xref: /openbmc/linux/drivers/scsi/ch.c (revision 1edd0337)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * SCSI Media Changer device driver for Linux 2.6
4  *
5  *     (c) 1996-2003 Gerd Knorr <kraxel@bytesex.org>
6  *
7  */
8 
9 #define VERSION "0.25"
10 
11 #include <linux/module.h>
12 #include <linux/init.h>
13 #include <linux/fs.h>
14 #include <linux/kernel.h>
15 #include <linux/mm.h>
16 #include <linux/major.h>
17 #include <linux/string.h>
18 #include <linux/errno.h>
19 #include <linux/interrupt.h>
20 #include <linux/blkdev.h>
21 #include <linux/completion.h>
22 #include <linux/compat.h>
23 #include <linux/chio.h>			/* here are all the ioctls */
24 #include <linux/mutex.h>
25 #include <linux/idr.h>
26 #include <linux/slab.h>
27 
28 #include <scsi/scsi.h>
29 #include <scsi/scsi_cmnd.h>
30 #include <scsi/scsi_driver.h>
31 #include <scsi/scsi_ioctl.h>
32 #include <scsi/scsi_host.h>
33 #include <scsi/scsi_device.h>
34 #include <scsi/scsi_eh.h>
35 #include <scsi/scsi_dbg.h>
36 
37 #define CH_DT_MAX       16
38 #define CH_TYPES        8
39 #define CH_MAX_DEVS     128
40 
41 MODULE_DESCRIPTION("device driver for scsi media changer devices");
42 MODULE_AUTHOR("Gerd Knorr <kraxel@bytesex.org>");
43 MODULE_LICENSE("GPL");
44 MODULE_ALIAS_CHARDEV_MAJOR(SCSI_CHANGER_MAJOR);
45 MODULE_ALIAS_SCSI_DEVICE(TYPE_MEDIUM_CHANGER);
46 
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;
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_prefix_printk(prefix, (ch)->device, (ch)->name, fmt, ##a)
89 
90 #define DPRINTK(fmt, arg...)						\
91 do {									\
92 	if (debug)							\
93 		ch_printk(KERN_DEBUG, ch, fmt, ##arg);			\
94 } while (0)
95 #define VPRINTK(level, fmt, arg...)					\
96 do {									\
97 	if (verbose)							\
98 		ch_printk(level, ch, fmt, ##arg);			\
99 } while (0)
100 
101 /* ------------------------------------------------------------------- */
102 
103 #define MAX_RETRIES   1
104 
105 static struct class * ch_sysfs_class;
106 
107 typedef struct {
108 	struct kref         ref;
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, int cmd_len,
187 	   void *buffer, unsigned int buflength, enum req_op op)
188 {
189 	int errno, retries = 0, timeout, result;
190 	struct scsi_sense_hdr sshdr;
191 	const struct scsi_exec_args exec_args = {
192 		.sshdr = &sshdr,
193 	};
194 
195 	timeout = (cmd[0] == INITIALIZE_ELEMENT_STATUS)
196 		? timeout_init : timeout_move;
197 
198  retry:
199 	errno = 0;
200 	result = scsi_execute_cmd(ch->device, cmd, op, buffer, buflength,
201 				  timeout * HZ, MAX_RETRIES, &exec_args);
202 	if (result < 0)
203 		return result;
204 	if (scsi_sense_valid(&sshdr)) {
205 		if (debug)
206 			scsi_print_sense_hdr(ch->device, ch->name, &sshdr);
207 		errno = ch_find_errno(&sshdr);
208 
209 		switch(sshdr.sense_key) {
210 		case UNIT_ATTENTION:
211 			ch->unit_attention = 1;
212 			if (retries++ < 3)
213 				goto retry;
214 			break;
215 		}
216 	}
217 	return errno;
218 }
219 
220 /* ------------------------------------------------------------------------ */
221 
222 static int
223 ch_elem_to_typecode(scsi_changer *ch, u_int elem)
224 {
225 	int i;
226 
227 	for (i = 0; i < CH_TYPES; i++) {
228 		if (elem >= ch->firsts[i]  &&
229 		    elem <  ch->firsts[i] +
230 	            ch->counts[i])
231 			return i+1;
232 	}
233 	return 0;
234 }
235 
236 static int
237 ch_read_element_status(scsi_changer *ch, u_int elem, char *data)
238 {
239 	u_char  cmd[12];
240 	u_char  *buffer;
241 	int     result;
242 
243 	buffer = kmalloc(512, GFP_KERNEL);
244 	if(!buffer)
245 		return -ENOMEM;
246 
247  retry:
248 	memset(cmd,0,sizeof(cmd));
249 	cmd[0] = READ_ELEMENT_STATUS;
250 	cmd[1] = ((ch->device->lun & 0x7) << 5) |
251 		(ch->voltags ? 0x10 : 0) |
252 		ch_elem_to_typecode(ch,elem);
253 	cmd[2] = (elem >> 8) & 0xff;
254 	cmd[3] = elem        & 0xff;
255 	cmd[5] = 1;
256 	cmd[9] = 255;
257 	if (0 == (result = ch_do_scsi(ch, cmd, 12,
258 				      buffer, 256, REQ_OP_DRV_IN))) {
259 		if (((buffer[16] << 8) | buffer[17]) != elem) {
260 			DPRINTK("asked for element 0x%02x, got 0x%02x\n",
261 				elem,(buffer[16] << 8) | buffer[17]);
262 			kfree(buffer);
263 			return -EIO;
264 		}
265 		memcpy(data,buffer+16,16);
266 	} else {
267 		if (ch->voltags) {
268 			ch->voltags = 0;
269 			VPRINTK(KERN_INFO, "device has no volume tag support\n");
270 			goto retry;
271 		}
272 		DPRINTK("READ ELEMENT STATUS for element 0x%x failed\n",elem);
273 	}
274 	kfree(buffer);
275 	return result;
276 }
277 
278 static int
279 ch_init_elem(scsi_changer *ch)
280 {
281 	int err;
282 	u_char cmd[6];
283 
284 	VPRINTK(KERN_INFO, "INITIALIZE ELEMENT STATUS, may take some time ...\n");
285 	memset(cmd,0,sizeof(cmd));
286 	cmd[0] = INITIALIZE_ELEMENT_STATUS;
287 	cmd[1] = (ch->device->lun & 0x7) << 5;
288 	err = ch_do_scsi(ch, cmd, 6, NULL, 0, REQ_OP_DRV_IN);
289 	VPRINTK(KERN_INFO, "... finished\n");
290 	return err;
291 }
292 
293 static int
294 ch_readconfig(scsi_changer *ch)
295 {
296 	u_char  cmd[10], data[16];
297 	u_char  *buffer;
298 	int     result,id,lun,i;
299 	u_int   elem;
300 
301 	buffer = kzalloc(512, GFP_KERNEL);
302 	if (!buffer)
303 		return -ENOMEM;
304 
305 	memset(cmd,0,sizeof(cmd));
306 	cmd[0] = MODE_SENSE;
307 	cmd[1] = (ch->device->lun & 0x7) << 5;
308 	cmd[2] = 0x1d;
309 	cmd[4] = 255;
310 	result = ch_do_scsi(ch, cmd, 10, buffer, 255, REQ_OP_DRV_IN);
311 	if (0 != result) {
312 		cmd[1] |= (1<<3);
313 		result  = ch_do_scsi(ch, cmd, 10, buffer, 255, REQ_OP_DRV_IN);
314 	}
315 	if (0 == result) {
316 		ch->firsts[CHET_MT] =
317 			(buffer[buffer[3]+ 6] << 8) | buffer[buffer[3]+ 7];
318 		ch->counts[CHET_MT] =
319 			(buffer[buffer[3]+ 8] << 8) | buffer[buffer[3]+ 9];
320 		ch->firsts[CHET_ST] =
321 			(buffer[buffer[3]+10] << 8) | buffer[buffer[3]+11];
322 		ch->counts[CHET_ST] =
323 			(buffer[buffer[3]+12] << 8) | buffer[buffer[3]+13];
324 		ch->firsts[CHET_IE] =
325 			(buffer[buffer[3]+14] << 8) | buffer[buffer[3]+15];
326 		ch->counts[CHET_IE] =
327 			(buffer[buffer[3]+16] << 8) | buffer[buffer[3]+17];
328 		ch->firsts[CHET_DT] =
329 			(buffer[buffer[3]+18] << 8) | buffer[buffer[3]+19];
330 		ch->counts[CHET_DT] =
331 			(buffer[buffer[3]+20] << 8) | buffer[buffer[3]+21];
332 		VPRINTK(KERN_INFO, "type #1 (mt): 0x%x+%d [medium transport]\n",
333 			ch->firsts[CHET_MT],
334 			ch->counts[CHET_MT]);
335 		VPRINTK(KERN_INFO, "type #2 (st): 0x%x+%d [storage]\n",
336 			ch->firsts[CHET_ST],
337 			ch->counts[CHET_ST]);
338 		VPRINTK(KERN_INFO, "type #3 (ie): 0x%x+%d [import/export]\n",
339 			ch->firsts[CHET_IE],
340 			ch->counts[CHET_IE]);
341 		VPRINTK(KERN_INFO, "type #4 (dt): 0x%x+%d [data transfer]\n",
342 			ch->firsts[CHET_DT],
343 			ch->counts[CHET_DT]);
344 	} else {
345 		VPRINTK(KERN_INFO, "reading element address assignment page failed!\n");
346 	}
347 
348 	/* vendor specific element types */
349 	for (i = 0; i < 4; i++) {
350 		if (0 == vendor_counts[i])
351 			continue;
352 		if (NULL == vendor_labels[i])
353 			continue;
354 		ch->firsts[CHET_V1+i] = vendor_firsts[i];
355 		ch->counts[CHET_V1+i] = vendor_counts[i];
356 		VPRINTK(KERN_INFO, "type #%d (v%d): 0x%x+%d [%s, vendor specific]\n",
357 			i+5,i+1,vendor_firsts[i],vendor_counts[i],
358 			vendor_labels[i]);
359 	}
360 
361 	/* look up the devices of the data transfer elements */
362 	ch->dt = kcalloc(ch->counts[CHET_DT], sizeof(*ch->dt),
363 			 GFP_KERNEL);
364 
365 	if (!ch->dt) {
366 		kfree(buffer);
367 		return -ENOMEM;
368 	}
369 
370 	for (elem = 0; elem < ch->counts[CHET_DT]; elem++) {
371 		id  = -1;
372 		lun = 0;
373 		if (elem < CH_DT_MAX  &&  -1 != dt_id[elem]) {
374 			id  = dt_id[elem];
375 			lun = dt_lun[elem];
376 			VPRINTK(KERN_INFO, "dt 0x%x: [insmod option] ",
377 				elem+ch->firsts[CHET_DT]);
378 		} else if (0 != ch_read_element_status
379 			   (ch,elem+ch->firsts[CHET_DT],data)) {
380 			VPRINTK(KERN_INFO, "dt 0x%x: READ ELEMENT STATUS failed\n",
381 				elem+ch->firsts[CHET_DT]);
382 		} else {
383 			VPRINTK(KERN_INFO, "dt 0x%x: ",elem+ch->firsts[CHET_DT]);
384 			if (data[6] & 0x80) {
385 				VPRINTK(KERN_CONT, "not this SCSI bus\n");
386 				ch->dt[elem] = NULL;
387 			} else if (0 == (data[6] & 0x30)) {
388 				VPRINTK(KERN_CONT, "ID/LUN unknown\n");
389 				ch->dt[elem] = NULL;
390 			} else {
391 				id  = ch->device->id;
392 				lun = 0;
393 				if (data[6] & 0x20) id  = data[7];
394 				if (data[6] & 0x10) lun = data[6] & 7;
395 			}
396 		}
397 		if (-1 != id) {
398 			VPRINTK(KERN_CONT, "ID %i, LUN %i, ",id,lun);
399 			ch->dt[elem] =
400 				scsi_device_lookup(ch->device->host,
401 						   ch->device->channel,
402 						   id,lun);
403 			if (!ch->dt[elem]) {
404 				/* should not happen */
405 				VPRINTK(KERN_CONT, "Huh? device not found!\n");
406 			} else {
407 				VPRINTK(KERN_CONT, "name: %8.8s %16.16s %4.4s\n",
408 					ch->dt[elem]->vendor,
409 					ch->dt[elem]->model,
410 					ch->dt[elem]->rev);
411 			}
412 		}
413 	}
414 	ch->voltags = 1;
415 	kfree(buffer);
416 
417 	return 0;
418 }
419 
420 /* ------------------------------------------------------------------------ */
421 
422 static int
423 ch_position(scsi_changer *ch, u_int trans, u_int elem, int rotate)
424 {
425 	u_char  cmd[10];
426 
427 	DPRINTK("position: 0x%x\n",elem);
428 	if (0 == trans)
429 		trans = ch->firsts[CHET_MT];
430 	memset(cmd,0,sizeof(cmd));
431 	cmd[0]  = POSITION_TO_ELEMENT;
432 	cmd[1]  = (ch->device->lun & 0x7) << 5;
433 	cmd[2]  = (trans >> 8) & 0xff;
434 	cmd[3]  =  trans       & 0xff;
435 	cmd[4]  = (elem  >> 8) & 0xff;
436 	cmd[5]  =  elem        & 0xff;
437 	cmd[8]  = rotate ? 1 : 0;
438 	return ch_do_scsi(ch, cmd, 10, NULL, 0, REQ_OP_DRV_IN);
439 }
440 
441 static int
442 ch_move(scsi_changer *ch, u_int trans, u_int src, u_int dest, int rotate)
443 {
444 	u_char  cmd[12];
445 
446 	DPRINTK("move: 0x%x => 0x%x\n",src,dest);
447 	if (0 == trans)
448 		trans = ch->firsts[CHET_MT];
449 	memset(cmd,0,sizeof(cmd));
450 	cmd[0]  = MOVE_MEDIUM;
451 	cmd[1]  = (ch->device->lun & 0x7) << 5;
452 	cmd[2]  = (trans >> 8) & 0xff;
453 	cmd[3]  =  trans       & 0xff;
454 	cmd[4]  = (src   >> 8) & 0xff;
455 	cmd[5]  =  src         & 0xff;
456 	cmd[6]  = (dest  >> 8) & 0xff;
457 	cmd[7]  =  dest        & 0xff;
458 	cmd[10] = rotate ? 1 : 0;
459 	return ch_do_scsi(ch, cmd, 12, NULL, 0, REQ_OP_DRV_IN);
460 }
461 
462 static int
463 ch_exchange(scsi_changer *ch, u_int trans, u_int src,
464 	    u_int dest1, u_int dest2, int rotate1, int rotate2)
465 {
466 	u_char  cmd[12];
467 
468 	DPRINTK("exchange: 0x%x => 0x%x => 0x%x\n",
469 		src,dest1,dest2);
470 	if (0 == trans)
471 		trans = ch->firsts[CHET_MT];
472 	memset(cmd,0,sizeof(cmd));
473 	cmd[0]  = EXCHANGE_MEDIUM;
474 	cmd[1]  = (ch->device->lun & 0x7) << 5;
475 	cmd[2]  = (trans >> 8) & 0xff;
476 	cmd[3]  =  trans       & 0xff;
477 	cmd[4]  = (src   >> 8) & 0xff;
478 	cmd[5]  =  src         & 0xff;
479 	cmd[6]  = (dest1 >> 8) & 0xff;
480 	cmd[7]  =  dest1       & 0xff;
481 	cmd[8]  = (dest2 >> 8) & 0xff;
482 	cmd[9]  =  dest2       & 0xff;
483 	cmd[10] = (rotate1 ? 1 : 0) | (rotate2 ? 2 : 0);
484 
485 	return ch_do_scsi(ch, cmd, 12, NULL, 0, REQ_OP_DRV_IN);
486 }
487 
488 static void
489 ch_check_voltag(char *tag)
490 {
491 	int i;
492 
493 	for (i = 0; i < 32; i++) {
494 		/* restrict to ascii */
495 		if (tag[i] >= 0x7f || tag[i] < 0x20)
496 			tag[i] = ' ';
497 		/* don't allow search wildcards */
498 		if (tag[i] == '?' ||
499 		    tag[i] == '*')
500 			tag[i] = ' ';
501 	}
502 }
503 
504 static int
505 ch_set_voltag(scsi_changer *ch, u_int elem,
506 	      int alternate, int clear, u_char *tag)
507 {
508 	u_char  cmd[12];
509 	u_char  *buffer;
510 	int result;
511 
512 	buffer = kzalloc(512, GFP_KERNEL);
513 	if (!buffer)
514 		return -ENOMEM;
515 
516 	DPRINTK("%s %s voltag: 0x%x => \"%s\"\n",
517 		clear     ? "clear"     : "set",
518 		alternate ? "alternate" : "primary",
519 		elem, tag);
520 	memset(cmd,0,sizeof(cmd));
521 	cmd[0]  = SEND_VOLUME_TAG;
522 	cmd[1] = ((ch->device->lun & 0x7) << 5) |
523 		ch_elem_to_typecode(ch,elem);
524 	cmd[2] = (elem >> 8) & 0xff;
525 	cmd[3] = elem        & 0xff;
526 	cmd[5] = clear
527 		? (alternate ? 0x0d : 0x0c)
528 		: (alternate ? 0x0b : 0x0a);
529 
530 	cmd[9] = 255;
531 
532 	memcpy(buffer,tag,32);
533 	ch_check_voltag(buffer);
534 
535 	result = ch_do_scsi(ch, cmd, 12, buffer, 256, REQ_OP_DRV_OUT);
536 	kfree(buffer);
537 	return result;
538 }
539 
540 static int ch_gstatus(scsi_changer *ch, int type, unsigned char __user *dest)
541 {
542 	int retval = 0;
543 	u_char data[16];
544 	unsigned int i;
545 
546 	mutex_lock(&ch->lock);
547 	for (i = 0; i < ch->counts[type]; i++) {
548 		if (0 != ch_read_element_status
549 		    (ch, ch->firsts[type]+i,data)) {
550 			retval = -EIO;
551 			break;
552 		}
553 		put_user(data[2], dest+i);
554 		if (data[2] & CESTATUS_EXCEPT)
555 			VPRINTK(KERN_INFO, "element 0x%x: asc=0x%x, ascq=0x%x\n",
556 				ch->firsts[type]+i,
557 				(int)data[4],(int)data[5]);
558 		retval = ch_read_element_status
559 			(ch, ch->firsts[type]+i,data);
560 		if (0 != retval)
561 			break;
562 	}
563 	mutex_unlock(&ch->lock);
564 	return retval;
565 }
566 
567 /* ------------------------------------------------------------------------ */
568 
569 static void ch_destroy(struct kref *ref)
570 {
571 	scsi_changer *ch = container_of(ref, scsi_changer, ref);
572 
573 	ch->device = NULL;
574 	kfree(ch->dt);
575 	kfree(ch);
576 }
577 
578 static int
579 ch_release(struct inode *inode, struct file *file)
580 {
581 	scsi_changer *ch = file->private_data;
582 
583 	scsi_device_put(ch->device);
584 	file->private_data = NULL;
585 	kref_put(&ch->ref, ch_destroy);
586 	return 0;
587 }
588 
589 static int
590 ch_open(struct inode *inode, struct file *file)
591 {
592 	scsi_changer *ch;
593 	int minor = iminor(inode);
594 
595 	spin_lock(&ch_index_lock);
596 	ch = idr_find(&ch_index_idr, minor);
597 
598 	if (ch == NULL || !kref_get_unless_zero(&ch->ref)) {
599 		spin_unlock(&ch_index_lock);
600 		return -ENXIO;
601 	}
602 	spin_unlock(&ch_index_lock);
603 	if (scsi_device_get(ch->device)) {
604 		kref_put(&ch->ref, ch_destroy);
605 		return -ENXIO;
606 	}
607 	/* Synchronize with ch_probe() */
608 	mutex_lock(&ch->lock);
609 	file->private_data = ch;
610 	mutex_unlock(&ch->lock);
611 	return 0;
612 }
613 
614 static int
615 ch_checkrange(scsi_changer *ch, unsigned int type, unsigned int unit)
616 {
617 	if (type >= CH_TYPES  ||  unit >= ch->counts[type])
618 		return -1;
619 	return 0;
620 }
621 
622 struct changer_element_status32 {
623 	int		ces_type;
624 	compat_uptr_t	ces_data;
625 };
626 #define CHIOGSTATUS32  _IOW('c', 8, struct changer_element_status32)
627 
628 static long ch_ioctl(struct file *file,
629 		    unsigned int cmd, unsigned long arg)
630 {
631 	scsi_changer *ch = file->private_data;
632 	int retval;
633 	void __user *argp = (void __user *)arg;
634 
635 	retval = scsi_ioctl_block_when_processing_errors(ch->device, cmd,
636 			file->f_flags & O_NDELAY);
637 	if (retval)
638 		return retval;
639 
640 	switch (cmd) {
641 	case CHIOGPARAMS:
642 	{
643 		struct changer_params params;
644 
645 		params.cp_curpicker = 0;
646 		params.cp_npickers  = ch->counts[CHET_MT];
647 		params.cp_nslots    = ch->counts[CHET_ST];
648 		params.cp_nportals  = ch->counts[CHET_IE];
649 		params.cp_ndrives   = ch->counts[CHET_DT];
650 
651 		if (copy_to_user(argp, &params, sizeof(params)))
652 			return -EFAULT;
653 		return 0;
654 	}
655 	case CHIOGVPARAMS:
656 	{
657 		struct changer_vendor_params vparams;
658 
659 		memset(&vparams,0,sizeof(vparams));
660 		if (ch->counts[CHET_V1]) {
661 			vparams.cvp_n1  = ch->counts[CHET_V1];
662 			strncpy(vparams.cvp_label1,vendor_labels[0],16);
663 		}
664 		if (ch->counts[CHET_V2]) {
665 			vparams.cvp_n2  = ch->counts[CHET_V2];
666 			strncpy(vparams.cvp_label2,vendor_labels[1],16);
667 		}
668 		if (ch->counts[CHET_V3]) {
669 			vparams.cvp_n3  = ch->counts[CHET_V3];
670 			strncpy(vparams.cvp_label3,vendor_labels[2],16);
671 		}
672 		if (ch->counts[CHET_V4]) {
673 			vparams.cvp_n4  = ch->counts[CHET_V4];
674 			strncpy(vparams.cvp_label4,vendor_labels[3],16);
675 		}
676 		if (copy_to_user(argp, &vparams, sizeof(vparams)))
677 			return -EFAULT;
678 		return 0;
679 	}
680 
681 	case CHIOPOSITION:
682 	{
683 		struct changer_position pos;
684 
685 		if (copy_from_user(&pos, argp, sizeof (pos)))
686 			return -EFAULT;
687 
688 		if (0 != ch_checkrange(ch, pos.cp_type, pos.cp_unit)) {
689 			DPRINTK("CHIOPOSITION: invalid parameter\n");
690 			return -EBADSLT;
691 		}
692 		mutex_lock(&ch->lock);
693 		retval = ch_position(ch,0,
694 				     ch->firsts[pos.cp_type] + pos.cp_unit,
695 				     pos.cp_flags & CP_INVERT);
696 		mutex_unlock(&ch->lock);
697 		return retval;
698 	}
699 
700 	case CHIOMOVE:
701 	{
702 		struct changer_move mv;
703 
704 		if (copy_from_user(&mv, argp, sizeof (mv)))
705 			return -EFAULT;
706 
707 		if (0 != ch_checkrange(ch, mv.cm_fromtype, mv.cm_fromunit) ||
708 		    0 != ch_checkrange(ch, mv.cm_totype,   mv.cm_tounit  )) {
709 			DPRINTK("CHIOMOVE: invalid parameter\n");
710 			return -EBADSLT;
711 		}
712 
713 		mutex_lock(&ch->lock);
714 		retval = ch_move(ch,0,
715 				 ch->firsts[mv.cm_fromtype] + mv.cm_fromunit,
716 				 ch->firsts[mv.cm_totype]   + mv.cm_tounit,
717 				 mv.cm_flags & CM_INVERT);
718 		mutex_unlock(&ch->lock);
719 		return retval;
720 	}
721 
722 	case CHIOEXCHANGE:
723 	{
724 		struct changer_exchange mv;
725 
726 		if (copy_from_user(&mv, argp, sizeof (mv)))
727 			return -EFAULT;
728 
729 		if (0 != ch_checkrange(ch, mv.ce_srctype,  mv.ce_srcunit ) ||
730 		    0 != ch_checkrange(ch, mv.ce_fdsttype, mv.ce_fdstunit) ||
731 		    0 != ch_checkrange(ch, mv.ce_sdsttype, mv.ce_sdstunit)) {
732 			DPRINTK("CHIOEXCHANGE: invalid parameter\n");
733 			return -EBADSLT;
734 		}
735 
736 		mutex_lock(&ch->lock);
737 		retval = ch_exchange
738 			(ch,0,
739 			 ch->firsts[mv.ce_srctype]  + mv.ce_srcunit,
740 			 ch->firsts[mv.ce_fdsttype] + mv.ce_fdstunit,
741 			 ch->firsts[mv.ce_sdsttype] + mv.ce_sdstunit,
742 			 mv.ce_flags & CE_INVERT1, mv.ce_flags & CE_INVERT2);
743 		mutex_unlock(&ch->lock);
744 		return retval;
745 	}
746 
747 	case CHIOGSTATUS:
748 	{
749 		struct changer_element_status ces;
750 
751 		if (copy_from_user(&ces, argp, sizeof (ces)))
752 			return -EFAULT;
753 		if (ces.ces_type < 0 || ces.ces_type >= CH_TYPES)
754 			return -EINVAL;
755 
756 		return ch_gstatus(ch, ces.ces_type, ces.ces_data);
757 	}
758 #ifdef CONFIG_COMPAT
759 	case CHIOGSTATUS32:
760 	{
761 		struct changer_element_status32 ces32;
762 
763 		if (copy_from_user(&ces32, argp, sizeof(ces32)))
764 			return -EFAULT;
765 		if (ces32.ces_type < 0 || ces32.ces_type >= CH_TYPES)
766 			return -EINVAL;
767 
768 		return ch_gstatus(ch, ces32.ces_type,
769 				  compat_ptr(ces32.ces_data));
770 	}
771 #endif
772 	case CHIOGELEM:
773 	{
774 		struct changer_get_element cge;
775 		u_char ch_cmd[12];
776 		u_char *buffer;
777 		unsigned int elem;
778 		int     result,i;
779 
780 		if (copy_from_user(&cge, argp, sizeof (cge)))
781 			return -EFAULT;
782 
783 		if (0 != ch_checkrange(ch, cge.cge_type, cge.cge_unit))
784 			return -EINVAL;
785 		elem = ch->firsts[cge.cge_type] + cge.cge_unit;
786 
787 		buffer = kmalloc(512, GFP_KERNEL);
788 		if (!buffer)
789 			return -ENOMEM;
790 		mutex_lock(&ch->lock);
791 
792 	voltag_retry:
793 		memset(ch_cmd, 0, sizeof(ch_cmd));
794 		ch_cmd[0] = READ_ELEMENT_STATUS;
795 		ch_cmd[1] = ((ch->device->lun & 0x7) << 5) |
796 			(ch->voltags ? 0x10 : 0) |
797 			ch_elem_to_typecode(ch,elem);
798 		ch_cmd[2] = (elem >> 8) & 0xff;
799 		ch_cmd[3] = elem        & 0xff;
800 		ch_cmd[5] = 1;
801 		ch_cmd[9] = 255;
802 
803 		result = ch_do_scsi(ch, ch_cmd, 12, buffer, 256, REQ_OP_DRV_IN);
804 		if (!result) {
805 			cge.cge_status = buffer[18];
806 			cge.cge_flags = 0;
807 			if (buffer[18] & CESTATUS_EXCEPT) {
808 				cge.cge_errno = EIO;
809 			}
810 			if (buffer[25] & 0x80) {
811 				cge.cge_flags |= CGE_SRC;
812 				if (buffer[25] & 0x40)
813 					cge.cge_flags |= CGE_INVERT;
814 				elem = (buffer[26]<<8) | buffer[27];
815 				for (i = 0; i < 4; i++) {
816 					if (elem >= ch->firsts[i] &&
817 					    elem <  ch->firsts[i] + ch->counts[i]) {
818 						cge.cge_srctype = i;
819 						cge.cge_srcunit = elem-ch->firsts[i];
820 					}
821 				}
822 			}
823 			if ((buffer[22] & 0x30) == 0x30) {
824 				cge.cge_flags |= CGE_IDLUN;
825 				cge.cge_id  = buffer[23];
826 				cge.cge_lun = buffer[22] & 7;
827 			}
828 			if (buffer[9] & 0x80) {
829 				cge.cge_flags |= CGE_PVOLTAG;
830 				memcpy(cge.cge_pvoltag,buffer+28,36);
831 			}
832 			if (buffer[9] & 0x40) {
833 				cge.cge_flags |= CGE_AVOLTAG;
834 				memcpy(cge.cge_avoltag,buffer+64,36);
835 			}
836 		} else if (ch->voltags) {
837 			ch->voltags = 0;
838 			VPRINTK(KERN_INFO, "device has no volume tag support\n");
839 			goto voltag_retry;
840 		}
841 		kfree(buffer);
842 		mutex_unlock(&ch->lock);
843 
844 		if (copy_to_user(argp, &cge, sizeof (cge)))
845 			return -EFAULT;
846 		return result;
847 	}
848 
849 	case CHIOINITELEM:
850 	{
851 		mutex_lock(&ch->lock);
852 		retval = ch_init_elem(ch);
853 		mutex_unlock(&ch->lock);
854 		return retval;
855 	}
856 
857 	case CHIOSVOLTAG:
858 	{
859 		struct changer_set_voltag csv;
860 		int elem;
861 
862 		if (copy_from_user(&csv, argp, sizeof(csv)))
863 			return -EFAULT;
864 
865 		if (0 != ch_checkrange(ch, csv.csv_type, csv.csv_unit)) {
866 			DPRINTK("CHIOSVOLTAG: invalid parameter\n");
867 			return -EBADSLT;
868 		}
869 		elem = ch->firsts[csv.csv_type] + csv.csv_unit;
870 		mutex_lock(&ch->lock);
871 		retval = ch_set_voltag(ch, elem,
872 				       csv.csv_flags & CSV_AVOLTAG,
873 				       csv.csv_flags & CSV_CLEARTAG,
874 				       csv.csv_voltag);
875 		mutex_unlock(&ch->lock);
876 		return retval;
877 	}
878 
879 	default:
880 		return scsi_ioctl(ch->device, file->f_mode, cmd, argp);
881 
882 	}
883 }
884 
885 /* ------------------------------------------------------------------------ */
886 
887 static int ch_probe(struct device *dev)
888 {
889 	struct scsi_device *sd = to_scsi_device(dev);
890 	struct device *class_dev;
891 	int ret;
892 	scsi_changer *ch;
893 
894 	if (sd->type != TYPE_MEDIUM_CHANGER)
895 		return -ENODEV;
896 
897 	ch = kzalloc(sizeof(*ch), GFP_KERNEL);
898 	if (NULL == ch)
899 		return -ENOMEM;
900 
901 	idr_preload(GFP_KERNEL);
902 	spin_lock(&ch_index_lock);
903 	ret = idr_alloc(&ch_index_idr, ch, 0, CH_MAX_DEVS + 1, GFP_NOWAIT);
904 	spin_unlock(&ch_index_lock);
905 	idr_preload_end();
906 
907 	if (ret < 0) {
908 		if (ret == -ENOSPC)
909 			ret = -ENODEV;
910 		goto free_ch;
911 	}
912 
913 	ch->minor = ret;
914 	sprintf(ch->name,"ch%d",ch->minor);
915 	ret = scsi_device_get(sd);
916 	if (ret) {
917 		sdev_printk(KERN_WARNING, sd, "ch%d: failed to get device\n",
918 			    ch->minor);
919 		goto remove_idr;
920 	}
921 
922 	mutex_init(&ch->lock);
923 	kref_init(&ch->ref);
924 	ch->device = sd;
925 	class_dev = device_create(ch_sysfs_class, dev,
926 				  MKDEV(SCSI_CHANGER_MAJOR, ch->minor), ch,
927 				  "s%s", ch->name);
928 	if (IS_ERR(class_dev)) {
929 		sdev_printk(KERN_WARNING, sd, "ch%d: device_create failed\n",
930 			    ch->minor);
931 		ret = PTR_ERR(class_dev);
932 		goto put_device;
933 	}
934 
935 	mutex_lock(&ch->lock);
936 	ret = ch_readconfig(ch);
937 	if (ret) {
938 		mutex_unlock(&ch->lock);
939 		goto destroy_dev;
940 	}
941 	if (init)
942 		ch_init_elem(ch);
943 
944 	mutex_unlock(&ch->lock);
945 	dev_set_drvdata(dev, ch);
946 	sdev_printk(KERN_INFO, sd, "Attached scsi changer %s\n", ch->name);
947 
948 	return 0;
949 destroy_dev:
950 	device_destroy(ch_sysfs_class, MKDEV(SCSI_CHANGER_MAJOR, ch->minor));
951 put_device:
952 	scsi_device_put(sd);
953 remove_idr:
954 	idr_remove(&ch_index_idr, ch->minor);
955 free_ch:
956 	kfree(ch);
957 	return ret;
958 }
959 
960 static int ch_remove(struct device *dev)
961 {
962 	scsi_changer *ch = dev_get_drvdata(dev);
963 
964 	spin_lock(&ch_index_lock);
965 	idr_remove(&ch_index_idr, ch->minor);
966 	dev_set_drvdata(dev, NULL);
967 	spin_unlock(&ch_index_lock);
968 
969 	device_destroy(ch_sysfs_class, MKDEV(SCSI_CHANGER_MAJOR,ch->minor));
970 	scsi_device_put(ch->device);
971 	kref_put(&ch->ref, ch_destroy);
972 	return 0;
973 }
974 
975 static struct scsi_driver ch_template = {
976 	.gendrv     	= {
977 		.name	= "ch",
978 		.owner	= THIS_MODULE,
979 		.probe  = ch_probe,
980 		.remove = ch_remove,
981 	},
982 };
983 
984 static const struct file_operations changer_fops = {
985 	.owner		= THIS_MODULE,
986 	.open		= ch_open,
987 	.release	= ch_release,
988 	.unlocked_ioctl	= ch_ioctl,
989 	.compat_ioctl	= compat_ptr_ioctl,
990 	.llseek		= noop_llseek,
991 };
992 
993 static int __init init_ch_module(void)
994 {
995 	int rc;
996 
997 	printk(KERN_INFO "SCSI Media Changer driver v" VERSION " \n");
998         ch_sysfs_class = class_create(THIS_MODULE, "scsi_changer");
999         if (IS_ERR(ch_sysfs_class)) {
1000 		rc = PTR_ERR(ch_sysfs_class);
1001 		return rc;
1002         }
1003 	rc = register_chrdev(SCSI_CHANGER_MAJOR,"ch",&changer_fops);
1004 	if (rc < 0) {
1005 		printk("Unable to get major %d for SCSI-Changer\n",
1006 		       SCSI_CHANGER_MAJOR);
1007 		goto fail1;
1008 	}
1009 	rc = scsi_register_driver(&ch_template.gendrv);
1010 	if (rc < 0)
1011 		goto fail2;
1012 	return 0;
1013 
1014  fail2:
1015 	unregister_chrdev(SCSI_CHANGER_MAJOR, "ch");
1016  fail1:
1017 	class_destroy(ch_sysfs_class);
1018 	return rc;
1019 }
1020 
1021 static void __exit exit_ch_module(void)
1022 {
1023 	scsi_unregister_driver(&ch_template.gendrv);
1024 	unregister_chrdev(SCSI_CHANGER_MAJOR, "ch");
1025 	class_destroy(ch_sysfs_class);
1026 	idr_destroy(&ch_index_idr);
1027 }
1028 
1029 module_init(init_ch_module);
1030 module_exit(exit_ch_module);
1031