIZE(parms); i++) {
3831 len = strlen(parms[i].name);
3832 if (!strncmp(stp, parms[i].name, len) &&
3833 (*(stp + len) == ':' || *(stp + len) == '=')) {
3834 if (parms[i].val)
3835 *parms[i].val =
3836 simple_strtoul(stp + len + 1, NULL, 0);
3837 else
3838 printk(KERN_WARNING "st: Obsolete parameter %s\n",
3839 parms[i].name);
3840 break;
3841 }
3842 }
6391a113 3843 if (i >= ARRAY_SIZE(parms))
1da177e4
LT		 3844 printk(KERN_WARNING "st: invalid parameter in '%s'\n",
3845 stp);
3846 stp = strchr(stp, ',');
3847 if (stp)
3848 stp++;
3849 }
3850 }
3851
3852 validate_options();
3853
3854 return 1;
3855}
3856
3857__setup("st=", st_setup);
3858
3859#endif
3860
3861static struct file_operations st_fops =
3862{
3863 .owner = THIS_MODULE,
3864 .read = st_read,
3865 .write = st_write,
3866 .ioctl = st_ioctl,
3867#ifdef CONFIG_COMPAT
3868 .compat_ioctl = st_compat_ioctl,
3869#endif
3870 .open = st_open,
3871 .flush = st_flush,
3872 .release = st_release,
3873};
3874
3875static int st_probe(struct device *dev)
3876{
3877 struct scsi_device *SDp = to_scsi_device(dev);
3878 struct gendisk *disk = NULL;
3879 struct cdev *cdev = NULL;
3880 struct scsi_tape *tpnt = NULL;
3881 struct st_modedef *STm;
3882 struct st_partstat *STps;
3883 struct st_buffer *buffer;
3884 int i, j, mode, dev_num, error;
3885 char *stp;
1da177e4
LT		 3886
3887 if (SDp->type != TYPE_TAPE)
3888 return -ENODEV;
3889 if ((stp = st_incompatible(SDp))) {
3bf743e7 3890 sdev_printk(KERN_INFO, SDp, "Found incompatible tape\n");
1da177e4
LT		 3891 printk(KERN_INFO "st: The suggested driver is %s.\n", stp);
3892 return -ENODEV;
3893 }
3894
8b05b773
MC		 3895 i = min(SDp->request_queue->max_hw_segments,
3896 SDp->request_queue->max_phys_segments);
1da177e4
LT		 3897 if (st_max_sg_segs < i)
3898 i = st_max_sg_segs;
3899 buffer = new_tape_buffer(1, (SDp->host)->unchecked_isa_dma, i);
3900 if (buffer == NULL) {
3901 printk(KERN_ERR
3902 "st: Can't allocate new tape buffer. Device not attached.\n");
3903 goto out;
3904 }
3905
3906 disk = alloc_disk(1);
3907 if (!disk) {
3908 printk(KERN_ERR "st: out of memory. Device not attached.\n");
3909 goto out_buffer_free;
3910 }
3911
3912 write_lock(&st_dev_arr_lock);
3913 if (st_nr_dev >= st_dev_max) {
3914 struct scsi_tape **tmp_da;
3915 int tmp_dev_max;
3916
3917 tmp_dev_max = max(st_nr_dev * 2, 8);
3918 if (tmp_dev_max > ST_MAX_TAPES)
3919 tmp_dev_max = ST_MAX_TAPES;
3920 if (tmp_dev_max <= st_nr_dev) {
3921 write_unlock(&st_dev_arr_lock);
3922 printk(KERN_ERR "st: Too many tape devices (max. %d).\n",
3923 ST_MAX_TAPES);
3924 goto out_put_disk;
3925 }
3926
24669f75 3927 tmp_da = kzalloc(tmp_dev_max * sizeof(struct scsi_tape *), GFP_ATOMIC);
1da177e4
LT		 3928 if (tmp_da == NULL) {
3929 write_unlock(&st_dev_arr_lock);
3930 printk(KERN_ERR "st: Can't extend device array.\n");
3931 goto out_put_disk;
3932 }
3933
1da177e4
LT		 3934 if (scsi_tapes != NULL) {
3935 memcpy(tmp_da, scsi_tapes,
3936 st_dev_max * sizeof(struct scsi_tape *));
3937 kfree(scsi_tapes);
3938 }
3939 scsi_tapes = tmp_da;
3940
3941 st_dev_max = tmp_dev_max;
3942 }
3943
3944 for (i = 0; i < st_dev_max; i++)
3945 if (scsi_tapes[i] == NULL)
3946 break;
3947 if (i >= st_dev_max)
3948 panic("scsi_devices corrupt (st)");
3949
24669f75 3950 tpnt = kzalloc(sizeof(struct scsi_tape), GFP_ATOMIC);
1da177e4
LT		 3951 if (tpnt == NULL) {
3952 write_unlock(&st_dev_arr_lock);
3953 printk(KERN_ERR "st: Can't allocate device descriptor.\n");
3954 goto out_put_disk;
3955 }
f03a5670 3956 kref_init(&tpnt->kref);
1da177e4
LT		 3957 tpnt->disk = disk;
3958 sprintf(disk->disk_name, "st%d", i);
3959 disk->private_data = &tpnt->driver;
3960 disk->queue = SDp->request_queue;
3961 tpnt->driver = &st_template;
3962 scsi_tapes[i] = tpnt;
3963 dev_num = i;
3964
3965 tpnt->device = SDp;
3966 if (SDp->scsi_level <= 2)
3967 tpnt->tape_type = MT_ISSCSI1;
3968 else
3969 tpnt->tape_type = MT_ISSCSI2;
3970
3971 tpnt->buffer = buffer;
f03a5670 3972 tpnt->buffer->last_SRpnt = NULL;
1da177e4
LT		 3973
3974 tpnt->inited = 0;
3975 tpnt->dirty = 0;
3976 tpnt->in_use = 0;
3977 tpnt->drv_buffer = 1; /* Try buffering if no mode sense */
3978 tpnt->restr_dma = (SDp->host)->unchecked_isa_dma;
3979 tpnt->use_pf = (SDp->scsi_level >= SCSI_2);
3980 tpnt->density = 0;
3981 tpnt->do_auto_lock = ST_AUTO_LOCK;
3982 tpnt->can_bsr = (SDp->scsi_level > 2 ? 1 : ST_IN_FILE_POS); /* BSR mandatory in SCSI3 */
3983 tpnt->can_partitions = 0;
3984 tpnt->two_fm = ST_TWO_FM;
3985 tpnt->fast_mteom = ST_FAST_MTEOM;
3986 tpnt->scsi2_logical = ST_SCSI2LOGICAL;
3987 tpnt->immediate = ST_NOWAIT;
3988 tpnt->default_drvbuffer = 0xff; /* No forced buffering */
3989 tpnt->partition = 0;
3990 tpnt->new_partition = 0;
3991 tpnt->nbr_partitions = 0;
3992 tpnt->device->timeout = ST_TIMEOUT;
3993 tpnt->long_timeout = ST_LONG_TIMEOUT;
3994 tpnt->try_dio = try_direct_io && !SDp->host->unchecked_isa_dma;
3995
1da177e4
LT		 3996 for (i = 0; i < ST_NBR_MODES; i++) {
3997 STm = &(tpnt->modes[i]);
3998 STm->defined = 0;
3999 STm->sysv = ST_SYSV;
4000 STm->defaults_for_writes = 0;
4001 STm->do_async_writes = ST_ASYNC_WRITES;
4002 STm->do_buffer_writes = ST_BUFFER_WRITES;
4003 STm->do_read_ahead = ST_READ_AHEAD;
4004 STm->default_compression = ST_DONT_TOUCH;
4005 STm->default_blksize = (-1); /* No forced size */
4006 STm->default_density = (-1); /* No forced density */
4007 }
4008
4009 for (i = 0; i < ST_NBR_PARTITIONS; i++) {
4010 STps = &(tpnt->ps[i]);
4011 STps->rw = ST_IDLE;
4012 STps->eof = ST_NOEOF;
4013 STps->at_sm = 0;
4014 STps->last_block_valid = 0;
4015 STps->drv_block = (-1);
4016 STps->drv_file = (-1);
4017 }
4018
4019 tpnt->current_mode = 0;
4020 tpnt->modes[0].defined = 1;
4021
4022 tpnt->density_changed = tpnt->compression_changed =
4023 tpnt->blksize_changed = 0;
4024 init_MUTEX(&tpnt->lock);
4025
4026 st_nr_dev++;
4027 write_unlock(&st_dev_arr_lock);
4028
4029 for (mode = 0; mode < ST_NBR_MODES; ++mode) {
4030 STm = &(tpnt->modes[mode]);
4031 for (j=0; j < 2; j++) {
4032 cdev = cdev_alloc();
4033 if (!cdev) {
4034 printk(KERN_ERR
4035 "st%d: out of memory. Device not attached.\n",
4036 dev_num);
4037 goto out_free_tape;
4038 }
4039 cdev->owner = THIS_MODULE;
4040 cdev->ops = &st_fops;
4041
4042 error = cdev_add(cdev,
4043 MKDEV(SCSI_TAPE_MAJOR, TAPE_MINOR(dev_num, mode, j)),
4044 1);
4045 if (error) {
4046 printk(KERN_ERR "st%d: Can't add %s-rewind mode %d\n",
4047 dev_num, j ? "non" : "auto", mode);
4048 printk(KERN_ERR "st%d: Device not attached.\n", dev_num);
4049 goto out_free_tape;
4050 }
4051 STm->cdevs[j] = cdev;
4052
4053 }
13026a6b
JG		 4054 error = do_create_class_files(tpnt, dev_num, mode);
4055 if (error)
4056 goto out_free_tape;
1da177e4
LT		 4057 }
4058
42252854 4059 sdev_printk(KERN_NOTICE, SDp,
8b1ea24c 4060 "Attached scsi tape %s\n", tape_name(tpnt));
42252854
KM		 4061 sdev_printk(KERN_INFO, SDp, "%s: try direct i/o: %s (alignment %d B)\n",
4062 tape_name(tpnt), tpnt->try_dio ? "yes" : "no",
4063 queue_dma_alignment(SDp->request_queue) + 1);
1da177e4
LT		 4064
4065 return 0;
4066
4067out_free_tape:
4068 for (mode=0; mode < ST_NBR_MODES; mode++) {
4069 STm = &(tpnt->modes[mode]);
4070 sysfs_remove_link(&tpnt->device->sdev_gendev.kobj,
4071 "tape");
4072 for (j=0; j < 2; j++) {
4073 if (STm->cdevs[j]) {
4074 if (cdev == STm->cdevs[j])
4075 cdev = NULL;
d253878b 4076 class_device_destroy(st_sysfs_class,
4077 MKDEV(SCSI_TAPE_MAJOR,
4078 TAPE_MINOR(i, mode, j)));
1da177e4
LT		 4079 cdev_del(STm->cdevs[j]);
4080 }
4081 }
4082 }
4083 if (cdev)
4084 cdev_del(cdev);
4085 write_lock(&st_dev_arr_lock);
4086 scsi_tapes[dev_num] = NULL;
4087 st_nr_dev--;
4088 write_unlock(&st_dev_arr_lock);
4089out_put_disk:
4090 put_disk(disk);
c9475cb0 4091 kfree(tpnt);
1da177e4
LT		 4092out_buffer_free:
4093 kfree(buffer);
4094out:
4095 return -ENODEV;
4096};
4097
4098
4099static int st_remove(struct device *dev)
4100{
4101 struct scsi_device *SDp = to_scsi_device(dev);
4102 struct scsi_tape *tpnt;
4103 int i, j, mode;
4104
4105 write_lock(&st_dev_arr_lock);
4106 for (i = 0; i < st_dev_max; i++) {
4107 tpnt = scsi_tapes[i];
4108 if (tpnt != NULL && tpnt->device == SDp) {
4109 scsi_tapes[i] = NULL;
4110 st_nr_dev--;
4111 write_unlock(&st_dev_arr_lock);
1da177e4
LT		 4112 sysfs_remove_link(&tpnt->device->sdev_gendev.kobj,
4113 "tape");
4114 for (mode = 0; mode < ST_NBR_MODES; ++mode) {
1da177e4 4115 for (j=0; j < 2; j++) {
d253878b 4116 class_device_destroy(st_sysfs_class,
4117 MKDEV(SCSI_TAPE_MAJOR,
4118 TAPE_MINOR(i, mode, j)));
1da177e4
LT		 4119 cdev_del(tpnt->modes[mode].cdevs[j]);
4120 tpnt->modes[mode].cdevs[j] = NULL;
4121 }
4122 }
1da177e4 4123
0b950672 4124 mutex_lock(&st_ref_mutex);
f03a5670 4125 kref_put(&tpnt->kref, scsi_tape_release);
0b950672 4126 mutex_unlock(&st_ref_mutex);
1da177e4
LT		 4127 return 0;
4128 }
4129 }
4130
4131 write_unlock(&st_dev_arr_lock);
4132 return 0;
4133}
4134
f03a5670
KM		 4135/**
4136 * scsi_tape_release - Called to free the Scsi_Tape structure
4137 * @kref: pointer to embedded kref
4138 *
0b950672 4139 * st_ref_mutex must be held entering this routine. Because it is
f03a5670
KM		 4140 * called on last put, you should always use the scsi_tape_get()
4141 * scsi_tape_put() helpers which manipulate the semaphore directly
4142 * and never do a direct kref_put().
4143 **/
4144static void scsi_tape_release(struct kref *kref)
4145{
4146 struct scsi_tape *tpnt = to_scsi_tape(kref);
4147 struct gendisk *disk = tpnt->disk;
4148
4149 tpnt->device = NULL;
4150
4151 if (tpnt->buffer) {
4152 tpnt->buffer->orig_frp_segs = 0;
4153 normalize_buffer(tpnt->buffer);
4154 kfree(tpnt->buffer);
4155 }
4156
4157 disk->private_data = NULL;
4158 put_disk(disk);
4159 kfree(tpnt);
4160 return;
4161}
4162
1da177e4
LT		 4163static int __init init_st(void)
4164{
13026a6b
JG		 4165 int err;
4166
1da177e4
LT		 4167 validate_options();
4168
13026a6b 4169 printk(KERN_INFO "st: Version %s, fixed bufsize %d, s/g segs %d\n",
1da177e4
LT		 4170 verstr, st_fixed_buffer_size, st_max_sg_segs);
4171
d253878b 4172 st_sysfs_class = class_create(THIS_MODULE, "scsi_tape");
1da177e4 4173 if (IS_ERR(st_sysfs_class)) {
1da177e4 4174 printk(KERN_ERR "Unable create sysfs class for SCSI tapes\n");
13026a6b 4175 return PTR_ERR(st_sysfs_class);
1da177e4
LT		 4176 }
4177
13026a6b
JG		 4178 err = register_chrdev_region(MKDEV(SCSI_TAPE_MAJOR, 0),
4179 ST_MAX_TAPE_ENTRIES, "st");
4180 if (err) {
4181 printk(KERN_ERR "Unable to get major %d for SCSI tapes\n",
4182 SCSI_TAPE_MAJOR);
4183 goto err_class;
1da177e4
LT		 4184 }
4185
13026a6b
JG		 4186 err = scsi_register_driver(&st_template.gendrv);
4187 if (err)
4188 goto err_chrdev;
4189
4190 err = do_create_driverfs_files();
4191 if (err)
4192 goto err_scsidrv;
4193
4194 return 0;
4195
4196err_scsidrv:
4197 scsi_unregister_driver(&st_template.gendrv);
4198err_chrdev:
4199 unregister_chrdev_region(MKDEV(SCSI_TAPE_MAJOR, 0),
4200 ST_MAX_TAPE_ENTRIES);
4201err_class:
4202 class_destroy(st_sysfs_class);
4203 return err;
1da177e4
LT		 4204}
4205
4206static void __exit exit_st(void)
4207{
1da177e4
LT		 4208 do_remove_driverfs_files();
4209 scsi_unregister_driver(&st_template.gendrv);
4210 unregister_chrdev_region(MKDEV(SCSI_TAPE_MAJOR, 0),
4211 ST_MAX_TAPE_ENTRIES);
c2c96f46 4212 class_destroy(st_sysfs_class);
1da177e4
LT		 4213 kfree(scsi_tapes);
4214 printk(KERN_INFO "st: Unloaded.\n");
4215}
4216
4217module_init(init_st);
4218module_exit(exit_st);
4219
4220
4221/* The sysfs driver interface. Read-only at the moment */
4222static ssize_t st_try_direct_io_show(struct device_driver *ddp, char *buf)
4223{
4224 return snprintf(buf, PAGE_SIZE, "%d\n", try_direct_io);
4225}
4226static DRIVER_ATTR(try_direct_io, S_IRUGO, st_try_direct_io_show, NULL);
4227
4228static ssize_t st_fixed_buffer_size_show(struct device_driver *ddp, char *buf)
4229{
4230 return snprintf(buf, PAGE_SIZE, "%d\n", st_fixed_buffer_size);
4231}
4232static DRIVER_ATTR(fixed_buffer_size, S_IRUGO, st_fixed_buffer_size_show, NULL);
4233
4234static ssize_t st_max_sg_segs_show(struct device_driver *ddp, char *buf)
4235{
4236 return snprintf(buf, PAGE_SIZE, "%d\n", st_max_sg_segs);
4237}
4238static DRIVER_ATTR(max_sg_segs, S_IRUGO, st_max_sg_segs_show, NULL);
4239
4240static ssize_t st_version_show(struct device_driver *ddd, char *buf)
4241{
4242 return snprintf(buf, PAGE_SIZE, "[%s]\n", verstr);
4243}
4244static DRIVER_ATTR(version, S_IRUGO, st_version_show, NULL);
4245
13026a6b 4246static int do_create_driverfs_files(void)
1da177e4
LT		 4247{
4248 struct device_driver *driverfs = &st_template.gendrv;
13026a6b
JG		 4249 int err;
4250
4251 err = driver_create_file(driverfs, &driver_attr_try_direct_io);
4252 if (err)
4253 return err;
4254 err = driver_create_file(driverfs, &driver_attr_fixed_buffer_size);
4255 if (err)
4256 goto err_try_direct_io;
4257 err = driver_create_file(driverfs, &driver_attr_max_sg_segs);
4258 if (err)
4259 goto err_attr_fixed_buf;
4260 err = driver_create_file(driverfs, &driver_attr_version);
4261 if (err)
4262 goto err_attr_max_sg;
1da177e4 4263
13026a6b
JG		 4264 return 0;
4265
4266err_attr_max_sg:
4267 driver_remove_file(driverfs, &driver_attr_max_sg_segs);
4268err_attr_fixed_buf:
4269 driver_remove_file(driverfs, &driver_attr_fixed_buffer_size);
4270err_try_direct_io:
4271 driver_remove_file(driverfs, &driver_attr_try_direct_io);
4272 return err;
1da177e4
LT		 4273}
4274
4275static void do_remove_driverfs_files(void)
4276{
4277 struct device_driver *driverfs = &st_template.gendrv;
4278
4279 driver_remove_file(driverfs, &driver_attr_version);
4280 driver_remove_file(driverfs, &driver_attr_max_sg_segs);
4281 driver_remove_file(driverfs, &driver_attr_fixed_buffer_size);
4282 driver_remove_file(driverfs, &driver_attr_try_direct_io);
4283}
4284
4285
4286/* The sysfs simple class interface */
4287static ssize_t st_defined_show(struct class_device *class_dev, char *buf)
4288{
4289 struct st_modedef *STm = (struct st_modedef *)class_get_devdata(class_dev);
4290 ssize_t l = 0;
4291
4292 l = snprintf(buf, PAGE_SIZE, "%d\n", STm->defined);
4293 return l;
4294}
4295
4296CLASS_DEVICE_ATTR(defined, S_IRUGO, st_defined_show, NULL);
4297
4298static ssize_t st_defblk_show(struct class_device *class_dev, char *buf)
4299{
4300 struct st_modedef *STm = (struct st_modedef *)class_get_devdata(class_dev);
4301 ssize_t l = 0;
4302
4303 l = snprintf(buf, PAGE_SIZE, "%d\n", STm->default_blksize);
4304 return l;
4305}
4306
4307CLASS_DEVICE_ATTR(default_blksize, S_IRUGO, st_defblk_show, NULL);
4308
4309static ssize_t st_defdensity_show(struct class_device *class_dev, char *buf)
4310{
4311 struct st_modedef *STm = (struct st_modedef *)class_get_devdata(class_dev);
4312 ssize_t l = 0;
4313 char *fmt;
4314
4315 fmt = STm->default_density >= 0 ? "0x%02x\n" : "%d\n";
4316 l = snprintf(buf, PAGE_SIZE, fmt, STm->default_density);
4317 return l;
4318}
4319
4320CLASS_DEVICE_ATTR(default_density, S_IRUGO, st_defdensity_show, NULL);
4321
4322static ssize_t st_defcompression_show(struct class_device *class_dev, char *buf)
4323{
4324 struct st_modedef *STm = (struct st_modedef *)class_get_devdata(class_dev);
4325 ssize_t l = 0;
4326
4327 l = snprintf(buf, PAGE_SIZE, "%d\n", STm->default_compression - 1);
4328 return l;
4329}
4330
4331CLASS_DEVICE_ATTR(default_compression, S_IRUGO, st_defcompression_show, NULL);
4332
13026a6b 4333static int do_create_class_files(struct scsi_tape *STp, int dev_num, int mode)
1da177e4
LT		 4334{
4335 int i, rew, error;
4336 char name[10];
4337 struct class_device *st_class_member;
4338
1da177e4
LT		 4339 for (rew=0; rew < 2; rew++) {
4340 /* Make sure that the minor numbers corresponding to the four
4341 first modes always get the same names */
4342 i = mode << (4 - ST_NBR_MODE_BITS);
4343 snprintf(name, 10, "%s%s%s", rew ? "n" : "",
4344 STp->disk->disk_name, st_formats[i]);
4345 st_class_member =
53f46542 4346 class_device_create(st_sysfs_class, NULL,
d253878b 4347 MKDEV(SCSI_TAPE_MAJOR,
4348 TAPE_MINOR(dev_num, mode, rew)),
4349 &STp->device->sdev_gendev, "%s", name);
1da177e4 4350 if (IS_ERR(st_class_member)) {
d253878b 4351 printk(KERN_WARNING "st%d: class_device_create failed\n",
1da177e4 4352 dev_num);
13026a6b 4353 error = PTR_ERR(st_class_member);
1da177e4
LT		 4354 goto out;
4355 }
4356 class_set_devdata(st_class_member, &STp->modes[mode]);
4357
13026a6b
JG		 4358 error = class_device_create_file(st_class_member,
4359 &class_device_attr_defined);
4360 if (error) goto out;
4361 error = class_device_create_file(st_class_member,
4362 &class_device_attr_default_blksize);
4363 if (error) goto out;
4364 error = class_device_create_file(st_class_member,
4365 &class_device_attr_default_density);
4366 if (error) goto out;
4367 error = class_device_create_file(st_class_member,
4368 &class_device_attr_default_compression);
4369 if (error) goto out;
4370
1da177e4
LT		 4371 if (mode == 0 && rew == 0) {
4372 error = sysfs_create_link(&STp->device->sdev_gendev.kobj,
4373 &st_class_member->kobj,
4374 "tape");
4375 if (error) {
4376 printk(KERN_ERR
4377 "st%d: Can't create sysfs link from SCSI device.\n",
4378 dev_num);
13026a6b 4379 goto out;
1da177e4
LT		 4380 }
4381 }
4382 }
13026a6b
JG		 4383
4384 return 0;
4385
4386out:
4387 return error;
1da177e4
LT		 4388}
4389
1da177e4
LT		 4390/* The following functions may be useful for a larger audience. */
4391static int sgl_map_user_pages(struct scatterlist *sgl, const unsigned int max_pages,
4392 unsigned long uaddr, size_t count, int rw)
4393{
07542b83
JB		 4394 unsigned long end = (uaddr + count + PAGE_SIZE - 1) >> PAGE_SHIFT;
4395 unsigned long start = uaddr >> PAGE_SHIFT;
4396 const int nr_pages = end - start;
1da177e4 4397 int res, i, j;
1da177e4
LT		 4398 struct page **pages;
4399
1da177e4
LT		 4400 /* User attempted Overflow! */
4401 if ((uaddr + count) < uaddr)
4402 return -EINVAL;
4403
4404 /* Too big */
4405 if (nr_pages > max_pages)
4406 return -ENOMEM;
4407
4408 /* Hmm? */
4409 if (count == 0)
4410 return 0;
4411
4412 if ((pages = kmalloc(max_pages * sizeof(*pages), GFP_KERNEL)) == NULL)
4413 return -ENOMEM;
4414
4415 /* Try to fault in all of the necessary pages */
4416 down_read(&current->mm->mmap_sem);
4417 /* rw==READ means read from drive, write into memory area */
4418 res = get_user_pages(
4419 current,
4420 current->mm,
4421 uaddr,
4422 nr_pages,
4423 rw == READ,
4424 0, /* don't force */
4425 pages,
4426 NULL);
4427 up_read(&current->mm->mmap_sem);
4428
4429 /* Errors and no page mapped should return here */
4430 if (res < nr_pages)
4431 goto out_unmap;
4432
4433 for (i=0; i < nr_pages; i++) {
4434 /* FIXME: flush superflous for rw==READ,
4435 * probably wrong function for rw==WRITE
4436 */
4437 flush_dcache_page(pages[i]);
4438 }
4439
4440 /* Populate the scatter/gather list */
4441 sgl[0].page = pages[0];
4442 sgl[0].offset = uaddr & ~PAGE_MASK;
4443 if (nr_pages > 1) {
4444 sgl[0].length = PAGE_SIZE - sgl[0].offset;
4445 count -= sgl[0].length;
4446 for (i=1; i < nr_pages ; i++) {
4447 sgl[i].offset = 0;
4448 sgl[i].page = pages[i];
4449 sgl[i].length = count < PAGE_SIZE ? count : PAGE_SIZE;
4450 count -= PAGE_SIZE;
4451 }
4452 }
4453 else {
4454 sgl[0].length = count;
4455 }
4456
4457 kfree(pages);
4458 return nr_pages;
4459
4460 out_unmap:
4461 if (res > 0) {
4462 for (j=0; j < res; j++)
4463 page_cache_release(pages[j]);
6bc733e9 4464 res = 0;
1da177e4
LT		 4465 }
4466 kfree(pages);
4467 return res;
4468}
4469
4470
4471/* And unmap them... */
4472static int sgl_unmap_user_pages(struct scatterlist *sgl, const unsigned int nr_pages,
4473 int dirtied)
4474{
4475 int i;
4476
4477 for (i=0; i < nr_pages; i++) {
b5810039
NP		 4478 struct page *page = sgl[i].page;
4479
b5810039
NP		 4480 if (dirtied)
4481 SetPageDirty(page);
1da177e4
LT		 4482 /* FIXME: cache flush missing for rw==READ
4483 * FIXME: call the correct reference counting function
4484 */
b5810039 4485 page_cache_release(page);
1da177e4
LT		 4486 }
4487
4488 return 0;
4489}
Linux 6.x block layer and io_uring tree(s)