xref: /linux/drivers/scsi/ch.c (revision 3932b9ca55b0be314a36d3e84faff3e823c081f5)
1 /*
2  * SCSI Media Changer device driver for Linux 2.6
3  *
4  *     (c) 1996-2003 Gerd Knorr <kraxel@bytesex.org>
5  *
6  */
7 
8 #define VERSION "0.25"
9 
10 #include <linux/module.h>
11 #include <linux/init.h>
12 #include <linux/fs.h>
13 #include <linux/kernel.h>
14 #include <linux/mm.h>
15 #include <linux/major.h>
16 #include <linux/string.h>
17 #include <linux/errno.h>
18 #include <linux/interrupt.h>
19 #include <linux/blkdev.h>
20 #include <linux/completion.h>
21 #include <linux/compat.h>
22 #include <linux/chio.h>			/* here are all the ioctls */
23 #include <linux/mutex.h>
24 #include <linux/idr.h>
25 #include <linux/slab.h>
26 
27 #include <scsi/scsi.h>
28 #include <scsi/scsi_cmnd.h>
29 #include <scsi/scsi_driver.h>
30 #include <scsi/scsi_ioctl.h>
31 #include <scsi/scsi_host.h>
32 #include <scsi/scsi_device.h>
33 #include <scsi/scsi_eh.h>
34 #include <scsi/scsi_dbg.h>
35 
36 #define CH_DT_MAX       16
37 #define CH_TYPES        8
38 #define CH_MAX_DEVS     128
39 
40 MODULE_DESCRIPTION("device driver for scsi media changer devices");
41 MODULE_AUTHOR("Gerd Knorr <kraxel@bytesex.org>");
42 MODULE_LICENSE("GPL");
43 MODULE_ALIAS_CHARDEV_MAJOR(SCSI_CHANGER_MAJOR);
44 MODULE_ALIAS_SCSI_DEVICE(TYPE_MEDIUM_CHANGER);
45 
46 static DEFINE_MUTEX(ch_mutex);
47 static int init = 1;
48 module_param(init, int, 0444);
49 MODULE_PARM_DESC(init, \
50     "initialize element status on driver load (default: on)");
51 
52 static int timeout_move = 300;
53 module_param(timeout_move, int, 0644);
54 MODULE_PARM_DESC(timeout_move,"timeout for move commands "
55 		 "(default: 300 seconds)");
56 
57 static int timeout_init = 3600;
58 module_param(timeout_init, int, 0644);
59 MODULE_PARM_DESC(timeout_init,"timeout for INITIALIZE ELEMENT STATUS "
60 		 "(default: 3600 seconds)");
61 
62 static int verbose = 1;
63 module_param(verbose, int, 0644);
64 MODULE_PARM_DESC(verbose,"be verbose (default: on)");
65 
66 static int debug = 0;
67 module_param(debug, int, 0644);
68 MODULE_PARM_DESC(debug,"enable/disable debug messages, also prints more "
69 		 "detailed sense codes on scsi errors (default: off)");
70 
71 static int dt_id[CH_DT_MAX] = { [ 0 ... (CH_DT_MAX-1) ] = -1 };
72 static int dt_lun[CH_DT_MAX];
73 module_param_array(dt_id,  int, NULL, 0444);
74 module_param_array(dt_lun, int, NULL, 0444);
75 
76 /* tell the driver about vendor-specific slots */
77 static int vendor_firsts[CH_TYPES-4];
78 static int vendor_counts[CH_TYPES-4];
79 module_param_array(vendor_firsts, int, NULL, 0444);
80 module_param_array(vendor_counts, int, NULL, 0444);
81 
82 static const char * vendor_labels[CH_TYPES-4] = {
83 	"v0", "v1", "v2", "v3"
84 };
85 // module_param_string_array(vendor_labels, NULL, 0444);
86 
87 #define ch_printk(prefix, ch, fmt, a...) \
88 	sdev_printk(prefix, (ch)->device, "[%s] " fmt, \
89 		    (ch)->name, ##a)
90 
91 #define DPRINTK(fmt, arg...)						\
92 do {									\
93 	if (debug)							\
94 		ch_printk(KERN_DEBUG, ch, fmt, ##arg);			\
95 } while (0)
96 #define VPRINTK(level, fmt, arg...)					\
97 do {									\
98 	if (verbose)							\
99 		ch_printk(level, ch, fmt, ##arg);			\
100 } while (0)
101 
102 /* ------------------------------------------------------------------- */
103 
104 #define MAX_RETRIES   1
105 
106 static struct class * ch_sysfs_class;
107 
108 typedef struct {
109 	struct list_head    list;
110 	int                 minor;
111 	char                name[8];
112 	struct scsi_device  *device;
113 	struct scsi_device  **dt;        /* ptrs to data transfer elements */
114 	u_int               firsts[CH_TYPES];
115 	u_int               counts[CH_TYPES];
116 	u_int               unit_attention;
117 	u_int		    voltags;
118 	struct mutex	    lock;
119 } scsi_changer;
120 
121 static DEFINE_IDR(ch_index_idr);
122 static DEFINE_SPINLOCK(ch_index_lock);
123 
124 static const struct {
125 	unsigned char  sense;
126 	unsigned char  asc;
127 	unsigned char  ascq;
128 	int	       errno;
129 } ch_err[] = {
130 /* Just filled in what looks right. Hav'nt checked any standard paper for
131    these errno assignments, so they may be wrong... */
132 	{
133 		.sense  = ILLEGAL_REQUEST,
134 		.asc    = 0x21,
135 		.ascq   = 0x01,
136 		.errno  = EBADSLT, /* Invalid element address */
137 	},{
138 		.sense  = ILLEGAL_REQUEST,
139 		.asc    = 0x28,
140 		.ascq   = 0x01,
141 		.errno  = EBADE,   /* Import or export element accessed */
142 	},{
143 		.sense  = ILLEGAL_REQUEST,
144 		.asc    = 0x3B,
145 		.ascq   = 0x0D,
146 		.errno  = EXFULL,  /* Medium destination element full */
147 	},{
148 		.sense  = ILLEGAL_REQUEST,
149 		.asc    = 0x3B,
150 		.ascq   = 0x0E,
151 		.errno  = EBADE,   /* Medium source element empty */
152 	},{
153 		.sense  = ILLEGAL_REQUEST,
154 		.asc    = 0x20,
155 		.ascq   = 0x00,
156 		.errno  = EBADRQC, /* Invalid command operation code */
157 	},{
158 	        /* end of list */
159 	}
160 };
161 
162 /* ------------------------------------------------------------------- */
163 
164 static int ch_find_errno(struct scsi_sense_hdr *sshdr)
165 {
166 	int i,errno = 0;
167 
168 	/* Check to see if additional sense information is available */
169 	if (scsi_sense_valid(sshdr) &&
170 	    sshdr->asc != 0) {
171 		for (i = 0; ch_err[i].errno != 0; i++) {
172 			if (ch_err[i].sense == sshdr->sense_key &&
173 			    ch_err[i].asc   == sshdr->asc &&
174 			    ch_err[i].ascq  == sshdr->ascq) {
175 				errno = -ch_err[i].errno;
176 				break;
177 			}
178 		}
179 	}
180 	if (errno == 0)
181 		errno = -EIO;
182 	return errno;
183 }
184 
185 static int
186 ch_do_scsi(scsi_changer *ch, unsigned char *cmd,
187 	   void *buffer, unsigned buflength,
188 	   enum dma_data_direction direction)
189 {
190 	int errno, retries = 0, timeout, result;
191 	struct scsi_sense_hdr sshdr;
192 
193 	timeout = (cmd[0] == INITIALIZE_ELEMENT_STATUS)
194 		? timeout_init : timeout_move;
195 
196  retry:
197 	errno = 0;
198 	if (debug) {
199 		DPRINTK("command: ");
200 		__scsi_print_command(cmd);
201 	}
202 
203 	result = scsi_execute_req(ch->device, cmd, direction, buffer,
204 				  buflength, &sshdr, timeout * HZ,
205 				  MAX_RETRIES, NULL);
206 
207 	DPRINTK("result: 0x%x\n",result);
208 	if (driver_byte(result) & DRIVER_SENSE) {
209 		if (debug)
210 			scsi_print_sense_hdr(ch->name, &sshdr);
211 		errno = ch_find_errno(&sshdr);
212 
213 		switch(sshdr.sense_key) {
214 		case UNIT_ATTENTION:
215 			ch->unit_attention = 1;
216 			if (retries++ < 3)
217 				goto retry;
218 			break;
219 		}
220 	}
221 	return errno;
222 }
223 
224 /* ------------------------------------------------------------------------ */
225 
226 static int
227 ch_elem_to_typecode(scsi_changer *ch, u_int elem)
228 {
229 	int i;
230 
231 	for (i = 0; i < CH_TYPES; i++) {
232 		if (elem >= ch->firsts[i]  &&
233 		    elem <  ch->firsts[i] +
234 	            ch->counts[i])
235 			return i+1;
236 	}
237 	return 0;
238 }
239 
240 static int
241 ch_read_element_status(scsi_changer *ch, u_int elem, char *data)
242 {
243 	u_char  cmd[12];
244 	u_char  *buffer;
245 	int     result;
246 
247 	buffer = kmalloc(512, GFP_KERNEL | GFP_DMA);
248 	if(!buffer)
249 		return -ENOMEM;
250 
251  retry:
252 	memset(cmd,0,sizeof(cmd));
253 	cmd[0] = READ_ELEMENT_STATUS;
254 	cmd[1] = ((ch->device->lun & 0x7) << 5) |
255 		(ch->voltags ? 0x10 : 0) |
256 		ch_elem_to_typecode(ch,elem);
257 	cmd[2] = (elem >> 8) & 0xff;
258 	cmd[3] = elem        & 0xff;
259 	cmd[5] = 1;
260 	cmd[9] = 255;
261 	if (0 == (result = ch_do_scsi(ch, cmd, buffer, 256, DMA_FROM_DEVICE))) {
262 		if (((buffer[16] << 8) | buffer[17]) != elem) {
263 			DPRINTK("asked for element 0x%02x, got 0x%02x\n",
264 				elem,(buffer[16] << 8) | buffer[17]);
265 			kfree(buffer);
266 			return -EIO;
267 		}
268 		memcpy(data,buffer+16,16);
269 	} else {
270 		if (ch->voltags) {
271 			ch->voltags = 0;
272 			VPRINTK(KERN_INFO, "device has no volume tag support\n");
273 			goto retry;
274 		}
275 		DPRINTK("READ ELEMENT STATUS for element 0x%x failed\n",elem);
276 	}
277 	kfree(buffer);
278 	return result;
279 }
280 
281 static int
282 ch_init_elem(scsi_changer *ch)
283 {
284 	int err;
285 	u_char cmd[6];
286 
287 	VPRINTK(KERN_INFO, "INITIALIZE ELEMENT STATUS, may take some time ...\n");
288 	memset(cmd,0,sizeof(cmd));
289 	cmd[0] = INITIALIZE_ELEMENT_STATUS;
290 	cmd[1] = (ch->device->lun & 0x7) << 5;
291 	err = ch_do_scsi(ch, cmd, NULL, 0, DMA_NONE);
292 	VPRINTK(KERN_INFO, "... finished\n");
293 	return err;
294 }
295 
296 static int
297 ch_readconfig(scsi_changer *ch)
298 {
299 	u_char  cmd[10], data[16];
300 	u_char  *buffer;
301 	int     result,id,lun,i;
302 	u_int   elem;
303 
304 	buffer = kzalloc(512, GFP_KERNEL | GFP_DMA);
305 	if (!buffer)
306 		return -ENOMEM;
307 
308 	memset(cmd,0,sizeof(cmd));
309 	cmd[0] = MODE_SENSE;
310 	cmd[1] = (ch->device->lun & 0x7) << 5;
311 	cmd[2] = 0x1d;
312 	cmd[4] = 255;
313 	result = ch_do_scsi(ch, cmd, buffer, 255, DMA_FROM_DEVICE);
314 	if (0 != result) {
315 		cmd[1] |= (1<<3);
316 		result  = ch_do_scsi(ch, cmd, buffer, 255, DMA_FROM_DEVICE);
317 	}
318 	if (0 == result) {
319 		ch->firsts[CHET_MT] =
320 			(buffer[buffer[3]+ 6] << 8) | buffer[buffer[3]+ 7];
321 		ch->counts[CHET_MT] =
322 			(buffer[buffer[3]+ 8] << 8) | buffer[buffer[3]+ 9];
323 		ch->firsts[CHET_ST] =
324 			(buffer[buffer[3]+10] << 8) | buffer[buffer[3]+11];
325 		ch->counts[CHET_ST] =
326 			(buffer[buffer[3]+12] << 8) | buffer[buffer[3]+13];
327 		ch->firsts[CHET_IE] =
328 			(buffer[buffer[3]+14] << 8) | buffer[buffer[3]+15];
329 		ch->counts[CHET_IE] =
330 			(buffer[buffer[3]+16] << 8) | buffer[buffer[3]+17];
331 		ch->firsts[CHET_DT] =
332 			(buffer[buffer[3]+18] << 8) | buffer[buffer[3]+19];
333 		ch->counts[CHET_DT] =
334 			(buffer[buffer[3]+20] << 8) | buffer[buffer[3]+21];
335 		VPRINTK(KERN_INFO, "type #1 (mt): 0x%x+%d [medium transport]\n",
336 			ch->firsts[CHET_MT],
337 			ch->counts[CHET_MT]);
338 		VPRINTK(KERN_INFO, "type #2 (st): 0x%x+%d [storage]\n",
339 			ch->firsts[CHET_ST],
340 			ch->counts[CHET_ST]);
341 		VPRINTK(KERN_INFO, "type #3 (ie): 0x%x+%d [import/export]\n",
342 			ch->firsts[CHET_IE],
343 			ch->counts[CHET_IE]);
344 		VPRINTK(KERN_INFO, "type #4 (dt): 0x%x+%d [data transfer]\n",
345 			ch->firsts[CHET_DT],
346 			ch->counts[CHET_DT]);
347 	} else {
348 		VPRINTK(KERN_INFO, "reading element address assigment page failed!\n");
349 	}
350 
351 	/* vendor specific element types */
352 	for (i = 0; i < 4; i++) {
353 		if (0 == vendor_counts[i])
354 			continue;
355 		if (NULL == vendor_labels[i])
356 			continue;
357 		ch->firsts[CHET_V1+i] = vendor_firsts[i];
358 		ch->counts[CHET_V1+i] = vendor_counts[i];
359 		VPRINTK(KERN_INFO, "type #%d (v%d): 0x%x+%d [%s, vendor specific]\n",
360 			i+5,i+1,vendor_firsts[i],vendor_counts[i],
361 			vendor_labels[i]);
362 	}
363 
364 	/* look up the devices of the data transfer elements */
365 	ch->dt = kcalloc(ch->counts[CHET_DT], sizeof(*ch->dt),
366 			 GFP_KERNEL);
367 
368 	if (!ch->dt) {
369 		kfree(buffer);
370 		return -ENOMEM;
371 	}
372 
373 	for (elem = 0; elem < ch->counts[CHET_DT]; elem++) {
374 		id  = -1;
375 		lun = 0;
376 		if (elem < CH_DT_MAX  &&  -1 != dt_id[elem]) {
377 			id  = dt_id[elem];
378 			lun = dt_lun[elem];
379 			VPRINTK(KERN_INFO, "dt 0x%x: [insmod option] ",
380 				elem+ch->firsts[CHET_DT]);
381 		} else if (0 != ch_read_element_status
382 			   (ch,elem+ch->firsts[CHET_DT],data)) {
383 			VPRINTK(KERN_INFO, "dt 0x%x: READ ELEMENT STATUS failed\n",
384 				elem+ch->firsts[CHET_DT]);
385 		} else {
386 			VPRINTK(KERN_INFO, "dt 0x%x: ",elem+ch->firsts[CHET_DT]);
387 			if (data[6] & 0x80) {
388 				VPRINTK(KERN_CONT, "not this SCSI bus\n");
389 				ch->dt[elem] = NULL;
390 			} else if (0 == (data[6] & 0x30)) {
391 				VPRINTK(KERN_CONT, "ID/LUN unknown\n");
392 				ch->dt[elem] = NULL;
393 			} else {
394 				id  = ch->device->id;
395 				lun = 0;
396 				if (data[6] & 0x20) id  = data[7];
397 				if (data[6] & 0x10) lun = data[6] & 7;
398 			}
399 		}
400 		if (-1 != id) {
401 			VPRINTK(KERN_CONT, "ID %i, LUN %i, ",id,lun);
402 			ch->dt[elem] =
403 				scsi_device_lookup(ch->device->host,
404 						   ch->device->channel,
405 						   id,lun);
406 			if (!ch->dt[elem]) {
407 				/* should not happen */
408 				VPRINTK(KERN_CONT, "Huh? device not found!\n");
409 			} else {
410 				VPRINTK(KERN_CONT, "name: %8.8s %16.16s %4.4s\n",
411 					ch->dt[elem]->vendor,
412 					ch->dt[elem]->model,
413 					ch->dt[elem]->rev);
414 			}
415 		}
416 	}
417 	ch->voltags = 1;
418 	kfree(buffer);
419 
420 	return 0;
421 }
422 
423 /* ------------------------------------------------------------------------ */
424 
425 static int
426 ch_position(scsi_changer *ch, u_int trans, u_int elem, int rotate)
427 {
428 	u_char  cmd[10];
429 
430 	DPRINTK("position: 0x%x\n",elem);
431 	if (0 == trans)
432 		trans = ch->firsts[CHET_MT];
433 	memset(cmd,0,sizeof(cmd));
434 	cmd[0]  = POSITION_TO_ELEMENT;
435 	cmd[1]  = (ch->device->lun & 0x7) << 5;
436 	cmd[2]  = (trans >> 8) & 0xff;
437 	cmd[3]  =  trans       & 0xff;
438 	cmd[4]  = (elem  >> 8) & 0xff;
439 	cmd[5]  =  elem        & 0xff;
440 	cmd[8]  = rotate ? 1 : 0;
441 	return ch_do_scsi(ch, cmd, NULL, 0, DMA_NONE);
442 }
443 
444 static int
445 ch_move(scsi_changer *ch, u_int trans, u_int src, u_int dest, int rotate)
446 {
447 	u_char  cmd[12];
448 
449 	DPRINTK("move: 0x%x => 0x%x\n",src,dest);
450 	if (0 == trans)
451 		trans = ch->firsts[CHET_MT];
452 	memset(cmd,0,sizeof(cmd));
453 	cmd[0]  = MOVE_MEDIUM;
454 	cmd[1]  = (ch->device->lun & 0x7) << 5;
455 	cmd[2]  = (trans >> 8) & 0xff;
456 	cmd[3]  =  trans       & 0xff;
457 	cmd[4]  = (src   >> 8) & 0xff;
458 	cmd[5]  =  src         & 0xff;
459 	cmd[6]  = (dest  >> 8) & 0xff;
460 	cmd[7]  =  dest        & 0xff;
461 	cmd[10] = rotate ? 1 : 0;
462 	return ch_do_scsi(ch, cmd, NULL,0, DMA_NONE);
463 }
464 
465 static int
466 ch_exchange(scsi_changer *ch, u_int trans, u_int src,
467 	    u_int dest1, u_int dest2, int rotate1, int rotate2)
468 {
469 	u_char  cmd[12];
470 
471 	DPRINTK("exchange: 0x%x => 0x%x => 0x%x\n",
472 		src,dest1,dest2);
473 	if (0 == trans)
474 		trans = ch->firsts[CHET_MT];
475 	memset(cmd,0,sizeof(cmd));
476 	cmd[0]  = EXCHANGE_MEDIUM;
477 	cmd[1]  = (ch->device->lun & 0x7) << 5;
478 	cmd[2]  = (trans >> 8) & 0xff;
479 	cmd[3]  =  trans       & 0xff;
480 	cmd[4]  = (src   >> 8) & 0xff;
481 	cmd[5]  =  src         & 0xff;
482 	cmd[6]  = (dest1 >> 8) & 0xff;
483 	cmd[7]  =  dest1       & 0xff;
484 	cmd[8]  = (dest2 >> 8) & 0xff;
485 	cmd[9]  =  dest2       & 0xff;
486 	cmd[10] = (rotate1 ? 1 : 0) | (rotate2 ? 2 : 0);
487 
488 	return ch_do_scsi(ch, cmd, NULL,0, DMA_NONE);
489 }
490 
491 static void
492 ch_check_voltag(char *tag)
493 {
494 	int i;
495 
496 	for (i = 0; i < 32; i++) {
497 		/* restrict to ascii */
498 		if (tag[i] >= 0x7f || tag[i] < 0x20)
499 			tag[i] = ' ';
500 		/* don't allow search wildcards */
501 		if (tag[i] == '?' ||
502 		    tag[i] == '*')
503 			tag[i] = ' ';
504 	}
505 }
506 
507 static int
508 ch_set_voltag(scsi_changer *ch, u_int elem,
509 	      int alternate, int clear, u_char *tag)
510 {
511 	u_char  cmd[12];
512 	u_char  *buffer;
513 	int result;
514 
515 	buffer = kzalloc(512, GFP_KERNEL);
516 	if (!buffer)
517 		return -ENOMEM;
518 
519 	DPRINTK("%s %s voltag: 0x%x => \"%s\"\n",
520 		clear     ? "clear"     : "set",
521 		alternate ? "alternate" : "primary",
522 		elem, tag);
523 	memset(cmd,0,sizeof(cmd));
524 	cmd[0]  = SEND_VOLUME_TAG;
525 	cmd[1] = ((ch->device->lun & 0x7) << 5) |
526 		ch_elem_to_typecode(ch,elem);
527 	cmd[2] = (elem >> 8) & 0xff;
528 	cmd[3] = elem        & 0xff;
529 	cmd[5] = clear
530 		? (alternate ? 0x0d : 0x0c)
531 		: (alternate ? 0x0b : 0x0a);
532 
533 	cmd[9] = 255;
534 
535 	memcpy(buffer,tag,32);
536 	ch_check_voltag(buffer);
537 
538 	result = ch_do_scsi(ch, cmd, buffer, 256, DMA_TO_DEVICE);
539 	kfree(buffer);
540 	return result;
541 }
542 
543 static int ch_gstatus(scsi_changer *ch, int type, unsigned char __user *dest)
544 {
545 	int retval = 0;
546 	u_char data[16];
547 	unsigned int i;
548 
549 	mutex_lock(&ch->lock);
550 	for (i = 0; i < ch->counts[type]; i++) {
551 		if (0 != ch_read_element_status
552 		    (ch, ch->firsts[type]+i,data)) {
553 			retval = -EIO;
554 			break;
555 		}
556 		put_user(data[2], dest+i);
557 		if (data[2] & CESTATUS_EXCEPT)
558 			VPRINTK(KERN_INFO, "element 0x%x: asc=0x%x, ascq=0x%x\n",
559 				ch->firsts[type]+i,
560 				(int)data[4],(int)data[5]);
561 		retval = ch_read_element_status
562 			(ch, ch->firsts[type]+i,data);
563 		if (0 != retval)
564 			break;
565 	}
566 	mutex_unlock(&ch->lock);
567 	return retval;
568 }
569 
570 /* ------------------------------------------------------------------------ */
571 
572 static int
573 ch_release(struct inode *inode, struct file *file)
574 {
575 	scsi_changer *ch = file->private_data;
576 
577 	scsi_device_put(ch->device);
578 	file->private_data = NULL;
579 	return 0;
580 }
581 
582 static int
583 ch_open(struct inode *inode, struct file *file)
584 {
585 	scsi_changer *ch;
586 	int minor = iminor(inode);
587 
588 	mutex_lock(&ch_mutex);
589 	spin_lock(&ch_index_lock);
590 	ch = idr_find(&ch_index_idr, minor);
591 
592 	if (NULL == ch || scsi_device_get(ch->device)) {
593 		spin_unlock(&ch_index_lock);
594 		mutex_unlock(&ch_mutex);
595 		return -ENXIO;
596 	}
597 	spin_unlock(&ch_index_lock);
598 
599 	file->private_data = ch;
600 	mutex_unlock(&ch_mutex);
601 	return 0;
602 }
603 
604 static int
605 ch_checkrange(scsi_changer *ch, unsigned int type, unsigned int unit)
606 {
607 	if (type >= CH_TYPES  ||  unit >= ch->counts[type])
608 		return -1;
609 	return 0;
610 }
611 
612 static long ch_ioctl(struct file *file,
613 		    unsigned int cmd, unsigned long arg)
614 {
615 	scsi_changer *ch = file->private_data;
616 	int retval;
617 	void __user *argp = (void __user *)arg;
618 
619 	switch (cmd) {
620 	case CHIOGPARAMS:
621 	{
622 		struct changer_params params;
623 
624 		params.cp_curpicker = 0;
625 		params.cp_npickers  = ch->counts[CHET_MT];
626 		params.cp_nslots    = ch->counts[CHET_ST];
627 		params.cp_nportals  = ch->counts[CHET_IE];
628 		params.cp_ndrives   = ch->counts[CHET_DT];
629 
630 		if (copy_to_user(argp, &params, sizeof(params)))
631 			return -EFAULT;
632 		return 0;
633 	}
634 	case CHIOGVPARAMS:
635 	{
636 		struct changer_vendor_params vparams;
637 
638 		memset(&vparams,0,sizeof(vparams));
639 		if (ch->counts[CHET_V1]) {
640 			vparams.cvp_n1  = ch->counts[CHET_V1];
641 			strncpy(vparams.cvp_label1,vendor_labels[0],16);
642 		}
643 		if (ch->counts[CHET_V2]) {
644 			vparams.cvp_n2  = ch->counts[CHET_V2];
645 			strncpy(vparams.cvp_label2,vendor_labels[1],16);
646 		}
647 		if (ch->counts[CHET_V3]) {
648 			vparams.cvp_n3  = ch->counts[CHET_V3];
649 			strncpy(vparams.cvp_label3,vendor_labels[2],16);
650 		}
651 		if (ch->counts[CHET_V4]) {
652 			vparams.cvp_n4  = ch->counts[CHET_V4];
653 			strncpy(vparams.cvp_label4,vendor_labels[3],16);
654 		}
655 		if (copy_to_user(argp, &vparams, sizeof(vparams)))
656 			return -EFAULT;
657 		return 0;
658 	}
659 
660 	case CHIOPOSITION:
661 	{
662 		struct changer_position pos;
663 
664 		if (copy_from_user(&pos, argp, sizeof (pos)))
665 			return -EFAULT;
666 
667 		if (0 != ch_checkrange(ch, pos.cp_type, pos.cp_unit)) {
668 			DPRINTK("CHIOPOSITION: invalid parameter\n");
669 			return -EBADSLT;
670 		}
671 		mutex_lock(&ch->lock);
672 		retval = ch_position(ch,0,
673 				     ch->firsts[pos.cp_type] + pos.cp_unit,
674 				     pos.cp_flags & CP_INVERT);
675 		mutex_unlock(&ch->lock);
676 		return retval;
677 	}
678 
679 	case CHIOMOVE:
680 	{
681 		struct changer_move mv;
682 
683 		if (copy_from_user(&mv, argp, sizeof (mv)))
684 			return -EFAULT;
685 
686 		if (0 != ch_checkrange(ch, mv.cm_fromtype, mv.cm_fromunit) ||
687 		    0 != ch_checkrange(ch, mv.cm_totype,   mv.cm_tounit  )) {
688 			DPRINTK("CHIOMOVE: invalid parameter\n");
689 			return -EBADSLT;
690 		}
691 
692 		mutex_lock(&ch->lock);
693 		retval = ch_move(ch,0,
694 				 ch->firsts[mv.cm_fromtype] + mv.cm_fromunit,
695 				 ch->firsts[mv.cm_totype]   + mv.cm_tounit,
696 				 mv.cm_flags & CM_INVERT);
697 		mutex_unlock(&ch->lock);
698 		return retval;
699 	}
700 
701 	case CHIOEXCHANGE:
702 	{
703 		struct changer_exchange mv;
704 
705 		if (copy_from_user(&mv, argp, sizeof (mv)))
706 			return -EFAULT;
707 
708 		if (0 != ch_checkrange(ch, mv.ce_srctype,  mv.ce_srcunit ) ||
709 		    0 != ch_checkrange(ch, mv.ce_fdsttype, mv.ce_fdstunit) ||
710 		    0 != ch_checkrange(ch, mv.ce_sdsttype, mv.ce_sdstunit)) {
711 			DPRINTK("CHIOEXCHANGE: invalid parameter\n");
712 			return -EBADSLT;
713 		}
714 
715 		mutex_lock(&ch->lock);
716 		retval = ch_exchange
717 			(ch,0,
718 			 ch->firsts[mv.ce_srctype]  + mv.ce_srcunit,
719 			 ch->firsts[mv.ce_fdsttype] + mv.ce_fdstunit,
720 			 ch->firsts[mv.ce_sdsttype] + mv.ce_sdstunit,
721 			 mv.ce_flags & CE_INVERT1, mv.ce_flags & CE_INVERT2);
722 		mutex_unlock(&ch->lock);
723 		return retval;
724 	}
725 
726 	case CHIOGSTATUS:
727 	{
728 		struct changer_element_status ces;
729 
730 		if (copy_from_user(&ces, argp, sizeof (ces)))
731 			return -EFAULT;
732 		if (ces.ces_type < 0 || ces.ces_type >= CH_TYPES)
733 			return -EINVAL;
734 
735 		return ch_gstatus(ch, ces.ces_type, ces.ces_data);
736 	}
737 
738 	case CHIOGELEM:
739 	{
740 		struct changer_get_element cge;
741 		u_char ch_cmd[12];
742 		u_char *buffer;
743 		unsigned int elem;
744 		int     result,i;
745 
746 		if (copy_from_user(&cge, argp, sizeof (cge)))
747 			return -EFAULT;
748 
749 		if (0 != ch_checkrange(ch, cge.cge_type, cge.cge_unit))
750 			return -EINVAL;
751 		elem = ch->firsts[cge.cge_type] + cge.cge_unit;
752 
753 		buffer = kmalloc(512, GFP_KERNEL | GFP_DMA);
754 		if (!buffer)
755 			return -ENOMEM;
756 		mutex_lock(&ch->lock);
757 
758 	voltag_retry:
759 		memset(ch_cmd, 0, sizeof(ch_cmd));
760 		ch_cmd[0] = READ_ELEMENT_STATUS;
761 		ch_cmd[1] = ((ch->device->lun & 0x7) << 5) |
762 			(ch->voltags ? 0x10 : 0) |
763 			ch_elem_to_typecode(ch,elem);
764 		ch_cmd[2] = (elem >> 8) & 0xff;
765 		ch_cmd[3] = elem        & 0xff;
766 		ch_cmd[5] = 1;
767 		ch_cmd[9] = 255;
768 
769 		result = ch_do_scsi(ch, ch_cmd, buffer, 256, DMA_FROM_DEVICE);
770 		if (!result) {
771 			cge.cge_status = buffer[18];
772 			cge.cge_flags = 0;
773 			if (buffer[18] & CESTATUS_EXCEPT) {
774 				cge.cge_errno = EIO;
775 			}
776 			if (buffer[25] & 0x80) {
777 				cge.cge_flags |= CGE_SRC;
778 				if (buffer[25] & 0x40)
779 					cge.cge_flags |= CGE_INVERT;
780 				elem = (buffer[26]<<8) | buffer[27];
781 				for (i = 0; i < 4; i++) {
782 					if (elem >= ch->firsts[i] &&
783 					    elem <  ch->firsts[i] + ch->counts[i]) {
784 						cge.cge_srctype = i;
785 						cge.cge_srcunit = elem-ch->firsts[i];
786 					}
787 				}
788 			}
789 			if ((buffer[22] & 0x30) == 0x30) {
790 				cge.cge_flags |= CGE_IDLUN;
791 				cge.cge_id  = buffer[23];
792 				cge.cge_lun = buffer[22] & 7;
793 			}
794 			if (buffer[9] & 0x80) {
795 				cge.cge_flags |= CGE_PVOLTAG;
796 				memcpy(cge.cge_pvoltag,buffer+28,36);
797 			}
798 			if (buffer[9] & 0x40) {
799 				cge.cge_flags |= CGE_AVOLTAG;
800 				memcpy(cge.cge_avoltag,buffer+64,36);
801 			}
802 		} else if (ch->voltags) {
803 			ch->voltags = 0;
804 			VPRINTK(KERN_INFO, "device has no volume tag support\n");
805 			goto voltag_retry;
806 		}
807 		kfree(buffer);
808 		mutex_unlock(&ch->lock);
809 
810 		if (copy_to_user(argp, &cge, sizeof (cge)))
811 			return -EFAULT;
812 		return result;
813 	}
814 
815 	case CHIOINITELEM:
816 	{
817 		mutex_lock(&ch->lock);
818 		retval = ch_init_elem(ch);
819 		mutex_unlock(&ch->lock);
820 		return retval;
821 	}
822 
823 	case CHIOSVOLTAG:
824 	{
825 		struct changer_set_voltag csv;
826 		int elem;
827 
828 		if (copy_from_user(&csv, argp, sizeof(csv)))
829 			return -EFAULT;
830 
831 		if (0 != ch_checkrange(ch, csv.csv_type, csv.csv_unit)) {
832 			DPRINTK("CHIOSVOLTAG: invalid parameter\n");
833 			return -EBADSLT;
834 		}
835 		elem = ch->firsts[csv.csv_type] + csv.csv_unit;
836 		mutex_lock(&ch->lock);
837 		retval = ch_set_voltag(ch, elem,
838 				       csv.csv_flags & CSV_AVOLTAG,
839 				       csv.csv_flags & CSV_CLEARTAG,
840 				       csv.csv_voltag);
841 		mutex_unlock(&ch->lock);
842 		return retval;
843 	}
844 
845 	default:
846 		return scsi_ioctl(ch->device, cmd, argp);
847 
848 	}
849 }
850 
851 #ifdef CONFIG_COMPAT
852 
853 struct changer_element_status32 {
854 	int		ces_type;
855 	compat_uptr_t	ces_data;
856 };
857 #define CHIOGSTATUS32  _IOW('c', 8,struct changer_element_status32)
858 
859 static long ch_ioctl_compat(struct file * file,
860 			    unsigned int cmd, unsigned long arg)
861 {
862 	scsi_changer *ch = file->private_data;
863 
864 	switch (cmd) {
865 	case CHIOGPARAMS:
866 	case CHIOGVPARAMS:
867 	case CHIOPOSITION:
868 	case CHIOMOVE:
869 	case CHIOEXCHANGE:
870 	case CHIOGELEM:
871 	case CHIOINITELEM:
872 	case CHIOSVOLTAG:
873 		/* compatible */
874 		return ch_ioctl(file, cmd, arg);
875 	case CHIOGSTATUS32:
876 	{
877 		struct changer_element_status32 ces32;
878 		unsigned char __user *data;
879 
880 		if (copy_from_user(&ces32, (void __user *)arg, sizeof (ces32)))
881 			return -EFAULT;
882 		if (ces32.ces_type < 0 || ces32.ces_type >= CH_TYPES)
883 			return -EINVAL;
884 
885 		data = compat_ptr(ces32.ces_data);
886 		return ch_gstatus(ch, ces32.ces_type, data);
887 	}
888 	default:
889 		// return scsi_ioctl_compat(ch->device, cmd, (void*)arg);
890 		return -ENOIOCTLCMD;
891 
892 	}
893 }
894 #endif
895 
896 /* ------------------------------------------------------------------------ */
897 
898 static int ch_probe(struct device *dev)
899 {
900 	struct scsi_device *sd = to_scsi_device(dev);
901 	struct device *class_dev;
902 	int ret;
903 	scsi_changer *ch;
904 
905 	if (sd->type != TYPE_MEDIUM_CHANGER)
906 		return -ENODEV;
907 
908 	ch = kzalloc(sizeof(*ch), GFP_KERNEL);
909 	if (NULL == ch)
910 		return -ENOMEM;
911 
912 	idr_preload(GFP_KERNEL);
913 	spin_lock(&ch_index_lock);
914 	ret = idr_alloc(&ch_index_idr, ch, 0, CH_MAX_DEVS + 1, GFP_NOWAIT);
915 	spin_unlock(&ch_index_lock);
916 	idr_preload_end();
917 
918 	if (ret < 0) {
919 		if (ret == -ENOSPC)
920 			ret = -ENODEV;
921 		goto free_ch;
922 	}
923 
924 	ch->minor = ret;
925 	sprintf(ch->name,"ch%d",ch->minor);
926 
927 	class_dev = device_create(ch_sysfs_class, dev,
928 				  MKDEV(SCSI_CHANGER_MAJOR, ch->minor), ch,
929 				  "s%s", ch->name);
930 	if (IS_ERR(class_dev)) {
931 		sdev_printk(KERN_WARNING, sd, "ch%d: device_create failed\n",
932 			    ch->minor);
933 		ret = PTR_ERR(class_dev);
934 		goto remove_idr;
935 	}
936 
937 	mutex_init(&ch->lock);
938 	ch->device = sd;
939 	ch_readconfig(ch);
940 	if (init)
941 		ch_init_elem(ch);
942 
943 	dev_set_drvdata(dev, ch);
944 	sdev_printk(KERN_INFO, sd, "Attached scsi changer %s\n", ch->name);
945 
946 	return 0;
947 remove_idr:
948 	idr_remove(&ch_index_idr, ch->minor);
949 free_ch:
950 	kfree(ch);
951 	return ret;
952 }
953 
954 static int ch_remove(struct device *dev)
955 {
956 	scsi_changer *ch = dev_get_drvdata(dev);
957 
958 	spin_lock(&ch_index_lock);
959 	idr_remove(&ch_index_idr, ch->minor);
960 	spin_unlock(&ch_index_lock);
961 
962 	device_destroy(ch_sysfs_class, MKDEV(SCSI_CHANGER_MAJOR,ch->minor));
963 	kfree(ch->dt);
964 	kfree(ch);
965 	return 0;
966 }
967 
968 static struct scsi_driver ch_template = {
969 	.owner     	= THIS_MODULE,
970 	.gendrv     	= {
971 		.name	= "ch",
972 		.probe  = ch_probe,
973 		.remove = ch_remove,
974 	},
975 };
976 
977 static const struct file_operations changer_fops = {
978 	.owner		= THIS_MODULE,
979 	.open		= ch_open,
980 	.release	= ch_release,
981 	.unlocked_ioctl	= ch_ioctl,
982 #ifdef CONFIG_COMPAT
983 	.compat_ioctl	= ch_ioctl_compat,
984 #endif
985 	.llseek		= noop_llseek,
986 };
987 
988 static int __init init_ch_module(void)
989 {
990 	int rc;
991 
992 	printk(KERN_INFO "SCSI Media Changer driver v" VERSION " \n");
993         ch_sysfs_class = class_create(THIS_MODULE, "scsi_changer");
994         if (IS_ERR(ch_sysfs_class)) {
995 		rc = PTR_ERR(ch_sysfs_class);
996 		return rc;
997         }
998 	rc = register_chrdev(SCSI_CHANGER_MAJOR,"ch",&changer_fops);
999 	if (rc < 0) {
1000 		printk("Unable to get major %d for SCSI-Changer\n",
1001 		       SCSI_CHANGER_MAJOR);
1002 		goto fail1;
1003 	}
1004 	rc = scsi_register_driver(&ch_template.gendrv);
1005 	if (rc < 0)
1006 		goto fail2;
1007 	return 0;
1008 
1009  fail2:
1010 	unregister_chrdev(SCSI_CHANGER_MAJOR, "ch");
1011  fail1:
1012 	class_destroy(ch_sysfs_class);
1013 	return rc;
1014 }
1015 
1016 static void __exit exit_ch_module(void)
1017 {
1018 	scsi_unregister_driver(&ch_template.gendrv);
1019 	unregister_chrdev(SCSI_CHANGER_MAJOR, "ch");
1020 	class_destroy(ch_sysfs_class);
1021 	idr_destroy(&ch_index_idr);
1022 }
1023 
1024 module_init(init_ch_module);
1025 module_exit(exit_ch_module);
1026 
1027 /*
1028  * Local variables:
1029  * c-basic-offset: 8
1030  * End:
1031  */
1032