osst.c revision 25985edcedea6396277003854657b5f3cb31a628
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
7  OnStream SCSI Tape support (osst) cloned from st.c by
8  Willem Riede (osst@riede.org) Feb 2000
9  Fixes ... Kurt Garloff <garloff@suse.de> Mar 2000
10
11  Rewritten from Dwayne Forsyth's SCSI tape driver by Kai Makisara.
12  Contribution and ideas from several people including (in alphabetical
13  order) Klaus Ehrenfried, Wolfgang Denk, Steve Hirsch, Andreas Koppenh"ofer,
14  Michael Leodolter, Eyal Lebedinsky, J"org Weule, and Eric Youngdale.
15
16  Copyright 1992 - 2002 Kai Makisara / 2000 - 2006 Willem Riede
17	 email osst@riede.org
18
19  $Header: /cvsroot/osst/Driver/osst.c,v 1.73 2005/01/01 21:13:34 wriede Exp $
20
21  Microscopic alterations - Rik Ling, 2000/12/21
22  Last st.c sync: Tue Oct 15 22:01:04 2002 by makisara
23  Some small formal changes - aeb, 950809
24*/
25
26static const char * cvsid = "$Id: osst.c,v 1.73 2005/01/01 21:13:34 wriede Exp $";
27static const char * osst_version = "0.99.4";
28
29/* The "failure to reconnect" firmware bug */
30#define OSST_FW_NEED_POLL_MIN 10601 /*(107A)*/
31#define OSST_FW_NEED_POLL_MAX 10704 /*(108D)*/
32#define OSST_FW_NEED_POLL(x,d) ((x) >= OSST_FW_NEED_POLL_MIN && (x) <= OSST_FW_NEED_POLL_MAX && d->host->this_id != 7)
33
34#include <linux/module.h>
35
36#include <linux/fs.h>
37#include <linux/kernel.h>
38#include <linux/sched.h>
39#include <linux/proc_fs.h>
40#include <linux/mm.h>
41#include <linux/slab.h>
42#include <linux/init.h>
43#include <linux/string.h>
44#include <linux/errno.h>
45#include <linux/mtio.h>
46#include <linux/ioctl.h>
47#include <linux/fcntl.h>
48#include <linux/spinlock.h>
49#include <linux/vmalloc.h>
50#include <linux/blkdev.h>
51#include <linux/moduleparam.h>
52#include <linux/delay.h>
53#include <linux/jiffies.h>
54#include <linux/mutex.h>
55#include <asm/uaccess.h>
56#include <asm/dma.h>
57#include <asm/system.h>
58
59/* The driver prints some debugging information on the console if DEBUG
60   is defined and non-zero. */
61#define DEBUG 0
62
63/* The message level for the debug messages is currently set to KERN_NOTICE
64   so that people can easily see the messages. Later when the debugging messages
65   in the drivers are more widely classified, this may be changed to KERN_DEBUG. */
66#define OSST_DEB_MSG  KERN_NOTICE
67
68#include <scsi/scsi.h>
69#include <scsi/scsi_dbg.h>
70#include <scsi/scsi_device.h>
71#include <scsi/scsi_driver.h>
72#include <scsi/scsi_eh.h>
73#include <scsi/scsi_host.h>
74#include <scsi/scsi_ioctl.h>
75
76#define ST_KILOBYTE 1024
77
78#include "st.h"
79#include "osst.h"
80#include "osst_options.h"
81#include "osst_detect.h"
82
83static DEFINE_MUTEX(osst_int_mutex);
84static int max_dev = 0;
85static int write_threshold_kbs = 0;
86static int max_sg_segs = 0;
87
88#ifdef MODULE
89MODULE_AUTHOR("Willem Riede");
90MODULE_DESCRIPTION("OnStream {DI-|FW-|SC-|USB}{30|50} Tape Driver");
91MODULE_LICENSE("GPL");
92MODULE_ALIAS_CHARDEV_MAJOR(OSST_MAJOR);
93MODULE_ALIAS_SCSI_DEVICE(TYPE_TAPE);
94
95module_param(max_dev, int, 0444);
96MODULE_PARM_DESC(max_dev, "Maximum number of OnStream Tape Drives to attach (4)");
97
98module_param(write_threshold_kbs, int, 0644);
99MODULE_PARM_DESC(write_threshold_kbs, "Asynchronous write threshold (KB; 32)");
100
101module_param(max_sg_segs, int, 0644);
102MODULE_PARM_DESC(max_sg_segs, "Maximum number of scatter/gather segments to use (9)");
103#else
104static struct osst_dev_parm {
105       char   *name;
106       int    *val;
107} parms[] __initdata = {
108       { "max_dev",             &max_dev             },
109       { "write_threshold_kbs", &write_threshold_kbs },
110       { "max_sg_segs",         &max_sg_segs         }
111};
112#endif
113
114/* Some default definitions have been moved to osst_options.h */
115#define OSST_BUFFER_SIZE (OSST_BUFFER_BLOCKS * ST_KILOBYTE)
116#define OSST_WRITE_THRESHOLD (OSST_WRITE_THRESHOLD_BLOCKS * ST_KILOBYTE)
117
118/* The buffer size should fit into the 24 bits for length in the
119   6-byte SCSI read and write commands. */
120#if OSST_BUFFER_SIZE >= (2 << 24 - 1)
121#error "Buffer size should not exceed (2 << 24 - 1) bytes!"
122#endif
123
124#if DEBUG
125static int debugging = 1;
126/* uncomment define below to test error recovery */
127// #define OSST_INJECT_ERRORS 1
128#endif
129
130/* Do not retry! The drive firmware already retries when appropriate,
131   and when it tries to tell us something, we had better listen... */
132#define MAX_RETRIES 0
133
134#define NO_TAPE  NOT_READY
135
136#define OSST_WAIT_POSITION_COMPLETE   (HZ > 200 ? HZ / 200 : 1)
137#define OSST_WAIT_WRITE_COMPLETE      (HZ / 12)
138#define OSST_WAIT_LONG_WRITE_COMPLETE (HZ / 2)
139
140#define OSST_TIMEOUT (200 * HZ)
141#define OSST_LONG_TIMEOUT (1800 * HZ)
142
143#define TAPE_NR(x) (iminor(x) & ~(-1 << ST_MODE_SHIFT))
144#define TAPE_MODE(x) ((iminor(x) & ST_MODE_MASK) >> ST_MODE_SHIFT)
145#define TAPE_REWIND(x) ((iminor(x) & 0x80) == 0)
146#define TAPE_IS_RAW(x) (TAPE_MODE(x) & (ST_NBR_MODES >> 1))
147
148/* Internal ioctl to set both density (uppermost 8 bits) and blocksize (lower
149   24 bits) */
150#define SET_DENS_AND_BLK 0x10001
151
152static int osst_buffer_size       = OSST_BUFFER_SIZE;
153static int osst_write_threshold   = OSST_WRITE_THRESHOLD;
154static int osst_max_sg_segs       = OSST_MAX_SG;
155static int osst_max_dev           = OSST_MAX_TAPES;
156static int osst_nr_dev;
157
158static struct osst_tape **os_scsi_tapes = NULL;
159static DEFINE_RWLOCK(os_scsi_tapes_lock);
160
161static int modes_defined = 0;
162
163static struct osst_buffer *new_tape_buffer(int, int, int);
164static int enlarge_buffer(struct osst_buffer *, int);
165static void normalize_buffer(struct osst_buffer *);
166static int append_to_buffer(const char __user *, struct osst_buffer *, int);
167static int from_buffer(struct osst_buffer *, char __user *, int);
168static int osst_zero_buffer_tail(struct osst_buffer *);
169static int osst_copy_to_buffer(struct osst_buffer *, unsigned char *);
170static int osst_copy_from_buffer(struct osst_buffer *, unsigned char *);
171
172static int osst_probe(struct device *);
173static int osst_remove(struct device *);
174
175static struct scsi_driver osst_template = {
176	.owner			= THIS_MODULE,
177	.gendrv = {
178		.name		=  "osst",
179		.probe		= osst_probe,
180		.remove		= osst_remove,
181	}
182};
183
184static int osst_int_ioctl(struct osst_tape *STp, struct osst_request ** aSRpnt,
185			    unsigned int cmd_in, unsigned long arg);
186
187static int osst_set_frame_position(struct osst_tape *STp, struct osst_request ** aSRpnt, int frame, int skip);
188
189static int osst_get_frame_position(struct osst_tape *STp, struct osst_request ** aSRpnt);
190
191static int osst_flush_write_buffer(struct osst_tape *STp, struct osst_request ** aSRpnt);
192
193static int osst_write_error_recovery(struct osst_tape * STp, struct osst_request ** aSRpnt, int pending);
194
195static inline char *tape_name(struct osst_tape *tape)
196{
197	return tape->drive->disk_name;
198}
199
200/* Routines that handle the interaction with mid-layer SCSI routines */
201
202
203/* Normalize Sense */
204static void osst_analyze_sense(struct osst_request *SRpnt, struct st_cmdstatus *s)
205{
206	const u8 *ucp;
207	const u8 *sense = SRpnt->sense;
208
209	s->have_sense = scsi_normalize_sense(SRpnt->sense,
210				SCSI_SENSE_BUFFERSIZE, &s->sense_hdr);
211	s->flags = 0;
212
213	if (s->have_sense) {
214		s->deferred = 0;
215		s->remainder_valid =
216			scsi_get_sense_info_fld(sense, SCSI_SENSE_BUFFERSIZE, &s->uremainder64);
217		switch (sense[0] & 0x7f) {
218		case 0x71:
219			s->deferred = 1;
220		case 0x70:
221			s->fixed_format = 1;
222			s->flags = sense[2] & 0xe0;
223			break;
224		case 0x73:
225			s->deferred = 1;
226		case 0x72:
227			s->fixed_format = 0;
228			ucp = scsi_sense_desc_find(sense, SCSI_SENSE_BUFFERSIZE, 4);
229			s->flags = ucp ? (ucp[3] & 0xe0) : 0;
230			break;
231		}
232	}
233}
234
235/* Convert the result to success code */
236static int osst_chk_result(struct osst_tape * STp, struct osst_request * SRpnt)
237{
238	char *name = tape_name(STp);
239	int result = SRpnt->result;
240	u8 * sense = SRpnt->sense, scode;
241#if DEBUG
242	const char *stp;
243#endif
244	struct st_cmdstatus *cmdstatp;
245
246	if (!result)
247		return 0;
248
249	cmdstatp = &STp->buffer->cmdstat;
250	osst_analyze_sense(SRpnt, cmdstatp);
251
252	if (cmdstatp->have_sense)
253		scode = STp->buffer->cmdstat.sense_hdr.sense_key;
254	else
255		scode = 0;
256#if DEBUG
257	if (debugging) {
258		printk(OSST_DEB_MSG "%s:D: Error: %x, cmd: %x %x %x %x %x %x\n",
259		   name, result,
260		   SRpnt->cmd[0], SRpnt->cmd[1], SRpnt->cmd[2],
261		   SRpnt->cmd[3], SRpnt->cmd[4], SRpnt->cmd[5]);
262		if (scode) printk(OSST_DEB_MSG "%s:D: Sense: %02x, ASC: %02x, ASCQ: %02x\n",
263			       	name, scode, sense[12], sense[13]);
264		if (cmdstatp->have_sense)
265			__scsi_print_sense("osst ", SRpnt->sense, SCSI_SENSE_BUFFERSIZE);
266	}
267	else
268#endif
269	if (cmdstatp->have_sense && (
270		 scode != NO_SENSE &&
271		 scode != RECOVERED_ERROR &&
272/*      	 scode != UNIT_ATTENTION && */
273		 scode != BLANK_CHECK &&
274		 scode != VOLUME_OVERFLOW &&
275		 SRpnt->cmd[0] != MODE_SENSE &&
276		 SRpnt->cmd[0] != TEST_UNIT_READY)) { /* Abnormal conditions for tape */
277		if (cmdstatp->have_sense) {
278			printk(KERN_WARNING "%s:W: Command with sense data:\n", name);
279			__scsi_print_sense("osst ", SRpnt->sense, SCSI_SENSE_BUFFERSIZE);
280		}
281		else {
282			static	int	notyetprinted = 1;
283
284			printk(KERN_WARNING
285			     "%s:W: Warning %x (driver bt 0x%x, host bt 0x%x).\n",
286			     name, result, driver_byte(result),
287			     host_byte(result));
288			if (notyetprinted) {
289				notyetprinted = 0;
290				printk(KERN_INFO
291					"%s:I: This warning may be caused by your scsi controller,\n", name);
292				printk(KERN_INFO
293					"%s:I: it has been reported with some Buslogic cards.\n", name);
294			}
295		}
296	}
297	STp->pos_unknown |= STp->device->was_reset;
298
299	if (cmdstatp->have_sense && scode == RECOVERED_ERROR) {
300		STp->recover_count++;
301		STp->recover_erreg++;
302#if DEBUG
303		if (debugging) {
304			if (SRpnt->cmd[0] == READ_6)
305				stp = "read";
306			else if (SRpnt->cmd[0] == WRITE_6)
307				stp = "write";
308			else
309				stp = "ioctl";
310			printk(OSST_DEB_MSG "%s:D: Recovered %s error (%d).\n", name, stp,
311					     STp->recover_count);
312		}
313#endif
314		if ((sense[2] & 0xe0) == 0)
315			return 0;
316	}
317	return (-EIO);
318}
319
320
321/* Wakeup from interrupt */
322static void osst_end_async(struct request *req, int update)
323{
324	struct osst_request *SRpnt = req->end_io_data;
325	struct osst_tape *STp = SRpnt->stp;
326	struct rq_map_data *mdata = &SRpnt->stp->buffer->map_data;
327
328	STp->buffer->cmdstat.midlevel_result = SRpnt->result = req->errors;
329#if DEBUG
330	STp->write_pending = 0;
331#endif
332	if (SRpnt->waiting)
333		complete(SRpnt->waiting);
334
335	if (SRpnt->bio) {
336		kfree(mdata->pages);
337		blk_rq_unmap_user(SRpnt->bio);
338	}
339
340	__blk_put_request(req->q, req);
341}
342
343/* osst_request memory management */
344static struct osst_request *osst_allocate_request(void)
345{
346	return kzalloc(sizeof(struct osst_request), GFP_KERNEL);
347}
348
349static void osst_release_request(struct osst_request *streq)
350{
351	kfree(streq);
352}
353
354static int osst_execute(struct osst_request *SRpnt, const unsigned char *cmd,
355			int cmd_len, int data_direction, void *buffer, unsigned bufflen,
356			int use_sg, int timeout, int retries)
357{
358	struct request *req;
359	struct page **pages = NULL;
360	struct rq_map_data *mdata = &SRpnt->stp->buffer->map_data;
361
362	int err = 0;
363	int write = (data_direction == DMA_TO_DEVICE);
364
365	req = blk_get_request(SRpnt->stp->device->request_queue, write, GFP_KERNEL);
366	if (!req)
367		return DRIVER_ERROR << 24;
368
369	req->cmd_type = REQ_TYPE_BLOCK_PC;
370	req->cmd_flags |= REQ_QUIET;
371
372	SRpnt->bio = NULL;
373
374	if (use_sg) {
375		struct scatterlist *sg, *sgl = (struct scatterlist *)buffer;
376		int i;
377
378		pages = kzalloc(use_sg * sizeof(struct page *), GFP_KERNEL);
379		if (!pages)
380			goto free_req;
381
382		for_each_sg(sgl, sg, use_sg, i)
383			pages[i] = sg_page(sg);
384
385		mdata->null_mapped = 1;
386
387		mdata->page_order = get_order(sgl[0].length);
388		mdata->nr_entries =
389			DIV_ROUND_UP(bufflen, PAGE_SIZE << mdata->page_order);
390		mdata->offset = 0;
391
392		err = blk_rq_map_user(req->q, req, mdata, NULL, bufflen, GFP_KERNEL);
393		if (err) {
394			kfree(pages);
395			goto free_req;
396		}
397		SRpnt->bio = req->bio;
398		mdata->pages = pages;
399
400	} else if (bufflen) {
401		err = blk_rq_map_kern(req->q, req, buffer, bufflen, GFP_KERNEL);
402		if (err)
403			goto free_req;
404	}
405
406	req->cmd_len = cmd_len;
407	memset(req->cmd, 0, BLK_MAX_CDB); /* ATAPI hates garbage after CDB */
408	memcpy(req->cmd, cmd, req->cmd_len);
409	req->sense = SRpnt->sense;
410	req->sense_len = 0;
411	req->timeout = timeout;
412	req->retries = retries;
413	req->end_io_data = SRpnt;
414
415	blk_execute_rq_nowait(req->q, NULL, req, 1, osst_end_async);
416	return 0;
417free_req:
418	blk_put_request(req);
419	return DRIVER_ERROR << 24;
420}
421
422/* Do the scsi command. Waits until command performed if do_wait is true.
423   Otherwise osst_write_behind_check() is used to check that the command
424   has finished. */
425static	struct osst_request * osst_do_scsi(struct osst_request *SRpnt, struct osst_tape *STp,
426	unsigned char *cmd, int bytes, int direction, int timeout, int retries, int do_wait)
427{
428	unsigned char *bp;
429	unsigned short use_sg;
430#ifdef OSST_INJECT_ERRORS
431	static   int   inject = 0;
432	static   int   repeat = 0;
433#endif
434	struct completion *waiting;
435
436	/* if async, make sure there's no command outstanding */
437	if (!do_wait && ((STp->buffer)->last_SRpnt)) {
438		printk(KERN_ERR "%s: Async command already active.\n",
439		       tape_name(STp));
440		if (signal_pending(current))
441			(STp->buffer)->syscall_result = (-EINTR);
442		else
443			(STp->buffer)->syscall_result = (-EBUSY);
444		return NULL;
445	}
446
447	if (SRpnt == NULL) {
448		SRpnt = osst_allocate_request();
449		if (SRpnt == NULL) {
450			printk(KERN_ERR "%s: Can't allocate SCSI request.\n",
451				     tape_name(STp));
452			if (signal_pending(current))
453				(STp->buffer)->syscall_result = (-EINTR);
454			else
455				(STp->buffer)->syscall_result = (-EBUSY);
456			return NULL;
457		}
458		SRpnt->stp = STp;
459	}
460
461	/* If async IO, set last_SRpnt. This ptr tells write_behind_check
462	   which IO is outstanding. It's nulled out when the IO completes. */
463	if (!do_wait)
464		(STp->buffer)->last_SRpnt = SRpnt;
465
466	waiting = &STp->wait;
467	init_completion(waiting);
468	SRpnt->waiting = waiting;
469
470	use_sg = (bytes > STp->buffer->sg[0].length) ? STp->buffer->use_sg : 0;
471	if (use_sg) {
472		bp = (char *)&(STp->buffer->sg[0]);
473		if (STp->buffer->sg_segs < use_sg)
474			use_sg = STp->buffer->sg_segs;
475	}
476	else
477		bp = (STp->buffer)->b_data;
478
479	memcpy(SRpnt->cmd, cmd, sizeof(SRpnt->cmd));
480	STp->buffer->cmdstat.have_sense = 0;
481	STp->buffer->syscall_result = 0;
482
483	if (osst_execute(SRpnt, cmd, COMMAND_SIZE(cmd[0]), direction, bp, bytes,
484			 use_sg, timeout, retries))
485		/* could not allocate the buffer or request was too large */
486		(STp->buffer)->syscall_result = (-EBUSY);
487	else if (do_wait) {
488		wait_for_completion(waiting);
489		SRpnt->waiting = NULL;
490		STp->buffer->syscall_result = osst_chk_result(STp, SRpnt);
491#ifdef OSST_INJECT_ERRORS
492		if (STp->buffer->syscall_result == 0 &&
493		    cmd[0] == READ_6 &&
494		    cmd[4] &&
495		    ( (++ inject % 83) == 29  ||
496		      (STp->first_frame_position == 240
497			         /* or STp->read_error_frame to fail again on the block calculated above */ &&
498				 ++repeat < 3))) {
499			printk(OSST_DEB_MSG "%s:D: Injecting read error\n", tape_name(STp));
500			STp->buffer->last_result_fatal = 1;
501		}
502#endif
503	}
504	return SRpnt;
505}
506
507
508/* Handle the write-behind checking (downs the semaphore) */
509static void osst_write_behind_check(struct osst_tape *STp)
510{
511	struct osst_buffer * STbuffer;
512
513	STbuffer = STp->buffer;
514
515#if DEBUG
516	if (STp->write_pending)
517		STp->nbr_waits++;
518	else
519		STp->nbr_finished++;
520#endif
521	wait_for_completion(&(STp->wait));
522	STp->buffer->last_SRpnt->waiting = NULL;
523
524	STp->buffer->syscall_result = osst_chk_result(STp, STp->buffer->last_SRpnt);
525
526	if (STp->buffer->syscall_result)
527		STp->buffer->syscall_result =
528			osst_write_error_recovery(STp, &(STp->buffer->last_SRpnt), 1);
529	else
530		STp->first_frame_position++;
531
532	osst_release_request(STp->buffer->last_SRpnt);
533
534	if (STbuffer->writing < STbuffer->buffer_bytes)
535		printk(KERN_WARNING "osst :A: write_behind_check: something left in buffer!\n");
536
537	STbuffer->last_SRpnt = NULL;
538	STbuffer->buffer_bytes -= STbuffer->writing;
539	STbuffer->writing = 0;
540
541	return;
542}
543
544
545
546/* Onstream specific Routines */
547/*
548 * Initialize the OnStream AUX
549 */
550static void osst_init_aux(struct osst_tape * STp, int frame_type, int frame_seq_number,
551					 int logical_blk_num, int blk_sz, int blk_cnt)
552{
553	os_aux_t       *aux = STp->buffer->aux;
554	os_partition_t *par = &aux->partition;
555	os_dat_t       *dat = &aux->dat;
556
557	if (STp->raw) return;
558
559	memset(aux, 0, sizeof(*aux));
560	aux->format_id = htonl(0);
561	memcpy(aux->application_sig, "LIN4", 4);
562	aux->hdwr = htonl(0);
563	aux->frame_type = frame_type;
564
565	switch (frame_type) {
566	  case	OS_FRAME_TYPE_HEADER:
567		aux->update_frame_cntr    = htonl(STp->update_frame_cntr);
568		par->partition_num        = OS_CONFIG_PARTITION;
569		par->par_desc_ver         = OS_PARTITION_VERSION;
570		par->wrt_pass_cntr        = htons(0xffff);
571		/* 0-4 = reserved, 5-9 = header, 2990-2994 = header, 2995-2999 = reserved */
572		par->first_frame_ppos     = htonl(0);
573		par->last_frame_ppos      = htonl(0xbb7);
574		aux->frame_seq_num        = htonl(0);
575		aux->logical_blk_num_high = htonl(0);
576		aux->logical_blk_num      = htonl(0);
577		aux->next_mark_ppos       = htonl(STp->first_mark_ppos);
578		break;
579	  case	OS_FRAME_TYPE_DATA:
580	  case	OS_FRAME_TYPE_MARKER:
581		dat->dat_sz = 8;
582		dat->reserved1 = 0;
583		dat->entry_cnt = 1;
584		dat->reserved3 = 0;
585		dat->dat_list[0].blk_sz   = htonl(blk_sz);
586		dat->dat_list[0].blk_cnt  = htons(blk_cnt);
587		dat->dat_list[0].flags    = frame_type==OS_FRAME_TYPE_MARKER?
588							OS_DAT_FLAGS_MARK:OS_DAT_FLAGS_DATA;
589		dat->dat_list[0].reserved = 0;
590	  case	OS_FRAME_TYPE_EOD:
591		aux->update_frame_cntr    = htonl(0);
592		par->partition_num        = OS_DATA_PARTITION;
593		par->par_desc_ver         = OS_PARTITION_VERSION;
594		par->wrt_pass_cntr        = htons(STp->wrt_pass_cntr);
595		par->first_frame_ppos     = htonl(STp->first_data_ppos);
596		par->last_frame_ppos      = htonl(STp->capacity);
597		aux->frame_seq_num        = htonl(frame_seq_number);
598		aux->logical_blk_num_high = htonl(0);
599		aux->logical_blk_num      = htonl(logical_blk_num);
600		break;
601	  default: ; /* probably FILL */
602	}
603	aux->filemark_cnt = htonl(STp->filemark_cnt);
604	aux->phys_fm = htonl(0xffffffff);
605	aux->last_mark_ppos = htonl(STp->last_mark_ppos);
606	aux->last_mark_lbn  = htonl(STp->last_mark_lbn);
607}
608
609/*
610 * Verify that we have the correct tape frame
611 */
612static int osst_verify_frame(struct osst_tape * STp, int frame_seq_number, int quiet)
613{
614	char               * name = tape_name(STp);
615	os_aux_t           * aux  = STp->buffer->aux;
616	os_partition_t     * par  = &(aux->partition);
617	struct st_partstat * STps = &(STp->ps[STp->partition]);
618	int		     blk_cnt, blk_sz, i;
619
620	if (STp->raw) {
621		if (STp->buffer->syscall_result) {
622			for (i=0; i < STp->buffer->sg_segs; i++)
623				memset(page_address(sg_page(&STp->buffer->sg[i])),
624				       0, STp->buffer->sg[i].length);
625			strcpy(STp->buffer->b_data, "READ ERROR ON FRAME");
626                } else
627			STp->buffer->buffer_bytes = OS_FRAME_SIZE;
628		return 1;
629	}
630	if (STp->buffer->syscall_result) {
631#if DEBUG
632		printk(OSST_DEB_MSG "%s:D: Skipping frame, read error\n", name);
633#endif
634		return 0;
635	}
636	if (ntohl(aux->format_id) != 0) {
637#if DEBUG
638		printk(OSST_DEB_MSG "%s:D: Skipping frame, format_id %u\n", name, ntohl(aux->format_id));
639#endif
640		goto err_out;
641	}
642	if (memcmp(aux->application_sig, STp->application_sig, 4) != 0 &&
643	    (memcmp(aux->application_sig, "LIN3", 4) != 0 || STp->linux_media_version != 4)) {
644#if DEBUG
645		printk(OSST_DEB_MSG "%s:D: Skipping frame, incorrect application signature\n", name);
646#endif
647		goto err_out;
648	}
649	if (par->partition_num != OS_DATA_PARTITION) {
650		if (!STp->linux_media || STp->linux_media_version != 2) {
651#if DEBUG
652			printk(OSST_DEB_MSG "%s:D: Skipping frame, partition num %d\n",
653					    name, par->partition_num);
654#endif
655			goto err_out;
656		}
657	}
658	if (par->par_desc_ver != OS_PARTITION_VERSION) {
659#if DEBUG
660		printk(OSST_DEB_MSG "%s:D: Skipping frame, partition version %d\n", name, par->par_desc_ver);
661#endif
662		goto err_out;
663	}
664	if (ntohs(par->wrt_pass_cntr) != STp->wrt_pass_cntr) {
665#if DEBUG
666		printk(OSST_DEB_MSG "%s:D: Skipping frame, wrt_pass_cntr %d (expected %d)\n",
667				    name, ntohs(par->wrt_pass_cntr), STp->wrt_pass_cntr);
668#endif
669		goto err_out;
670	}
671	if (aux->frame_type != OS_FRAME_TYPE_DATA &&
672	    aux->frame_type != OS_FRAME_TYPE_EOD &&
673	    aux->frame_type != OS_FRAME_TYPE_MARKER) {
674		if (!quiet) {
675#if DEBUG
676			printk(OSST_DEB_MSG "%s:D: Skipping frame, frame type %x\n", name, aux->frame_type);
677#endif
678		}
679		goto err_out;
680	}
681	if (aux->frame_type == OS_FRAME_TYPE_EOD &&
682	    STp->first_frame_position < STp->eod_frame_ppos) {
683		printk(KERN_INFO "%s:I: Skipping premature EOD frame %d\n", name,
684				 STp->first_frame_position);
685		goto err_out;
686	}
687        if (frame_seq_number != -1 && ntohl(aux->frame_seq_num) != frame_seq_number) {
688		if (!quiet) {
689#if DEBUG
690			printk(OSST_DEB_MSG "%s:D: Skipping frame, sequence number %u (expected %d)\n",
691					    name, ntohl(aux->frame_seq_num), frame_seq_number);
692#endif
693		}
694		goto err_out;
695	}
696	if (aux->frame_type == OS_FRAME_TYPE_MARKER) {
697		STps->eof = ST_FM_HIT;
698
699		i = ntohl(aux->filemark_cnt);
700		if (STp->header_cache != NULL && i < OS_FM_TAB_MAX && (i > STp->filemark_cnt ||
701		    STp->first_frame_position - 1 != ntohl(STp->header_cache->dat_fm_tab.fm_tab_ent[i]))) {
702#if DEBUG
703			printk(OSST_DEB_MSG "%s:D: %s filemark %d at frame pos %d\n", name,
704				  STp->header_cache->dat_fm_tab.fm_tab_ent[i] == 0?"Learned":"Corrected",
705				  i, STp->first_frame_position - 1);
706#endif
707			STp->header_cache->dat_fm_tab.fm_tab_ent[i] = htonl(STp->first_frame_position - 1);
708			if (i >= STp->filemark_cnt)
709				 STp->filemark_cnt = i+1;
710		}
711	}
712	if (aux->frame_type == OS_FRAME_TYPE_EOD) {
713		STps->eof = ST_EOD_1;
714		STp->frame_in_buffer = 1;
715	}
716	if (aux->frame_type == OS_FRAME_TYPE_DATA) {
717                blk_cnt = ntohs(aux->dat.dat_list[0].blk_cnt);
718		blk_sz  = ntohl(aux->dat.dat_list[0].blk_sz);
719		STp->buffer->buffer_bytes = blk_cnt * blk_sz;
720		STp->buffer->read_pointer = 0;
721		STp->frame_in_buffer = 1;
722
723		/* See what block size was used to write file */
724		if (STp->block_size != blk_sz && blk_sz > 0) {
725			printk(KERN_INFO
726	    	"%s:I: File was written with block size %d%c, currently %d%c, adjusted to match.\n",
727       				name, blk_sz<1024?blk_sz:blk_sz/1024,blk_sz<1024?'b':'k',
728				STp->block_size<1024?STp->block_size:STp->block_size/1024,
729				STp->block_size<1024?'b':'k');
730			STp->block_size            = blk_sz;
731			STp->buffer->buffer_blocks = OS_DATA_SIZE / blk_sz;
732		}
733		STps->eof = ST_NOEOF;
734	}
735        STp->frame_seq_number = ntohl(aux->frame_seq_num);
736	STp->logical_blk_num  = ntohl(aux->logical_blk_num);
737	return 1;
738
739err_out:
740	if (STp->read_error_frame == 0)
741		STp->read_error_frame = STp->first_frame_position - 1;
742	return 0;
743}
744
745/*
746 * Wait for the unit to become Ready
747 */
748static int osst_wait_ready(struct osst_tape * STp, struct osst_request ** aSRpnt,
749				 unsigned timeout, int initial_delay)
750{
751	unsigned char		cmd[MAX_COMMAND_SIZE];
752	struct osst_request   * SRpnt;
753	unsigned long		startwait = jiffies;
754#if DEBUG
755	int			dbg  = debugging;
756	char    	      * name = tape_name(STp);
757
758	printk(OSST_DEB_MSG "%s:D: Reached onstream wait ready\n", name);
759#endif
760
761	if (initial_delay > 0)
762		msleep(jiffies_to_msecs(initial_delay));
763
764	memset(cmd, 0, MAX_COMMAND_SIZE);
765	cmd[0] = TEST_UNIT_READY;
766
767	SRpnt = osst_do_scsi(*aSRpnt, STp, cmd, 0, DMA_NONE, STp->timeout, MAX_RETRIES, 1);
768	*aSRpnt = SRpnt;
769	if (!SRpnt) return (-EBUSY);
770
771	while ( STp->buffer->syscall_result && time_before(jiffies, startwait + timeout*HZ) &&
772	       (( SRpnt->sense[2]  == 2 && SRpnt->sense[12] == 4    &&
773		 (SRpnt->sense[13] == 1 || SRpnt->sense[13] == 8)    ) ||
774		( SRpnt->sense[2]  == 6 && SRpnt->sense[12] == 0x28 &&
775		  SRpnt->sense[13] == 0                                        )  )) {
776#if DEBUG
777	    if (debugging) {
778		printk(OSST_DEB_MSG "%s:D: Sleeping in onstream wait ready\n", name);
779		printk(OSST_DEB_MSG "%s:D: Turning off debugging for a while\n", name);
780		debugging = 0;
781	    }
782#endif
783	    msleep(100);
784
785	    memset(cmd, 0, MAX_COMMAND_SIZE);
786	    cmd[0] = TEST_UNIT_READY;
787
788	    SRpnt = osst_do_scsi(SRpnt, STp, cmd, 0, DMA_NONE, STp->timeout, MAX_RETRIES, 1);
789	}
790	*aSRpnt = SRpnt;
791#if DEBUG
792	debugging = dbg;
793#endif
794	if ( STp->buffer->syscall_result &&
795	     osst_write_error_recovery(STp, aSRpnt, 0) ) {
796#if DEBUG
797	    printk(OSST_DEB_MSG "%s:D: Abnormal exit from onstream wait ready\n", name);
798	    printk(OSST_DEB_MSG "%s:D: Result = %d, Sense: 0=%02x, 2=%02x, 12=%02x, 13=%02x\n", name,
799			STp->buffer->syscall_result, SRpnt->sense[0], SRpnt->sense[2],
800			SRpnt->sense[12], SRpnt->sense[13]);
801#endif
802	    return (-EIO);
803	}
804#if DEBUG
805	printk(OSST_DEB_MSG "%s:D: Normal exit from onstream wait ready\n", name);
806#endif
807	return 0;
808}
809
810/*
811 * Wait for a tape to be inserted in the unit
812 */
813static int osst_wait_for_medium(struct osst_tape * STp, struct osst_request ** aSRpnt, unsigned timeout)
814{
815	unsigned char		cmd[MAX_COMMAND_SIZE];
816	struct osst_request   * SRpnt;
817	unsigned long		startwait = jiffies;
818#if DEBUG
819	int			dbg = debugging;
820	char    	      * name = tape_name(STp);
821
822	printk(OSST_DEB_MSG "%s:D: Reached onstream wait for medium\n", name);
823#endif
824
825	memset(cmd, 0, MAX_COMMAND_SIZE);
826	cmd[0] = TEST_UNIT_READY;
827
828	SRpnt = osst_do_scsi(*aSRpnt, STp, cmd, 0, DMA_NONE, STp->timeout, MAX_RETRIES, 1);
829	*aSRpnt = SRpnt;
830	if (!SRpnt) return (-EBUSY);
831
832	while ( STp->buffer->syscall_result && time_before(jiffies, startwait + timeout*HZ) &&
833		SRpnt->sense[2] == 2 && SRpnt->sense[12] == 0x3a && SRpnt->sense[13] == 0  ) {
834#if DEBUG
835	    if (debugging) {
836		printk(OSST_DEB_MSG "%s:D: Sleeping in onstream wait medium\n", name);
837		printk(OSST_DEB_MSG "%s:D: Turning off debugging for a while\n", name);
838		debugging = 0;
839	    }
840#endif
841	    msleep(100);
842
843	    memset(cmd, 0, MAX_COMMAND_SIZE);
844	    cmd[0] = TEST_UNIT_READY;
845
846	    SRpnt = osst_do_scsi(SRpnt, STp, cmd, 0, DMA_NONE, STp->timeout, MAX_RETRIES, 1);
847	}
848	*aSRpnt = SRpnt;
849#if DEBUG
850	debugging = dbg;
851#endif
852	if ( STp->buffer->syscall_result     && SRpnt->sense[2]  != 2 &&
853	     SRpnt->sense[12] != 4 && SRpnt->sense[13] == 1) {
854#if DEBUG
855	    printk(OSST_DEB_MSG "%s:D: Abnormal exit from onstream wait medium\n", name);
856	    printk(OSST_DEB_MSG "%s:D: Result = %d, Sense: 0=%02x, 2=%02x, 12=%02x, 13=%02x\n", name,
857			STp->buffer->syscall_result, SRpnt->sense[0], SRpnt->sense[2],
858			SRpnt->sense[12], SRpnt->sense[13]);
859#endif
860	    return 0;
861	}
862#if DEBUG
863	printk(OSST_DEB_MSG "%s:D: Normal exit from onstream wait medium\n", name);
864#endif
865	return 1;
866}
867
868static int osst_position_tape_and_confirm(struct osst_tape * STp, struct osst_request ** aSRpnt, int frame)
869{
870	int	retval;
871
872	osst_wait_ready(STp, aSRpnt, 15 * 60, 0);			/* TODO - can this catch a write error? */
873	retval = osst_set_frame_position(STp, aSRpnt, frame, 0);
874	if (retval) return (retval);
875	osst_wait_ready(STp, aSRpnt, 15 * 60, OSST_WAIT_POSITION_COMPLETE);
876	return (osst_get_frame_position(STp, aSRpnt));
877}
878
879/*
880 * Wait for write(s) to complete
881 */
882static int osst_flush_drive_buffer(struct osst_tape * STp, struct osst_request ** aSRpnt)
883{
884	unsigned char		cmd[MAX_COMMAND_SIZE];
885	struct osst_request   * SRpnt;
886	int			result = 0;
887	int			delay  = OSST_WAIT_WRITE_COMPLETE;
888#if DEBUG
889	char		      * name = tape_name(STp);
890
891	printk(OSST_DEB_MSG "%s:D: Reached onstream flush drive buffer (write filemark)\n", name);
892#endif
893
894	memset(cmd, 0, MAX_COMMAND_SIZE);
895	cmd[0] = WRITE_FILEMARKS;
896	cmd[1] = 1;
897
898	SRpnt = osst_do_scsi(*aSRpnt, STp, cmd, 0, DMA_NONE, STp->timeout, MAX_RETRIES, 1);
899	*aSRpnt = SRpnt;
900	if (!SRpnt) return (-EBUSY);
901	if (STp->buffer->syscall_result) {
902		if ((SRpnt->sense[2] & 0x0f) == 2 && SRpnt->sense[12] == 4) {
903			if (SRpnt->sense[13] == 8) {
904				delay = OSST_WAIT_LONG_WRITE_COMPLETE;
905			}
906		} else
907			result = osst_write_error_recovery(STp, aSRpnt, 0);
908	}
909	result |= osst_wait_ready(STp, aSRpnt, 5 * 60, delay);
910	STp->ps[STp->partition].rw = OS_WRITING_COMPLETE;
911
912	return (result);
913}
914
915#define OSST_POLL_PER_SEC 10
916static int osst_wait_frame(struct osst_tape * STp, struct osst_request ** aSRpnt, int curr, int minlast, int to)
917{
918	unsigned long	startwait = jiffies;
919	char	      * name      = tape_name(STp);
920#if DEBUG
921	char	   notyetprinted  = 1;
922#endif
923	if (minlast >= 0 && STp->ps[STp->partition].rw != ST_READING)
924		printk(KERN_ERR "%s:A: Waiting for frame without having initialized read!\n", name);
925
926	while (time_before (jiffies, startwait + to*HZ))
927	{
928		int result;
929		result = osst_get_frame_position(STp, aSRpnt);
930		if (result == -EIO)
931			if ((result = osst_write_error_recovery(STp, aSRpnt, 0)) == 0)
932				return 0;	/* successful recovery leaves drive ready for frame */
933		if (result < 0) break;
934		if (STp->first_frame_position == curr &&
935		    ((minlast < 0 &&
936		      (signed)STp->last_frame_position > (signed)curr + minlast) ||
937		     (minlast >= 0 && STp->cur_frames > minlast)
938		    ) && result >= 0)
939		{
940#if DEBUG
941			if (debugging || time_after_eq(jiffies, startwait + 2*HZ/OSST_POLL_PER_SEC))
942				printk (OSST_DEB_MSG
943					"%s:D: Succ wait f fr %i (>%i): %i-%i %i (%i): %3li.%li s\n",
944					name, curr, curr+minlast, STp->first_frame_position,
945					STp->last_frame_position, STp->cur_frames,
946					result, (jiffies-startwait)/HZ,
947					(((jiffies-startwait)%HZ)*10)/HZ);
948#endif
949			return 0;
950		}
951#if DEBUG
952		if (time_after_eq(jiffies, startwait + 2*HZ/OSST_POLL_PER_SEC) && notyetprinted)
953		{
954			printk (OSST_DEB_MSG "%s:D: Wait for frame %i (>%i): %i-%i %i (%i)\n",
955				name, curr, curr+minlast, STp->first_frame_position,
956				STp->last_frame_position, STp->cur_frames, result);
957			notyetprinted--;
958		}
959#endif
960		msleep(1000 / OSST_POLL_PER_SEC);
961	}
962#if DEBUG
963	printk (OSST_DEB_MSG "%s:D: Fail wait f fr %i (>%i): %i-%i %i: %3li.%li s\n",
964		name, curr, curr+minlast, STp->first_frame_position,
965		STp->last_frame_position, STp->cur_frames,
966		(jiffies-startwait)/HZ, (((jiffies-startwait)%HZ)*10)/HZ);
967#endif
968	return -EBUSY;
969}
970
971static int osst_recover_wait_frame(struct osst_tape * STp, struct osst_request ** aSRpnt, int writing)
972{
973	struct osst_request   * SRpnt;
974	unsigned char		cmd[MAX_COMMAND_SIZE];
975	unsigned long   	startwait = jiffies;
976	int			retval    = 1;
977        char		      * name      = tape_name(STp);
978
979	if (writing) {
980		char	mybuf[24];
981		char  * olddata = STp->buffer->b_data;
982		int	oldsize = STp->buffer->buffer_size;
983
984		/* write zero fm then read pos - if shows write error, try to recover - if no progress, wait */
985
986		memset(cmd, 0, MAX_COMMAND_SIZE);
987		cmd[0] = WRITE_FILEMARKS;
988		cmd[1] = 1;
989		SRpnt = osst_do_scsi(*aSRpnt, STp, cmd, 0, DMA_NONE, STp->timeout,
990								MAX_RETRIES, 1);
991
992		while (retval && time_before (jiffies, startwait + 5*60*HZ)) {
993
994			if (STp->buffer->syscall_result && (SRpnt->sense[2] & 0x0f) != 2) {
995
996				/* some failure - not just not-ready */
997				retval = osst_write_error_recovery(STp, aSRpnt, 0);
998				break;
999			}
1000			schedule_timeout_interruptible(HZ / OSST_POLL_PER_SEC);
1001
1002			STp->buffer->b_data = mybuf; STp->buffer->buffer_size = 24;
1003			memset(cmd, 0, MAX_COMMAND_SIZE);
1004			cmd[0] = READ_POSITION;
1005
1006			SRpnt = osst_do_scsi(SRpnt, STp, cmd, 20, DMA_FROM_DEVICE, STp->timeout,
1007										MAX_RETRIES, 1);
1008
1009			retval = ( STp->buffer->syscall_result || (STp->buffer)->b_data[15] > 25 );
1010			STp->buffer->b_data = olddata; STp->buffer->buffer_size = oldsize;
1011		}
1012		if (retval)
1013			printk(KERN_ERR "%s:E: Device did not succeed to write buffered data\n", name);
1014	} else
1015		/* TODO - figure out which error conditions can be handled */
1016		if (STp->buffer->syscall_result)
1017			printk(KERN_WARNING
1018				"%s:W: Recover_wait_frame(read) cannot handle %02x:%02x:%02x\n", name,
1019					(*aSRpnt)->sense[ 2] & 0x0f,
1020					(*aSRpnt)->sense[12],
1021					(*aSRpnt)->sense[13]);
1022
1023	return retval;
1024}
1025
1026/*
1027 * Read the next OnStream tape frame at the current location
1028 */
1029static int osst_read_frame(struct osst_tape * STp, struct osst_request ** aSRpnt, int timeout)
1030{
1031	unsigned char		cmd[MAX_COMMAND_SIZE];
1032	struct osst_request   * SRpnt;
1033	int			retval = 0;
1034#if DEBUG
1035	os_aux_t	      * aux    = STp->buffer->aux;
1036	char		      * name   = tape_name(STp);
1037#endif
1038
1039	if (STp->poll)
1040		if (osst_wait_frame (STp, aSRpnt, STp->first_frame_position, 0, timeout))
1041			retval = osst_recover_wait_frame(STp, aSRpnt, 0);
1042
1043	memset(cmd, 0, MAX_COMMAND_SIZE);
1044	cmd[0] = READ_6;
1045	cmd[1] = 1;
1046	cmd[4] = 1;
1047
1048#if DEBUG
1049	if (debugging)
1050		printk(OSST_DEB_MSG "%s:D: Reading frame from OnStream tape\n", name);
1051#endif
1052	SRpnt = osst_do_scsi(*aSRpnt, STp, cmd, OS_FRAME_SIZE, DMA_FROM_DEVICE,
1053				      STp->timeout, MAX_RETRIES, 1);
1054	*aSRpnt = SRpnt;
1055	if (!SRpnt)
1056		return (-EBUSY);
1057
1058	if ((STp->buffer)->syscall_result) {
1059	    retval = 1;
1060	    if (STp->read_error_frame == 0) {
1061		STp->read_error_frame = STp->first_frame_position;
1062#if DEBUG
1063		printk(OSST_DEB_MSG "%s:D: Recording read error at %d\n", name, STp->read_error_frame);
1064#endif
1065	    }
1066#if DEBUG
1067	    if (debugging)
1068		printk(OSST_DEB_MSG "%s:D: Sense: %2x %2x %2x %2x %2x %2x %2x %2x\n",
1069		   name,
1070		   SRpnt->sense[0], SRpnt->sense[1],
1071		   SRpnt->sense[2], SRpnt->sense[3],
1072		   SRpnt->sense[4], SRpnt->sense[5],
1073		   SRpnt->sense[6], SRpnt->sense[7]);
1074#endif
1075	}
1076	else
1077	    STp->first_frame_position++;
1078#if DEBUG
1079	if (debugging) {
1080	   char sig[8]; int i;
1081	   for (i=0;i<4;i++)
1082		   sig[i] = aux->application_sig[i]<32?'^':aux->application_sig[i];
1083	   sig[4] = '\0';
1084	   printk(OSST_DEB_MSG
1085		"%s:D: AUX: %s UpdFrCt#%d Wpass#%d %s FrSeq#%d LogBlk#%d Qty=%d Sz=%d\n", name, sig,
1086			ntohl(aux->update_frame_cntr), ntohs(aux->partition.wrt_pass_cntr),
1087			aux->frame_type==1?"EOD":aux->frame_type==2?"MARK":
1088			aux->frame_type==8?"HEADR":aux->frame_type==0x80?"DATA":"FILL",
1089			ntohl(aux->frame_seq_num), ntohl(aux->logical_blk_num),
1090			ntohs(aux->dat.dat_list[0].blk_cnt), ntohl(aux->dat.dat_list[0].blk_sz) );
1091	   if (aux->frame_type==2)
1092		printk(OSST_DEB_MSG "%s:D: mark_cnt=%d, last_mark_ppos=%d, last_mark_lbn=%d\n", name,
1093			ntohl(aux->filemark_cnt), ntohl(aux->last_mark_ppos), ntohl(aux->last_mark_lbn));
1094	   printk(OSST_DEB_MSG "%s:D: Exit read frame from OnStream tape with code %d\n", name, retval);
1095	}
1096#endif
1097	return (retval);
1098}
1099
1100static int osst_initiate_read(struct osst_tape * STp, struct osst_request ** aSRpnt)
1101{
1102	struct st_partstat    * STps   = &(STp->ps[STp->partition]);
1103	struct osst_request   * SRpnt  ;
1104	unsigned char		cmd[MAX_COMMAND_SIZE];
1105	int			retval = 0;
1106	char		      * name   = tape_name(STp);
1107
1108	if (STps->rw != ST_READING) {         /* Initialize read operation */
1109		if (STps->rw == ST_WRITING || STp->dirty) {
1110			STp->write_type = OS_WRITE_DATA;
1111                        osst_flush_write_buffer(STp, aSRpnt);
1112			osst_flush_drive_buffer(STp, aSRpnt);
1113		}
1114		STps->rw = ST_READING;
1115		STp->frame_in_buffer = 0;
1116
1117		/*
1118		 *      Issue a read 0 command to get the OnStream drive
1119                 *      read frames into its buffer.
1120		 */
1121		memset(cmd, 0, MAX_COMMAND_SIZE);
1122		cmd[0] = READ_6;
1123		cmd[1] = 1;
1124
1125#if DEBUG
1126		printk(OSST_DEB_MSG "%s:D: Start Read Ahead on OnStream tape\n", name);
1127#endif
1128		SRpnt   = osst_do_scsi(*aSRpnt, STp, cmd, 0, DMA_NONE, STp->timeout, MAX_RETRIES, 1);
1129		*aSRpnt = SRpnt;
1130		if ((retval = STp->buffer->syscall_result))
1131			printk(KERN_WARNING "%s:W: Error starting read ahead\n", name);
1132	}
1133
1134	return retval;
1135}
1136
1137static int osst_get_logical_frame(struct osst_tape * STp, struct osst_request ** aSRpnt,
1138						int frame_seq_number, int quiet)
1139{
1140	struct st_partstat * STps  = &(STp->ps[STp->partition]);
1141	char		   * name  = tape_name(STp);
1142	int		     cnt   = 0,
1143			     bad   = 0,
1144			     past  = 0,
1145			     x,
1146			     position;
1147
1148	/*
1149	 * If we want just any frame (-1) and there is a frame in the buffer, return it
1150	 */
1151	if (frame_seq_number == -1 && STp->frame_in_buffer) {
1152#if DEBUG
1153		printk(OSST_DEB_MSG "%s:D: Frame %d still in buffer\n", name, STp->frame_seq_number);
1154#endif
1155		return (STps->eof);
1156	}
1157	/*
1158         * Search and wait for the next logical tape frame
1159	 */
1160	while (1) {
1161		if (cnt++ > 400) {
1162                        printk(KERN_ERR "%s:E: Couldn't find logical frame %d, aborting\n",
1163					    name, frame_seq_number);
1164			if (STp->read_error_frame) {
1165				osst_set_frame_position(STp, aSRpnt, STp->read_error_frame, 0);
1166#if DEBUG
1167                        	printk(OSST_DEB_MSG "%s:D: Repositioning tape to bad frame %d\n",
1168						    name, STp->read_error_frame);
1169#endif
1170				STp->read_error_frame = 0;
1171				STp->abort_count++;
1172			}
1173			return (-EIO);
1174		}
1175#if DEBUG
1176		if (debugging)
1177			printk(OSST_DEB_MSG "%s:D: Looking for frame %d, attempt %d\n",
1178					  name, frame_seq_number, cnt);
1179#endif
1180		if ( osst_initiate_read(STp, aSRpnt)
1181                || ( (!STp->frame_in_buffer) && osst_read_frame(STp, aSRpnt, 30) ) ) {
1182			if (STp->raw)
1183				return (-EIO);
1184			position = osst_get_frame_position(STp, aSRpnt);
1185			if (position >= 0xbae && position < 0xbb8)
1186				position = 0xbb8;
1187			else if (position > STp->eod_frame_ppos || ++bad == 10) {
1188				position = STp->read_error_frame - 1;
1189				bad = 0;
1190			}
1191			else {
1192				position += 29;
1193				cnt      += 19;
1194			}
1195#if DEBUG
1196			printk(OSST_DEB_MSG "%s:D: Bad frame detected, positioning tape to block %d\n",
1197					 name, position);
1198#endif
1199			osst_set_frame_position(STp, aSRpnt, position, 0);
1200			continue;
1201		}
1202		if (osst_verify_frame(STp, frame_seq_number, quiet))
1203			break;
1204		if (osst_verify_frame(STp, -1, quiet)) {
1205			x = ntohl(STp->buffer->aux->frame_seq_num);
1206			if (STp->fast_open) {
1207				printk(KERN_WARNING
1208				       "%s:W: Found logical frame %d instead of %d after fast open\n",
1209				       name, x, frame_seq_number);
1210				STp->header_ok = 0;
1211				STp->read_error_frame = 0;
1212				return (-EIO);
1213			}
1214			if (x > frame_seq_number) {
1215				if (++past > 3) {
1216					/* positioning backwards did not bring us to the desired frame */
1217					position = STp->read_error_frame - 1;
1218				}
1219				else {
1220			        	position = osst_get_frame_position(STp, aSRpnt)
1221					         + frame_seq_number - x - 1;
1222
1223					if (STp->first_frame_position >= 3000 && position < 3000)
1224						position -= 10;
1225				}
1226#if DEBUG
1227                                printk(OSST_DEB_MSG
1228				       "%s:D: Found logical frame %d while looking for %d: back up %d\n",
1229						name, x, frame_seq_number,
1230					       	STp->first_frame_position - position);
1231#endif
1232                        	osst_set_frame_position(STp, aSRpnt, position, 0);
1233				cnt += 10;
1234			}
1235			else
1236				past = 0;
1237		}
1238		if (osst_get_frame_position(STp, aSRpnt) == 0xbaf) {
1239#if DEBUG
1240			printk(OSST_DEB_MSG "%s:D: Skipping config partition\n", name);
1241#endif
1242			osst_set_frame_position(STp, aSRpnt, 0xbb8, 0);
1243			cnt--;
1244		}
1245		STp->frame_in_buffer = 0;
1246	}
1247	if (cnt > 1) {
1248		STp->recover_count++;
1249		STp->recover_erreg++;
1250		printk(KERN_WARNING "%s:I: Don't worry, Read error at position %d recovered\n",
1251					name, STp->read_error_frame);
1252 	}
1253	STp->read_count++;
1254
1255#if DEBUG
1256	if (debugging || STps->eof)
1257		printk(OSST_DEB_MSG
1258			"%s:D: Exit get logical frame (%d=>%d) from OnStream tape with code %d\n",
1259			name, frame_seq_number, STp->frame_seq_number, STps->eof);
1260#endif
1261	STp->fast_open = 0;
1262	STp->read_error_frame = 0;
1263	return (STps->eof);
1264}
1265
1266static int osst_seek_logical_blk(struct osst_tape * STp, struct osst_request ** aSRpnt, int logical_blk_num)
1267{
1268        struct st_partstat * STps = &(STp->ps[STp->partition]);
1269	char		   * name = tape_name(STp);
1270	int	retries    = 0;
1271	int	frame_seq_estimate, ppos_estimate, move;
1272
1273	if (logical_blk_num < 0) logical_blk_num = 0;
1274#if DEBUG
1275	printk(OSST_DEB_MSG "%s:D: Seeking logical block %d (now at %d, size %d%c)\n",
1276				name, logical_blk_num, STp->logical_blk_num,
1277				STp->block_size<1024?STp->block_size:STp->block_size/1024,
1278				STp->block_size<1024?'b':'k');
1279#endif
1280	/* Do we know where we are? */
1281	if (STps->drv_block >= 0) {
1282		move                = logical_blk_num - STp->logical_blk_num;
1283		if (move < 0) move -= (OS_DATA_SIZE / STp->block_size) - 1;
1284		move               /= (OS_DATA_SIZE / STp->block_size);
1285		frame_seq_estimate  = STp->frame_seq_number + move;
1286	} else
1287		frame_seq_estimate  = logical_blk_num * STp->block_size / OS_DATA_SIZE;
1288
1289	if (frame_seq_estimate < 2980) ppos_estimate = frame_seq_estimate + 10;
1290	else			       ppos_estimate = frame_seq_estimate + 20;
1291	while (++retries < 10) {
1292	   if (ppos_estimate > STp->eod_frame_ppos-2) {
1293	       frame_seq_estimate += STp->eod_frame_ppos - 2 - ppos_estimate;
1294	       ppos_estimate       = STp->eod_frame_ppos - 2;
1295	   }
1296	   if (frame_seq_estimate < 0) {
1297	       frame_seq_estimate = 0;
1298	       ppos_estimate      = 10;
1299	   }
1300	   osst_set_frame_position(STp, aSRpnt, ppos_estimate, 0);
1301	   if (osst_get_logical_frame(STp, aSRpnt, frame_seq_estimate, 1) >= 0) {
1302	      /* we've located the estimated frame, now does it have our block? */
1303	      if (logical_blk_num <  STp->logical_blk_num ||
1304	          logical_blk_num >= STp->logical_blk_num + ntohs(STp->buffer->aux->dat.dat_list[0].blk_cnt)) {
1305		 if (STps->eof == ST_FM_HIT)
1306		    move = logical_blk_num < STp->logical_blk_num? -2 : 1;
1307		 else {
1308		    move                = logical_blk_num - STp->logical_blk_num;
1309		    if (move < 0) move -= (OS_DATA_SIZE / STp->block_size) - 1;
1310		    move               /= (OS_DATA_SIZE / STp->block_size);
1311		 }
1312		 if (!move) move = logical_blk_num > STp->logical_blk_num ? 1 : -1;
1313#if DEBUG
1314		 printk(OSST_DEB_MSG
1315			"%s:D: Seek retry %d at ppos %d fsq %d (est %d) lbn %d (need %d) move %d\n",
1316				name, retries, ppos_estimate, STp->frame_seq_number, frame_seq_estimate,
1317				STp->logical_blk_num, logical_blk_num, move);
1318#endif
1319		 frame_seq_estimate += move;
1320		 ppos_estimate      += move;
1321		 continue;
1322	      } else {
1323		 STp->buffer->read_pointer  = (logical_blk_num - STp->logical_blk_num) * STp->block_size;
1324		 STp->buffer->buffer_bytes -= STp->buffer->read_pointer;
1325		 STp->logical_blk_num       =  logical_blk_num;
1326#if DEBUG
1327		 printk(OSST_DEB_MSG
1328			"%s:D: Seek success at ppos %d fsq %d in_buf %d, bytes %d, ptr %d*%d\n",
1329				name, ppos_estimate, STp->frame_seq_number, STp->frame_in_buffer,
1330				STp->buffer->buffer_bytes, STp->buffer->read_pointer / STp->block_size,
1331				STp->block_size);
1332#endif
1333		 STps->drv_file = ntohl(STp->buffer->aux->filemark_cnt);
1334		 if (STps->eof == ST_FM_HIT) {
1335		     STps->drv_file++;
1336		     STps->drv_block = 0;
1337		 } else {
1338		     STps->drv_block = ntohl(STp->buffer->aux->last_mark_lbn)?
1339					  STp->logical_blk_num -
1340					     (STps->drv_file ? ntohl(STp->buffer->aux->last_mark_lbn) + 1 : 0):
1341					-1;
1342		 }
1343		 STps->eof = (STp->first_frame_position >= STp->eod_frame_ppos)?ST_EOD:ST_NOEOF;
1344		 return 0;
1345	      }
1346	   }
1347	   if (osst_get_logical_frame(STp, aSRpnt, -1, 1) < 0)
1348	      goto error;
1349	   /* we are not yet at the estimated frame, adjust our estimate of its physical position */
1350#if DEBUG
1351	   printk(OSST_DEB_MSG "%s:D: Seek retry %d at ppos %d fsq %d (est %d) lbn %d (need %d)\n",
1352			   name, retries, ppos_estimate, STp->frame_seq_number, frame_seq_estimate,
1353			   STp->logical_blk_num, logical_blk_num);
1354#endif
1355	   if (frame_seq_estimate != STp->frame_seq_number)
1356	      ppos_estimate += frame_seq_estimate - STp->frame_seq_number;
1357	   else
1358	      break;
1359	}
1360error:
1361	printk(KERN_ERR "%s:E: Couldn't seek to logical block %d (at %d), %d retries\n",
1362			    name, logical_blk_num, STp->logical_blk_num, retries);
1363	return (-EIO);
1364}
1365
1366/* The values below are based on the OnStream frame payload size of 32K == 2**15,
1367 * that is, OSST_FRAME_SHIFT + OSST_SECTOR_SHIFT must be 15. With a minimum block
1368 * size of 512 bytes, we need to be able to resolve 32K/512 == 64 == 2**6 positions
1369 * inside each frame. Finally, OSST_SECTOR_MASK == 2**OSST_FRAME_SHIFT - 1.
1370 */
1371#define OSST_FRAME_SHIFT  6
1372#define OSST_SECTOR_SHIFT 9
1373#define OSST_SECTOR_MASK  0x03F
1374
1375static int osst_get_sector(struct osst_tape * STp, struct osst_request ** aSRpnt)
1376{
1377	int	sector;
1378#if DEBUG
1379	char  * name = tape_name(STp);
1380
1381	printk(OSST_DEB_MSG
1382		"%s:D: Positioned at ppos %d, frame %d, lbn %d, file %d, blk %d, %cptr %d, eof %d\n",
1383		name, STp->first_frame_position, STp->frame_seq_number, STp->logical_blk_num,
1384		STp->ps[STp->partition].drv_file, STp->ps[STp->partition].drv_block,
1385		STp->ps[STp->partition].rw == ST_WRITING?'w':'r',
1386		STp->ps[STp->partition].rw == ST_WRITING?STp->buffer->buffer_bytes:
1387		STp->buffer->read_pointer, STp->ps[STp->partition].eof);
1388#endif
1389	/* do we know where we are inside a file? */
1390	if (STp->ps[STp->partition].drv_block >= 0) {
1391		sector = (STp->frame_in_buffer ? STp->first_frame_position-1 :
1392				STp->first_frame_position) << OSST_FRAME_SHIFT;
1393		if (STp->ps[STp->partition].rw == ST_WRITING)
1394		       	sector |= (STp->buffer->buffer_bytes >> OSST_SECTOR_SHIFT) & OSST_SECTOR_MASK;
1395		else
1396	       		sector |= (STp->buffer->read_pointer >> OSST_SECTOR_SHIFT) & OSST_SECTOR_MASK;
1397	} else {
1398		sector = osst_get_frame_position(STp, aSRpnt);
1399		if (sector > 0)
1400			sector <<= OSST_FRAME_SHIFT;
1401	}
1402	return sector;
1403}
1404
1405static int osst_seek_sector(struct osst_tape * STp, struct osst_request ** aSRpnt, int sector)
1406{
1407        struct st_partstat * STps   = &(STp->ps[STp->partition]);
1408	int		     frame  = sector >> OSST_FRAME_SHIFT,
1409			     offset = (sector & OSST_SECTOR_MASK) << OSST_SECTOR_SHIFT,
1410			     r;
1411#if DEBUG
1412	char          * name = tape_name(STp);
1413
1414	printk(OSST_DEB_MSG "%s:D: Seeking sector %d in frame %d at offset %d\n",
1415				name, sector, frame, offset);
1416#endif
1417	if (frame < 0 || frame >= STp->capacity) return (-ENXIO);
1418
1419	if (frame <= STp->first_data_ppos) {
1420		STp->frame_seq_number = STp->logical_blk_num = STps->drv_file = STps->drv_block = 0;
1421		return (osst_set_frame_position(STp, aSRpnt, frame, 0));
1422	}
1423	r = osst_set_frame_position(STp, aSRpnt, offset?frame:frame-1, 0);
1424	if (r < 0) return r;
1425
1426	r = osst_get_logical_frame(STp, aSRpnt, -1, 1);
1427	if (r < 0) return r;
1428
1429	if (osst_get_frame_position(STp, aSRpnt) != (offset?frame+1:frame)) return (-EIO);
1430
1431	if (offset) {
1432		STp->logical_blk_num      += offset / STp->block_size;
1433		STp->buffer->read_pointer  = offset;
1434		STp->buffer->buffer_bytes -= offset;
1435	} else {
1436		STp->frame_seq_number++;
1437		STp->frame_in_buffer       = 0;
1438		STp->logical_blk_num      += ntohs(STp->buffer->aux->dat.dat_list[0].blk_cnt);
1439		STp->buffer->buffer_bytes  = STp->buffer->read_pointer = 0;
1440	}
1441	STps->drv_file = ntohl(STp->buffer->aux->filemark_cnt);
1442	if (STps->eof == ST_FM_HIT) {
1443		STps->drv_file++;
1444		STps->drv_block = 0;
1445	} else {
1446		STps->drv_block = ntohl(STp->buffer->aux->last_mark_lbn)?
1447				    STp->logical_blk_num -
1448					(STps->drv_file ? ntohl(STp->buffer->aux->last_mark_lbn) + 1 : 0):
1449				  -1;
1450	}
1451	STps->eof       = (STp->first_frame_position >= STp->eod_frame_ppos)?ST_EOD:ST_NOEOF;
1452#if DEBUG
1453	printk(OSST_DEB_MSG
1454		"%s:D: Now positioned at ppos %d, frame %d, lbn %d, file %d, blk %d, rptr %d, eof %d\n",
1455		name, STp->first_frame_position, STp->frame_seq_number, STp->logical_blk_num,
1456		STps->drv_file, STps->drv_block, STp->buffer->read_pointer, STps->eof);
1457#endif
1458	return 0;
1459}
1460
1461/*
1462 * Read back the drive's internal buffer contents, as a part
1463 * of the write error recovery mechanism for old OnStream
1464 * firmware revisions.
1465 * Precondition for this function to work: all frames in the
1466 * drive's buffer must be of one type (DATA, MARK or EOD)!
1467 */
1468static int osst_read_back_buffer_and_rewrite(struct osst_tape * STp, struct osst_request ** aSRpnt,
1469						unsigned int frame, unsigned int skip, int pending)
1470{
1471	struct osst_request   * SRpnt = * aSRpnt;
1472	unsigned char	      * buffer, * p;
1473	unsigned char		cmd[MAX_COMMAND_SIZE];
1474	int			flag, new_frame, i;
1475	int			nframes          = STp->cur_frames;
1476	int			blks_per_frame   = ntohs(STp->buffer->aux->dat.dat_list[0].blk_cnt);
1477	int			frame_seq_number = ntohl(STp->buffer->aux->frame_seq_num)
1478						- (nframes + pending - 1);
1479	int			logical_blk_num  = ntohl(STp->buffer->aux->logical_blk_num)
1480						- (nframes + pending - 1) * blks_per_frame;
1481	char		      * name             = tape_name(STp);
1482	unsigned long		startwait        = jiffies;
1483#if DEBUG
1484	int			dbg              = debugging;
1485#endif
1486
1487	if ((buffer = vmalloc((nframes + 1) * OS_DATA_SIZE)) == NULL)
1488		return (-EIO);
1489
1490	printk(KERN_INFO "%s:I: Reading back %d frames from drive buffer%s\n",
1491			 name, nframes, pending?" and one that was pending":"");
1492
1493	osst_copy_from_buffer(STp->buffer, (p = &buffer[nframes * OS_DATA_SIZE]));
1494#if DEBUG
1495	if (pending && debugging)
1496		printk(OSST_DEB_MSG "%s:D: Pending frame %d (lblk %d), data %02x %02x %02x %02x\n",
1497				name, frame_seq_number + nframes,
1498			       	logical_blk_num + nframes * blks_per_frame,
1499			       	p[0], p[1], p[2], p[3]);
1500#endif
1501	for (i = 0, p = buffer; i < nframes; i++, p += OS_DATA_SIZE) {
1502
1503		memset(cmd, 0, MAX_COMMAND_SIZE);
1504		cmd[0] = 0x3C;		/* Buffer Read           */
1505		cmd[1] = 6;		/* Retrieve Faulty Block */
1506		cmd[7] = 32768 >> 8;
1507		cmd[8] = 32768 & 0xff;
1508
1509		SRpnt = osst_do_scsi(SRpnt, STp, cmd, OS_FRAME_SIZE, DMA_FROM_DEVICE,
1510					    STp->timeout, MAX_RETRIES, 1);
1511
1512		if ((STp->buffer)->syscall_result || !SRpnt) {
1513			printk(KERN_ERR "%s:E: Failed to read frame back from OnStream buffer\n", name);
1514			vfree(buffer);
1515			*aSRpnt = SRpnt;
1516			return (-EIO);
1517		}
1518		osst_copy_from_buffer(STp->buffer, p);
1519#if DEBUG
1520		if (debugging)
1521			printk(OSST_DEB_MSG "%s:D: Read back logical frame %d, data %02x %02x %02x %02x\n",
1522					  name, frame_seq_number + i, p[0], p[1], p[2], p[3]);
1523#endif
1524	}
1525	*aSRpnt = SRpnt;
1526	osst_get_frame_position(STp, aSRpnt);
1527
1528#if DEBUG
1529	printk(OSST_DEB_MSG "%s:D: Frames left in buffer: %d\n", name, STp->cur_frames);
1530#endif
1531	/* Write synchronously so we can be sure we're OK again and don't have to recover recursively */
1532	/* In the header we don't actually re-write the frames that fail, just the ones after them */
1533
1534	for (flag=1, new_frame=frame, p=buffer, i=0; i < nframes + pending; ) {
1535
1536		if (flag) {
1537			if (STp->write_type == OS_WRITE_HEADER) {
1538				i += skip;
1539				p += skip * OS_DATA_SIZE;
1540			}
1541			else if (new_frame < 2990 && new_frame+skip+nframes+pending >= 2990)
1542				new_frame = 3000-i;
1543			else
1544				new_frame += skip;
1545#if DEBUG
1546			printk(OSST_DEB_MSG "%s:D: Position to frame %d, write fseq %d\n",
1547						name, new_frame+i, frame_seq_number+i);
1548#endif
1549			osst_set_frame_position(STp, aSRpnt, new_frame + i, 0);
1550			osst_wait_ready(STp, aSRpnt, 60, OSST_WAIT_POSITION_COMPLETE);
1551			osst_get_frame_position(STp, aSRpnt);
1552			SRpnt = * aSRpnt;
1553
1554			if (new_frame > frame + 1000) {
1555				printk(KERN_ERR "%s:E: Failed to find writable tape media\n", name);
1556				vfree(buffer);
1557				return (-EIO);
1558			}
1559			if ( i >= nframes + pending ) break;
1560			flag = 0;
1561		}
1562		osst_copy_to_buffer(STp->buffer, p);
1563		/*
1564		 * IMPORTANT: for error recovery to work, _never_ queue frames with mixed frame type!
1565		 */
1566		osst_init_aux(STp, STp->buffer->aux->frame_type, frame_seq_number+i,
1567			       	logical_blk_num + i*blks_per_frame,
1568			       	ntohl(STp->buffer->aux->dat.dat_list[0].blk_sz), blks_per_frame);
1569		memset(cmd, 0, MAX_COMMAND_SIZE);
1570		cmd[0] = WRITE_6;
1571		cmd[1] = 1;
1572		cmd[4] = 1;
1573
1574#if DEBUG
1575		if (debugging)
1576			printk(OSST_DEB_MSG
1577				"%s:D: About to write frame %d, seq %d, lbn %d, data %02x %02x %02x %02x\n",
1578				name, new_frame+i, frame_seq_number+i, logical_blk_num + i*blks_per_frame,
1579				p[0], p[1], p[2], p[3]);
1580#endif
1581		SRpnt = osst_do_scsi(SRpnt, STp, cmd, OS_FRAME_SIZE, DMA_TO_DEVICE,
1582					    STp->timeout, MAX_RETRIES, 1);
1583
1584		if (STp->buffer->syscall_result)
1585			flag = 1;
1586		else {
1587			p += OS_DATA_SIZE; i++;
1588
1589			/* if we just sent the last frame, wait till all successfully written */
1590			if ( i == nframes + pending ) {
1591#if DEBUG
1592				printk(OSST_DEB_MSG "%s:D: Check re-write successful\n", name);
1593#endif
1594				memset(cmd, 0, MAX_COMMAND_SIZE);
1595				cmd[0] = WRITE_FILEMARKS;
1596				cmd[1] = 1;
1597				SRpnt = osst_do_scsi(SRpnt, STp, cmd, 0, DMA_NONE,
1598							    STp->timeout, MAX_RETRIES, 1);
1599#if DEBUG
1600				if (debugging) {
1601					printk(OSST_DEB_MSG "%s:D: Sleeping in re-write wait ready\n", name);
1602					printk(OSST_DEB_MSG "%s:D: Turning off debugging for a while\n", name);
1603					debugging = 0;
1604				}
1605#endif
1606				flag = STp->buffer->syscall_result;
1607				while ( !flag && time_before(jiffies, startwait + 60*HZ) ) {
1608
1609					memset(cmd, 0, MAX_COMMAND_SIZE);
1610					cmd[0] = TEST_UNIT_READY;
1611
1612					SRpnt = osst_do_scsi(SRpnt, STp, cmd, 0, DMA_NONE, STp->timeout,
1613												MAX_RETRIES, 1);
1614
1615					if (SRpnt->sense[2] == 2 && SRpnt->sense[12] == 4 &&
1616					    (SRpnt->sense[13] == 1 || SRpnt->sense[13] == 8)) {
1617						/* in the process of becoming ready */
1618						msleep(100);
1619						continue;
1620					}
1621					if (STp->buffer->syscall_result)
1622						flag = 1;
1623					break;
1624				}
1625#if DEBUG
1626				debugging = dbg;
1627				printk(OSST_DEB_MSG "%s:D: Wait re-write finished\n", name);
1628#endif
1629			}
1630		}
1631		*aSRpnt = SRpnt;
1632		if (flag) {
1633			if ((SRpnt->sense[ 2] & 0x0f) == 13 &&
1634			     SRpnt->sense[12]         ==  0 &&
1635			     SRpnt->sense[13]         ==  2) {
1636				printk(KERN_ERR "%s:E: Volume overflow in write error recovery\n", name);
1637				vfree(buffer);
1638				return (-EIO);			/* hit end of tape = fail */
1639			}
1640			i = ((SRpnt->sense[3] << 24) |
1641			     (SRpnt->sense[4] << 16) |
1642			     (SRpnt->sense[5] <<  8) |
1643			      SRpnt->sense[6]        ) - new_frame;
1644			p = &buffer[i * OS_DATA_SIZE];
1645#if DEBUG
1646			printk(OSST_DEB_MSG "%s:D: Additional write error at %d\n", name, new_frame+i);
1647#endif
1648			osst_get_frame_position(STp, aSRpnt);
1649#if DEBUG
1650			printk(OSST_DEB_MSG "%s:D: reported frame positions: host = %d, tape = %d, buffer = %d\n",
1651					  name, STp->first_frame_position, STp->last_frame_position, STp->cur_frames);
1652#endif
1653		}
1654	}
1655	if (flag) {
1656		/* error recovery did not successfully complete */
1657		printk(KERN_ERR "%s:D: Write error recovery failed in %s\n", name,
1658				STp->write_type == OS_WRITE_HEADER?"header":"body");
1659	}
1660	if (!pending)
1661		osst_copy_to_buffer(STp->buffer, p);	/* so buffer content == at entry in all cases */
1662	vfree(buffer);
1663	return 0;
1664}
1665
1666static int osst_reposition_and_retry(struct osst_tape * STp, struct osst_request ** aSRpnt,
1667					unsigned int frame, unsigned int skip, int pending)
1668{
1669	unsigned char		cmd[MAX_COMMAND_SIZE];
1670	struct osst_request   * SRpnt;
1671	char		      * name      = tape_name(STp);
1672	int			expected  = 0;
1673	int			attempts  = 1000 / skip;
1674	int			flag      = 1;
1675	unsigned long		startwait = jiffies;
1676#if DEBUG
1677	int			dbg       = debugging;
1678#endif
1679
1680	while (attempts && time_before(jiffies, startwait + 60*HZ)) {
1681		if (flag) {
1682#if DEBUG
1683			debugging = dbg;
1684#endif
1685			if (frame < 2990 && frame+skip+STp->cur_frames+pending >= 2990)
1686				frame = 3000-skip;
1687			expected = frame+skip+STp->cur_frames+pending;
1688#if DEBUG
1689			printk(OSST_DEB_MSG "%s:D: Position to fppos %d, re-write from fseq %d\n",
1690					  name, frame+skip, STp->frame_seq_number-STp->cur_frames-pending);
1691#endif
1692			osst_set_frame_position(STp, aSRpnt, frame + skip, 1);
1693			flag = 0;
1694			attempts--;
1695			schedule_timeout_interruptible(msecs_to_jiffies(100));
1696		}
1697		if (osst_get_frame_position(STp, aSRpnt) < 0) {		/* additional write error */
1698#if DEBUG
1699			printk(OSST_DEB_MSG "%s:D: Addl error, host %d, tape %d, buffer %d\n",
1700					  name, STp->first_frame_position,
1701					  STp->last_frame_position, STp->cur_frames);
1702#endif
1703			frame = STp->last_frame_position;
1704			flag = 1;
1705			continue;
1706		}
1707		if (pending && STp->cur_frames < 50) {
1708
1709			memset(cmd, 0, MAX_COMMAND_SIZE);
1710			cmd[0] = WRITE_6;
1711			cmd[1] = 1;
1712			cmd[4] = 1;
1713#if DEBUG
1714			printk(OSST_DEB_MSG "%s:D: About to write pending fseq %d at fppos %d\n",
1715					  name, STp->frame_seq_number-1, STp->first_frame_position);
1716#endif
1717			SRpnt = osst_do_scsi(*aSRpnt, STp, cmd, OS_FRAME_SIZE, DMA_TO_DEVICE,
1718						      STp->timeout, MAX_RETRIES, 1);
1719			*aSRpnt = SRpnt;
1720
1721			if (STp->buffer->syscall_result) {		/* additional write error */
1722				if ((SRpnt->sense[ 2] & 0x0f) == 13 &&
1723				     SRpnt->sense[12]         ==  0 &&
1724				     SRpnt->sense[13]         ==  2) {
1725					printk(KERN_ERR
1726					       "%s:E: Volume overflow in write error recovery\n",
1727					       name);
1728					break;				/* hit end of tape = fail */
1729				}
1730				flag = 1;
1731			}
1732			else
1733				pending = 0;
1734
1735			continue;
1736		}
1737		if (STp->cur_frames == 0) {
1738#if DEBUG
1739			debugging = dbg;
1740			printk(OSST_DEB_MSG "%s:D: Wait re-write finished\n", name);
1741#endif
1742			if (STp->first_frame_position != expected) {
1743				printk(KERN_ERR "%s:A: Actual position %d - expected %d\n",
1744						name, STp->first_frame_position, expected);
1745				return (-EIO);
1746			}
1747			return 0;
1748		}
1749#if DEBUG
1750		if (debugging) {
1751			printk(OSST_DEB_MSG "%s:D: Sleeping in re-write wait ready\n", name);
1752			printk(OSST_DEB_MSG "%s:D: Turning off debugging for a while\n", name);
1753			debugging = 0;
1754		}
1755#endif
1756		schedule_timeout_interruptible(msecs_to_jiffies(100));
1757	}
1758	printk(KERN_ERR "%s:E: Failed to find valid tape media\n", name);
1759#if DEBUG
1760	debugging = dbg;
1761#endif
1762	return (-EIO);
1763}
1764
1765/*
1766 * Error recovery algorithm for the OnStream tape.
1767 */
1768
1769static int osst_write_error_recovery(struct osst_tape * STp, struct osst_request ** aSRpnt, int pending)
1770{
1771	struct osst_request * SRpnt  = * aSRpnt;
1772	struct st_partstat  * STps   = & STp->ps[STp->partition];
1773	char		    * name   = tape_name(STp);
1774	int		      retval = 0;
1775	int		      rw_state;
1776	unsigned int	      frame, skip;
1777
1778	rw_state = STps->rw;
1779
1780	if ((SRpnt->sense[ 2] & 0x0f) != 3
1781	  || SRpnt->sense[12]         != 12
1782	  || SRpnt->sense[13]         != 0) {
1783#if DEBUG
1784		printk(OSST_DEB_MSG "%s:D: Write error recovery cannot handle %02x:%02x:%02x\n", name,
1785			SRpnt->sense[2], SRpnt->sense[12], SRpnt->sense[13]);
1786#endif
1787		return (-EIO);
1788	}
1789	frame =	(SRpnt->sense[3] << 24) |
1790		(SRpnt->sense[4] << 16) |
1791		(SRpnt->sense[5] <<  8) |
1792		 SRpnt->sense[6];
1793	skip  =  SRpnt->sense[9];
1794
1795#if DEBUG
1796	printk(OSST_DEB_MSG "%s:D: Detected physical bad frame at %u, advised to skip %d\n", name, frame, skip);
1797#endif
1798	osst_get_frame_position(STp, aSRpnt);
1799#if DEBUG
1800	printk(OSST_DEB_MSG "%s:D: reported frame positions: host = %d, tape = %d\n",
1801			name, STp->first_frame_position, STp->last_frame_position);
1802#endif
1803	switch (STp->write_type) {
1804	   case OS_WRITE_DATA:
1805	   case OS_WRITE_EOD:
1806	   case OS_WRITE_NEW_MARK:
1807		printk(KERN_WARNING
1808			"%s:I: Relocating %d buffered logical frames from position %u to %u\n",
1809			name, STp->cur_frames, frame, (frame + skip > 3000 && frame < 3000)?3000:frame + skip);
1810		if (STp->os_fw_rev >= 10600)
1811			retval = osst_reposition_and_retry(STp, aSRpnt, frame, skip, pending);
1812		else
1813			retval = osst_read_back_buffer_and_rewrite(STp, aSRpnt, frame, skip, pending);
1814		printk(KERN_WARNING "%s:%s: %sWrite error%srecovered\n", name,
1815			       	retval?"E"    :"I",
1816			       	retval?""     :"Don't worry, ",
1817			       	retval?" not ":" ");
1818		break;
1819	   case OS_WRITE_LAST_MARK:
1820		printk(KERN_ERR "%s:E: Bad frame in update last marker, fatal\n", name);
1821		osst_set_frame_position(STp, aSRpnt, frame + STp->cur_frames + pending, 0);
1822		retval = -EIO;
1823		break;
1824	   case OS_WRITE_HEADER:
1825		printk(KERN_WARNING "%s:I: Bad frame in header partition, skipped\n", name);
1826		retval = osst_read_back_buffer_and_rewrite(STp, aSRpnt, frame, 1, pending);
1827		break;
1828	   default:
1829		printk(KERN_INFO "%s:I: Bad frame in filler, ignored\n", name);
1830		osst_set_frame_position(STp, aSRpnt, frame + STp->cur_frames + pending, 0);
1831	}
1832	osst_get_frame_position(STp, aSRpnt);
1833#if DEBUG
1834	printk(OSST_DEB_MSG "%s:D: Positioning complete, cur_frames %d, pos %d, tape pos %d\n",
1835			name, STp->cur_frames, STp->first_frame_position, STp->last_frame_position);
1836	printk(OSST_DEB_MSG "%s:D: next logical frame to write: %d\n", name, STp->logical_blk_num);
1837#endif
1838	if (retval == 0) {
1839		STp->recover_count++;
1840		STp->recover_erreg++;
1841	} else
1842		STp->abort_count++;
1843
1844	STps->rw = rw_state;
1845	return retval;
1846}
1847
1848static int osst_space_over_filemarks_backward(struct osst_tape * STp, struct osst_request ** aSRpnt,
1849								 int mt_op, int mt_count)
1850{
1851	char  * name = tape_name(STp);
1852	int     cnt;
1853	int     last_mark_ppos = -1;
1854
1855#if DEBUG
1856	printk(OSST_DEB_MSG "%s:D: Reached space_over_filemarks_backwards %d %d\n", name, mt_op, mt_count);
1857#endif
1858	if (osst_get_logical_frame(STp, aSRpnt, -1, 0) < 0) {
1859#if DEBUG
1860		printk(OSST_DEB_MSG "%s:D: Couldn't get logical blk num in space_filemarks_bwd\n", name);
1861#endif
1862		return -EIO;
1863	}
1864	if (STp->linux_media_version >= 4) {
1865		/*
1866		 * direct lookup in header filemark list
1867		 */
1868		cnt = ntohl(STp->buffer->aux->filemark_cnt);
1869		if (STp->header_ok                         &&
1870		    STp->header_cache != NULL              &&
1871		    (cnt - mt_count)  >= 0                 &&
1872		    (cnt - mt_count)   < OS_FM_TAB_MAX     &&
1873		    (cnt - mt_count)   < STp->filemark_cnt &&
1874		    STp->header_cache->dat_fm_tab.fm_tab_ent[cnt-1] == STp->buffer->aux->last_mark_ppos)
1875
1876			last_mark_ppos = ntohl(STp->header_cache->dat_fm_tab.fm_tab_ent[cnt - mt_count]);
1877#if DEBUG
1878		if (STp->header_cache == NULL || (cnt - mt_count) < 0 || (cnt - mt_count) >= OS_FM_TAB_MAX)
1879			printk(OSST_DEB_MSG "%s:D: Filemark lookup fail due to %s\n", name,
1880			       STp->header_cache == NULL?"lack of header cache":"count out of range");
1881		else
1882			printk(OSST_DEB_MSG "%s:D: Filemark lookup: prev mark %d (%s), skip %d to %d\n",
1883				name, cnt,
1884				((cnt == -1 && ntohl(STp->buffer->aux->last_mark_ppos) == -1) ||
1885				 (STp->header_cache->dat_fm_tab.fm_tab_ent[cnt-1] ==
1886					 STp->buffer->aux->last_mark_ppos))?"match":"error",
1887			       mt_count, last_mark_ppos);
1888#endif
1889		if (last_mark_ppos > 10 && last_mark_ppos < STp->eod_frame_ppos) {
1890			osst_position_tape_and_confirm(STp, aSRpnt, last_mark_ppos);
1891			if (osst_get_logical_frame(STp, aSRpnt, -1, 0) < 0) {
1892#if DEBUG
1893				printk(OSST_DEB_MSG
1894					"%s:D: Couldn't get logical blk num in space_filemarks\n", name);
1895#endif
1896				return (-EIO);
1897			}
1898			if (STp->buffer->aux->frame_type != OS_FRAME_TYPE_MARKER) {
1899				printk(KERN_WARNING "%s:W: Expected to find marker at ppos %d, not found\n",
1900						 name, last_mark_ppos);
1901				return (-EIO);
1902			}
1903			goto found;
1904		}
1905#if DEBUG
1906		printk(OSST_DEB_MSG "%s:D: Reverting to scan filemark backwards\n", name);
1907#endif
1908	}
1909	cnt = 0;
1910	while (cnt != mt_count) {
1911		last_mark_ppos = ntohl(STp->buffer->aux->last_mark_ppos);
1912		if (last_mark_ppos == -1)
1913			return (-EIO);
1914#if DEBUG
1915		printk(OSST_DEB_MSG "%s:D: Positioning to last mark at %d\n", name, last_mark_ppos);
1916#endif
1917		osst_position_tape_and_confirm(STp, aSRpnt, last_mark_ppos);
1918		cnt++;
1919		if (osst_get_logical_frame(STp, aSRpnt, -1, 0) < 0) {
1920#if DEBUG
1921			printk(OSST_DEB_MSG "%s:D: Couldn't get logical blk num in space_filemarks\n", name);
1922#endif
1923			return (-EIO);
1924		}
1925		if (STp->buffer->aux->frame_type != OS_FRAME_TYPE_MARKER) {
1926			printk(KERN_WARNING "%s:W: Expected to find marker at ppos %d, not found\n",
1927					 name, last_mark_ppos);
1928			return (-EIO);
1929		}
1930	}
1931found:
1932	if (mt_op == MTBSFM) {
1933		STp->frame_seq_number++;
1934		STp->frame_in_buffer      = 0;
1935		STp->buffer->buffer_bytes = 0;
1936		STp->buffer->read_pointer = 0;
1937		STp->logical_blk_num     += ntohs(STp->buffer->aux->dat.dat_list[0].blk_cnt);
1938	}
1939	return 0;
1940}
1941
1942/*
1943 * ADRL 1.1 compatible "slow" space filemarks fwd version
1944 *
1945 * Just scans for the filemark sequentially.
1946 */
1947static int osst_space_over_filemarks_forward_slow(struct osst_tape * STp, struct osst_request ** aSRpnt,
1948								     int mt_op, int mt_count)
1949{
1950	int	cnt = 0;
1951#if DEBUG
1952	char  * name = tape_name(STp);
1953
1954	printk(OSST_DEB_MSG "%s:D: Reached space_over_filemarks_forward_slow %d %d\n", name, mt_op, mt_count);
1955#endif
1956	if (osst_get_logical_frame(STp, aSRpnt, -1, 0) < 0) {
1957#if DEBUG
1958		printk(OSST_DEB_MSG "%s:D: Couldn't get logical blk num in space_filemarks_fwd\n", name);
1959#endif
1960		return (-EIO);
1961	}
1962	while (1) {
1963		if (osst_get_logical_frame(STp, aSRpnt, -1, 0) < 0) {
1964#if DEBUG
1965			printk(OSST_DEB_MSG "%s:D: Couldn't get logical blk num in space_filemarks\n", name);
1966#endif
1967			return (-EIO);
1968		}
1969		if (STp->buffer->aux->frame_type == OS_FRAME_TYPE_MARKER)
1970			cnt++;
1971		if (STp->buffer->aux->frame_type == OS_FRAME_TYPE_EOD) {
1972#if DEBUG
1973			printk(OSST_DEB_MSG "%s:D: space_fwd: EOD reached\n", name);
1974#endif
1975			if (STp->first_frame_position > STp->eod_frame_ppos+1) {
1976#if DEBUG
1977				printk(OSST_DEB_MSG "%s:D: EOD position corrected (%d=>%d)\n",
1978					       	name, STp->eod_frame_ppos, STp->first_frame_position-1);
1979#endif
1980				STp->eod_frame_ppos = STp->first_frame_position-1;
1981			}
1982			return (-EIO);
1983		}
1984		if (cnt == mt_count)
1985			break;
1986		STp->frame_in_buffer = 0;
1987	}
1988	if (mt_op == MTFSF) {
1989		STp->frame_seq_number++;
1990		STp->frame_in_buffer      = 0;
1991		STp->buffer->buffer_bytes = 0;
1992		STp->buffer->read_pointer = 0;
1993		STp->logical_blk_num     += ntohs(STp->buffer->aux->dat.dat_list[0].blk_cnt);
1994	}
1995	return 0;
1996}
1997
1998/*
1999 * Fast linux specific version of OnStream FSF
2000 */
2001static int osst_space_over_filemarks_forward_fast(struct osst_tape * STp, struct osst_request ** aSRpnt,
2002								     int mt_op, int mt_count)
2003{
2004	char  * name = tape_name(STp);
2005	int	cnt  = 0,
2006		next_mark_ppos = -1;
2007
2008#if DEBUG
2009	printk(OSST_DEB_MSG "%s:D: Reached space_over_filemarks_forward_fast %d %d\n", name, mt_op, mt_count);
2010#endif
2011	if (osst_get_logical_frame(STp, aSRpnt, -1, 0) < 0) {
2012#if DEBUG
2013		printk(OSST_DEB_MSG "%s:D: Couldn't get logical blk num in space_filemarks_fwd\n", name);
2014#endif
2015		return (-EIO);
2016	}
2017
2018	if (STp->linux_media_version >= 4) {
2019		/*
2020		 * direct lookup in header filemark list
2021		 */
2022		cnt = ntohl(STp->buffer->aux->filemark_cnt) - 1;
2023		if (STp->header_ok                         &&
2024		    STp->header_cache != NULL              &&
2025		    (cnt + mt_count)   < OS_FM_TAB_MAX     &&
2026		    (cnt + mt_count)   < STp->filemark_cnt &&
2027		    ((cnt == -1 && ntohl(STp->buffer->aux->last_mark_ppos) == -1) ||
2028		     (STp->header_cache->dat_fm_tab.fm_tab_ent[cnt] == STp->buffer->aux->last_mark_ppos)))
2029
2030			next_mark_ppos = ntohl(STp->header_cache->dat_fm_tab.fm_tab_ent[cnt + mt_count]);
2031#if DEBUG
2032		if (STp->header_cache == NULL || (cnt + mt_count) >= OS_FM_TAB_MAX)
2033			printk(OSST_DEB_MSG "%s:D: Filemark lookup fail due to %s\n", name,
2034			       STp->header_cache == NULL?"lack of header cache":"count out of range");
2035		else
2036			printk(OSST_DEB_MSG "%s:D: Filemark lookup: prev mark %d (%s), skip %d to %d\n",
2037			       name, cnt,
2038			       ((cnt == -1 && ntohl(STp->buffer->aux->last_mark_ppos) == -1) ||
2039				(STp->header_cache->dat_fm_tab.fm_tab_ent[cnt] ==
2040					 STp->buffer->aux->last_mark_ppos))?"match":"error",
2041			       mt_count, next_mark_ppos);
2042#endif
2043		if (next_mark_ppos <= 10 || next_mark_ppos > STp->eod_frame_ppos) {
2044#if DEBUG
2045			printk(OSST_DEB_MSG "%s:D: Reverting to slow filemark space\n", name);
2046#endif
2047			return osst_space_over_filemarks_forward_slow(STp, aSRpnt, mt_op, mt_count);
2048		} else {
2049			osst_position_tape_and_confirm(STp, aSRpnt, next_mark_ppos);
2050			if (osst_get_logical_frame(STp, aSRpnt, -1, 0) < 0) {
2051#if DEBUG
2052				printk(OSST_DEB_MSG "%s:D: Couldn't get logical blk num in space_filemarks\n",
2053						 name);
2054#endif
2055				return (-EIO);
2056			}
2057			if (STp->buffer->aux->frame_type != OS_FRAME_TYPE_MARKER) {
2058				printk(KERN_WARNING "%s:W: Expected to find marker at ppos %d, not found\n",
2059						 name, next_mark_ppos);
2060				return (-EIO);
2061			}
2062			if (ntohl(STp->buffer->aux->filemark_cnt) != cnt + mt_count) {
2063				printk(KERN_WARNING "%s:W: Expected to find marker %d at ppos %d, not %d\n",
2064						 name, cnt+mt_count, next_mark_ppos,
2065						 ntohl(STp->buffer->aux->filemark_cnt));
2066       				return (-EIO);
2067			}
2068		}
2069	} else {
2070		/*
2071		 * Find nearest (usually previous) marker, then jump from marker to marker
2072		 */
2073		while (1) {
2074			if (STp->buffer->aux->frame_type == OS_FRAME_TYPE_MARKER)
2075				break;
2076			if (STp->buffer->aux->frame_type == OS_FRAME_TYPE_EOD) {
2077#if DEBUG
2078				printk(OSST_DEB_MSG "%s:D: space_fwd: EOD reached\n", name);
2079#endif
2080				return (-EIO);
2081			}
2082			if (ntohl(STp->buffer->aux->filemark_cnt) == 0) {
2083				if (STp->first_mark_ppos == -1) {
2084#if DEBUG
2085					printk(OSST_DEB_MSG "%s:D: Reverting to slow filemark space\n", name);
2086#endif
2087					return osst_space_over_filemarks_forward_slow(STp, aSRpnt, mt_op, mt_count);
2088				}
2089				osst_position_tape_and_confirm(STp, aSRpnt, STp->first_mark_ppos);
2090				if (osst_get_logical_frame(STp, aSRpnt, -1, 0) < 0) {
2091#if DEBUG
2092					printk(OSST_DEB_MSG
2093					       "%s:D: Couldn't get logical blk num in space_filemarks_fwd_fast\n",
2094					       name);
2095#endif
2096					return (-EIO);
2097				}
2098				if (STp->buffer->aux->frame_type != OS_FRAME_TYPE_MARKER) {
2099					printk(KERN_WARNING "%s:W: Expected to find filemark at %d\n",
2100							 name, STp->first_mark_ppos);
2101					return (-EIO);
2102				}
2103			} else {
2104				if (osst_space_over_filemarks_backward(STp, aSRpnt, MTBSF, 1) < 0)
2105					return (-EIO);
2106				mt_count++;
2107			}
2108		}
2109		cnt++;
2110		while (cnt != mt_count) {
2111			next_mark_ppos = ntohl(STp->buffer->aux->next_mark_ppos);
2112			if (!next_mark_ppos || next_mark_ppos > STp->eod_frame_ppos) {
2113#if DEBUG
2114				printk(OSST_DEB_MSG "%s:D: Reverting to slow filemark space\n", name);
2115#endif
2116				return osst_space_over_filemarks_forward_slow(STp, aSRpnt, mt_op, mt_count - cnt);
2117			}
2118#if DEBUG
2119			else printk(OSST_DEB_MSG "%s:D: Positioning to next mark at %d\n", name, next_mark_ppos);
2120#endif
2121			osst_position_tape_and_confirm(STp, aSRpnt, next_mark_ppos);
2122			cnt++;
2123			if (osst_get_logical_frame(STp, aSRpnt, -1, 0) < 0) {
2124#if DEBUG
2125				printk(OSST_DEB_MSG "%s:D: Couldn't get logical blk num in space_filemarks\n",
2126						 name);
2127#endif
2128				return (-EIO);
2129			}
2130			if (STp->buffer->aux->frame_type != OS_FRAME_TYPE_MARKER) {
2131				printk(KERN_WARNING "%s:W: Expected to find marker at ppos %d, not found\n",
2132						 name, next_mark_ppos);
2133				return (-EIO);
2134			}
2135		}
2136	}
2137	if (mt_op == MTFSF) {
2138		STp->frame_seq_number++;
2139		STp->frame_in_buffer      = 0;
2140		STp->buffer->buffer_bytes = 0;
2141		STp->buffer->read_pointer = 0;
2142		STp->logical_blk_num     += ntohs(STp->buffer->aux->dat.dat_list[0].blk_cnt);
2143	}
2144	return 0;
2145}
2146
2147/*
2148 * In debug mode, we want to see as many errors as possible
2149 * to test the error recovery mechanism.
2150 */
2151#if DEBUG
2152static void osst_set_retries(struct osst_tape * STp, struct osst_request ** aSRpnt, int retries)
2153{
2154	unsigned char		cmd[MAX_COMMAND_SIZE];
2155	struct osst_request   * SRpnt  = * aSRpnt;
2156	char		      * name   = tape_name(STp);
2157
2158	memset(cmd, 0, MAX_COMMAND_SIZE);
2159	cmd[0] = MODE_SELECT;
2160	cmd[1] = 0x10;
2161	cmd[4] = NUMBER_RETRIES_PAGE_LENGTH + MODE_HEADER_LENGTH;
2162
2163	(STp->buffer)->b_data[0] = cmd[4] - 1;
2164	(STp->buffer)->b_data[1] = 0;			/* Medium Type - ignoring */
2165	(STp->buffer)->b_data[2] = 0;			/* Reserved */
2166	(STp->buffer)->b_data[3] = 0;			/* Block Descriptor Length */
2167	(STp->buffer)->b_data[MODE_HEADER_LENGTH + 0] = NUMBER_RETRIES_PAGE | (1 << 7);
2168	(STp->buffer)->b_data[MODE_HEADER_LENGTH + 1] = 2;
2169	(STp->buffer)->b_data[MODE_HEADER_LENGTH + 2] = 4;
2170	(STp->buffer)->b_data[MODE_HEADER_LENGTH + 3] = retries;
2171
2172	if (debugging)
2173	    printk(OSST_DEB_MSG "%s:D: Setting number of retries on OnStream tape to %d\n", name, retries);
2174
2175	SRpnt = osst_do_scsi(SRpnt, STp, cmd, cmd[4], DMA_TO_DEVICE, STp->timeout, 0, 1);
2176	*aSRpnt = SRpnt;
2177
2178	if ((STp->buffer)->syscall_result)
2179	    printk (KERN_ERR "%s:D: Couldn't set retries to %d\n", name, retries);
2180}
2181#endif
2182
2183
2184static int osst_write_filemark(struct osst_tape * STp, struct osst_request ** aSRpnt)
2185{
2186	int	result;
2187	int	this_mark_ppos = STp->first_frame_position;
2188	int	this_mark_lbn  = STp->logical_blk_num;
2189#if DEBUG
2190	char  * name = tape_name(STp);
2191#endif
2192
2193	if (STp->raw) return 0;
2194
2195	STp->write_type = OS_WRITE_NEW_MARK;
2196#if DEBUG
2197	printk(OSST_DEB_MSG "%s:D: Writing Filemark %i at fppos %d (fseq %d, lblk %d)\n",
2198	       name, STp->filemark_cnt, this_mark_ppos, STp->frame_seq_number, this_mark_lbn);
2199#endif
2200	STp->dirty = 1;
2201	result  = osst_flush_write_buffer(STp, aSRpnt);
2202	result |= osst_flush_drive_buffer(STp, aSRpnt);
2203	STp->last_mark_ppos = this_mark_ppos;
2204	STp->last_mark_lbn  = this_mark_lbn;
2205	if (STp->header_cache != NULL && STp->filemark_cnt < OS_FM_TAB_MAX)
2206		STp->header_cache->dat_fm_tab.fm_tab_ent[STp->filemark_cnt] = htonl(this_mark_ppos);
2207	if (STp->filemark_cnt++ == 0)
2208		STp->first_mark_ppos = this_mark_ppos;
2209	return result;
2210}
2211
2212static int osst_write_eod(struct osst_tape * STp, struct osst_request ** aSRpnt)
2213{
2214	int	result;
2215#if DEBUG
2216	char  * name = tape_name(STp);
2217#endif
2218
2219	if (STp->raw) return 0;
2220
2221	STp->write_type = OS_WRITE_EOD;
2222	STp->eod_frame_ppos = STp->first_frame_position;
2223#if DEBUG
2224	printk(OSST_DEB_MSG "%s:D: Writing EOD at fppos %d (fseq %d, lblk %d)\n", name,
2225			STp->eod_frame_ppos, STp->frame_seq_number, STp->logical_blk_num);
2226#endif
2227	STp->dirty = 1;
2228
2229	result  = osst_flush_write_buffer(STp, aSRpnt);
2230	result |= osst_flush_drive_buffer(STp, aSRpnt);
2231	STp->eod_frame_lfa = --(STp->frame_seq_number);
2232	return result;
2233}
2234
2235static int osst_write_filler(struct osst_tape * STp, struct osst_request ** aSRpnt, int where, int count)
2236{
2237	char * name = tape_name(STp);
2238
2239#if DEBUG
2240	printk(OSST_DEB_MSG "%s:D: Reached onstream write filler group %d\n", name, where);
2241#endif
2242	osst_wait_ready(STp, aSRpnt, 60 * 5, 0);
2243	osst_set_frame_position(STp, aSRpnt, where, 0);
2244	STp->write_type = OS_WRITE_FILLER;
2245	while (count--) {
2246		memcpy(STp->buffer->b_data, "Filler", 6);
2247		STp->buffer->buffer_bytes = 6;
2248		STp->dirty = 1;
2249		if (osst_flush_write_buffer(STp, aSRpnt)) {
2250			printk(KERN_INFO "%s:I: Couldn't write filler frame\n", name);
2251			return (-EIO);
2252		}
2253	}
2254#if DEBUG
2255	printk(OSST_DEB_MSG "%s:D: Exiting onstream write filler group\n", name);
2256#endif
2257	return osst_flush_drive_buffer(STp, aSRpnt);
2258}
2259
2260static int __osst_write_header(struct osst_tape * STp, struct osst_request ** aSRpnt, int where, int count)
2261{
2262	char * name = tape_name(STp);
2263	int     result;
2264
2265#if DEBUG
2266	printk(OSST_DEB_MSG "%s:D: Reached onstream write header group %d\n", name, where);
2267#endif
2268	osst_wait_ready(STp, aSRpnt, 60 * 5, 0);
2269	osst_set_frame_position(STp, aSRpnt, where, 0);
2270	STp->write_type = OS_WRITE_HEADER;
2271	while (count--) {
2272		osst_copy_to_buffer(STp->buffer, (unsigned char *)STp->header_cache);
2273		STp->buffer->buffer_bytes = sizeof(os_header_t);
2274		STp->dirty = 1;
2275		if (osst_flush_write_buffer(STp, aSRpnt)) {
2276			printk(KERN_INFO "%s:I: Couldn't write header frame\n", name);
2277			return (-EIO);
2278		}
2279	}
2280	result = osst_flush_drive_buffer(STp, aSRpnt);
2281#if DEBUG
2282	printk(OSST_DEB_MSG "%s:D: Write onstream header group %s\n", name, result?"failed":"done");
2283#endif
2284	return result;
2285}
2286
2287static int osst_write_header(struct osst_tape * STp, struct osst_request ** aSRpnt, int locate_eod)
2288{
2289	os_header_t * header;
2290	int	      result;
2291	char        * name = tape_name(STp);
2292
2293#if DEBUG
2294	printk(OSST_DEB_MSG "%s:D: Writing tape header\n", name);
2295#endif
2296	if (STp->raw) return 0;
2297
2298	if (STp->header_cache == NULL) {
2299		if ((STp->header_cache = vmalloc(sizeof(os_header_t))) == NULL) {
2300			printk(KERN_ERR "%s:E: Failed to allocate header cache\n", name);
2301			return (-ENOMEM);
2302		}
2303		memset(STp->header_cache, 0, sizeof(os_header_t));
2304#if DEBUG
2305		printk(OSST_DEB_MSG "%s:D: Allocated and cleared memory for header cache\n", name);
2306#endif
2307	}
2308	if (STp->header_ok) STp->update_frame_cntr++;
2309	else                STp->update_frame_cntr = 0;
2310
2311	header = STp->header_cache;
2312	strcpy(header->ident_str, "ADR_SEQ");
2313	header->major_rev      = 1;
2314	header->minor_rev      = 4;
2315	header->ext_trk_tb_off = htons(17192);
2316	header->pt_par_num     = 1;
2317	header->partition[0].partition_num              = OS_DATA_PARTITION;
2318	header->partition[0].par_desc_ver               = OS_PARTITION_VERSION;
2319	header->partition[0].wrt_pass_cntr              = htons(STp->wrt_pass_cntr);
2320	header->partition[0].first_frame_ppos           = htonl(STp->first_data_ppos);
2321	header->partition[0].last_frame_ppos            = htonl(STp->capacity);
2322	header->partition[0].eod_frame_ppos             = htonl(STp->eod_frame_ppos);
2323	header->cfg_col_width                           = htonl(20);
2324	header->dat_col_width                           = htonl(1500);
2325	header->qfa_col_width                           = htonl(0);
2326	header->ext_track_tb.nr_stream_part             = 1;
2327	header->ext_track_tb.et_ent_sz                  = 32;
2328	header->ext_track_tb.dat_ext_trk_ey.et_part_num = 0;
2329	header->ext_track_tb.dat_ext_trk_ey.fmt         = 1;
2330	header->ext_track_tb.dat_ext_trk_ey.fm_tab_off  = htons(17736);
2331	header->ext_track_tb.dat_ext_trk_ey.last_hlb_hi = 0;
2332	header->ext_track_tb.dat_ext_trk_ey.last_hlb    = htonl(STp->eod_frame_lfa);
2333	header->ext_track_tb.dat_ext_trk_ey.last_pp	= htonl(STp->eod_frame_ppos);
2334	header->dat_fm_tab.fm_part_num                  = 0;
2335	header->dat_fm_tab.fm_tab_ent_sz                = 4;
2336	header->dat_fm_tab.fm_tab_ent_cnt               = htons(STp->filemark_cnt<OS_FM_TAB_MAX?
2337								STp->filemark_cnt:OS_FM_TAB_MAX);
2338
2339	result  = __osst_write_header(STp, aSRpnt, 0xbae, 5);
2340	if (STp->update_frame_cntr == 0)
2341		    osst_write_filler(STp, aSRpnt, 0xbb3, 5);
2342	result &= __osst_write_header(STp, aSRpnt,     5, 5);
2343
2344	if (locate_eod) {
2345#if DEBUG
2346		printk(OSST_DEB_MSG "%s:D: Locating back to eod frame addr %d\n", name, STp->eod_frame_ppos);
2347#endif
2348		osst_set_frame_position(STp, aSRpnt, STp->eod_frame_ppos, 0);
2349	}
2350	if (result)
2351		printk(KERN_ERR "%s:E: Write header failed\n", name);
2352	else {
2353		memcpy(STp->application_sig, "LIN4", 4);
2354		STp->linux_media         = 1;
2355		STp->linux_media_version = 4;
2356		STp->header_ok           = 1;
2357	}
2358	return result;
2359}
2360
2361static int osst_reset_header(struct osst_tape * STp, struct osst_request ** aSRpnt)
2362{
2363	if (STp->header_cache != NULL)
2364		memset(STp->header_cache, 0, sizeof(os_header_t));
2365
2366	STp->logical_blk_num = STp->frame_seq_number = 0;
2367	STp->frame_in_buffer = 0;
2368	STp->eod_frame_ppos = STp->first_data_ppos = 0x0000000A;
2369	STp->filemark_cnt = 0;
2370	STp->first_mark_ppos = STp->last_mark_ppos = STp->last_mark_lbn = -1;
2371	return osst_write_header(STp, aSRpnt, 1);
2372}
2373
2374static int __osst_analyze_headers(struct osst_tape * STp, struct osst_request ** aSRpnt, int ppos)
2375{
2376	char        * name = tape_name(STp);
2377	os_header_t * header;
2378	os_aux_t    * aux;
2379	char          id_string[8];
2380	int	      linux_media_version,
2381		      update_frame_cntr;
2382
2383	if (STp->raw)
2384		return 1;
2385
2386	if (ppos == 5 || ppos == 0xbae || STp->buffer->syscall_result) {
2387		if (osst_set_frame_position(STp, aSRpnt, ppos, 0))
2388			printk(KERN_WARNING "%s:W: Couldn't position tape\n", name);
2389		osst_wait_ready(STp, aSRpnt, 60 * 15, 0);
2390		if (osst_initiate_read (STp, aSRpnt)) {
2391			printk(KERN_WARNING "%s:W: Couldn't initiate read\n", name);
2392			return 0;
2393		}
2394	}
2395	if (osst_read_frame(STp, aSRpnt, 180)) {
2396#if DEBUG
2397		printk(OSST_DEB_MSG "%s:D: Couldn't read header frame\n", name);
2398#endif
2399		return 0;
2400	}
2401	header = (os_header_t *) STp->buffer->b_data;	/* warning: only first segment addressable */
2402	aux = STp->buffer->aux;
2403	if (aux->frame_type != OS_FRAME_TYPE_HEADER) {
2404#if DEBUG
2405		printk(OSST_DEB_MSG "%s:D: Skipping non-header frame (%d)\n", name, ppos);
2406#endif
2407		return 0;
2408	}
2409	if (ntohl(aux->frame_seq_num)              != 0                   ||
2410	    ntohl(aux->logical_blk_num)            != 0                   ||
2411	          aux->partition.partition_num     != OS_CONFIG_PARTITION ||
2412	    ntohl(aux->partition.first_frame_ppos) != 0                   ||
2413	    ntohl(aux->partition.last_frame_ppos)  != 0xbb7               ) {
2414#if DEBUG
2415		printk(OSST_DEB_MSG "%s:D: Invalid header frame (%d,%d,%d,%d,%d)\n", name,
2416				ntohl(aux->frame_seq_num), ntohl(aux->logical_blk_num),
2417			       	aux->partition.partition_num, ntohl(aux->partition.first_frame_ppos),
2418			       	ntohl(aux->partition.last_frame_ppos));
2419#endif
2420		return 0;
2421	}
2422	if (strncmp(header->ident_str, "ADR_SEQ", 7) != 0 &&
2423	    strncmp(header->ident_str, "ADR-SEQ", 7) != 0) {
2424		strlcpy(id_string, header->ident_str, 8);
2425#if DEBUG
2426		printk(OSST_DEB_MSG "%s:D: Invalid header identification string %s\n", name, id_string);
2427#endif
2428		return 0;
2429	}
2430	update_frame_cntr = ntohl(aux->update_frame_cntr);
2431	if (update_frame_cntr < STp->update_frame_cntr) {
2432#if DEBUG
2433		printk(OSST_DEB_MSG "%s:D: Skipping frame %d with update_frame_counter %d<%d\n",
2434				   name, ppos, update_frame_cntr, STp->update_frame_cntr);
2435#endif
2436		return 0;
2437	}
2438	if (header->major_rev != 1 || header->minor_rev != 4 ) {
2439#if DEBUG
2440		printk(OSST_DEB_MSG "%s:D: %s revision %d.%d detected (1.4 supported)\n",
2441				 name, (header->major_rev != 1 || header->minor_rev < 2 ||
2442				       header->minor_rev  > 4 )? "Invalid" : "Warning:",
2443				 header->major_rev, header->minor_rev);
2444#endif
2445		if (header->major_rev != 1 || header->minor_rev < 2 || header->minor_rev > 4)
2446			return 0;
2447	}
2448#if DEBUG
2449	if (header->pt_par_num != 1)
2450		printk(KERN_INFO "%s:W: %d partitions defined, only one supported\n",
2451				 name, header->pt_par_num);
2452#endif
2453	memcpy(id_string, aux->application_sig, 4);
2454	id_string[4] = 0;
2455	if (memcmp(id_string, "LIN", 3) == 0) {
2456		STp->linux_media = 1;
2457		linux_media_version = id_string[3] - '0';
2458		if (linux_media_version != 4)
2459			printk(KERN_INFO "%s:I: Linux media version %d detected (current 4)\n",
2460					 name, linux_media_version);
2461	} else {
2462		printk(KERN_WARNING "%s:W: Non Linux media detected (%s)\n", name, id_string);
2463		return 0;
2464	}
2465	if (linux_media_version < STp->linux_media_version) {
2466#if DEBUG
2467		printk(OSST_DEB_MSG "%s:D: Skipping frame %d with linux_media_version %d\n",
2468				  name, ppos, linux_media_version);
2469#endif
2470		return 0;
2471	}
2472	if (linux_media_version > STp->linux_media_version) {
2473#if DEBUG
2474		printk(OSST_DEB_MSG "%s:D: Frame %d sets linux_media_version to %d\n",
2475				   name, ppos, linux_media_version);
2476#endif
2477		memcpy(STp->application_sig, id_string, 5);
2478		STp->linux_media_version = linux_media_version;
2479		STp->update_frame_cntr = -1;
2480	}
2481	if (update_frame_cntr > STp->update_frame_cntr) {
2482#if DEBUG
2483		printk(OSST_DEB_MSG "%s:D: Frame %d sets update_frame_counter to %d\n",
2484				   name, ppos, update_frame_cntr);
2485#endif
2486		if (STp->header_cache == NULL) {
2487			if ((STp->header_cache = vmalloc(sizeof(os_header_t))) == NULL) {
2488				printk(KERN_ERR "%s:E: Failed to allocate header cache\n", name);
2489				return 0;
2490			}
2491#if DEBUG
2492			printk(OSST_DEB_MSG "%s:D: Allocated memory for header cache\n", name);
2493#endif
2494		}
2495		osst_copy_from_buffer(STp->buffer, (unsigned char *)STp->header_cache);
2496		header = STp->header_cache;	/* further accesses from cached (full) copy */
2497
2498		STp->wrt_pass_cntr     = ntohs(header->partition[0].wrt_pass_cntr);
2499		STp->first_data_ppos   = ntohl(header->partition[0].first_frame_ppos);
2500		STp->eod_frame_ppos    = ntohl(header->partition[0].eod_frame_ppos);
2501		STp->eod_frame_lfa     = ntohl(header->ext_track_tb.dat_ext_trk_ey.last_hlb);
2502		STp->filemark_cnt      = ntohl(aux->filemark_cnt);
2503		STp->first_mark_ppos   = ntohl(aux->next_mark_ppos);
2504		STp->last_mark_ppos    = ntohl(aux->last_mark_ppos);
2505		STp->last_mark_lbn     = ntohl(aux->last_mark_lbn);
2506		STp->update_frame_cntr = update_frame_cntr;
2507#if DEBUG
2508	printk(OSST_DEB_MSG "%s:D: Detected write pass %d, update frame counter %d, filemark counter %d\n",
2509			  name, STp->wrt_pass_cntr, STp->update_frame_cntr, STp->filemark_cnt);
2510	printk(OSST_DEB_MSG "%s:D: first data frame on tape = %d, last = %d, eod frame = %d\n", name,
2511			  STp->first_data_ppos,
2512			  ntohl(header->partition[0].last_frame_ppos),
2513			  ntohl(header->partition[0].eod_frame_ppos));
2514	printk(OSST_DEB_MSG "%s:D: first mark on tape = %d, last = %d, eod frame = %d\n",
2515			  name, STp->first_mark_ppos, STp->last_mark_ppos, STp->eod_frame_ppos);
2516#endif
2517		if (header->minor_rev < 4 && STp->linux_media_version == 4) {
2518#if DEBUG
2519			printk(OSST_DEB_MSG "%s:D: Moving filemark list to ADR 1.4 location\n", name);
2520#endif
2521			memcpy((void *)header->dat_fm_tab.fm_tab_ent,
2522			       (void *)header->old_filemark_list, sizeof(header->dat_fm_tab.fm_tab_ent));
2523			memset((void *)header->old_filemark_list, 0, sizeof(header->old_filemark_list));
2524		}
2525		if (header->minor_rev == 4   &&
2526		    (header->ext_trk_tb_off                          != htons(17192)               ||
2527		     header->partition[0].partition_num              != OS_DATA_PARTITION          ||
2528		     header->partition[0].par_desc_ver               != OS_PARTITION_VERSION       ||
2529		     header->partition[0].last_frame_ppos            != htonl(STp->capacity)       ||
2530		     header->cfg_col_width                           != htonl(20)                  ||
2531		     header->dat_col_width                           != htonl(1500)                ||
2532		     header->qfa_col_width                           != htonl(0)                   ||
2533		     header->ext_track_tb.nr_stream_part             != 1                          ||
2534		     header->ext_track_tb.et_ent_sz                  != 32                         ||
2535		     header->ext_track_tb.dat_ext_trk_ey.et_part_num != OS_DATA_PARTITION          ||
2536		     header->ext_track_tb.dat_ext_trk_ey.fmt         != 1                          ||
2537		     header->ext_track_tb.dat_ext_trk_ey.fm_tab_off  != htons(17736)               ||
2538		     header->ext_track_tb.dat_ext_trk_ey.last_hlb_hi != 0                          ||
2539		     header->ext_track_tb.dat_ext_trk_ey.last_pp     != htonl(STp->eod_frame_ppos) ||
2540		     header->dat_fm_tab.fm_part_num                  != OS_DATA_PARTITION          ||
2541		     header->dat_fm_tab.fm_tab_ent_sz                != 4                          ||
2542		     header->dat_fm_tab.fm_tab_ent_cnt               !=
2543			     htons(STp->filemark_cnt<OS_FM_TAB_MAX?STp->filemark_cnt:OS_FM_TAB_MAX)))
2544			printk(KERN_WARNING "%s:W: Failed consistency check ADR 1.4 format\n", name);
2545
2546	}
2547
2548	return 1;
2549}
2550
2551static int osst_analyze_headers(struct osst_tape * STp, struct osst_request ** aSRpnt)
2552{
2553	int	position, ppos;
2554	int	first, last;
2555	int	valid = 0;
2556	char  * name  = tape_name(STp);
2557
2558	position = osst_get_frame_position(STp, aSRpnt);
2559
2560	if (STp->raw) {
2561		STp->header_ok = STp->linux_media = 1;
2562		STp->linux_media_version = 0;
2563		return 1;
2564	}
2565	STp->header_ok = STp->linux_media = STp->linux_media_version = 0;
2566	STp->wrt_pass_cntr = STp->update_frame_cntr = -1;
2567	STp->eod_frame_ppos = STp->first_data_ppos = -1;
2568	STp->first_mark_ppos = STp->last_mark_ppos = STp->last_mark_lbn = -1;
2569#if DEBUG
2570	printk(OSST_DEB_MSG "%s:D: Reading header\n", name);
2571#endif
2572
2573	/* optimization for speed - if we are positioned at ppos 10, read second group first  */
2574	/* TODO try the ADR 1.1 locations for the second group if we have no valid one yet... */
2575
2576	first = position==10?0xbae: 5;
2577	last  = position==10?0xbb3:10;
2578
2579	for (ppos = first; ppos < last; ppos++)
2580		if (__osst_analyze_headers(STp, aSRpnt, ppos))
2581			valid = 1;
2582
2583	first = position==10? 5:0xbae;
2584	last  = position==10?10:0xbb3;
2585
2586	for (ppos = first; ppos < last; ppos++)
2587		if (__osst_analyze_headers(STp, aSRpnt, ppos))
2588			valid = 1;
2589
2590	if (!valid) {
2591		printk(KERN_ERR "%s:E: Failed to find valid ADRL header, new media?\n", name);
2592		STp->eod_frame_ppos = STp->first_data_ppos = 0;
2593		osst_set_frame_position(STp, aSRpnt, 10, 0);
2594		return 0;
2595	}
2596	if (position <= STp->first_data_ppos) {
2597		position = STp->first_data_ppos;
2598		STp->ps[0].drv_file = STp->ps[0].drv_block = STp->frame_seq_number = STp->logical_blk_num = 0;
2599	}
2600	osst_set_frame_position(STp, aSRpnt, position, 0);
2601	STp->header_ok = 1;
2602
2603	return 1;
2604}
2605
2606static int osst_verify_position(struct osst_tape * STp, struct osst_request ** aSRpnt)
2607{
2608	int	frame_position  = STp->first_frame_position;
2609	int	frame_seq_numbr = STp->frame_seq_number;
2610	int	logical_blk_num = STp->logical_blk_num;
2611       	int	halfway_frame   = STp->frame_in_buffer;
2612	int	read_pointer    = STp->buffer->read_pointer;
2613	int	prev_mark_ppos  = -1;
2614	int	actual_mark_ppos, i, n;
2615#if DEBUG
2616	char  * name = tape_name(STp);
2617
2618	printk(OSST_DEB_MSG "%s:D: Verify that the tape is really the one we think before writing\n", name);
2619#endif
2620	osst_set_frame_position(STp, aSRpnt, frame_position - 1, 0);
2621	if (osst_get_logical_frame(STp, aSRpnt, -1, 0) < 0) {
2622#if DEBUG
2623		printk(OSST_DEB_MSG "%s:D: Couldn't get logical blk num in verify_position\n", name);
2624#endif
2625		return (-EIO);
2626	}
2627	if (STp->linux_media_version >= 4) {
2628		for (i=0; i<STp->filemark_cnt; i++)
2629			if ((n=ntohl(STp->header_cache->dat_fm_tab.fm_tab_ent[i])) < frame_position)
2630				prev_mark_ppos = n;
2631	} else
2632		prev_mark_ppos = frame_position - 1;  /* usually - we don't really know */
2633	actual_mark_ppos = STp->buffer->aux->frame_type == OS_FRAME_TYPE_MARKER ?
2634				frame_position - 1 : ntohl(STp->buffer->aux->last_mark_ppos);
2635	if (frame_position  != STp->first_frame_position                   ||
2636	    frame_seq_numbr != STp->frame_seq_number + (halfway_frame?0:1) ||
2637	    prev_mark_ppos  != actual_mark_ppos                            ) {
2638#if DEBUG
2639		printk(OSST_DEB_MSG "%s:D: Block mismatch: fppos %d-%d, fseq %d-%d, mark %d-%d\n", name,
2640				  STp->first_frame_position, frame_position,
2641				  STp->frame_seq_number + (halfway_frame?0:1),
2642				  frame_seq_numbr, actual_mark_ppos, prev_mark_ppos);
2643#endif
2644		return (-EIO);
2645	}
2646	if (halfway_frame) {
2647		/* prepare buffer for append and rewrite on top of original */
2648		osst_set_frame_position(STp, aSRpnt, frame_position - 1, 0);
2649		STp->buffer->buffer_bytes  = read_pointer;
2650		STp->ps[STp->partition].rw = ST_WRITING;
2651		STp->dirty                 = 1;
2652	}
2653	STp->frame_in_buffer  = halfway_frame;
2654	STp->frame_seq_number = frame_seq_numbr;
2655	STp->logical_blk_num  = logical_blk_num;
2656	return 0;
2657}
2658
2659/* Acc. to OnStream, the vers. numbering is the following:
2660 * X.XX for released versions (X=digit),
2661 * XXXY for unreleased versions (Y=letter)
2662 * Ordering 1.05 < 106A < 106B < ...  < 106a < ... < 1.06
2663 * This fn makes monoton numbers out of this scheme ...
2664 */
2665static unsigned int osst_parse_firmware_rev (const char * str)
2666{
2667	if (str[1] == '.') {
2668		return (str[0]-'0')*10000
2669			+(str[2]-'0')*1000
2670			+(str[3]-'0')*100;
2671	} else {
2672		return (str[0]-'0')*10000
2673			+(str[1]-'0')*1000
2674			+(str[2]-'0')*100 - 100
2675			+(str[3]-'@');
2676	}
2677}
2678
2679/*
2680 * Configure the OnStream SCII tape drive for default operation
2681 */
2682static int osst_configure_onstream(struct osst_tape *STp, struct osst_request ** aSRpnt)
2683{
2684	unsigned char                  cmd[MAX_COMMAND_SIZE];
2685	char                         * name = tape_name(STp);
2686	struct osst_request          * SRpnt = * aSRpnt;
2687	osst_mode_parameter_header_t * header;
2688	osst_block_size_page_t       * bs;
2689	osst_capabilities_page_t     * cp;
2690	osst_tape_paramtr_page_t     * prm;
2691	int                            drive_buffer_size;
2692
2693	if (STp->ready != ST_READY) {
2694#if DEBUG
2695	    printk(OSST_DEB_MSG "%s:D: Not Ready\n", name);
2696#endif
2697	    return (-EIO);
2698	}
2699
2700	if (STp->os_fw_rev < 10600) {
2701	    printk(KERN_INFO "%s:I: Old OnStream firmware revision detected (%s),\n", name, STp->device->rev);
2702	    printk(KERN_INFO "%s:I: an upgrade to version 1.06 or above is recommended\n", name);
2703	}
2704
2705	/*
2706	 * Configure 32.5KB (data+aux) frame size.
2707         * Get the current frame size from the block size mode page
2708	 */
2709	memset(cmd, 0, MAX_COMMAND_SIZE);
2710	cmd[0] = MODE_SENSE;
2711	cmd[1] = 8;
2712	cmd[2] = BLOCK_SIZE_PAGE;
2713	cmd[4] = BLOCK_SIZE_PAGE_LENGTH + MODE_HEADER_LENGTH;
2714
2715	SRpnt = osst_do_scsi(SRpnt, STp, cmd, cmd[4], DMA_FROM_DEVICE, STp->timeout, 0, 1);
2716	if (SRpnt == NULL) {
2717#if DEBUG
2718 	    printk(OSST_DEB_MSG "osst :D: Busy\n");
2719#endif
2720	    return (-EBUSY);
2721	}
2722	*aSRpnt = SRpnt;
2723	if ((STp->buffer)->syscall_result != 0) {
2724	    printk (KERN_ERR "%s:E: Can't get tape block size mode page\n", name);
2725	    return (-EIO);
2726	}
2727
2728	header = (osst_mode_parameter_header_t *) (STp->buffer)->b_data;
2729	bs = (osst_block_size_page_t *) ((STp->buffer)->b_data + sizeof(osst_mode_parameter_header_t) + header->bdl);
2730
2731#if DEBUG
2732	printk(OSST_DEB_MSG "%s:D: 32KB play back: %s\n",   name, bs->play32     ? "Yes" : "No");
2733	printk(OSST_DEB_MSG "%s:D: 32.5KB play back: %s\n", name, bs->play32_5   ? "Yes" : "No");
2734	printk(OSST_DEB_MSG "%s:D: 32KB record: %s\n",      name, bs->record32   ? "Yes" : "No");
2735	printk(OSST_DEB_MSG "%s:D: 32.5KB record: %s\n",    name, bs->record32_5 ? "Yes" : "No");
2736#endif
2737
2738	/*
2739	 * Configure default auto columns mode, 32.5KB transfer mode
2740	 */
2741	bs->one = 1;
2742	bs->play32 = 0;
2743	bs->play32_5 = 1;
2744	bs->record32 = 0;
2745	bs->record32_5 = 1;
2746
2747	memset(cmd, 0, MAX_COMMAND_SIZE);
2748	cmd[0] = MODE_SELECT;
2749	cmd[1] = 0x10;
2750	cmd[4] = BLOCK_SIZE_PAGE_LENGTH + MODE_HEADER_LENGTH;
2751
2752	SRpnt = osst_do_scsi(SRpnt, STp, cmd, cmd[4], DMA_TO_DEVICE, STp->timeout, 0, 1);
2753	*aSRpnt = SRpnt;
2754	if ((STp->buffer)->syscall_result != 0) {
2755	    printk (KERN_ERR "%s:E: Couldn't set tape block size mode page\n", name);
2756	    return (-EIO);
2757	}
2758
2759#if DEBUG
2760	printk(KERN_INFO "%s:D: Drive Block Size changed to 32.5K\n", name);
2761	 /*
2762	 * In debug mode, we want to see as many errors as possible
2763	 * to test the error recovery mechanism.
2764	 */
2765	osst_set_retries(STp, aSRpnt, 0);
2766	SRpnt = * aSRpnt;
2767#endif
2768
2769	/*
2770	 * Set vendor name to 'LIN4' for "Linux support version 4".
2771	 */
2772
2773	memset(cmd, 0, MAX_COMMAND_SIZE);
2774	cmd[0] = MODE_SELECT;
2775	cmd[1] = 0x10;
2776	cmd[4] = VENDOR_IDENT_PAGE_LENGTH + MODE_HEADER_LENGTH;
2777
2778	header->mode_data_length = VENDOR_IDENT_PAGE_LENGTH + MODE_HEADER_LENGTH - 1;
2779	header->medium_type      = 0;	/* Medium Type - ignoring */
2780	header->dsp              = 0;	/* Reserved */
2781	header->bdl              = 0;	/* Block Descriptor Length */
2782
2783	(STp->buffer)->b_data[MODE_HEADER_LENGTH + 0] = VENDOR_IDENT_PAGE | (1 << 7);
2784	(STp->buffer)->b_data[MODE_HEADER_LENGTH + 1] = 6;
2785	(STp->buffer)->b_data[MODE_HEADER_LENGTH + 2] = 'L';
2786	(STp->buffer)->b_data[MODE_HEADER_LENGTH + 3] = 'I';
2787	(STp->buffer)->b_data[MODE_HEADER_LENGTH + 4] = 'N';
2788	(STp->buffer)->b_data[MODE_HEADER_LENGTH + 5] = '4';
2789	(STp->buffer)->b_data[MODE_HEADER_LENGTH + 6] = 0;
2790	(STp->buffer)->b_data[MODE_HEADER_LENGTH + 7] = 0;
2791
2792	SRpnt = osst_do_scsi(SRpnt, STp, cmd, cmd[4], DMA_TO_DEVICE, STp->timeout, 0, 1);
2793	*aSRpnt = SRpnt;
2794
2795	if ((STp->buffer)->syscall_result != 0) {
2796	    printk (KERN_ERR "%s:E: Couldn't set vendor name to %s\n", name,
2797			(char *) ((STp->buffer)->b_data + MODE_HEADER_LENGTH + 2));
2798	    return (-EIO);
2799	}
2800
2801	memset(cmd, 0, MAX_COMMAND_SIZE);
2802	cmd[0] = MODE_SENSE;
2803	cmd[1] = 8;
2804	cmd[2] = CAPABILITIES_PAGE;
2805	cmd[4] = CAPABILITIES_PAGE_LENGTH + MODE_HEADER_LENGTH;
2806
2807	SRpnt = osst_do_scsi(SRpnt, STp, cmd, cmd[4], DMA_FROM_DEVICE, STp->timeout, 0, 1);
2808	*aSRpnt = SRpnt;
2809
2810	if ((STp->buffer)->syscall_result != 0) {
2811	    printk (KERN_ERR "%s:E: Can't get capabilities page\n", name);
2812	    return (-EIO);
2813	}
2814
2815	header = (osst_mode_parameter_header_t *) (STp->buffer)->b_data;
2816	cp     = (osst_capabilities_page_t    *) ((STp->buffer)->b_data +
2817		 sizeof(osst_mode_parameter_header_t) + header->bdl);
2818
2819	drive_buffer_size = ntohs(cp->buffer_size) / 2;
2820
2821	memset(cmd, 0, MAX_COMMAND_SIZE);
2822	cmd[0] = MODE_SENSE;
2823	cmd[1] = 8;
2824	cmd[2] = TAPE_PARAMTR_PAGE;
2825	cmd[4] = TAPE_PARAMTR_PAGE_LENGTH + MODE_HEADER_LENGTH;
2826
2827	SRpnt = osst_do_scsi(SRpnt, STp, cmd, cmd[4], DMA_FROM_DEVICE, STp->timeout, 0, 1);
2828	*aSRpnt = SRpnt;
2829
2830	if ((STp->buffer)->syscall_result != 0) {
2831	    printk (KERN_ERR "%s:E: Can't get tape parameter page\n", name);
2832	    return (-EIO);
2833	}
2834
2835	header = (osst_mode_parameter_header_t *) (STp->buffer)->b_data;
2836	prm    = (osst_tape_paramtr_page_t    *) ((STp->buffer)->b_data +
2837		 sizeof(osst_mode_parameter_header_t) + header->bdl);
2838
2839	STp->density  = prm->density;
2840	STp->capacity = ntohs(prm->segtrk) * ntohs(prm->trks);
2841#if DEBUG
2842	printk(OSST_DEB_MSG "%s:D: Density %d, tape length: %dMB, drive buffer size: %dKB\n",
2843			  name, STp->density, STp->capacity / 32, drive_buffer_size);
2844#endif
2845
2846	return 0;
2847
2848}
2849
2850
2851/* Step over EOF if it has been inadvertently crossed (ioctl not used because
2852   it messes up the block number). */
2853static int cross_eof(struct osst_tape *STp, struct osst_request ** aSRpnt, int forward)
2854{
2855	int	result;
2856	char  * name = tape_name(STp);
2857
2858#if DEBUG
2859	if (debugging)
2860		printk(OSST_DEB_MSG "%s:D: Stepping over filemark %s.\n",
2861	   			  name, forward ? "forward" : "backward");
2862#endif
2863
2864	if (forward) {
2865	   /* assumes that the filemark is already read by the drive, so this is low cost */
2866	   result = osst_space_over_filemarks_forward_slow(STp, aSRpnt, MTFSF, 1);
2867	}
2868	else
2869	   /* assumes this is only called if we just read the filemark! */
2870	   result = osst_seek_logical_blk(STp, aSRpnt, STp->logical_blk_num - 1);
2871
2872	if (result < 0)
2873	   printk(KERN_WARNING "%s:W: Stepping over filemark %s failed.\n",
2874				name, forward ? "forward" : "backward");
2875
2876	return result;
2877}
2878
2879
2880/* Get the tape position. */
2881
2882static int osst_get_frame_position(struct osst_tape *STp, struct osst_request ** aSRpnt)
2883{
2884	unsigned char		scmd[MAX_COMMAND_SIZE];
2885	struct osst_request   * SRpnt;
2886	int			result = 0;
2887	char    	      * name   = tape_name(STp);
2888
2889	/* KG: We want to be able to use it for checking Write Buffer availability
2890	 *  and thus don't want to risk to overwrite anything. Exchange buffers ... */
2891	char		mybuf[24];
2892	char	      * olddata = STp->buffer->b_data;
2893	int		oldsize = STp->buffer->buffer_size;
2894
2895	if (STp->ready != ST_READY) return (-EIO);
2896
2897	memset (scmd, 0, MAX_COMMAND_SIZE);
2898	scmd[0] = READ_POSITION;
2899
2900	STp->buffer->b_data = mybuf; STp->buffer->buffer_size = 24;
2901	SRpnt = osst_do_scsi(*aSRpnt, STp, scmd, 20, DMA_FROM_DEVICE,
2902				      STp->timeout, MAX_RETRIES, 1);
2903	if (!SRpnt) {
2904		STp->buffer->b_data = olddata; STp->buffer->buffer_size = oldsize;
2905		return (-EBUSY);
2906	}
2907	*aSRpnt = SRpnt;
2908
2909	if (STp->buffer->syscall_result)
2910		result = ((SRpnt->sense[2] & 0x0f) == 3) ? -EIO : -EINVAL;	/* 3: Write Error */
2911
2912	if (result == -EINVAL)
2913		printk(KERN_ERR "%s:E: Can't read tape position.\n", name);
2914	else {
2915		if (result == -EIO) {	/* re-read position - this needs to preserve media errors */
2916			unsigned char mysense[16];
2917			memcpy (mysense, SRpnt->sense, 16);
2918			memset (scmd, 0, MAX_COMMAND_SIZE);
2919			scmd[0] = READ_POSITION;
2920			STp->buffer->b_data = mybuf; STp->buffer->buffer_size = 24;
2921			SRpnt = osst_do_scsi(SRpnt, STp, scmd, 20, DMA_FROM_DEVICE,
2922						    STp->timeout, MAX_RETRIES, 1);
2923#if DEBUG
2924			printk(OSST_DEB_MSG "%s:D: Reread position, reason=[%02x:%02x:%02x], result=[%s%02x:%02x:%02x]\n",
2925					name, mysense[2], mysense[12], mysense[13], STp->buffer->syscall_result?"":"ok:",
2926					SRpnt->sense[2],SRpnt->sense[12],SRpnt->sense[13]);
2927#endif
2928			if (!STp->buffer->syscall_result)
2929				memcpy (SRpnt->sense, mysense, 16);
2930			else
2931				printk(KERN_WARNING "%s:W: Double error in get position\n", name);
2932		}
2933		STp->first_frame_position = ((STp->buffer)->b_data[4] << 24)
2934					  + ((STp->buffer)->b_data[5] << 16)
2935					  + ((STp->buffer)->b_data[6] << 8)
2936					  +  (STp->buffer)->b_data[7];
2937		STp->last_frame_position  = ((STp->buffer)->b_data[ 8] << 24)
2938					  + ((STp->buffer)->b_data[ 9] << 16)
2939					  + ((STp->buffer)->b_data[10] <<  8)
2940					  +  (STp->buffer)->b_data[11];
2941		STp->cur_frames           =  (STp->buffer)->b_data[15];
2942#if DEBUG
2943		if (debugging) {
2944			printk(OSST_DEB_MSG "%s:D: Drive Positions: host %d, tape %d%s, buffer %d\n", name,
2945					    STp->first_frame_position, STp->last_frame_position,
2946					    ((STp->buffer)->b_data[0]&0x80)?" (BOP)":
2947					    ((STp->buffer)->b_data[0]&0x40)?" (EOP)":"",
2948					    STp->cur_frames);
2949		}
2950#endif
2951		if (STp->cur_frames == 0 && STp->first_frame_position != STp->last_frame_position) {
2952#if DEBUG
2953			printk(OSST_DEB_MSG "%s:D: Correcting read position %d, %d, %d\n", name,
2954					STp->first_frame_position, STp->last_frame_position, STp->cur_frames);
2955#endif
2956			STp->first_frame_position = STp->last_frame_position;
2957		}
2958	}
2959	STp->buffer->b_data = olddata; STp->buffer->buffer_size = oldsize;
2960
2961	return (result == 0 ? STp->first_frame_position : result);
2962}
2963
2964
2965/* Set the tape block */
2966static int osst_set_frame_position(struct osst_tape *STp, struct osst_request ** aSRpnt, int ppos, int skip)
2967{
2968	unsigned char		scmd[MAX_COMMAND_SIZE];
2969	struct osst_request   * SRpnt;
2970	struct st_partstat    * STps;
2971	int			result = 0;
2972	int			pp     = (ppos == 3000 && !skip)? 0 : ppos;
2973	char		      * name   = tape_name(STp);
2974
2975	if (STp->ready != ST_READY) return (-EIO);
2976
2977	STps = &(STp->ps[STp->partition]);
2978
2979	if (ppos < 0 || ppos > STp->capacity) {
2980		printk(KERN_WARNING "%s:W: Reposition request %d out of range\n", name, ppos);
2981		pp = ppos = ppos < 0 ? 0 : (STp->capacity - 1);
2982		result = (-EINVAL);
2983	}
2984
2985	do {
2986#if DEBUG
2987		if (debugging)
2988			printk(OSST_DEB_MSG "%s:D: Setting ppos to %d.\n", name, pp);
2989#endif
2990		memset (scmd, 0, MAX_COMMAND_SIZE);
2991		scmd[0] = SEEK_10;
2992		scmd[1] = 1;
2993		scmd[3] = (pp >> 24);
2994		scmd[4] = (pp >> 16);
2995		scmd[5] = (pp >> 8);
2996		scmd[6] =  pp;
2997		if (skip)
2998			scmd[9] = 0x80;
2999
3000		SRpnt = osst_do_scsi(*aSRpnt, STp, scmd, 0, DMA_NONE, STp->long_timeout,
3001								MAX_RETRIES, 1);
3002		if (!SRpnt)
3003			return (-EBUSY);
3004		*aSRpnt  = SRpnt;
3005
3006		if ((STp->buffer)->syscall_result != 0) {
3007#if DEBUG
3008			printk(OSST_DEB_MSG "%s:D: SEEK command from %d to %d failed.\n",
3009					name, STp->first_frame_position, pp);
3010#endif
3011			result = (-EIO);
3012		}
3013		if (pp != ppos)
3014			osst_wait_ready(STp, aSRpnt, 5 * 60, OSST_WAIT_POSITION_COMPLETE);
3015	} while ((pp != ppos) && (pp = ppos));
3016	STp->first_frame_position = STp->last_frame_position = ppos;
3017	STps->eof = ST_NOEOF;
3018	STps->at_sm = 0;
3019	STps->rw = ST_IDLE;
3020	STp->frame_in_buffer = 0;
3021	return result;
3022}
3023
3024static int osst_write_trailer(struct osst_tape *STp, struct osst_request ** aSRpnt, int leave_at_EOT)
3025{
3026	struct st_partstat * STps = &(STp->ps[STp->partition]);
3027	int result = 0;
3028
3029	if (STp->write_type != OS_WRITE_NEW_MARK) {
3030		/* true unless the user wrote the filemark for us */
3031		result = osst_flush_drive_buffer(STp, aSRpnt);
3032		if (result < 0) goto out;
3033		result = osst_write_filemark(STp, aSRpnt);
3034		if (result < 0) goto out;
3035
3036		if (STps->drv_file >= 0)
3037			STps->drv_file++ ;
3038		STps->drv_block = 0;
3039	}
3040	result = osst_write_eod(STp, aSRpnt);
3041	osst_write_header(STp, aSRpnt, leave_at_EOT);
3042
3043	STps->eof = ST_FM;
3044out:
3045	return result;
3046}
3047
3048/* osst versions of st functions - augmented and stripped to suit OnStream only */
3049
3050/* Flush the write buffer (never need to write if variable blocksize). */
3051static int osst_flush_write_buffer(struct osst_tape *STp, struct osst_request ** aSRpnt)
3052{
3053	int			offset, transfer, blks = 0;
3054	int			result = 0;
3055	unsigned char		cmd[MAX_COMMAND_SIZE];
3056	struct osst_request   * SRpnt = *aSRpnt;
3057	struct st_partstat    * STps;
3058	char		      * name = tape_name(STp);
3059
3060	if ((STp->buffer)->writing) {
3061		if (SRpnt == (STp->buffer)->last_SRpnt)
3062#if DEBUG
3063			{ printk(OSST_DEB_MSG
3064	 "%s:D: aSRpnt points to osst_request that write_behind_check will release -- cleared\n", name);
3065#endif
3066			*aSRpnt = SRpnt = NULL;
3067#if DEBUG
3068			} else if (SRpnt)
3069				printk(OSST_DEB_MSG
3070	 "%s:D: aSRpnt does not point to osst_request that write_behind_check will release -- strange\n", name);
3071#endif
3072		osst_write_behind_check(STp);
3073		if ((STp->buffer)->syscall_result) {
3074#if DEBUG
3075			if (debugging)
3076				printk(OSST_DEB_MSG "%s:D: Async write error (flush) %x.\n",
3077				       name, (STp->buffer)->midlevel_result);
3078#endif
3079			if ((STp->buffer)->midlevel_result == INT_MAX)
3080				return (-ENOSPC);
3081			return (-EIO);
3082		}
3083	}
3084
3085	result = 0;
3086	if (STp->dirty == 1) {
3087
3088		STp->write_count++;
3089		STps     = &(STp->ps[STp->partition]);
3090		STps->rw = ST_WRITING;
3091		offset   = STp->buffer->buffer_bytes;
3092		blks     = (offset + STp->block_size - 1) / STp->block_size;
3093		transfer = OS_FRAME_SIZE;
3094
3095		if (offset < OS_DATA_SIZE)
3096			osst_zero_buffer_tail(STp->buffer);
3097
3098		if (STp->poll)
3099			if (osst_wait_frame (STp, aSRpnt, STp->first_frame_position, -50, 120))
3100				result = osst_recover_wait_frame(STp, aSRpnt, 1);
3101
3102		memset(cmd, 0, MAX_COMMAND_SIZE);
3103		cmd[0] = WRITE_6;
3104		cmd[1] = 1;
3105		cmd[4] = 1;
3106
3107		switch	(STp->write_type) {
3108		   case OS_WRITE_DATA:
3109#if DEBUG
3110   			if (debugging)
3111				printk(OSST_DEB_MSG "%s:D: Writing %d blocks to frame %d, lblks %d-%d\n",
3112					name, blks, STp->frame_seq_number,
3113					STp->logical_blk_num - blks, STp->logical_blk_num - 1);
3114#endif
3115			osst_init_aux(STp, OS_FRAME_TYPE_DATA, STp->frame_seq_number++,
3116				      STp->logical_blk_num - blks, STp->block_size, blks);
3117			break;
3118		   case OS_WRITE_EOD:
3119			osst_init_aux(STp, OS_FRAME_TYPE_EOD, STp->frame_seq_number++,
3120				      STp->logical_blk_num, 0, 0);
3121			break;
3122		   case OS_WRITE_NEW_MARK:
3123			osst_init_aux(STp, OS_FRAME_TYPE_MARKER, STp->frame_seq_number++,
3124				      STp->logical_blk_num++, 0, blks=1);
3125			break;
3126		   case OS_WRITE_HEADER:
3127			osst_init_aux(STp, OS_FRAME_TYPE_HEADER, 0, 0, 0, blks=0);
3128			break;
3129		default: /* probably FILLER */
3130			osst_init_aux(STp, OS_FRAME_TYPE_FILL, 0, 0, 0, 0);
3131		}
3132#if DEBUG
3133		if (debugging)
3134			printk(OSST_DEB_MSG "%s:D: Flushing %d bytes, Transferring %d bytes in %d lblocks.\n",
3135			  			 name, offset, transfer, blks);
3136#endif
3137
3138		SRpnt = osst_do_scsi(*aSRpnt, STp, cmd, transfer, DMA_TO_DEVICE,
3139					      STp->timeout, MAX_RETRIES, 1);
3140		*aSRpnt = SRpnt;
3141		if (!SRpnt)
3142			return (-EBUSY);
3143
3144		if ((STp->buffer)->syscall_result != 0) {
3145#if DEBUG
3146			printk(OSST_DEB_MSG
3147				"%s:D: write sense [0]=0x%02x [2]=%02x [12]=%02x [13]=%02x\n",
3148				name, SRpnt->sense[0], SRpnt->sense[2],
3149				SRpnt->sense[12], SRpnt->sense[13]);
3150#endif
3151			if ((SRpnt->sense[0] & 0x70) == 0x70 &&
3152			    (SRpnt->sense[2] & 0x40) && /* FIXME - SC-30 drive doesn't assert EOM bit */
3153			    (SRpnt->sense[2] & 0x0f) == NO_SENSE) {
3154				STp->dirty = 0;
3155				(STp->buffer)->buffer_bytes = 0;
3156				result = (-ENOSPC);
3157			}
3158			else {
3159				if (osst_write_error_recovery(STp, aSRpnt, 1)) {
3160					printk(KERN_ERR "%s:E: Error on flush write.\n", name);
3161					result = (-EIO);
3162				}
3163			}
3164			STps->drv_block = (-1);		/* FIXME - even if write recovery succeeds? */
3165		}
3166		else {
3167			STp->first_frame_position++;
3168			STp->dirty = 0;
3169			(STp->buffer)->buffer_bytes = 0;
3170		}
3171	}
3172#if DEBUG
3173	printk(OSST_DEB_MSG "%s:D: Exit flush write buffer with code %d\n", name, result);
3174#endif
3175	return result;
3176}
3177
3178
3179/* Flush the tape buffer. The tape will be positioned correctly unless
3180   seek_next is true. */
3181static int osst_flush_buffer(struct osst_tape * STp, struct osst_request ** aSRpnt, int seek_next)
3182{
3183	struct st_partstat * STps;
3184	int    backspace = 0, result = 0;
3185#if DEBUG
3186	char * name = tape_name(STp);
3187#endif
3188
3189	/*
3190	 * If there was a bus reset, block further access
3191	 * to this device.
3192	 */
3193	if( STp->pos_unknown)
3194		return (-EIO);
3195
3196	if (STp->ready != ST_READY)
3197		return 0;
3198
3199	STps = &(STp->ps[STp->partition]);
3200	if (STps->rw == ST_WRITING || STp->dirty) {	/* Writing */
3201		STp->write_type = OS_WRITE_DATA;
3202		return osst_flush_write_buffer(STp, aSRpnt);
3203	}
3204	if (STp->block_size == 0)
3205		return 0;
3206
3207#if DEBUG
3208	printk(OSST_DEB_MSG "%s:D: Reached flush (read) buffer\n", name);
3209#endif
3210
3211	if (!STp->can_bsr) {
3212		backspace = ((STp->buffer)->buffer_bytes + (STp->buffer)->read_pointer) / STp->block_size -
3213			    ((STp->buffer)->read_pointer + STp->block_size - 1        ) / STp->block_size ;
3214		(STp->buffer)->buffer_bytes = 0;
3215		(STp->buffer)->read_pointer = 0;
3216		STp->frame_in_buffer = 0;		/* FIXME is this relevant w. OSST? */
3217	}
3218
3219	if (!seek_next) {
3220		if (STps->eof == ST_FM_HIT) {
3221			result = cross_eof(STp, aSRpnt, 0); /* Back over the EOF hit */
3222			if (!result)
3223				STps->eof = ST_NOEOF;
3224			else {
3225				if (STps->drv_file >= 0)
3226					STps->drv_file++;
3227				STps->drv_block = 0;
3228			}
3229		}
3230		if (!result && backspace > 0)	/* TODO -- design and run a test case for this */
3231			result = osst_seek_logical_blk(STp, aSRpnt, STp->logical_blk_num - backspace);
3232	}
3233	else if (STps->eof == ST_FM_HIT) {
3234		if (STps->drv_file >= 0)
3235			STps->drv_file++;
3236		STps->drv_block = 0;
3237		STps->eof = ST_NOEOF;
3238	}
3239
3240	return result;
3241}
3242
3243static int osst_write_frame(struct osst_tape * STp, struct osst_request ** aSRpnt, int synchronous)
3244{
3245	unsigned char		cmd[MAX_COMMAND_SIZE];
3246	struct osst_request   * SRpnt;
3247	int			blks;
3248#if DEBUG
3249	char		      * name = tape_name(STp);
3250#endif
3251
3252	if ((!STp-> raw) && (STp->first_frame_position == 0xbae)) { /* _must_ preserve buffer! */
3253#if DEBUG
3254		printk(OSST_DEB_MSG "%s:D: Reaching config partition.\n", name);
3255#endif
3256		if (osst_flush_drive_buffer(STp, aSRpnt) < 0) {
3257			return (-EIO);
3258		}
3259		/* error recovery may have bumped us past the header partition */
3260		if (osst_get_frame_position(STp, aSRpnt) < 0xbb8) {
3261#if DEBUG
3262			printk(OSST_DEB_MSG "%s:D: Skipping over config partition.\n", name);
3263#endif
3264		osst_position_tape_and_confirm(STp, aSRpnt, 0xbb8);
3265		}
3266	}
3267
3268	if (STp->poll)
3269		if (osst_wait_frame (STp, aSRpnt, STp->first_frame_position, -48, 120))
3270			if (osst_recover_wait_frame(STp, aSRpnt, 1))
3271				return (-EIO);
3272
3273//	osst_build_stats(STp, &SRpnt);
3274
3275	STp->ps[STp->partition].rw = ST_WRITING;
3276	STp->write_type            = OS_WRITE_DATA;
3277
3278	memset(cmd, 0, MAX_COMMAND_SIZE);
3279	cmd[0]   = WRITE_6;
3280	cmd[1]   = 1;
3281	cmd[4]   = 1;						/* one frame at a time... */
3282	blks     = STp->buffer->buffer_bytes / STp->block_size;
3283#if DEBUG
3284	if (debugging)
3285		printk(OSST_DEB_MSG "%s:D: Writing %d blocks to frame %d, lblks %d-%d\n", name, blks,
3286			STp->frame_seq_number, STp->logical_blk_num - blks, STp->logical_blk_num - 1);
3287#endif
3288	osst_init_aux(STp, OS_FRAME_TYPE_DATA, STp->frame_seq_number++,
3289		      STp->logical_blk_num - blks, STp->block_size, blks);
3290
3291#if DEBUG
3292	if (!synchronous)
3293		STp->write_pending = 1;
3294#endif
3295	SRpnt = osst_do_scsi(*aSRpnt, STp, cmd, OS_FRAME_SIZE, DMA_TO_DEVICE, STp->timeout,
3296									MAX_RETRIES, synchronous);
3297	if (!SRpnt)
3298		return (-EBUSY);
3299	*aSRpnt = SRpnt;
3300
3301	if (synchronous) {
3302		if (STp->buffer->syscall_result != 0) {
3303#if DEBUG
3304			if (debugging)
3305				printk(OSST_DEB_MSG "%s:D: Error on write:\n", name);
3306#endif
3307			if ((SRpnt->sense[0] & 0x70) == 0x70 &&
3308			    (SRpnt->sense[2] & 0x40)) {
3309				if ((SRpnt->sense[2] & 0x0f) == VOLUME_OVERFLOW)
3310					return (-ENOSPC);
3311			}
3312			else {
3313				if (osst_write_error_recovery(STp, aSRpnt, 1))
3314					return (-EIO);
3315			}
3316		}
3317		else
3318			STp->first_frame_position++;
3319	}
3320
3321	STp->write_count++;
3322
3323	return 0;
3324}
3325
3326/* Lock or unlock the drive door. Don't use when struct osst_request allocated. */
3327static int do_door_lock(struct osst_tape * STp, int do_lock)
3328{
3329	int retval, cmd;
3330
3331	cmd = do_lock ? SCSI_IOCTL_DOORLOCK : SCSI_IOCTL_DOORUNLOCK;
3332#if DEBUG
3333	printk(OSST_DEB_MSG "%s:D: %socking drive door.\n", tape_name(STp), do_lock ? "L" : "Unl");
3334#endif
3335	retval = scsi_ioctl(STp->device, cmd, NULL);
3336	if (!retval) {
3337		STp->door_locked = do_lock ? ST_LOCKED_EXPLICIT : ST_UNLOCKED;
3338	}
3339	else {
3340		STp->door_locked = ST_LOCK_FAILS;
3341	}
3342	return retval;
3343}
3344
3345/* Set the internal state after reset */
3346static void reset_state(struct osst_tape *STp)
3347{
3348	int i;
3349	struct st_partstat *STps;
3350
3351	STp->pos_unknown = 0;
3352	for (i = 0; i < ST_NBR_PARTITIONS; i++) {
3353		STps = &(STp->ps[i]);
3354		STps->rw = ST_IDLE;
3355		STps->eof = ST_NOEOF;
3356		STps->at_sm = 0;
3357		STps->last_block_valid = 0;
3358		STps->drv_block = -1;
3359		STps->drv_file = -1;
3360	}
3361}
3362
3363
3364/* Entry points to osst */
3365
3366/* Write command */
3367static ssize_t osst_write(struct file * filp, const char __user * buf, size_t count, loff_t *ppos)
3368{
3369	ssize_t		      total, retval = 0;
3370	ssize_t		      i, do_count, blks, transfer;
3371	int		      write_threshold;
3372	int		      doing_write = 0;
3373	const char   __user * b_point;
3374	struct osst_request * SRpnt = NULL;
3375	struct st_modedef   * STm;
3376	struct st_partstat  * STps;
3377	struct osst_tape    * STp  = filp->private_data;
3378	char		    * name = tape_name(STp);
3379
3380
3381	if (mutex_lock_interruptible(&STp->lock))
3382		return (-ERESTARTSYS);
3383
3384	/*
3385	 * If we are in the middle of error recovery, don't let anyone
3386	 * else try and use this device.  Also, if error recovery fails, it
3387	 * may try and take the device offline, in which case all further
3388	 * access to the device is prohibited.
3389	 */
3390	if( !scsi_block_when_processing_errors(STp->device) ) {
3391		retval = (-ENXIO);
3392		goto out;
3393	}
3394
3395	if (STp->ready != ST_READY) {
3396		if (STp->ready == ST_NO_TAPE)
3397			retval = (-ENOMEDIUM);
3398		else
3399			retval = (-EIO);
3400		goto out;
3401	}
3402	STm = &(STp->modes[STp->current_mode]);
3403	if (!STm->defined) {
3404		retval = (-ENXIO);
3405		goto out;
3406	}
3407	if (count == 0)
3408		goto out;
3409
3410	/*
3411	 * If there was a bus reset, block further access
3412	 * to this device.
3413	 */
3414	if (STp->pos_unknown) {
3415		retval = (-EIO);
3416		goto out;
3417	}
3418
3419#if DEBUG
3420	if (!STp->in_use) {
3421		printk(OSST_DEB_MSG "%s:D: Incorrect device.\n", name);
3422		retval = (-EIO);
3423		goto out;
3424	}
3425#endif
3426
3427	if (STp->write_prot) {
3428		retval = (-EACCES);
3429		goto out;
3430	}
3431
3432	/* Write must be integral number of blocks */
3433	if (STp->block_size != 0 && (count % STp->block_size) != 0) {
3434		printk(KERN_ERR "%s:E: Write (%Zd bytes) not multiple of tape block size (%d%c).\n",
3435				       name, count, STp->block_size<1024?
3436				       STp->block_size:STp->block_size/1024, STp->block_size<1024?'b':'k');
3437		retval = (-EINVAL);
3438		goto out;
3439	}
3440
3441	if (STp->first_frame_position >= STp->capacity - OSST_EOM_RESERVE) {
3442		printk(KERN_ERR "%s:E: Write truncated at EOM early warning (frame %d).\n",
3443				       name, STp->first_frame_position);
3444		retval = (-ENOSPC);
3445		goto out;
3446	}
3447
3448	if (STp->do_auto_lock && STp->door_locked == ST_UNLOCKED && !do_door_lock(STp, 1))
3449		STp->door_locked = ST_LOCKED_AUTO;
3450
3451	STps = &(STp->ps[STp->partition]);
3452
3453	if (STps->rw == ST_READING) {
3454#if DEBUG
3455		printk(OSST_DEB_MSG "%s:D: Switching from read to write at file %d, block %d\n", name,
3456					STps->drv_file, STps->drv_block);
3457#endif
3458		retval = osst_flush_buffer(STp, &SRpnt, 0);
3459		if (retval)
3460			goto out;
3461		STps->rw = ST_IDLE;
3462	}
3463	if (STps->rw != ST_WRITING) {
3464		/* Are we totally rewriting this tape? */
3465		if (!STp->header_ok ||
3466		    (STp->first_frame_position == STp->first_data_ppos && STps->drv_block < 0) ||
3467		    (STps->drv_file == 0 && STps->drv_block == 0)) {
3468			STp->wrt_pass_cntr++;
3469#if DEBUG
3470			printk(OSST_DEB_MSG "%s:D: Allocating next write pass counter: %d\n",
3471						  name, STp->wrt_pass_cntr);
3472#endif
3473			osst_reset_header(STp, &SRpnt);
3474			STps->drv_file = STps->drv_block = 0;
3475		}
3476		/* Do we know where we'll be writing on the tape? */
3477		else {
3478			if ((STp->fast_open && osst_verify_position(STp, &SRpnt)) ||
3479			  		STps->drv_file < 0 || STps->drv_block < 0) {
3480				if (STp->first_frame_position == STp->eod_frame_ppos) {	/* at EOD */
3481			  		STps->drv_file = STp->filemark_cnt;
3482			  		STps->drv_block = 0;
3483				}
3484				else {
3485					/* We have no idea where the tape is positioned - give up */
3486#if DEBUG
3487					printk(OSST_DEB_MSG
3488						"%s:D: Cannot write at indeterminate position.\n", name);
3489#endif
3490					retval = (-EIO);
3491					goto out;
3492				}
3493      			}
3494			if ((STps->drv_file + STps->drv_block) > 0 && STps->drv_file < STp->filemark_cnt) {
3495				STp->filemark_cnt = STps->drv_file;
3496				STp->last_mark_ppos =
3497				       	ntohl(STp->header_cache->dat_fm_tab.fm_tab_ent[STp->filemark_cnt-1]);
3498				printk(KERN_WARNING
3499					"%s:W: Overwriting file %d with old write pass counter %d\n",
3500						name, STps->drv_file, STp->wrt_pass_cntr);
3501				printk(KERN_WARNING
3502					"%s:W: may lead to stale data being accepted on reading back!\n",
3503						name);
3504#if DEBUG
3505				printk(OSST_DEB_MSG
3506				  "%s:D: resetting filemark count to %d and last mark ppos,lbn to %d,%d\n",
3507					name, STp->filemark_cnt, STp->last_mark_ppos, STp->last_mark_lbn);
3508#endif
3509			}
3510		}
3511		STp->fast_open = 0;
3512	}
3513	if (!STp->header_ok) {
3514#if DEBUG
3515		printk(OSST_DEB_MSG "%s:D: Write cannot proceed without valid headers\n", name);
3516#endif
3517		retval = (-EIO);
3518		goto out;
3519	}
3520
3521	if ((STp->buffer)->writing) {
3522if (SRpnt) printk(KERN_ERR "%s:A: Not supposed to have SRpnt at line %d\n", name, __LINE__);
3523		osst_write_behind_check(STp);
3524		if ((STp->buffer)->syscall_result) {
3525#if DEBUG
3526		if (debugging)
3527			printk(OSST_DEB_MSG "%s:D: Async write error (write) %x.\n", name,
3528						 (STp->buffer)->midlevel_result);
3529#endif
3530		if ((STp->buffer)->midlevel_result == INT_MAX)
3531			STps->eof = ST_EOM_OK;
3532		else
3533			STps->eof = ST_EOM_ERROR;
3534		}
3535	}
3536	if (STps->eof == ST_EOM_OK) {
3537		retval = (-ENOSPC);
3538		goto out;
3539	}
3540	else if (STps->eof == ST_EOM_ERROR) {
3541		retval = (-EIO);
3542		goto out;
3543	}
3544
3545	/* Check the buffer readability in cases where copy_user might catch
3546		 the problems after some tape movement. */
3547	if ((copy_from_user(&i, buf, 1) != 0 ||
3548	     copy_from_user(&i, buf + count - 1, 1) != 0)) {
3549		retval = (-EFAULT);
3550		goto out;
3551	}
3552
3553	if (!STm->do_buffer_writes) {
3554		write_threshold = 1;
3555	}
3556	else
3557		write_threshold = (STp->buffer)->buffer_blocks * STp->block_size;
3558	if (!STm->do_async_writes)
3559		write_threshold--;
3560
3561	total = count;
3562#if DEBUG
3563	if (debugging)
3564		printk(OSST_DEB_MSG "%s:D: Writing %d bytes to file %d block %d lblk %d fseq %d fppos %d\n",
3565				name, (int) count, STps->drv_file, STps->drv_block,
3566				STp->logical_blk_num, STp->frame_seq_number, STp->first_frame_position);
3567#endif
3568	b_point = buf;
3569	while ((STp->buffer)->buffer_bytes + count > write_threshold)
3570	{
3571		doing_write = 1;
3572		do_count = (STp->buffer)->buffer_blocks * STp->block_size -
3573			   (STp->buffer)->buffer_bytes;
3574		if (do_count > count)
3575			do_count = count;
3576
3577		i = append_to_buffer(b_point, STp->buffer, do_count);
3578		if (i) {
3579			retval = i;
3580			goto out;
3581		}
3582
3583		blks = do_count / STp->block_size;
3584		STp->logical_blk_num += blks;  /* logical_blk_num is incremented as data is moved from user */
3585
3586		i = osst_write_frame(STp, &SRpnt, 1);
3587
3588		if (i == (-ENOSPC)) {
3589			transfer = STp->buffer->writing;	/* FIXME -- check this logic */
3590			if (transfer <= do_count) {
3591				*ppos += do_count - transfer;
3592				count -= do_count - transfer;
3593				if (STps->drv_block >= 0) {
3594					STps->drv_block += (do_count - transfer) / STp->block_size;
3595				}
3596				STps->eof = ST_EOM_OK;
3597				retval = (-ENOSPC);		/* EOM within current request */
3598#if DEBUG
3599				if (debugging)
3600				      printk(OSST_DEB_MSG "%s:D: EOM with %d bytes unwritten.\n",
3601							     name, (int) transfer);
3602#endif
3603			}
3604			else {
3605				STps->eof = ST_EOM_ERROR;
3606				STps->drv_block = (-1);		/* Too cautious? */
3607				retval = (-EIO);		/* EOM for old data */
3608#if DEBUG
3609				if (debugging)
3610				      printk(OSST_DEB_MSG "%s:D: EOM with lost data.\n", name);
3611#endif
3612			}
3613		}
3614		else
3615			retval = i;
3616
3617		if (retval < 0) {
3618			if (SRpnt != NULL) {
3619				osst_release_request(SRpnt);
3620				SRpnt = NULL;
3621			}
3622			STp->buffer->buffer_bytes = 0;
3623			STp->dirty = 0;
3624			if (count < total)
3625				retval = total - count;
3626			goto out;
3627		}
3628
3629		*ppos += do_count;
3630		b_point += do_count;
3631		count -= do_count;
3632		if (STps->drv_block >= 0) {
3633			STps->drv_block += blks;
3634		}
3635		STp->buffer->buffer_bytes = 0;
3636		STp->dirty = 0;
3637	}  /* end while write threshold exceeded */
3638
3639	if (count != 0) {
3640		STp->dirty = 1;
3641		i = append_to_buffer(b_point, STp->buffer, count);
3642		if (i) {
3643			retval = i;
3644			goto out;
3645		}
3646		blks = count / STp->block_size;
3647		STp->logical_blk_num += blks;
3648		if (STps->drv_block >= 0) {
3649			STps->drv_block += blks;
3650		}
3651		*ppos += count;
3652		count = 0;
3653	}
3654
3655	if (doing_write && (STp->buffer)->syscall_result != 0) {
3656		retval = (STp->buffer)->syscall_result;
3657		goto out;
3658	}
3659
3660	if (STm->do_async_writes && ((STp->buffer)->buffer_bytes >= STp->write_threshold)) {
3661		/* Schedule an asynchronous write */
3662		(STp->buffer)->writing = ((STp->buffer)->buffer_bytes /
3663					   STp->block_size) * STp->block_size;
3664		STp->dirty = !((STp->buffer)->writing ==
3665				          (STp->buffer)->buffer_bytes);
3666
3667		i = osst_write_frame(STp, &SRpnt, 0);
3668		if (i < 0) {
3669			retval = (-EIO);
3670			goto out;
3671		}
3672		SRpnt = NULL;			/* Prevent releasing this request! */
3673	}
3674	STps->at_sm &= (total == 0);
3675	if (total > 0)
3676		STps->eof = ST_NOEOF;
3677
3678	retval = total;
3679
3680out:
3681	if (SRpnt != NULL) osst_release_request(SRpnt);
3682
3683	mutex_unlock(&STp->lock);
3684
3685	return retval;
3686}
3687
3688
3689/* Read command */
3690static ssize_t osst_read(struct file * filp, char __user * buf, size_t count, loff_t *ppos)
3691{
3692	ssize_t		      total, retval = 0;
3693	ssize_t		      i, transfer;
3694	int		      special;
3695	struct st_modedef   * STm;
3696	struct st_partstat  * STps;
3697	struct osst_request * SRpnt = NULL;
3698	struct osst_tape    * STp   = filp->private_data;
3699	char		    * name  = tape_name(STp);
3700
3701
3702	if (mutex_lock_interruptible(&STp->lock))
3703		return (-ERESTARTSYS);
3704
3705	/*
3706	 * If we are in the middle of error recovery, don't let anyone
3707	 * else try and use this device.  Also, if error recovery fails, it
3708	 * may try and take the device offline, in which case all further
3709	 * access to the device is prohibited.
3710	 */
3711	if( !scsi_block_when_processing_errors(STp->device) ) {
3712		retval = (-ENXIO);
3713		goto out;
3714	}
3715
3716	if (STp->ready != ST_READY) {
3717		if (STp->ready == ST_NO_TAPE)
3718			retval = (-ENOMEDIUM);
3719		else
3720			retval = (-EIO);
3721		goto out;
3722	}
3723	STm = &(STp->modes[STp->current_mode]);
3724	if (!STm->defined) {
3725		retval = (-ENXIO);
3726		goto out;
3727	}
3728#if DEBUG
3729	if (!STp->in_use) {
3730		printk(OSST_DEB_MSG "%s:D: Incorrect device.\n", name);
3731		retval = (-EIO);
3732		goto out;
3733	}
3734#endif
3735	/* Must have initialized medium */
3736	if (!STp->header_ok) {
3737		retval = (-EIO);
3738		goto out;
3739	}
3740
3741	if (STp->do_auto_lock && STp->door_locked == ST_UNLOCKED && !do_door_lock(STp, 1))
3742		STp->door_locked = ST_LOCKED_AUTO;
3743
3744	STps = &(STp->ps[STp->partition]);
3745	if (STps->rw == ST_WRITING) {
3746		retval = osst_flush_buffer(STp, &SRpnt, 0);
3747		if (retval)
3748			goto out;
3749		STps->rw = ST_IDLE;
3750		/* FIXME -- this may leave the tape without EOD and up2date headers */
3751	}
3752
3753	if ((count % STp->block_size) != 0) {
3754		printk(KERN_WARNING
3755		    "%s:W: Read (%Zd bytes) not multiple of tape block size (%d%c).\n", name, count,
3756		    STp->block_size<1024?STp->block_size:STp->block_size/1024, STp->block_size<1024?'b':'k');
3757	}
3758
3759#if DEBUG
3760	if (debugging && STps->eof != ST_NOEOF)
3761		printk(OSST_DEB_MSG "%s:D: EOF/EOM flag up (%d). Bytes %d\n", name,
3762				     STps->eof, (STp->buffer)->buffer_bytes);
3763#endif
3764	if ((STp->buffer)->buffer_bytes == 0 &&
3765	     STps->eof >= ST_EOD_1) {
3766		if (STps->eof < ST_EOD) {
3767			STps->eof += 1;
3768			retval = 0;
3769			goto out;
3770		}
3771		retval = (-EIO);  /* EOM or Blank Check */
3772		goto out;
3773	}
3774
3775	/* Check the buffer writability before any tape movement. Don't alter
3776		 buffer data. */
3777	if (copy_from_user(&i, buf, 1)             != 0 ||
3778	    copy_to_user  (buf, &i, 1)             != 0 ||
3779	    copy_from_user(&i, buf + count - 1, 1) != 0 ||
3780	    copy_to_user  (buf + count - 1, &i, 1) != 0) {
3781		retval = (-EFAULT);
3782		goto out;
3783	}
3784
3785	/* Loop until enough data in buffer or a special condition found */
3786	for (total = 0, special = 0; total < count - STp->block_size + 1 && !special; ) {
3787
3788		/* Get new data if the buffer is empty */
3789		if ((STp->buffer)->buffer_bytes == 0) {
3790			if (STps->eof == ST_FM_HIT)
3791				break;
3792			special = osst_get_logical_frame(STp, &SRpnt, STp->frame_seq_number, 0);
3793			if (special < 0) { 			/* No need to continue read */
3794				STp->frame_in_buffer = 0;
3795				retval = special;
3796				goto out;
3797			}
3798		}
3799
3800		/* Move the data from driver buffer to user buffer */
3801		if ((STp->buffer)->buffer_bytes > 0) {
3802#if DEBUG
3803			if (debugging && STps->eof != ST_NOEOF)
3804			    printk(OSST_DEB_MSG "%s:D: EOF up (%d). Left %d, needed %d.\n", name,
3805						 STps->eof, (STp->buffer)->buffer_bytes, (int) (count - total));
3806#endif
3807		       	/* force multiple of block size, note block_size may have been adjusted */
3808			transfer = (((STp->buffer)->buffer_bytes < count - total ?
3809				     (STp->buffer)->buffer_bytes : count - total)/
3810					STp->block_size) * STp->block_size;
3811
3812			if (transfer == 0) {
3813				printk(KERN_WARNING
3814				  "%s:W: Nothing can be transferred, requested %Zd, tape block size (%d%c).\n",
3815			   		name, count, STp->block_size < 1024?
3816					STp->block_size:STp->block_size/1024,
3817				       	STp->block_size<1024?'b':'k');
3818				break;
3819			}
3820			i = from_buffer(STp->buffer, buf, transfer);
3821			if (i)  {
3822				retval = i;
3823				goto out;
3824			}
3825			STp->logical_blk_num += transfer / STp->block_size;
3826			STps->drv_block      += transfer / STp->block_size;
3827			*ppos          += transfer;
3828			buf                  += transfer;
3829			total                += transfer;
3830		}
3831
3832		if ((STp->buffer)->buffer_bytes == 0) {
3833#if DEBUG
3834			if (debugging)
3835				printk(OSST_DEB_MSG "%s:D: Finished with frame %d\n",
3836					       	name, STp->frame_seq_number);
3837#endif
3838			STp->frame_in_buffer = 0;
3839			STp->frame_seq_number++;              /* frame to look for next time */
3840		}
3841	} /* for (total = 0, special = 0; total < count && !special; ) */
3842
3843	/* Change the eof state if no data from tape or buffer */
3844	if (total == 0) {
3845		if (STps->eof == ST_FM_HIT) {
3846			STps->eof = (STp->first_frame_position >= STp->eod_frame_ppos)?ST_EOD_2:ST_FM;
3847			STps->drv_block = 0;
3848			if (STps->drv_file >= 0)
3849				STps->drv_file++;
3850		}
3851		else if (STps->eof == ST_EOD_1) {
3852			STps->eof = ST_EOD_2;
3853			if (STps->drv_block > 0 && STps->drv_file >= 0)
3854				STps->drv_file++;
3855			STps->drv_block = 0;
3856		}
3857		else if (STps->eof == ST_EOD_2)
3858			STps->eof = ST_EOD;
3859	}
3860	else if (STps->eof == ST_FM)
3861		STps->eof = ST_NOEOF;
3862
3863	retval = total;
3864
3865out:
3866	if (SRpnt != NULL) osst_release_request(SRpnt);
3867
3868	mutex_unlock(&STp->lock);
3869
3870	return retval;
3871}
3872
3873
3874/* Set the driver options */
3875static void osst_log_options(struct osst_tape *STp, struct st_modedef *STm, char *name)
3876{
3877  printk(KERN_INFO
3878"%s:I: Mode %d options: buffer writes: %d, async writes: %d, read ahead: %d\n",
3879	 name, STp->current_mode, STm->do_buffer_writes, STm->do_async_writes,
3880	 STm->do_read_ahead);
3881  printk(KERN_INFO
3882"%s:I:    can bsr: %d, two FMs: %d, fast mteom: %d, auto lock: %d,\n",
3883	 name, STp->can_bsr, STp->two_fm, STp->fast_mteom, STp->do_auto_lock);
3884  printk(KERN_INFO
3885"%s:I:    defs for wr: %d, no block limits: %d, partitions: %d, s2 log: %d\n",
3886	 name, STm->defaults_for_writes, STp->omit_blklims, STp->can_partitions,
3887	 STp->scsi2_logical);
3888  printk(KERN_INFO
3889"%s:I:    sysv: %d\n", name, STm->sysv);
3890#if DEBUG
3891  printk(KERN_INFO
3892	 "%s:D:    debugging: %d\n",
3893	 name, debugging);
3894#endif
3895}
3896
3897
3898static int osst_set_options(struct osst_tape *STp, long options)
3899{
3900	int		    value;
3901	long		    code;
3902	struct st_modedef * STm;
3903	char		  * name = tape_name(STp);
3904
3905	STm = &(STp->modes[STp->current_mode]);
3906	if (!STm->defined) {
3907		memcpy(STm, &(STp->modes[0]), sizeof(*STm));
3908		modes_defined = 1;
3909#if DEBUG
3910		if (debugging)
3911			printk(OSST_DEB_MSG "%s:D: Initialized mode %d definition from mode 0\n",
3912					     name, STp->current_mode);
3913#endif
3914	}
3915
3916	code = options & MT_ST_OPTIONS;
3917	if (code == MT_ST_BOOLEANS) {
3918		STm->do_buffer_writes = (options & MT_ST_BUFFER_WRITES) != 0;
3919		STm->do_async_writes  = (options & MT_ST_ASYNC_WRITES) != 0;
3920		STm->defaults_for_writes = (options & MT_ST_DEF_WRITES) != 0;
3921		STm->do_read_ahead    = (options & MT_ST_READ_AHEAD) != 0;
3922		STp->two_fm	      = (options & MT_ST_TWO_FM) != 0;
3923		STp->fast_mteom	      = (options & MT_ST_FAST_MTEOM) != 0;
3924		STp->do_auto_lock     = (options & MT_ST_AUTO_LOCK) != 0;
3925		STp->can_bsr          = (options & MT_ST_CAN_BSR) != 0;
3926		STp->omit_blklims     = (options & MT_ST_NO_BLKLIMS) != 0;
3927		if ((STp->device)->scsi_level >= SCSI_2)
3928			STp->can_partitions = (options & MT_ST_CAN_PARTITIONS) != 0;
3929		STp->scsi2_logical    = (options & MT_ST_SCSI2LOGICAL) != 0;
3930		STm->sysv	      = (options & MT_ST_SYSV) != 0;
3931#if DEBUG
3932		debugging = (options & MT_ST_DEBUGGING) != 0;
3933#endif
3934		osst_log_options(STp, STm, name);
3935	}
3936	else if (code == MT_ST_SETBOOLEANS || code == MT_ST_CLEARBOOLEANS) {
3937		value = (code == MT_ST_SETBOOLEANS);
3938		if ((options & MT_ST_BUFFER_WRITES) != 0)
3939			STm->do_buffer_writes = value;
3940		if ((options & MT_ST_ASYNC_WRITES) != 0)
3941			STm->do_async_writes = value;
3942		if ((options & MT_ST_DEF_WRITES) != 0)
3943			STm->defaults_for_writes = value;
3944		if ((options & MT_ST_READ_AHEAD) != 0)
3945			STm->do_read_ahead = value;
3946		if ((options & MT_ST_TWO_FM) != 0)
3947			STp->two_fm = value;
3948		if ((options & MT_ST_FAST_MTEOM) != 0)
3949			STp->fast_mteom = value;
3950		if ((options & MT_ST_AUTO_LOCK) != 0)
3951			STp->do_auto_lock = value;
3952		if ((options & MT_ST_CAN_BSR) != 0)
3953			STp->can_bsr = value;
3954		if ((options & MT_ST_NO_BLKLIMS) != 0)
3955			STp->omit_blklims = value;
3956		if ((STp->device)->scsi_level >= SCSI_2 &&
3957		    (options & MT_ST_CAN_PARTITIONS) != 0)
3958			STp->can_partitions = value;
3959		if ((options & MT_ST_SCSI2LOGICAL) != 0)
3960			STp->scsi2_logical = value;
3961		if ((options & MT_ST_SYSV) != 0)
3962			STm->sysv = value;
3963#if DEBUG
3964		if ((options & MT_ST_DEBUGGING) != 0)
3965			debugging = value;
3966#endif
3967		osst_log_options(STp, STm, name);
3968	}
3969	else if (code == MT_ST_WRITE_THRESHOLD) {
3970		value = (options & ~MT_ST_OPTIONS) * ST_KILOBYTE;
3971		if (value < 1 || value > osst_buffer_size) {
3972			printk(KERN_WARNING "%s:W: Write threshold %d too small or too large.\n",
3973					     name, value);
3974			return (-EIO);
3975		}
3976		STp->write_threshold = value;
3977		printk(KERN_INFO "%s:I: Write threshold set to %d bytes.\n",
3978				  name, value);
3979	}
3980	else if (code == MT_ST_DEF_BLKSIZE) {
3981		value = (options & ~MT_ST_OPTIONS);
3982		if (value == ~MT_ST_OPTIONS) {
3983			STm->default_blksize = (-1);
3984			printk(KERN_INFO "%s:I: Default block size disabled.\n", name);
3985		}
3986		else {
3987			if (value < 512 || value > OS_DATA_SIZE || OS_DATA_SIZE % value) {
3988				printk(KERN_WARNING "%s:W: Default block size cannot be set to %d.\n",
3989							 name, value);
3990				return (-EINVAL);
3991			}
3992			STm->default_blksize = value;
3993			printk(KERN_INFO "%s:I: Default block size set to %d bytes.\n",
3994					  name, STm->default_blksize);
3995		}
3996	}
3997	else if (code == MT_ST_TIMEOUTS) {
3998		value = (options & ~MT_ST_OPTIONS);
3999		if ((value & MT_ST_SET_LONG_TIMEOUT) != 0) {
4000			STp->long_timeout = (value & ~MT_ST_SET_LONG_TIMEOUT) * HZ;
4001			printk(KERN_INFO "%s:I: Long timeout set to %d seconds.\n", name,
4002					     (value & ~MT_ST_SET_LONG_TIMEOUT));
4003		}
4004		else {
4005			STp->timeout = value * HZ;
4006			printk(KERN_INFO "%s:I: Normal timeout set to %d seconds.\n", name, value);
4007		}
4008	}
4009	else if (code == MT_ST_DEF_OPTIONS) {
4010		code = (options & ~MT_ST_CLEAR_DEFAULT);
4011		value = (options & MT_ST_CLEAR_DEFAULT);
4012		if (code == MT_ST_DEF_DENSITY) {
4013			if (value == MT_ST_CLEAR_DEFAULT) {
4014				STm->default_density = (-1);
4015				printk(KERN_INFO "%s:I: Density default disabled.\n", name);
4016			}
4017			else {
4018				STm->default_density = value & 0xff;
4019				printk(KERN_INFO "%s:I: Density default set to %x\n",
4020						  name, STm->default_density);
4021			}
4022		}
4023		else if (code == MT_ST_DEF_DRVBUFFER) {
4024			if (value == MT_ST_CLEAR_DEFAULT) {
4025				STp->default_drvbuffer = 0xff;
4026				printk(KERN_INFO "%s:I: Drive buffer default disabled.\n", name);
4027			}
4028			else {
4029				STp->default_drvbuffer = value & 7;
4030				printk(KERN_INFO "%s:I: Drive buffer default set to %x\n",
4031						  name, STp->default_drvbuffer);
4032			}
4033		}
4034		else if (code == MT_ST_DEF_COMPRESSION) {
4035			if (value == MT_ST_CLEAR_DEFAULT) {
4036				STm->default_compression = ST_DONT_TOUCH;
4037				printk(KERN_INFO "%s:I: Compression default disabled.\n", name);
4038			}
4039			else {
4040				STm->default_compression = (value & 1 ? ST_YES : ST_NO);
4041				printk(KERN_INFO "%s:I: Compression default set to %x\n",
4042						  name, (value & 1));
4043			}
4044		}
4045	}
4046	else
4047		return (-EIO);
4048
4049	return 0;
4050}
4051
4052
4053/* Internal ioctl function */
4054static int osst_int_ioctl(struct osst_tape * STp, struct osst_request ** aSRpnt,
4055			     unsigned int cmd_in, unsigned long arg)
4056{
4057	int			timeout;
4058	long			ltmp;
4059	int			i, ioctl_result;
4060	int			chg_eof = 1;
4061	unsigned char		cmd[MAX_COMMAND_SIZE];
4062	struct osst_request   * SRpnt = * aSRpnt;
4063	struct st_partstat    * STps;
4064	int			fileno, blkno, at_sm, frame_seq_numbr, logical_blk_num;
4065	int			datalen = 0, direction = DMA_NONE;
4066	char		      * name = tape_name(STp);
4067
4068	if (STp->ready != ST_READY && cmd_in != MTLOAD) {
4069		if (STp->ready == ST_NO_TAPE)
4070			return (-ENOMEDIUM);
4071		else
4072			return (-EIO);
4073	}
4074	timeout = STp->long_timeout;
4075	STps = &(STp->ps[STp->partition]);
4076	fileno = STps->drv_file;
4077	blkno = STps->drv_block;
4078	at_sm = STps->at_sm;
4079	frame_seq_numbr = STp->frame_seq_number;
4080	logical_blk_num = STp->logical_blk_num;
4081
4082	memset(cmd, 0, MAX_COMMAND_SIZE);
4083	switch (cmd_in) {
4084	 case MTFSFM:
4085		chg_eof = 0; /* Changed from the FSF after this */
4086	 case MTFSF:
4087		if (STp->raw)
4088		   return (-EIO);
4089		if (STp->linux_media)
4090		   ioctl_result = osst_space_over_filemarks_forward_fast(STp, &SRpnt, cmd_in, arg);
4091		else
4092		   ioctl_result = osst_space_over_filemarks_forward_slow(STp, &SRpnt, cmd_in, arg);
4093		if (fileno >= 0)
4094		   fileno += arg;
4095		blkno = 0;
4096		at_sm &= (arg == 0);
4097		goto os_bypass;
4098
4099	 case MTBSF:
4100		chg_eof = 0; /* Changed from the FSF after this */
4101	 case MTBSFM:
4102		if (STp->raw)
4103		   return (-EIO);
4104		ioctl_result = osst_space_over_filemarks_backward(STp, &SRpnt, cmd_in, arg);
4105		if (fileno >= 0)
4106		   fileno -= arg;
4107		blkno = (-1);  /* We can't know the block number */
4108		at_sm &= (arg == 0);
4109		goto os_bypass;
4110
4111	 case MTFSR:
4112	 case MTBSR:
4113#if DEBUG
4114		if (debugging)
4115		   printk(OSST_DEB_MSG "%s:D: Skipping %lu blocks %s from logical block %d\n",
4116				name, arg, cmd_in==MTFSR?"forward":"backward", logical_blk_num);
4117#endif
4118		if (cmd_in == MTFSR) {
4119		   logical_blk_num += arg;
4120		   if (blkno >= 0) blkno += arg;
4121		}
4122		else {
4123		   logical_blk_num -= arg;
4124		   if (blkno >= 0) blkno -= arg;
4125		}
4126		ioctl_result = osst_seek_logical_blk(STp, &SRpnt, logical_blk_num);
4127		fileno = STps->drv_file;
4128		blkno  = STps->drv_block;
4129		at_sm &= (arg == 0);
4130		goto os_bypass;
4131
4132	 case MTFSS:
4133		cmd[0] = SPACE;
4134		cmd[1] = 0x04; /* Space Setmarks */   /* FIXME -- OS can't do this? */
4135		cmd[2] = (arg >> 16);
4136		cmd[3] = (arg >> 8);
4137		cmd[4] = arg;
4138#if DEBUG
4139		if (debugging)
4140			printk(OSST_DEB_MSG "%s:D: Spacing tape forward %d setmarks.\n", name,
4141		cmd[2] * 65536 + cmd[3] * 256 + cmd[4]);
4142#endif
4143		if (arg != 0) {
4144			blkno = fileno = (-1);
4145			at_sm = 1;
4146		}
4147		break;
4148	 case MTBSS:
4149		cmd[0] = SPACE;
4150		cmd[1] = 0x04; /* Space Setmarks */   /* FIXME -- OS can't do this? */
4151		ltmp = (-arg);
4152		cmd[2] = (ltmp >> 16);
4153		cmd[3] = (ltmp >> 8);
4154		cmd[4] = ltmp;
4155#if DEBUG
4156		if (debugging) {
4157			if (cmd[2] & 0x80)
4158			   ltmp = 0xff000000;
4159			ltmp = ltmp | (cmd[2] << 16) | (cmd[3] << 8) | cmd[4];
4160			printk(OSST_DEB_MSG "%s:D: Spacing tape backward %ld setmarks.\n",
4161						name, (-ltmp));
4162		 }
4163#endif
4164		 if (arg != 0) {
4165			blkno = fileno = (-1);
4166			at_sm = 1;
4167		 }
4168		 break;
4169	 case MTWEOF:
4170		 if ((STps->rw == ST_WRITING || STp->dirty) && !STp->pos_unknown) {
4171			STp->write_type = OS_WRITE_DATA;
4172			ioctl_result = osst_flush_write_buffer(STp, &SRpnt);
4173		 } else
4174			ioctl_result = 0;
4175#if DEBUG
4176		 if (debugging)
4177			   printk(OSST_DEB_MSG "%s:D: Writing %ld filemark(s).\n", name, arg);
4178#endif
4179		 for (i=0; i<arg; i++)
4180			ioctl_result |= osst_write_filemark(STp, &SRpnt);
4181		 if (fileno >= 0) fileno += arg;
4182		 if (blkno  >= 0) blkno   = 0;
4183		 goto os_bypass;
4184
4185	 case MTWSM:
4186		 if (STp->write_prot)
4187			return (-EACCES);
4188		 if (!STp->raw)
4189			return 0;
4190		 cmd[0] = WRITE_FILEMARKS;   /* FIXME -- need OS version */
4191		 if (cmd_in == MTWSM)
4192			 cmd[1] = 2;
4193		 cmd[2] = (arg >> 16);
4194		 cmd[3] = (arg >> 8);
4195		 cmd[4] = arg;
4196		 timeout = STp->timeout;
4197#if DEBUG
4198		 if (debugging)
4199			   printk(OSST_DEB_MSG "%s:D: Writing %d setmark(s).\n", name,
4200				  cmd[2] * 65536 + cmd[3] * 256 + cmd[4]);
4201#endif
4202		 if (fileno >= 0)
4203			fileno += arg;
4204		 blkno = 0;
4205		 at_sm = (cmd_in == MTWSM);
4206		 break;
4207	 case MTOFFL:
4208	 case MTLOAD:
4209	 case MTUNLOAD:
4210	 case MTRETEN:
4211		 cmd[0] = START_STOP;
4212		 cmd[1] = 1;			/* Don't wait for completion */
4213		 if (cmd_in == MTLOAD) {
4214		     if (STp->ready == ST_NO_TAPE)
4215			 cmd[4] = 4;		/* open tray */
4216		      else
4217			 cmd[4] = 1;		/* load */
4218		 }
4219		 if (cmd_in == MTRETEN)
4220			 cmd[4] = 3;		/* retension then mount */
4221		 if (cmd_in == MTOFFL)
4222			 cmd[4] = 4;		/* rewind then eject */
4223		 timeout = STp->timeout;
4224#if DEBUG
4225		 if (debugging) {
4226			 switch (cmd_in) {
4227				 case MTUNLOAD:
4228					 printk(OSST_DEB_MSG "%s:D: Unloading tape.\n", name);
4229					 break;
4230				 case MTLOAD:
4231					 printk(OSST_DEB_MSG "%s:D: Loading tape.\n", name);
4232					 break;
4233				 case MTRETEN:
4234					 printk(OSST_DEB_MSG "%s:D: Retensioning tape.\n", name);
4235					 break;
4236				 case MTOFFL:
4237					 printk(OSST_DEB_MSG "%s:D: Ejecting tape.\n", name);
4238					 break;
4239			 }
4240		 }
4241#endif
4242       fileno = blkno = at_sm = frame_seq_numbr = logical_blk_num = 0 ;
4243		 break;
4244	 case MTNOP:
4245#if DEBUG
4246		 if (debugging)
4247			 printk(OSST_DEB_MSG "%s:D: No-op on tape.\n", name);
4248#endif
4249		 return 0;  /* Should do something ? */
4250		 break;
4251	 case MTEOM:
4252#if DEBUG
4253		if (debugging)
4254		   printk(OSST_DEB_MSG "%s:D: Spacing to end of recorded medium.\n", name);
4255#endif
4256		if ((osst_position_tape_and_confirm(STp, &SRpnt, STp->eod_frame_ppos) < 0) ||
4257			    (osst_get_logical_frame(STp, &SRpnt, -1, 0)               < 0)) {
4258		   ioctl_result = -EIO;
4259		   goto os_bypass;
4260		}
4261		if (STp->buffer->aux->frame_type != OS_FRAME_TYPE_EOD) {
4262#if DEBUG
4263		   printk(OSST_DEB_MSG "%s:D: No EOD frame found where expected.\n", name);
4264#endif
4265		   ioctl_result = -EIO;
4266		   goto os_bypass;
4267		}
4268		ioctl_result = osst_set_frame_position(STp, &SRpnt, STp->eod_frame_ppos, 0);
4269		fileno = STp->filemark_cnt;
4270		blkno  = at_sm = 0;
4271		goto os_bypass;
4272
4273	 case MTERASE:
4274		if (STp->write_prot)
4275		   return (-EACCES);
4276		ioctl_result = osst_reset_header(STp, &SRpnt);
4277		i = osst_write_eod(STp, &SRpnt);
4278		if (i < ioctl_result) ioctl_result = i;
4279		i = osst_position_tape_and_confirm(STp, &SRpnt, STp->eod_frame_ppos);
4280		if (i < ioctl_result) ioctl_result = i;
4281		fileno = blkno = at_sm = 0 ;
4282		goto os_bypass;
4283
4284	 case MTREW:
4285		cmd[0] = REZERO_UNIT; /* rewind */
4286		cmd[1] = 1;
4287#if DEBUG
4288		if (debugging)
4289		   printk(OSST_DEB_MSG "%s:D: Rewinding tape, Immed=%d.\n", name, cmd[1]);
4290#endif
4291		fileno = blkno = at_sm = frame_seq_numbr = logical_blk_num = 0 ;
4292		break;
4293
4294	 case MTSETBLK:           /* Set block length */
4295		 if ((STps->drv_block == 0 )			  &&
4296		     !STp->dirty				  &&
4297		     ((STp->buffer)->buffer_bytes == 0)		  &&
4298		     ((arg & MT_ST_BLKSIZE_MASK) >= 512 )	  &&
4299		     ((arg & MT_ST_BLKSIZE_MASK) <= OS_DATA_SIZE) &&
4300		     !(OS_DATA_SIZE % (arg & MT_ST_BLKSIZE_MASK))  ) {
4301			 /*
4302			  * Only allowed to change the block size if you opened the
4303			  * device at the beginning of a file before writing anything.
4304			  * Note, that when reading, changing block_size is futile,
4305			  * as the size used when writing overrides it.
4306			  */
4307			 STp->block_size = (arg & MT_ST_BLKSIZE_MASK);
4308			 printk(KERN_INFO "%s:I: Block size set to %d bytes.\n",
4309					   name, STp->block_size);
4310			 return 0;
4311		 }
4312	 case MTSETDENSITY:       /* Set tape density */
4313	 case MTSETDRVBUFFER:     /* Set drive buffering */
4314	 case SET_DENS_AND_BLK:   /* Set density and block size */
4315		 chg_eof = 0;
4316		 if (STp->dirty || (STp->buffer)->buffer_bytes != 0)
4317			 return (-EIO);       /* Not allowed if data in buffer */
4318		 if ((cmd_in == MTSETBLK || cmd_in == SET_DENS_AND_BLK) &&
4319		     (arg & MT_ST_BLKSIZE_MASK) != 0                    &&
4320		     (arg & MT_ST_BLKSIZE_MASK) != STp->block_size       ) {
4321			 printk(KERN_WARNING "%s:W: Illegal to set block size to %d%s.\n",
4322						name, (int)(arg & MT_ST_BLKSIZE_MASK),
4323						(OS_DATA_SIZE % (arg & MT_ST_BLKSIZE_MASK))?"":" now");
4324			 return (-EINVAL);
4325		 }
4326		 return 0;  /* FIXME silently ignore if block size didn't change */
4327
4328	 default:
4329		return (-ENOSYS);
4330	}
4331
4332	SRpnt = osst_do_scsi(SRpnt, STp, cmd, datalen, direction, timeout, MAX_RETRIES, 1);
4333
4334	ioctl_result = (STp->buffer)->syscall_result;
4335
4336	if (!SRpnt) {
4337#if DEBUG
4338		printk(OSST_DEB_MSG "%s:D: Couldn't exec scsi cmd for IOCTL\n", name);
4339#endif
4340		return ioctl_result;
4341	}
4342
4343	if (!ioctl_result) {  /* SCSI command successful */
4344		STp->frame_seq_number = frame_seq_numbr;
4345		STp->logical_blk_num  = logical_blk_num;
4346	}
4347
4348os_bypass:
4349#if DEBUG
4350	if (debugging)
4351		printk(OSST_DEB_MSG "%s:D: IOCTL (%d) Result=%d\n", name, cmd_in, ioctl_result);
4352#endif
4353
4354	if (!ioctl_result) {				/* success */
4355
4356		if (cmd_in == MTFSFM) {
4357			 fileno--;
4358			 blkno--;
4359		}
4360		if (cmd_in == MTBSFM) {
4361			 fileno++;
4362			 blkno++;
4363		}
4364		STps->drv_block = blkno;
4365		STps->drv_file = fileno;
4366		STps->at_sm = at_sm;
4367
4368		if (cmd_in == MTEOM)
4369			STps->eof = ST_EOD;
4370		else if ((cmd_in == MTFSFM || cmd_in == MTBSF) && STps->eof == ST_FM_HIT) {
4371			ioctl_result = osst_seek_logical_blk(STp, &SRpnt, STp->logical_blk_num-1);
4372			STps->drv_block++;
4373			STp->logical_blk_num++;
4374			STp->frame_seq_number++;
4375			STp->frame_in_buffer = 0;
4376			STp->buffer->read_pointer = 0;
4377		}
4378		else if (cmd_in == MTFSF)
4379			STps->eof = (STp->first_frame_position >= STp->eod_frame_ppos)?ST_EOD:ST_FM;
4380		else if (chg_eof)
4381			STps->eof = ST_NOEOF;
4382
4383		if (cmd_in == MTOFFL || cmd_in == MTUNLOAD)
4384			STp->rew_at_close = 0;
4385		else if (cmd_in == MTLOAD) {
4386			for (i=0; i < ST_NBR_PARTITIONS; i++) {
4387			    STp->ps[i].rw = ST_IDLE;
4388			    STp->ps[i].last_block_valid = 0;/* FIXME - where else is this field maintained? */
4389			}
4390			STp->partition = 0;
4391		}
4392
4393		if (cmd_in == MTREW) {
4394			ioctl_result = osst_position_tape_and_confirm(STp, &SRpnt, STp->first_data_ppos);
4395			if (ioctl_result > 0)
4396				ioctl_result = 0;
4397		}
4398
4399	} else if (cmd_in == MTBSF || cmd_in == MTBSFM ) {
4400		if (osst_position_tape_and_confirm(STp, &SRpnt, STp->first_data_ppos) < 0)
4401			STps->drv_file = STps->drv_block = -1;
4402		else
4403			STps->drv_file = STps->drv_block = 0;
4404		STps->eof = ST_NOEOF;
4405	} else if (cmd_in == MTFSF || cmd_in == MTFSFM) {
4406		if (osst_position_tape_and_confirm(STp, &SRpnt, STp->eod_frame_ppos) < 0)
4407			STps->drv_file = STps->drv_block = -1;
4408		else {
4409			STps->drv_file  = STp->filemark_cnt;
4410			STps->drv_block = 0;
4411		}
4412		STps->eof = ST_EOD;
4413	} else if (cmd_in == MTBSR || cmd_in == MTFSR || cmd_in == MTWEOF || cmd_in == MTEOM) {
4414		STps->drv_file = STps->drv_block = (-1);
4415		STps->eof = ST_NOEOF;
4416		STp->header_ok = 0;
4417	} else if (cmd_in == MTERASE) {
4418		STp->header_ok = 0;
4419	} else if (SRpnt) {  /* SCSI command was not completely successful. */
4420		if (SRpnt->sense[2] & 0x40) {
4421			STps->eof = ST_EOM_OK;
4422			STps->drv_block = 0;
4423		}
4424		if (chg_eof)
4425			STps->eof = ST_NOEOF;
4426
4427		if ((SRpnt->sense[2] & 0x0f) == BLANK_CHECK)
4428			STps->eof = ST_EOD;
4429
4430		if (cmd_in == MTLOAD && osst_wait_for_medium(STp, &SRpnt, 60))
4431			ioctl_result = osst_wait_ready(STp, &SRpnt, 5 * 60, OSST_WAIT_POSITION_COMPLETE);
4432	}
4433	*aSRpnt = SRpnt;
4434
4435	return ioctl_result;
4436}
4437
4438
4439/* Open the device */
4440static int __os_scsi_tape_open(struct inode * inode, struct file * filp)
4441{
4442	unsigned short	      flags;
4443	int		      i, b_size, new_session = 0, retval = 0;
4444	unsigned char	      cmd[MAX_COMMAND_SIZE];
4445	struct osst_request * SRpnt = NULL;
4446	struct osst_tape    * STp;
4447	struct st_modedef   * STm;
4448	struct st_partstat  * STps;
4449	char		    * name;
4450	int		      dev  = TAPE_NR(inode);
4451	int		      mode = TAPE_MODE(inode);
4452
4453	/*
4454	 * We really want to do nonseekable_open(inode, filp); here, but some
4455	 * versions of tar incorrectly call lseek on tapes and bail out if that
4456	 * fails.  So we disallow pread() and pwrite(), but permit lseeks.
4457	 */
4458	filp->f_mode &= ~(FMODE_PREAD | FMODE_PWRITE);
4459
4460	write_lock(&os_scsi_tapes_lock);
4461	if (dev >= osst_max_dev || os_scsi_tapes == NULL ||
4462	    (STp = os_scsi_tapes[dev]) == NULL || !STp->device) {
4463		write_unlock(&os_scsi_tapes_lock);
4464		return (-ENXIO);
4465	}
4466
4467	name = tape_name(STp);
4468
4469	if (STp->in_use) {
4470		write_unlock(&os_scsi_tapes_lock);
4471#if DEBUG
4472		printk(OSST_DEB_MSG "%s:D: Device already in use.\n", name);
4473#endif
4474		return (-EBUSY);
4475	}
4476	if (scsi_device_get(STp->device)) {
4477		write_unlock(&os_scsi_tapes_lock);
4478#if DEBUG
4479                printk(OSST_DEB_MSG "%s:D: Failed scsi_device_get.\n", name);
4480#endif
4481		return (-ENXIO);
4482	}
4483	filp->private_data = STp;
4484	STp->in_use = 1;
4485	write_unlock(&os_scsi_tapes_lock);
4486	STp->rew_at_close = TAPE_REWIND(inode);
4487
4488	if( !scsi_block_when_processing_errors(STp->device) ) {
4489		return -ENXIO;
4490	}
4491
4492	if (mode != STp->current_mode) {
4493#if DEBUG
4494		if (debugging)
4495			printk(OSST_DEB_MSG "%s:D: Mode change from %d to %d.\n",
4496					       name, STp->current_mode, mode);
4497#endif
4498		new_session = 1;
4499		STp->current_mode = mode;
4500	}
4501	STm = &(STp->modes[STp->current_mode]);
4502
4503	flags = filp->f_flags;
4504	STp->write_prot = ((flags & O_ACCMODE) == O_RDONLY);
4505
4506	STp->raw = TAPE_IS_RAW(inode);
4507	if (STp->raw)
4508		STp->header_ok = 0;
4509
4510	/* Allocate data segments for this device's tape buffer */
4511	if (!enlarge_buffer(STp->buffer, STp->restr_dma)) {
4512		printk(KERN_ERR "%s:E: Unable to allocate memory segments for tape buffer.\n", name);
4513		retval = (-EOVERFLOW);
4514		goto err_out;
4515	}
4516	if (STp->buffer->buffer_size >= OS_FRAME_SIZE) {
4517		for (i = 0, b_size = 0;
4518		     (i < STp->buffer->sg_segs) && ((b_size + STp->buffer->sg[i].length) <= OS_DATA_SIZE);
4519		     b_size += STp->buffer->sg[i++].length);
4520		STp->buffer->aux = (os_aux_t *) (page_address(sg_page(&STp->buffer->sg[i])) + OS_DATA_SIZE - b_size);
4521#if DEBUG
4522		printk(OSST_DEB_MSG "%s:D: b_data points to %p in segment 0 at %p\n", name,
4523			STp->buffer->b_data, page_address(STp->buffer->sg[0].page));
4524		printk(OSST_DEB_MSG "%s:D: AUX points to %p in segment %d at %p\n", name,
4525			 STp->buffer->aux, i, page_address(STp->buffer->sg[i].page));
4526#endif
4527	} else {
4528		STp->buffer->aux = NULL; /* this had better never happen! */
4529		printk(KERN_NOTICE "%s:A: Framesize %d too large for buffer.\n", name, OS_FRAME_SIZE);
4530		retval = (-EIO);
4531		goto err_out;
4532	}
4533	STp->buffer->writing = 0;
4534	STp->buffer->syscall_result = 0;
4535	STp->dirty = 0;
4536	for (i=0; i < ST_NBR_PARTITIONS; i++) {
4537		STps = &(STp->ps[i]);
4538		STps->rw = ST_IDLE;
4539	}
4540	STp->ready = ST_READY;
4541#if DEBUG
4542	STp->nbr_waits = STp->nbr_finished = 0;
4543#endif
4544
4545	memset (cmd, 0, MAX_COMMAND_SIZE);
4546	cmd[0] = TEST_UNIT_READY;
4547
4548	SRpnt = osst_do_scsi(NULL, STp, cmd, 0, DMA_NONE, STp->timeout, MAX_RETRIES, 1);
4549	if (!SRpnt) {
4550		retval = (STp->buffer)->syscall_result;		/* FIXME - valid? */
4551		goto err_out;
4552	}
4553	if ((SRpnt->sense[0] & 0x70) == 0x70      &&
4554	    (SRpnt->sense[2] & 0x0f) == NOT_READY &&
4555	     SRpnt->sense[12]        == 4         ) {
4556#if DEBUG
4557		printk(OSST_DEB_MSG "%s:D: Unit not ready, cause %x\n", name, SRpnt->sense[13]);
4558#endif
4559		if (filp->f_flags & O_NONBLOCK) {
4560			retval = -EAGAIN;
4561			goto err_out;
4562		}
4563		if (SRpnt->sense[13] == 2) {	/* initialize command required (LOAD) */
4564			memset (cmd, 0, MAX_COMMAND_SIZE);
4565        		cmd[0] = START_STOP;
4566			cmd[1] = 1;
4567			cmd[4] = 1;
4568			SRpnt = osst_do_scsi(SRpnt, STp, cmd, 0, DMA_NONE,
4569					     STp->timeout, MAX_RETRIES, 1);
4570		}
4571		osst_wait_ready(STp, &SRpnt, (SRpnt->sense[13]==1?15:3) * 60, 0);
4572	}
4573	if ((SRpnt->sense[0] & 0x70) == 0x70 &&
4574	    (SRpnt->sense[2] & 0x0f) == UNIT_ATTENTION) { /* New media? */
4575#if DEBUG
4576		printk(OSST_DEB_MSG "%s:D: Unit wants attention\n", name);
4577#endif
4578		STp->header_ok = 0;
4579
4580		for (i=0; i < 10; i++) {
4581
4582			memset (cmd, 0, MAX_COMMAND_SIZE);
4583			cmd[0] = TEST_UNIT_READY;
4584
4585			SRpnt = osst_do_scsi(SRpnt, STp, cmd, 0, DMA_NONE,
4586					     STp->timeout, MAX_RETRIES, 1);
4587			if ((SRpnt->sense[0] & 0x70) != 0x70 ||
4588			    (SRpnt->sense[2] & 0x0f) != UNIT_ATTENTION)
4589				break;
4590		}
4591
4592		STp->pos_unknown = 0;
4593		STp->partition = STp->new_partition = 0;
4594		if (STp->can_partitions)
4595			STp->nbr_partitions = 1;  /* This guess will be updated later if necessary */
4596		for (i=0; i < ST_NBR_PARTITIONS; i++) {
4597			STps = &(STp->ps[i]);
4598			STps->rw = ST_IDLE;		/* FIXME - seems to be redundant... */
4599			STps->eof = ST_NOEOF;
4600			STps->at_sm = 0;
4601			STps->last_block_valid = 0;
4602			STps->drv_block = 0;
4603			STps->drv_file = 0 ;
4604		}
4605		new_session = 1;
4606		STp->recover_count = 0;
4607		STp->abort_count = 0;
4608	}
4609	/*
4610	 * if we have valid headers from before, and the drive/tape seem untouched,
4611	 * open without reconfiguring and re-reading the headers
4612	 */
4613	if (!STp->buffer->syscall_result && STp->header_ok &&
4614	    !SRpnt->result && SRpnt->sense[0] == 0) {
4615
4616		memset(cmd, 0, MAX_COMMAND_SIZE);
4617		cmd[0] = MODE_SENSE;
4618		cmd[1] = 8;
4619		cmd[2] = VENDOR_IDENT_PAGE;
4620		cmd[4] = VENDOR_IDENT_PAGE_LENGTH + MODE_HEADER_LENGTH;
4621
4622		SRpnt = osst_do_scsi(SRpnt, STp, cmd, cmd[4], DMA_FROM_DEVICE, STp->timeout, 0, 1);
4623
4624		if (STp->buffer->syscall_result                     ||
4625		    STp->buffer->b_data[MODE_HEADER_LENGTH + 2] != 'L' ||
4626		    STp->buffer->b_data[MODE_HEADER_LENGTH + 3] != 'I' ||
4627		    STp->buffer->b_data[MODE_HEADER_LENGTH + 4] != 'N' ||
4628		    STp->buffer->b_data[MODE_HEADER_LENGTH + 5] != '4'  ) {
4629#if DEBUG
4630			printk(OSST_DEB_MSG "%s:D: Signature was changed to %c%c%c%c\n", name,
4631			  STp->buffer->b_data[MODE_HEADER_LENGTH + 2],
4632			  STp->buffer->b_data[MODE_HEADER_LENGTH + 3],
4633			  STp->buffer->b_data[MODE_HEADER_LENGTH + 4],
4634			  STp->buffer->b_data[MODE_HEADER_LENGTH + 5]);
4635#endif
4636			STp->header_ok = 0;
4637		}
4638		i = STp->first_frame_position;
4639		if (STp->header_ok && i == osst_get_frame_position(STp, &SRpnt)) {
4640			if (STp->door_locked == ST_UNLOCKED) {
4641				if (do_door_lock(STp, 1))
4642					printk(KERN_INFO "%s:I: Can't lock drive door\n", name);
4643				else
4644					STp->door_locked = ST_LOCKED_AUTO;
4645			}
4646			if (!STp->frame_in_buffer) {
4647				STp->block_size = (STm->default_blksize > 0) ?
4648							STm->default_blksize : OS_DATA_SIZE;
4649				STp->buffer->buffer_bytes = STp->buffer->read_pointer = 0;
4650			}
4651			STp->buffer->buffer_blocks = OS_DATA_SIZE / STp->block_size;
4652			STp->fast_open = 1;
4653			osst_release_request(SRpnt);
4654			return 0;
4655		}
4656#if DEBUG
4657		if (i != STp->first_frame_position)
4658			printk(OSST_DEB_MSG "%s:D: Tape position changed from %d to %d\n",
4659						name, i, STp->first_frame_position);
4660#endif
4661		STp->header_ok = 0;
4662	}
4663	STp->fast_open = 0;
4664
4665	if ((STp->buffer)->syscall_result != 0 &&   /* in all error conditions except no medium */
4666	    (SRpnt->sense[2] != 2 || SRpnt->sense[12] != 0x3A) ) {
4667
4668		memset(cmd, 0, MAX_COMMAND_SIZE);
4669		cmd[0] = MODE_SELECT;
4670		cmd[1] = 0x10;
4671		cmd[4] = 4 + MODE_HEADER_LENGTH;
4672
4673		(STp->buffer)->b_data[0] = cmd[4] - 1;
4674		(STp->buffer)->b_data[1] = 0;			/* Medium Type - ignoring */
4675		(STp->buffer)->b_data[2] = 0;			/* Reserved */
4676		(STp->buffer)->b_data[3] = 0;			/* Block Descriptor Length */
4677		(STp->buffer)->b_data[MODE_HEADER_LENGTH + 0] = 0x3f;
4678		(STp->buffer)->b_data[MODE_HEADER_LENGTH + 1] = 1;
4679		(STp->buffer)->b_data[MODE_HEADER_LENGTH + 2] = 2;
4680		(STp->buffer)->b_data[MODE_HEADER_LENGTH + 3] = 3;
4681
4682#if DEBUG
4683		printk(OSST_DEB_MSG "%s:D: Applying soft reset\n", name);
4684#endif
4685		SRpnt = osst_do_scsi(SRpnt, STp, cmd, cmd[4], DMA_TO_DEVICE, STp->timeout, 0, 1);
4686
4687		STp->header_ok = 0;
4688
4689		for (i=0; i < 10; i++) {
4690
4691			memset (cmd, 0, MAX_COMMAND_SIZE);
4692			cmd[0] = TEST_UNIT_READY;
4693
4694			SRpnt = osst_do_scsi(SRpnt, STp, cmd, 0, DMA_NONE,
4695						    STp->timeout, MAX_RETRIES, 1);
4696			if ((SRpnt->sense[0] & 0x70) != 0x70 ||
4697			    (SRpnt->sense[2] & 0x0f) == NOT_READY)
4698			break;
4699
4700			if ((SRpnt->sense[2] & 0x0f) == UNIT_ATTENTION) {
4701				STp->pos_unknown = 0;
4702				STp->partition = STp->new_partition = 0;
4703				if (STp->can_partitions)
4704					STp->nbr_partitions = 1;  /* This guess will be updated later if necessary */
4705				for (i=0; i < ST_NBR_PARTITIONS; i++) {
4706					STps = &(STp->ps[i]);
4707					STps->rw = ST_IDLE;
4708					STps->eof = ST_NOEOF;
4709					STps->at_sm = 0;
4710					STps->last_block_valid = 0;
4711					STps->drv_block = 0;
4712					STps->drv_file = 0 ;
4713				}
4714				new_session = 1;
4715			}
4716		}
4717	}
4718
4719	if (osst_wait_ready(STp, &SRpnt, 15 * 60, 0))		/* FIXME - not allowed with NOBLOCK */
4720		 printk(KERN_INFO "%s:I: Device did not become Ready in open\n", name);
4721
4722	if ((STp->buffer)->syscall_result != 0) {
4723		if ((STp->device)->scsi_level >= SCSI_2 &&
4724		    (SRpnt->sense[0] & 0x70) == 0x70 &&
4725		    (SRpnt->sense[2] & 0x0f) == NOT_READY &&
4726		     SRpnt->sense[12] == 0x3a) { /* Check ASC */
4727			STp->ready = ST_NO_TAPE;
4728		} else
4729			STp->ready = ST_NOT_READY;
4730		osst_release_request(SRpnt);
4731		SRpnt = NULL;
4732		STp->density = 0;   	/* Clear the erroneous "residue" */
4733		STp->write_prot = 0;
4734		STp->block_size = 0;
4735		STp->ps[0].drv_file = STp->ps[0].drv_block = (-1);
4736		STp->partition = STp->new_partition = 0;
4737		STp->door_locked = ST_UNLOCKED;
4738		return 0;
4739	}
4740
4741	osst_configure_onstream(STp, &SRpnt);
4742
4743	STp->block_size = STp->raw ? OS_FRAME_SIZE : (
4744			     (STm->default_blksize > 0) ? STm->default_blksize : OS_DATA_SIZE);
4745	STp->buffer->buffer_blocks = STp->raw ? 1 : OS_DATA_SIZE / STp->block_size;
4746	STp->buffer->buffer_bytes  =
4747	STp->buffer->read_pointer  =
4748	STp->frame_in_buffer       = 0;
4749
4750#if DEBUG
4751	if (debugging)
4752		printk(OSST_DEB_MSG "%s:D: Block size: %d, frame size: %d, buffer size: %d (%d blocks).\n",
4753		     name, STp->block_size, OS_FRAME_SIZE, (STp->buffer)->buffer_size,
4754		     (STp->buffer)->buffer_blocks);
4755#endif
4756
4757	if (STp->drv_write_prot) {
4758		STp->write_prot = 1;
4759#if DEBUG
4760		if (debugging)
4761			printk(OSST_DEB_MSG "%s:D: Write protected\n", name);
4762#endif
4763		if ((flags & O_ACCMODE) == O_WRONLY || (flags & O_ACCMODE) == O_RDWR) {
4764			retval = (-EROFS);
4765			goto err_out;
4766		}
4767	}
4768
4769	if (new_session) {  /* Change the drive parameters for the new mode */
4770#if DEBUG
4771		if (debugging)
4772	printk(OSST_DEB_MSG "%s:D: New Session\n", name);
4773#endif
4774		STp->density_changed = STp->blksize_changed = 0;
4775		STp->compression_changed = 0;
4776	}
4777
4778	/*
4779	 * properly position the tape and check the ADR headers
4780	 */
4781	if (STp->door_locked == ST_UNLOCKED) {
4782		 if (do_door_lock(STp, 1))
4783			printk(KERN_INFO "%s:I: Can't lock drive door\n", name);
4784		 else
4785			STp->door_locked = ST_LOCKED_AUTO;
4786	}
4787
4788	osst_analyze_headers(STp, &SRpnt);
4789
4790	osst_release_request(SRpnt);
4791	SRpnt = NULL;
4792
4793	return 0;
4794
4795err_out:
4796	if (SRpnt != NULL)
4797		osst_release_request(SRpnt);
4798	normalize_buffer(STp->buffer);
4799	STp->header_ok = 0;
4800	STp->in_use = 0;
4801	scsi_device_put(STp->device);
4802
4803	return retval;
4804}
4805
4806/* BKL pushdown: spaghetti avoidance wrapper */
4807static int os_scsi_tape_open(struct inode * inode, struct file * filp)
4808{
4809	int ret;
4810
4811	mutex_lock(&osst_int_mutex);
4812	ret = __os_scsi_tape_open(inode, filp);
4813	mutex_unlock(&osst_int_mutex);
4814	return ret;
4815}
4816
4817
4818
4819/* Flush the tape buffer before close */
4820static int os_scsi_tape_flush(struct file * filp, fl_owner_t id)
4821{
4822	int		      result = 0, result2;
4823	struct osst_tape    * STp    = filp->private_data;
4824	struct st_modedef   * STm    = &(STp->modes[STp->current_mode]);
4825	struct st_partstat  * STps   = &(STp->ps[STp->partition]);
4826	struct osst_request * SRpnt  = NULL;
4827	char		    * name   = tape_name(STp);
4828
4829	if (file_count(filp) > 1)
4830		return 0;
4831
4832	if ((STps->rw == ST_WRITING || STp->dirty) && !STp->pos_unknown) {
4833		STp->write_type = OS_WRITE_DATA;
4834		result = osst_flush_write_buffer(STp, &SRpnt);
4835		if (result != 0 && result != (-ENOSPC))
4836			goto out;
4837	}
4838	if ( STps->rw >= ST_WRITING && !STp->pos_unknown) {
4839
4840#if DEBUG
4841		if (debugging) {
4842			printk(OSST_DEB_MSG "%s:D: File length %ld bytes.\n",
4843					       name, (long)(filp->f_pos));
4844			printk(OSST_DEB_MSG "%s:D: Async write waits %d, finished %d.\n",
4845					       name, STp->nbr_waits, STp->nbr_finished);
4846		}
4847#endif
4848		result = osst_write_trailer(STp, &SRpnt, !(STp->rew_at_close));
4849#if DEBUG
4850		if (debugging)
4851			printk(OSST_DEB_MSG "%s:D: Buffer flushed, %d EOF(s) written\n",
4852					       name, 1+STp->two_fm);
4853#endif
4854	}
4855	else if (!STp->rew_at_close) {
4856		STps = &(STp->ps[STp->partition]);
4857		if (!STm->sysv || STps->rw != ST_READING) {
4858			if (STp->can_bsr)
4859				result = osst_flush_buffer(STp, &SRpnt, 0); /* this is the default path */
4860			else if (STps->eof == ST_FM_HIT) {
4861				result = cross_eof(STp, &SRpnt, 0);
4862					if (result) {
4863						if (STps->drv_file >= 0)
4864							STps->drv_file++;
4865						STps->drv_block = 0;
4866						STps->eof = ST_FM;
4867					}
4868					else
4869						STps->eof = ST_NOEOF;
4870			}
4871		}
4872		else if ((STps->eof == ST_NOEOF &&
4873			  !(result = cross_eof(STp, &SRpnt, 1))) ||
4874			 STps->eof == ST_FM_HIT) {
4875			if (STps->drv_file >= 0)
4876				STps->drv_file++;
4877			STps->drv_block = 0;
4878			STps->eof = ST_FM;
4879		}
4880	}
4881
4882out:
4883	if (STp->rew_at_close) {
4884		result2 = osst_position_tape_and_confirm(STp, &SRpnt, STp->first_data_ppos);
4885		STps->drv_file = STps->drv_block = STp->frame_seq_number = STp->logical_blk_num = 0;
4886		if (result == 0 && result2 < 0)
4887			result = result2;
4888	}
4889	if (SRpnt) osst_release_request(SRpnt);
4890
4891	if (STp->abort_count || STp->recover_count) {
4892		printk(KERN_INFO "%s:I:", name);
4893		if (STp->abort_count)
4894			printk(" %d unrecovered errors", STp->abort_count);
4895		if (STp->recover_count)
4896			printk(" %d recovered errors", STp->recover_count);
4897		if (STp->write_count)
4898			printk(" in %d frames written", STp->write_count);
4899		if (STp->read_count)
4900			printk(" in %d frames read", STp->read_count);
4901		printk("\n");
4902		STp->recover_count = 0;
4903		STp->abort_count   = 0;
4904	}
4905	STp->write_count = 0;
4906	STp->read_count  = 0;
4907
4908	return result;
4909}
4910
4911
4912/* Close the device and release it */
4913static int os_scsi_tape_close(struct inode * inode, struct file * filp)
4914{
4915	int		      result = 0;
4916	struct osst_tape    * STp    = filp->private_data;
4917
4918	if (STp->door_locked == ST_LOCKED_AUTO)
4919		do_door_lock(STp, 0);
4920
4921	if (STp->raw)
4922		STp->header_ok = 0;
4923
4924	normalize_buffer(STp->buffer);
4925	write_lock(&os_scsi_tapes_lock);
4926	STp->in_use = 0;
4927	write_unlock(&os_scsi_tapes_lock);
4928
4929	scsi_device_put(STp->device);
4930
4931	return result;
4932}
4933
4934
4935/* The ioctl command */
4936static long osst_ioctl(struct file * file,
4937	 unsigned int cmd_in, unsigned long arg)
4938{
4939	int		      i, cmd_nr, cmd_type, blk, retval = 0;
4940	struct st_modedef   * STm;
4941	struct st_partstat  * STps;
4942	struct osst_request * SRpnt = NULL;
4943	struct osst_tape    * STp   = file->private_data;
4944	char		    * name  = tape_name(STp);
4945	void	    __user  * p     = (void __user *)arg;
4946
4947	mutex_lock(&osst_int_mutex);
4948	if (mutex_lock_interruptible(&STp->lock)) {
4949		mutex_unlock(&osst_int_mutex);
4950		return -ERESTARTSYS;
4951	}
4952
4953#if DEBUG
4954	if (debugging && !STp->in_use) {
4955		printk(OSST_DEB_MSG "%s:D: Incorrect device.\n", name);
4956		retval = (-EIO);
4957		goto out;
4958	}
4959#endif
4960	STm = &(STp->modes[STp->current_mode]);
4961	STps = &(STp->ps[STp->partition]);
4962
4963	/*
4964	 * If we are in the middle of error recovery, don't let anyone
4965	 * else try and use this device.  Also, if error recovery fails, it
4966	 * may try and take the device offline, in which case all further
4967	 * access to the device is prohibited.
4968	 */
4969	if( !scsi_block_when_processing_errors(STp->device) ) {
4970		retval = (-ENXIO);
4971		goto out;
4972	}
4973
4974	cmd_type = _IOC_TYPE(cmd_in);
4975	cmd_nr   = _IOC_NR(cmd_in);
4976#if DEBUG
4977	printk(OSST_DEB_MSG "%s:D: Ioctl %d,%d in %s mode\n", name,
4978			    cmd_type, cmd_nr, STp->raw?"raw":"normal");
4979#endif
4980	if (cmd_type == _IOC_TYPE(MTIOCTOP) && cmd_nr == _IOC_NR(MTIOCTOP)) {
4981		struct mtop mtc;
4982		int    auto_weof = 0;
4983
4984		if (_IOC_SIZE(cmd_in) != sizeof(mtc)) {
4985			retval = (-EINVAL);
4986			goto out;
4987		}
4988
4989		i = copy_from_user((char *) &mtc, p, sizeof(struct mtop));
4990		if (i) {
4991			retval = (-EFAULT);
4992			goto out;
4993		}
4994
4995		if (mtc.mt_op == MTSETDRVBUFFER && !capable(CAP_SYS_ADMIN)) {
4996			printk(KERN_WARNING "%s:W: MTSETDRVBUFFER only allowed for root.\n", name);
4997			retval = (-EPERM);
4998			goto out;
4999		}
5000
5001		if (!STm->defined && (mtc.mt_op != MTSETDRVBUFFER && (mtc.mt_count & MT_ST_OPTIONS) == 0)) {
5002			retval = (-ENXIO);
5003			goto out;
5004		}
5005
5006		if (!STp->pos_unknown) {
5007
5008			if (STps->eof == ST_FM_HIT) {
5009				if (mtc.mt_op == MTFSF || mtc.mt_op == MTFSFM|| mtc.mt_op == MTEOM) {
5010					mtc.mt_count -= 1;
5011					if (STps->drv_file >= 0)
5012						STps->drv_file += 1;
5013				}
5014				else if (mtc.mt_op == MTBSF || mtc.mt_op == MTBSFM) {
5015					mtc.mt_count += 1;
5016					if (STps->drv_file >= 0)
5017						STps->drv_file += 1;
5018				}
5019			}
5020
5021			if (mtc.mt_op == MTSEEK) {
5022				/* Old position must be restored if partition will be changed */
5023				i = !STp->can_partitions || (STp->new_partition != STp->partition);
5024			}
5025			else {
5026				i = mtc.mt_op == MTREW   || mtc.mt_op == MTOFFL ||
5027				    mtc.mt_op == MTRETEN || mtc.mt_op == MTEOM  ||
5028				    mtc.mt_op == MTLOCK  || mtc.mt_op == MTLOAD ||
5029				    mtc.mt_op == MTFSF   || mtc.mt_op == MTFSFM ||
5030				    mtc.mt_op == MTBSF   || mtc.mt_op == MTBSFM ||
5031				    mtc.mt_op == MTCOMPRESSION;
5032			}
5033			i = osst_flush_buffer(STp, &SRpnt, i);
5034			if (i < 0) {
5035				retval = i;
5036				goto out;
5037			}
5038		}
5039		else {
5040			/*
5041			 * If there was a bus reset, block further access
5042			 * to this device.  If the user wants to rewind the tape,
5043			 * then reset the flag and allow access again.
5044			 */
5045			if(mtc.mt_op != MTREW   &&
5046			   mtc.mt_op != MTOFFL  &&
5047			   mtc.mt_op != MTRETEN &&
5048			   mtc.mt_op != MTERASE &&
5049			   mtc.mt_op != MTSEEK  &&
5050			   mtc.mt_op != MTEOM)   {
5051				retval = (-EIO);
5052				goto out;
5053			}
5054			reset_state(STp);
5055			/* remove this when the midlevel properly clears was_reset */
5056			STp->device->was_reset = 0;
5057		}
5058
5059		if (mtc.mt_op != MTCOMPRESSION  && mtc.mt_op != MTLOCK         &&
5060		    mtc.mt_op != MTNOP          && mtc.mt_op != MTSETBLK       &&
5061		    mtc.mt_op != MTSETDENSITY   && mtc.mt_op != MTSETDRVBUFFER &&
5062		    mtc.mt_op != MTMKPART       && mtc.mt_op != MTSETPART      &&
5063		    mtc.mt_op != MTWEOF         && mtc.mt_op != MTWSM           ) {
5064
5065			/*
5066			 * The user tells us to move to another position on the tape.
5067			 * If we were appending to the tape content, that would leave
5068			 * the tape without proper end, in that case write EOD and
5069			 * update the header to reflect its position.
5070			 */
5071#if DEBUG
5072			printk(KERN_WARNING "%s:D: auto_weod %s at ffp=%d,efp=%d,fsn=%d,lbn=%d,fn=%d,bn=%d\n", name,
5073					STps->rw >= ST_WRITING ? "write" : STps->rw == ST_READING ? "read" : "idle",
5074					STp->first_frame_position, STp->eod_frame_ppos, STp->frame_seq_number,
5075					STp->logical_blk_num, STps->drv_file, STps->drv_block );
5076#endif
5077			if (STps->rw >= ST_WRITING && STp->first_frame_position >= STp->eod_frame_ppos) {
5078				auto_weof = ((STp->write_type != OS_WRITE_NEW_MARK) &&
5079							!(mtc.mt_op == MTREW || mtc.mt_op == MTOFFL));
5080				i = osst_write_trailer(STp, &SRpnt,
5081							!(mtc.mt_op == MTREW || mtc.mt_op == MTOFFL));
5082#if DEBUG
5083				printk(KERN_WARNING "%s:D: post trailer xeof=%d,ffp=%d,efp=%d,fsn=%d,lbn=%d,fn=%d,bn=%d\n",
5084						name, auto_weof, STp->first_frame_position, STp->eod_frame_ppos,
5085						STp->frame_seq_number, STp->logical_blk_num, STps->drv_file, STps->drv_block );
5086#endif
5087				if (i < 0) {
5088					retval = i;
5089					goto out;
5090				}
5091			}
5092			STps->rw = ST_IDLE;
5093		}
5094
5095		if (mtc.mt_op == MTOFFL && STp->door_locked != ST_UNLOCKED)
5096			do_door_lock(STp, 0);  /* Ignore result! */
5097
5098		if (mtc.mt_op == MTSETDRVBUFFER &&
5099		   (mtc.mt_count & MT_ST_OPTIONS) != 0) {
5100			retval = osst_set_options(STp, mtc.mt_count);
5101			goto out;
5102		}
5103
5104		if (mtc.mt_op == MTSETPART) {
5105			if (mtc.mt_count >= STp->nbr_partitions)
5106				retval = -EINVAL;
5107			else {
5108				STp->new_partition = mtc.mt_count;
5109				retval = 0;
5110			}
5111			goto out;
5112		}
5113
5114		if (mtc.mt_op == MTMKPART) {
5115			if (!STp->can_partitions) {
5116				retval = (-EINVAL);
5117				goto out;
5118			}
5119			if ((i = osst_int_ioctl(STp, &SRpnt, MTREW, 0)) < 0 /*||
5120			    (i = partition_tape(inode, mtc.mt_count)) < 0*/) {
5121				retval = i;
5122				goto out;
5123			}
5124			for (i=0; i < ST_NBR_PARTITIONS; i++) {
5125				STp->ps[i].rw = ST_IDLE;
5126				STp->ps[i].at_sm = 0;
5127				STp->ps[i].last_block_valid = 0;
5128			}
5129			STp->partition = STp->new_partition = 0;
5130			STp->nbr_partitions = 1;  /* Bad guess ?-) */
5131			STps->drv_block = STps->drv_file = 0;
5132			retval = 0;
5133			goto out;
5134	 	}
5135
5136		if (mtc.mt_op == MTSEEK) {
5137			if (STp->raw)
5138				i = osst_set_frame_position(STp, &SRpnt, mtc.mt_count, 0);
5139			else
5140				i = osst_seek_sector(STp, &SRpnt, mtc.mt_count);
5141			if (!STp->can_partitions)
5142				STp->ps[0].rw = ST_IDLE;
5143			retval = i;
5144			goto out;
5145		}
5146
5147		if (mtc.mt_op == MTLOCK || mtc.mt_op == MTUNLOCK) {
5148			retval = do_door_lock(STp, (mtc.mt_op == MTLOCK));
5149			goto out;
5150		}
5151
5152		if (auto_weof)
5153			cross_eof(STp, &SRpnt, 0);
5154
5155		if (mtc.mt_op == MTCOMPRESSION)
5156			retval = -EINVAL;       /* OnStream drives don't have compression hardware */
5157		else
5158			/* MTBSF MTBSFM MTBSR MTBSS MTEOM MTERASE MTFSF MTFSFB MTFSR MTFSS
5159			 * MTLOAD MTOFFL MTRESET MTRETEN MTREW MTUNLOAD MTWEOF MTWSM */
5160			retval = osst_int_ioctl(STp, &SRpnt, mtc.mt_op, mtc.mt_count);
5161		goto out;
5162	}
5163
5164	if (!STm->defined) {
5165		retval = (-ENXIO);
5166		goto out;
5167	}
5168
5169	if ((i = osst_flush_buffer(STp, &SRpnt, 0)) < 0) {
5170		retval = i;
5171		goto out;
5172	}
5173
5174	if (cmd_type == _IOC_TYPE(MTIOCGET) && cmd_nr == _IOC_NR(MTIOCGET)) {
5175		struct mtget mt_status;
5176
5177		if (_IOC_SIZE(cmd_in) != sizeof(struct mtget)) {
5178			 retval = (-EINVAL);
5179			 goto out;
5180		}
5181
5182		mt_status.mt_type = MT_ISONSTREAM_SC;
5183		mt_status.mt_erreg = STp->recover_erreg << MT_ST_SOFTERR_SHIFT;
5184		mt_status.mt_dsreg =
5185			((STp->block_size << MT_ST_BLKSIZE_SHIFT) & MT_ST_BLKSIZE_MASK) |
5186			((STp->density    << MT_ST_DENSITY_SHIFT) & MT_ST_DENSITY_MASK);
5187		mt_status.mt_blkno = STps->drv_block;
5188		mt_status.mt_fileno = STps->drv_file;
5189		if (STp->block_size != 0) {
5190			if (STps->rw == ST_WRITING)
5191				mt_status.mt_blkno += (STp->buffer)->buffer_bytes / STp->block_size;
5192			else if (STps->rw == ST_READING)
5193				mt_status.mt_blkno -= ((STp->buffer)->buffer_bytes +
5194							STp->block_size - 1) / STp->block_size;
5195		}
5196
5197		mt_status.mt_gstat = 0;
5198		if (STp->drv_write_prot)
5199			mt_status.mt_gstat |= GMT_WR_PROT(0xffffffff);
5200		if (mt_status.mt_blkno == 0) {
5201			if (mt_status.mt_fileno == 0)
5202				mt_status.mt_gstat |= GMT_BOT(0xffffffff);
5203			else
5204				mt_status.mt_gstat |= GMT_EOF(0xffffffff);
5205		}
5206		mt_status.mt_resid = STp->partition;
5207		if (STps->eof == ST_EOM_OK || STps->eof == ST_EOM_ERROR)
5208			mt_status.mt_gstat |= GMT_EOT(0xffffffff);
5209		else if (STps->eof >= ST_EOM_OK)
5210			mt_status.mt_gstat |= GMT_EOD(0xffffffff);
5211		if (STp->density == 1)
5212			mt_status.mt_gstat |= GMT_D_800(0xffffffff);
5213		else if (STp->density == 2)
5214			mt_status.mt_gstat |= GMT_D_1600(0xffffffff);
5215		else if (STp->density == 3)
5216			mt_status.mt_gstat |= GMT_D_6250(0xffffffff);
5217		if (STp->ready == ST_READY)
5218			mt_status.mt_gstat |= GMT_ONLINE(0xffffffff);
5219		if (STp->ready == ST_NO_TAPE)
5220			mt_status.mt_gstat |= GMT_DR_OPEN(0xffffffff);
5221		if (STps->at_sm)
5222			mt_status.mt_gstat |= GMT_SM(0xffffffff);
5223		if (STm->do_async_writes || (STm->do_buffer_writes && STp->block_size != 0) ||
5224		    STp->drv_buffer != 0)
5225			mt_status.mt_gstat |= GMT_IM_REP_EN(0xffffffff);
5226
5227		i = copy_to_user(p, &mt_status, sizeof(struct mtget));
5228		if (i) {
5229			retval = (-EFAULT);
5230			goto out;
5231		}
5232
5233		STp->recover_erreg = 0;  /* Clear after read */
5234		retval = 0;
5235		goto out;
5236	} /* End of MTIOCGET */
5237
5238	if (cmd_type == _IOC_TYPE(MTIOCPOS) && cmd_nr == _IOC_NR(MTIOCPOS)) {
5239		struct mtpos mt_pos;
5240
5241		if (_IOC_SIZE(cmd_in) != sizeof(struct mtpos)) {
5242			retval = (-EINVAL);
5243			goto out;
5244		}
5245		if (STp->raw)
5246			blk = osst_get_frame_position(STp, &SRpnt);
5247		else
5248			blk = osst_get_sector(STp, &SRpnt);
5249		if (blk < 0) {
5250			retval = blk;
5251			goto out;
5252		}
5253		mt_pos.mt_blkno = blk;
5254		i = copy_to_user(p, &mt_pos, sizeof(struct mtpos));
5255		if (i)
5256			retval = -EFAULT;
5257		goto out;
5258	}
5259	if (SRpnt) osst_release_request(SRpnt);
5260
5261	mutex_unlock(&STp->lock);
5262
5263	retval = scsi_ioctl(STp->device, cmd_in, p);
5264	mutex_unlock(&osst_int_mutex);
5265	return retval;
5266
5267out:
5268	if (SRpnt) osst_release_request(SRpnt);
5269
5270	mutex_unlock(&STp->lock);
5271	mutex_unlock(&osst_int_mutex);
5272
5273	return retval;
5274}
5275
5276#ifdef CONFIG_COMPAT
5277static long osst_compat_ioctl(struct file * file, unsigned int cmd_in, unsigned long arg)
5278{
5279	struct osst_tape *STp = file->private_data;
5280	struct scsi_device *sdev = STp->device;
5281	int ret = -ENOIOCTLCMD;
5282	if (sdev->host->hostt->compat_ioctl) {
5283
5284		ret = sdev->host->hostt->compat_ioctl(sdev, cmd_in, (void __user *)arg);
5285
5286	}
5287	return ret;
5288}
5289#endif
5290
5291
5292
5293/* Memory handling routines */
5294
5295/* Try to allocate a new tape buffer skeleton. Caller must not hold os_scsi_tapes_lock */
5296static struct osst_buffer * new_tape_buffer( int from_initialization, int need_dma, int max_sg )
5297{
5298	int i;
5299	gfp_t priority;
5300	struct osst_buffer *tb;
5301
5302	if (from_initialization)
5303		priority = GFP_ATOMIC;
5304	else
5305		priority = GFP_KERNEL;
5306
5307	i = sizeof(struct osst_buffer) + (osst_max_sg_segs - 1) * sizeof(struct scatterlist);
5308	tb = kzalloc(i, priority);
5309	if (!tb) {
5310		printk(KERN_NOTICE "osst :I: Can't allocate new tape buffer.\n");
5311		return NULL;
5312	}
5313
5314	tb->sg_segs = tb->orig_sg_segs = 0;
5315	tb->use_sg = max_sg;
5316	tb->in_use = 1;
5317	tb->dma = need_dma;
5318	tb->buffer_size = 0;
5319#if DEBUG
5320	if (debugging)
5321		printk(OSST_DEB_MSG
5322			"osst :D: Allocated tape buffer skeleton (%d bytes, %d segments, dma: %d).\n",
5323			   i, max_sg, need_dma);
5324#endif
5325	return tb;
5326}
5327
5328/* Try to allocate a temporary (while a user has the device open) enlarged tape buffer */
5329static int enlarge_buffer(struct osst_buffer *STbuffer, int need_dma)
5330{
5331	int segs, nbr, max_segs, b_size, order, got;
5332	gfp_t priority;
5333
5334	if (STbuffer->buffer_size >= OS_FRAME_SIZE)
5335		return 1;
5336
5337	if (STbuffer->sg_segs) {
5338		printk(KERN_WARNING "osst :A: Buffer not previously normalized.\n");
5339		normalize_buffer(STbuffer);
5340	}
5341	/* See how many segments we can use -- need at least two */
5342	nbr = max_segs = STbuffer->use_sg;
5343	if (nbr <= 2)
5344		return 0;
5345
5346	priority = GFP_KERNEL /* | __GFP_NOWARN */;
5347	if (need_dma)
5348		priority |= GFP_DMA;
5349
5350	/* Try to allocate the first segment up to OS_DATA_SIZE and the others
5351	   big enough to reach the goal (code assumes no segments in place) */
5352	for (b_size = OS_DATA_SIZE, order = OSST_FIRST_ORDER; b_size >= PAGE_SIZE; order--, b_size /= 2) {
5353		struct page *page = alloc_pages(priority, order);
5354
5355		STbuffer->sg[0].offset = 0;
5356		if (page != NULL) {
5357		    sg_set_page(&STbuffer->sg[0], page, b_size, 0);
5358		    STbuffer->b_data = page_address(page);
5359		    break;
5360		}
5361	}
5362	if (sg_page(&STbuffer->sg[0]) == NULL) {
5363		printk(KERN_NOTICE "osst :I: Can't allocate tape buffer main segment.\n");
5364		return 0;
5365	}
5366	/* Got initial segment of 'bsize,order', continue with same size if possible, except for AUX */
5367	for (segs=STbuffer->sg_segs=1, got=b_size;
5368	     segs < max_segs && got < OS_FRAME_SIZE; ) {
5369		struct page *page = alloc_pages(priority, (OS_FRAME_SIZE - got <= PAGE_SIZE) ? 0 : order);
5370		STbuffer->sg[segs].offset = 0;
5371		if (page == NULL) {
5372			printk(KERN_WARNING "osst :W: Failed to enlarge buffer to %d bytes.\n",
5373						OS_FRAME_SIZE);
5374#if DEBUG
5375			STbuffer->buffer_size = got;
5376#endif
5377			normalize_buffer(STbuffer);
5378			return 0;
5379		}
5380		sg_set_page(&STbuffer->sg[segs], page, (OS_FRAME_SIZE - got <= PAGE_SIZE / 2) ? (OS_FRAME_SIZE - got) : b_size, 0);
5381		got += STbuffer->sg[segs].length;
5382		STbuffer->buffer_size = got;
5383		STbuffer->sg_segs = ++segs;
5384	}
5385#if DEBUG
5386	if (debugging) {
5387		printk(OSST_DEB_MSG
5388			   "osst :D: Expanded tape buffer (%d bytes, %d->%d segments, dma: %d, at: %p).\n",
5389			   got, STbuffer->orig_sg_segs, STbuffer->sg_segs, need_dma, STbuffer->b_data);
5390		printk(OSST_DEB_MSG
5391			   "osst :D: segment sizes: first %d at %p, last %d bytes at %p.\n",
5392			   STbuffer->sg[0].length, page_address(STbuffer->sg[0].page),
5393			   STbuffer->sg[segs-1].length, page_address(STbuffer->sg[segs-1].page));
5394	}
5395#endif
5396
5397	return 1;
5398}
5399
5400
5401/* Release the segments */
5402static void normalize_buffer(struct osst_buffer *STbuffer)
5403{
5404  int i, order, b_size;
5405
5406	for (i=0; i < STbuffer->sg_segs; i++) {
5407
5408		for (b_size = PAGE_SIZE, order = 0;
5409		     b_size < STbuffer->sg[i].length;
5410		     b_size *= 2, order++);
5411
5412		__free_pages(sg_page(&STbuffer->sg[i]), order);
5413		STbuffer->buffer_size -= STbuffer->sg[i].length;
5414	}
5415#if DEBUG
5416	if (debugging && STbuffer->orig_sg_segs < STbuffer->sg_segs)
5417		printk(OSST_DEB_MSG "osst :D: Buffer at %p normalized to %d bytes (segs %d).\n",
5418			     STbuffer->b_data, STbuffer->buffer_size, STbuffer->sg_segs);
5419#endif
5420	STbuffer->sg_segs = STbuffer->orig_sg_segs = 0;
5421}
5422
5423
5424/* Move data from the user buffer to the tape buffer. Returns zero (success) or
5425   negative error code. */
5426static int append_to_buffer(const char __user *ubp, struct osst_buffer *st_bp, int do_count)
5427{
5428	int i, cnt, res, offset;
5429
5430	for (i=0, offset=st_bp->buffer_bytes;
5431	     i < st_bp->sg_segs && offset >= st_bp->sg[i].length; i++)
5432	offset -= st_bp->sg[i].length;
5433	if (i == st_bp->sg_segs) {  /* Should never happen */
5434		printk(KERN_WARNING "osst :A: Append_to_buffer offset overflow.\n");
5435		return (-EIO);
5436	}
5437	for ( ; i < st_bp->sg_segs && do_count > 0; i++) {
5438		cnt = st_bp->sg[i].length - offset < do_count ?
5439		      st_bp->sg[i].length - offset : do_count;
5440		res = copy_from_user(page_address(sg_page(&st_bp->sg[i])) + offset, ubp, cnt);
5441		if (res)
5442			return (-EFAULT);
5443		do_count -= cnt;
5444		st_bp->buffer_bytes += cnt;
5445		ubp += cnt;
5446		offset = 0;
5447	}
5448	if (do_count) {  /* Should never happen */
5449		printk(KERN_WARNING "osst :A: Append_to_buffer overflow (left %d).\n",
5450		       do_count);
5451		return (-EIO);
5452	}
5453	return 0;
5454}
5455
5456
5457/* Move data from the tape buffer to the user buffer. Returns zero (success) or
5458   negative error code. */
5459static int from_buffer(struct osst_buffer *st_bp, char __user *ubp, int do_count)
5460{
5461	int i, cnt, res, offset;
5462
5463	for (i=0, offset=st_bp->read_pointer;
5464	     i < st_bp->sg_segs && offset >= st_bp->sg[i].length; i++)
5465		offset -= st_bp->sg[i].length;
5466	if (i == st_bp->sg_segs) {  /* Should never happen */
5467		printk(KERN_WARNING "osst :A: From_buffer offset overflow.\n");
5468		return (-EIO);
5469	}
5470	for ( ; i < st_bp->sg_segs && do_count > 0; i++) {
5471		cnt = st_bp->sg[i].length - offset < do_count ?
5472		      st_bp->sg[i].length - offset : do_count;
5473		res = copy_to_user(ubp, page_address(sg_page(&st_bp->sg[i])) + offset, cnt);
5474		if (res)
5475			return (-EFAULT);
5476		do_count -= cnt;
5477		st_bp->buffer_bytes -= cnt;
5478		st_bp->read_pointer += cnt;
5479		ubp += cnt;
5480		offset = 0;
5481	}
5482	if (do_count) {  /* Should never happen */
5483		printk(KERN_WARNING "osst :A: From_buffer overflow (left %d).\n", do_count);
5484		return (-EIO);
5485	}
5486	return 0;
5487}
5488
5489/* Sets the tail of the buffer after fill point to zero.
5490   Returns zero (success) or negative error code.        */
5491static int osst_zero_buffer_tail(struct osst_buffer *st_bp)
5492{
5493	int	i, offset, do_count, cnt;
5494
5495	for (i = 0, offset = st_bp->buffer_bytes;
5496	     i < st_bp->sg_segs && offset >= st_bp->sg[i].length; i++)
5497		offset -= st_bp->sg[i].length;
5498	if (i == st_bp->sg_segs) {  /* Should never happen */
5499		printk(KERN_WARNING "osst :A: Zero_buffer offset overflow.\n");
5500		return (-EIO);
5501	}
5502	for (do_count = OS_DATA_SIZE - st_bp->buffer_bytes;
5503	     i < st_bp->sg_segs && do_count > 0; i++) {
5504		cnt = st_bp->sg[i].length - offset < do_count ?
5505		      st_bp->sg[i].length - offset : do_count ;
5506		memset(page_address(sg_page(&st_bp->sg[i])) + offset, 0, cnt);
5507		do_count -= cnt;
5508		offset = 0;
5509	}
5510	if (do_count) {  /* Should never happen */
5511		printk(KERN_WARNING "osst :A: Zero_buffer overflow (left %d).\n", do_count);
5512		return (-EIO);
5513	}
5514	return 0;
5515}
5516
5517/* Copy a osst 32K chunk of memory into the buffer.
5518   Returns zero (success) or negative error code.  */
5519static int osst_copy_to_buffer(struct osst_buffer *st_bp, unsigned char *ptr)
5520{
5521	int	i, cnt, do_count = OS_DATA_SIZE;
5522
5523	for (i = 0; i < st_bp->sg_segs && do_count > 0; i++) {
5524		cnt = st_bp->sg[i].length < do_count ?
5525		      st_bp->sg[i].length : do_count ;
5526		memcpy(page_address(sg_page(&st_bp->sg[i])), ptr, cnt);
5527		do_count -= cnt;
5528		ptr      += cnt;
5529	}
5530	if (do_count || i != st_bp->sg_segs-1) {  /* Should never happen */
5531		printk(KERN_WARNING "osst :A: Copy_to_buffer overflow (left %d at sg %d).\n",
5532					 do_count, i);
5533		return (-EIO);
5534	}
5535	return 0;
5536}
5537
5538/* Copy a osst 32K chunk of memory from the buffer.
5539   Returns zero (success) or negative error code.  */
5540static int osst_copy_from_buffer(struct osst_buffer *st_bp, unsigned char *ptr)
5541{
5542	int	i, cnt, do_count = OS_DATA_SIZE;
5543
5544	for (i = 0; i < st_bp->sg_segs && do_count > 0; i++) {
5545		cnt = st_bp->sg[i].length < do_count ?
5546		      st_bp->sg[i].length : do_count ;
5547		memcpy(ptr, page_address(sg_page(&st_bp->sg[i])), cnt);
5548		do_count -= cnt;
5549		ptr      += cnt;
5550	}
5551	if (do_count || i != st_bp->sg_segs-1) {  /* Should never happen */
5552		printk(KERN_WARNING "osst :A: Copy_from_buffer overflow (left %d at sg %d).\n",
5553					 do_count, i);
5554		return (-EIO);
5555	}
5556	return 0;
5557}
5558
5559
5560/* Module housekeeping */
5561
5562static void validate_options (void)
5563{
5564  if (max_dev > 0)
5565		osst_max_dev = max_dev;
5566  if (write_threshold_kbs > 0)
5567		osst_write_threshold = write_threshold_kbs * ST_KILOBYTE;
5568  if (osst_write_threshold > osst_buffer_size)
5569		osst_write_threshold = osst_buffer_size;
5570  if (max_sg_segs >= OSST_FIRST_SG)
5571		osst_max_sg_segs = max_sg_segs;
5572#if DEBUG
5573  printk(OSST_DEB_MSG "osst :D: max tapes %d, write threshold %d, max s/g segs %d.\n",
5574			   osst_max_dev, osst_write_threshold, osst_max_sg_segs);
5575#endif
5576}
5577
5578#ifndef MODULE
5579/* Set the boot options. Syntax: osst=xxx,yyy,...
5580   where xxx is write threshold in 1024 byte blocks,
5581   and   yyy is number of s/g segments to use. */
5582static int __init osst_setup (char *str)
5583{
5584  int i, ints[5];
5585  char *stp;
5586
5587  stp = get_options(str, ARRAY_SIZE(ints), ints);
5588
5589  if (ints[0] > 0) {
5590	for (i = 0; i < ints[0] && i < ARRAY_SIZE(parms); i++)
5591		  *parms[i].val = ints[i + 1];
5592  } else {
5593	while (stp != NULL) {
5594		for (i = 0; i < ARRAY_SIZE(parms); i++) {
5595			int len = strlen(parms[i].name);
5596			if (!strncmp(stp, parms[i].name, len) &&
5597			    (*(stp + len) == ':' || *(stp + len) == '=')) {
5598				*parms[i].val =
5599					simple_strtoul(stp + len + 1, NULL, 0);
5600				break;
5601			}
5602		}
5603		if (i >= ARRAY_SIZE(parms))
5604			printk(KERN_INFO "osst :I: Illegal parameter in '%s'\n",
5605			       stp);
5606		stp = strchr(stp, ',');
5607		if (stp)
5608			stp++;
5609	}
5610  }
5611
5612  return 1;
5613}
5614
5615__setup("osst=", osst_setup);
5616
5617#endif
5618
5619static const struct file_operations osst_fops = {
5620	.owner =        THIS_MODULE,
5621	.read =         osst_read,
5622	.write =        osst_write,
5623	.unlocked_ioctl = osst_ioctl,
5624#ifdef CONFIG_COMPAT
5625	.compat_ioctl = osst_compat_ioctl,
5626#endif
5627	.open =         os_scsi_tape_open,
5628	.flush =        os_scsi_tape_flush,
5629	.release =      os_scsi_tape_close,
5630	.llseek =	noop_llseek,
5631};
5632
5633static int osst_supports(struct scsi_device * SDp)
5634{
5635	struct	osst_support_data {
5636		char *vendor;
5637		char *model;
5638		char *rev;
5639		char *driver_hint; /* Name of the correct driver, NULL if unknown */
5640	};
5641
5642static	struct	osst_support_data support_list[] = {
5643		/* {"XXX", "Yy-", "", NULL},  example */
5644		SIGS_FROM_OSST,
5645		{NULL, }};
5646
5647	struct	osst_support_data *rp;
5648
5649	/* We are willing to drive OnStream SC-x0 as well as the
5650	 * 	 * IDE, ParPort, FireWire, USB variants, if accessible by
5651	 * 	 	 * emulation layer (ide-scsi, usb-storage, ...) */
5652
5653	for (rp=&(support_list[0]); rp->vendor != NULL; rp++)
5654		if (!strncmp(rp->vendor, SDp->vendor, strlen(rp->vendor)) &&
5655		    !strncmp(rp->model, SDp->model, strlen(rp->model)) &&
5656		    !strncmp(rp->rev, SDp->rev, strlen(rp->rev)))
5657			return 1;
5658	return 0;
5659}
5660
5661/*
5662 * sysfs support for osst driver parameter information
5663 */
5664
5665static ssize_t osst_version_show(struct device_driver *ddd, char *buf)
5666{
5667	return snprintf(buf, PAGE_SIZE, "%s\n", osst_version);
5668}
5669
5670static DRIVER_ATTR(version, S_IRUGO, osst_version_show, NULL);
5671
5672static int osst_create_sysfs_files(struct device_driver *sysfs)
5673{
5674	return driver_create_file(sysfs, &driver_attr_version);
5675}
5676
5677static void osst_remove_sysfs_files(struct device_driver *sysfs)
5678{
5679	driver_remove_file(sysfs, &driver_attr_version);
5680}
5681
5682/*
5683 * sysfs support for accessing ADR header information
5684 */
5685
5686static ssize_t osst_adr_rev_show(struct device *dev,
5687				 struct device_attribute *attr, char *buf)
5688{
5689	struct osst_tape * STp = (struct osst_tape *) dev_get_drvdata (dev);
5690	ssize_t l = 0;
5691
5692	if (STp && STp->header_ok && STp->linux_media)
5693		l = snprintf(buf, PAGE_SIZE, "%d.%d\n", STp->header_cache->major_rev, STp->header_cache->minor_rev);
5694	return l;
5695}
5696
5697DEVICE_ATTR(ADR_rev, S_IRUGO, osst_adr_rev_show, NULL);
5698
5699static ssize_t osst_linux_media_version_show(struct device *dev,
5700					     struct device_attribute *attr,
5701					     char *buf)
5702{
5703	struct osst_tape * STp = (struct osst_tape *) dev_get_drvdata (dev);
5704	ssize_t l = 0;
5705
5706	if (STp && STp->header_ok && STp->linux_media)
5707		l = snprintf(buf, PAGE_SIZE, "LIN%d\n", STp->linux_media_version);
5708	return l;
5709}
5710
5711DEVICE_ATTR(media_version, S_IRUGO, osst_linux_media_version_show, NULL);
5712
5713static ssize_t osst_capacity_show(struct device *dev,
5714				  struct device_attribute *attr, char *buf)
5715{
5716	struct osst_tape * STp = (struct osst_tape *) dev_get_drvdata (dev);
5717	ssize_t l = 0;
5718
5719	if (STp && STp->header_ok && STp->linux_media)
5720		l = snprintf(buf, PAGE_SIZE, "%d\n", STp->capacity);
5721	return l;
5722}
5723
5724DEVICE_ATTR(capacity, S_IRUGO, osst_capacity_show, NULL);
5725
5726static ssize_t osst_first_data_ppos_show(struct device *dev,
5727					 struct device_attribute *attr,
5728					 char *buf)
5729{
5730	struct osst_tape * STp = (struct osst_tape *) dev_get_drvdata (dev);
5731	ssize_t l = 0;
5732
5733	if (STp && STp->header_ok && STp->linux_media)
5734		l = snprintf(buf, PAGE_SIZE, "%d\n", STp->first_data_ppos);
5735	return l;
5736}
5737
5738DEVICE_ATTR(BOT_frame, S_IRUGO, osst_first_data_ppos_show, NULL);
5739
5740static ssize_t osst_eod_frame_ppos_show(struct device *dev,
5741					struct device_attribute *attr,
5742					char *buf)
5743{
5744	struct osst_tape * STp = (struct osst_tape *) dev_get_drvdata (dev);
5745	ssize_t l = 0;
5746
5747	if (STp && STp->header_ok && STp->linux_media)
5748		l = snprintf(buf, PAGE_SIZE, "%d\n", STp->eod_frame_ppos);
5749	return l;
5750}
5751
5752DEVICE_ATTR(EOD_frame, S_IRUGO, osst_eod_frame_ppos_show, NULL);
5753
5754static ssize_t osst_filemark_cnt_show(struct device *dev,
5755				      struct device_attribute *attr, char *buf)
5756{
5757	struct osst_tape * STp = (struct osst_tape *) dev_get_drvdata (dev);
5758	ssize_t l = 0;
5759
5760	if (STp && STp->header_ok && STp->linux_media)
5761		l = snprintf(buf, PAGE_SIZE, "%d\n", STp->filemark_cnt);
5762	return l;
5763}
5764
5765DEVICE_ATTR(file_count, S_IRUGO, osst_filemark_cnt_show, NULL);
5766
5767static struct class *osst_sysfs_class;
5768
5769static int osst_sysfs_init(void)
5770{
5771	osst_sysfs_class = class_create(THIS_MODULE, "onstream_tape");
5772	if (IS_ERR(osst_sysfs_class)) {
5773		printk(KERN_ERR "osst :W: Unable to register sysfs class\n");
5774		return PTR_ERR(osst_sysfs_class);
5775	}
5776
5777	return 0;
5778}
5779
5780static void osst_sysfs_destroy(dev_t dev)
5781{
5782	device_destroy(osst_sysfs_class, dev);
5783}
5784
5785static int osst_sysfs_add(dev_t dev, struct device *device, struct osst_tape * STp, char * name)
5786{
5787	struct device *osst_member;
5788	int err;
5789
5790	osst_member = device_create(osst_sysfs_class, device, dev, STp,
5791				    "%s", name);
5792	if (IS_ERR(osst_member)) {
5793		printk(KERN_WARNING "osst :W: Unable to add sysfs class member %s\n", name);
5794		return PTR_ERR(osst_member);
5795	}
5796
5797	err = device_create_file(osst_member, &dev_attr_ADR_rev);
5798	if (err)
5799		goto err_out;
5800	err = device_create_file(osst_member, &dev_attr_media_version);
5801	if (err)
5802		goto err_out;
5803	err = device_create_file(osst_member, &dev_attr_capacity);
5804	if (err)
5805		goto err_out;
5806	err = device_create_file(osst_member, &dev_attr_BOT_frame);
5807	if (err)
5808		goto err_out;
5809	err = device_create_file(osst_member, &dev_attr_EOD_frame);
5810	if (err)
5811		goto err_out;
5812	err = device_create_file(osst_member, &dev_attr_file_count);
5813	if (err)
5814		goto err_out;
5815
5816	return 0;
5817
5818err_out:
5819	osst_sysfs_destroy(dev);
5820	return err;
5821}
5822
5823static void osst_sysfs_cleanup(void)
5824{
5825	class_destroy(osst_sysfs_class);
5826}
5827
5828/*
5829 * osst startup / cleanup code
5830 */
5831
5832static int osst_probe(struct device *dev)
5833{
5834	struct scsi_device * SDp = to_scsi_device(dev);
5835	struct osst_tape   * tpnt;
5836	struct st_modedef  * STm;
5837	struct st_partstat * STps;
5838	struct osst_buffer * buffer;
5839	struct gendisk	   * drive;
5840	int		     i, dev_num, err = -ENODEV;
5841
5842	if (SDp->type != TYPE_TAPE || !osst_supports(SDp))
5843		return -ENODEV;
5844
5845	drive = alloc_disk(1);
5846	if (!drive) {
5847		printk(KERN_ERR "osst :E: Out of memory. Device not attached.\n");
5848		return -ENODEV;
5849	}
5850
5851	/* if this is the first attach, build the infrastructure */
5852	write_lock(&os_scsi_tapes_lock);
5853	if (os_scsi_tapes == NULL) {
5854		os_scsi_tapes = kmalloc(osst_max_dev * sizeof(struct osst_tape *), GFP_ATOMIC);
5855		if (os_scsi_tapes == NULL) {
5856			write_unlock(&os_scsi_tapes_lock);
5857			printk(KERN_ERR "osst :E: Unable to allocate array for OnStream SCSI tapes.\n");
5858			goto out_put_disk;
5859		}
5860		for (i=0; i < osst_max_dev; ++i) os_scsi_tapes[i] = NULL;
5861	}
5862
5863	if (osst_nr_dev >= osst_max_dev) {
5864		write_unlock(&os_scsi_tapes_lock);
5865		printk(KERN_ERR "osst :E: Too many tape devices (max. %d).\n", osst_max_dev);
5866		goto out_put_disk;
5867	}
5868
5869	/* find a free minor number */
5870	for (i = 0; i < osst_max_dev && os_scsi_tapes[i]; i++)
5871		;
5872	if(i >= osst_max_dev) panic ("Scsi_devices corrupt (osst)");
5873	dev_num = i;
5874
5875	/* allocate a struct osst_tape for this device */
5876	tpnt = kzalloc(sizeof(struct osst_tape), GFP_ATOMIC);
5877	if (!tpnt) {
5878		write_unlock(&os_scsi_tapes_lock);
5879		printk(KERN_ERR "osst :E: Can't allocate device descriptor, device not attached.\n");
5880		goto out_put_disk;
5881	}
5882
5883	/* allocate a buffer for this device */
5884	i = SDp->host->sg_tablesize;
5885	if (osst_max_sg_segs < i)
5886		i = osst_max_sg_segs;
5887	buffer = new_tape_buffer(1, SDp->host->unchecked_isa_dma, i);
5888	if (buffer == NULL) {
5889		write_unlock(&os_scsi_tapes_lock);
5890		printk(KERN_ERR "osst :E: Unable to allocate a tape buffer, device not attached.\n");
5891		kfree(tpnt);
5892		goto out_put_disk;
5893	}
5894	os_scsi_tapes[dev_num] = tpnt;
5895	tpnt->buffer = buffer;
5896	tpnt->device = SDp;
5897	drive->private_data = &tpnt->driver;
5898	sprintf(drive->disk_name, "osst%d", dev_num);
5899	tpnt->driver = &osst_template;
5900	tpnt->drive = drive;
5901	tpnt->in_use = 0;
5902	tpnt->capacity = 0xfffff;
5903	tpnt->dirty = 0;
5904	tpnt->drv_buffer = 1;  /* Try buffering if no mode sense */
5905	tpnt->restr_dma = (SDp->host)->unchecked_isa_dma;
5906	tpnt->density = 0;
5907	tpnt->do_auto_lock = OSST_AUTO_LOCK;
5908	tpnt->can_bsr = OSST_IN_FILE_POS;
5909	tpnt->can_partitions = 0;
5910	tpnt->two_fm = OSST_TWO_FM;
5911	tpnt->fast_mteom = OSST_FAST_MTEOM;
5912	tpnt->scsi2_logical = OSST_SCSI2LOGICAL; /* FIXME */
5913	tpnt->write_threshold = osst_write_threshold;
5914	tpnt->default_drvbuffer = 0xff; /* No forced buffering */
5915	tpnt->partition = 0;
5916	tpnt->new_partition = 0;
5917	tpnt->nbr_partitions = 0;
5918	tpnt->min_block = 512;
5919	tpnt->max_block = OS_DATA_SIZE;
5920	tpnt->timeout = OSST_TIMEOUT;
5921	tpnt->long_timeout = OSST_LONG_TIMEOUT;
5922
5923	/* Recognize OnStream tapes */
5924	/* We don't need to test for OnStream, as this has been done in detect () */
5925	tpnt->os_fw_rev = osst_parse_firmware_rev (SDp->rev);
5926	tpnt->omit_blklims = 1;
5927
5928	tpnt->poll = (strncmp(SDp->model, "DI-", 3) == 0) ||
5929		     (strncmp(SDp->model, "FW-", 3) == 0) || OSST_FW_NEED_POLL(tpnt->os_fw_rev,SDp);
5930	tpnt->frame_in_buffer = 0;
5931	tpnt->header_ok = 0;
5932	tpnt->linux_media = 0;
5933	tpnt->header_cache = NULL;
5934
5935	for (i=0; i < ST_NBR_MODES; i++) {
5936		STm = &(tpnt->modes[i]);
5937		STm->defined = 0;
5938		STm->sysv = OSST_SYSV;
5939		STm->defaults_for_writes = 0;
5940		STm->do_async_writes = OSST_ASYNC_WRITES;
5941		STm->do_buffer_writes = OSST_BUFFER_WRITES;
5942		STm->do_read_ahead = OSST_READ_AHEAD;
5943		STm->default_compression = ST_DONT_TOUCH;
5944		STm->default_blksize = 512;
5945		STm->default_density = (-1);  /* No forced density */
5946	}
5947
5948	for (i=0; i < ST_NBR_PARTITIONS; i++) {
5949		STps = &(tpnt->ps[i]);
5950		STps->rw = ST_IDLE;
5951		STps->eof = ST_NOEOF;
5952		STps->at_sm = 0;
5953		STps->last_block_valid = 0;
5954		STps->drv_block = (-1);
5955		STps->drv_file = (-1);
5956	}
5957
5958	tpnt->current_mode = 0;
5959	tpnt->modes[0].defined = 1;
5960	tpnt->modes[2].defined = 1;
5961	tpnt->density_changed = tpnt->compression_changed = tpnt->blksize_changed = 0;
5962
5963	mutex_init(&tpnt->lock);
5964	osst_nr_dev++;
5965	write_unlock(&os_scsi_tapes_lock);
5966
5967	{
5968		char name[8];
5969
5970		/*  Rewind entry  */
5971		err = osst_sysfs_add(MKDEV(OSST_MAJOR, dev_num), dev, tpnt, tape_name(tpnt));
5972		if (err)
5973			goto out_free_buffer;
5974
5975		/*  No-rewind entry  */
5976		snprintf(name, 8, "%s%s", "n", tape_name(tpnt));
5977		err = osst_sysfs_add(MKDEV(OSST_MAJOR, dev_num + 128), dev, tpnt, name);
5978		if (err)
5979			goto out_free_sysfs1;
5980	}
5981
5982	sdev_printk(KERN_INFO, SDp,
5983		"osst :I: Attached OnStream %.5s tape as %s\n",
5984		SDp->model, tape_name(tpnt));
5985
5986	return 0;
5987
5988out_free_sysfs1:
5989	osst_sysfs_destroy(MKDEV(OSST_MAJOR, dev_num));
5990out_free_buffer:
5991	kfree(buffer);
5992out_put_disk:
5993        put_disk(drive);
5994        return err;
5995};
5996
5997static int osst_remove(struct device *dev)
5998{
5999	struct scsi_device * SDp = to_scsi_device(dev);
6000	struct osst_tape * tpnt;
6001	int i;
6002
6003	if ((SDp->type != TYPE_TAPE) || (osst_nr_dev <= 0))
6004		return 0;
6005
6006	write_lock(&os_scsi_tapes_lock);
6007	for(i=0; i < osst_max_dev; i++) {
6008		if((tpnt = os_scsi_tapes[i]) && (tpnt->device == SDp)) {
6009			osst_sysfs_destroy(MKDEV(OSST_MAJOR, i));
6010			osst_sysfs_destroy(MKDEV(OSST_MAJOR, i+128));
6011			tpnt->device = NULL;
6012			put_disk(tpnt->drive);
6013			os_scsi_tapes[i] = NULL;
6014			osst_nr_dev--;
6015			write_unlock(&os_scsi_tapes_lock);
6016			vfree(tpnt->header_cache);
6017			if (tpnt->buffer) {
6018				normalize_buffer(tpnt->buffer);
6019				kfree(tpnt->buffer);
6020			}
6021			kfree(tpnt);
6022			return 0;
6023		}
6024	}
6025	write_unlock(&os_scsi_tapes_lock);
6026	return 0;
6027}
6028
6029static int __init init_osst(void)
6030{
6031	int err;
6032
6033	printk(KERN_INFO "osst :I: Tape driver with OnStream support version %s\nosst :I: %s\n", osst_version, cvsid);
6034
6035	validate_options();
6036
6037	err = osst_sysfs_init();
6038	if (err)
6039		return err;
6040
6041	err = register_chrdev(OSST_MAJOR, "osst", &osst_fops);
6042	if (err < 0) {
6043		printk(KERN_ERR "osst :E: Unable to register major %d for OnStream tapes\n", OSST_MAJOR);
6044		goto err_out;
6045	}
6046
6047	err = scsi_register_driver(&osst_template.gendrv);
6048	if (err)
6049		goto err_out_chrdev;
6050
6051	err = osst_create_sysfs_files(&osst_template.gendrv);
6052	if (err)
6053		goto err_out_scsidrv;
6054
6055	return 0;
6056
6057err_out_scsidrv:
6058	scsi_unregister_driver(&osst_template.gendrv);
6059err_out_chrdev:
6060	unregister_chrdev(OSST_MAJOR, "osst");
6061err_out:
6062	osst_sysfs_cleanup();
6063	return err;
6064}
6065
6066static void __exit exit_osst (void)
6067{
6068	int i;
6069	struct osst_tape * STp;
6070
6071	osst_remove_sysfs_files(&osst_template.gendrv);
6072	scsi_unregister_driver(&osst_template.gendrv);
6073	unregister_chrdev(OSST_MAJOR, "osst");
6074	osst_sysfs_cleanup();
6075
6076	if (os_scsi_tapes) {
6077		for (i=0; i < osst_max_dev; ++i) {
6078			if (!(STp = os_scsi_tapes[i])) continue;
6079			/* This is defensive, supposed to happen during detach */
6080			vfree(STp->header_cache);
6081			if (STp->buffer) {
6082				normalize_buffer(STp->buffer);
6083				kfree(STp->buffer);
6084			}
6085			put_disk(STp->drive);
6086			kfree(STp);
6087		}
6088		kfree(os_scsi_tapes);
6089	}
6090	printk(KERN_INFO "osst :I: Unloaded.\n");
6091}
6092
6093module_init(init_osst);
6094module_exit(exit_osst);
6095