1 /*
2  * Changes:
3  * Arnaldo Carvalho de Melo <acme@conectiva.com.br> 08/23/2000
4  * - get rid of some verify_areas and use __copy*user and __get/put_user
5  *   for the ones that remain
6  */
7 #define __NO_VERSION__
8 #include <linux/module.h>
9 
10 #include <asm/io.h>
11 #include <asm/uaccess.h>
12 #include <asm/system.h>
13 #include <asm/page.h>
14 
15 #include <linux/interrupt.h>
16 #include <linux/errno.h>
17 #include <linux/kernel.h>
18 #include <linux/sched.h>
19 #include <linux/mm.h>
20 #include <linux/string.h>
21 
22 #include <linux/blk.h>
23 #include "scsi.h"
24 #include "hosts.h"
25 #include <scsi/scsi_ioctl.h>
26 
27 #define NORMAL_RETRIES			5
28 #define IOCTL_NORMAL_TIMEOUT			(10 * HZ)
29 #define FORMAT_UNIT_TIMEOUT		(2 * 60 * 60 * HZ)
30 #define START_STOP_TIMEOUT		(60 * HZ)
31 #define MOVE_MEDIUM_TIMEOUT		(5 * 60 * HZ)
32 #define READ_ELEMENT_STATUS_TIMEOUT	(5 * 60 * HZ)
33 #define READ_DEFECT_DATA_TIMEOUT	(60 * HZ )  /* ZIP-250 on parallel port takes as long! */
34 
35 #define MAX_BUF PAGE_SIZE
36 
37 /*
38  * If we are told to probe a host, we will return 0 if  the host is not
39  * present, 1 if the host is present, and will return an identifying
40  * string at *arg, if arg is non null, filling to the length stored at
41  * (int *) arg
42  */
43 
ioctl_probe(struct Scsi_Host * host,void * buffer)44 static int ioctl_probe(struct Scsi_Host *host, void *buffer)
45 {
46 	unsigned int len, slen;
47 	const char *string;
48 	int temp = host->hostt->present;
49 
50 	if (temp && buffer) {
51 		if (get_user(len, (unsigned int *) buffer))
52 			return -EFAULT;
53 
54 		if (host->hostt->info)
55 			string = host->hostt->info(host);
56 		else
57 			string = host->hostt->name;
58 		if (string) {
59 			slen = strlen(string);
60 			if (len > slen)
61 				len = slen + 1;
62 			if (copy_to_user(buffer, string, len))
63 				return -EFAULT;
64 		}
65 	}
66 	return temp;
67 }
68 
69 /*
70 
71  * The SCSI_IOCTL_SEND_COMMAND ioctl sends a command out to the SCSI host.
72  * The IOCTL_NORMAL_TIMEOUT and NORMAL_RETRIES  variables are used.
73  *
74  * dev is the SCSI device struct ptr, *(int *) arg is the length of the
75  * input data, if any, not including the command string & counts,
76  * *((int *)arg + 1) is the output buffer size in bytes.
77  *
78  * *(char *) ((int *) arg)[2] the actual command byte.
79  *
80  * Note that if more than MAX_BUF bytes are requested to be transferred,
81  * the ioctl will fail with error EINVAL.  MAX_BUF can be increased in
82  * the future by increasing the size that scsi_malloc will accept.
83  *
84  * This size *does not* include the initial lengths that were passed.
85  *
86  * The SCSI command is read from the memory location immediately after the
87  * length words, and the input data is right after the command.  The SCSI
88  * routines know the command size based on the opcode decode.
89  *
90  * The output area is then filled in starting from the command byte.
91  */
92 
ioctl_internal_command(Scsi_Device * dev,char * cmd,int timeout,int retries)93 static int ioctl_internal_command(Scsi_Device * dev, char *cmd,
94 				  int timeout, int retries)
95 {
96 	int result;
97 	Scsi_Request *SRpnt;
98 	Scsi_Device *SDpnt;
99 
100 
101 	SCSI_LOG_IOCTL(1, printk("Trying ioctl with scsi command %d\n", cmd[0]));
102 	if (NULL == (SRpnt = scsi_allocate_request(dev))) {
103 		printk("SCSI internal ioctl failed, no memory\n");
104 		return -ENOMEM;
105 	}
106 
107 	SRpnt->sr_data_direction = SCSI_DATA_NONE;
108         scsi_wait_req(SRpnt, cmd, NULL, 0, timeout, retries);
109 
110 	SCSI_LOG_IOCTL(2, printk("Ioctl returned  0x%x\n", SRpnt->sr_result));
111 
112 	if (driver_byte(SRpnt->sr_result) != 0)
113 		switch (SRpnt->sr_sense_buffer[2] & 0xf) {
114 		case ILLEGAL_REQUEST:
115 			if (cmd[0] == ALLOW_MEDIUM_REMOVAL)
116 				dev->lockable = 0;
117 			else
118 				printk("SCSI device (ioctl) reports ILLEGAL REQUEST.\n");
119 			break;
120 		case NOT_READY:	/* This happens if there is no disc in drive */
121 			if (dev->removable && (cmd[0] != TEST_UNIT_READY)) {
122 				printk(KERN_INFO "Device not ready.  Make sure there is a disc in the drive.\n");
123 				break;
124 			}
125 		case UNIT_ATTENTION:
126 			if (dev->removable) {
127 				dev->changed = 1;
128 				SRpnt->sr_result = 0;	/* This is no longer considered an error */
129 				/* gag this error, VFS will log it anyway /axboe */
130 				/* printk(KERN_INFO "Disc change detected.\n"); */
131 				break;
132 			};
133 		default:	/* Fall through for non-removable media */
134 			printk("SCSI error: host %d id %d lun %d return code = %x\n",
135 			       dev->host->host_no,
136 			       dev->id,
137 			       dev->lun,
138 			       SRpnt->sr_result);
139 			printk("\tSense class %x, sense error %x, extended sense %x\n",
140 			       sense_class(SRpnt->sr_sense_buffer[0]),
141 			       sense_error(SRpnt->sr_sense_buffer[0]),
142 			       SRpnt->sr_sense_buffer[2] & 0xf);
143 
144 		};
145 
146 	result = SRpnt->sr_result;
147 
148 	SCSI_LOG_IOCTL(2, printk("IOCTL Releasing command\n"));
149 	SDpnt = SRpnt->sr_device;
150 	scsi_release_request(SRpnt);
151 	SRpnt = NULL;
152 
153 	return result;
154 }
155 
156 /*
157  * This interface is depreciated - users should use the scsi generic (sg)
158  * interface instead, as this is a more flexible approach to performing
159  * generic SCSI commands on a device.
160  *
161  * The structure that we are passed should look like:
162  *
163  * struct sdata {
164  *  unsigned int inlen;      [i] Length of data to be written to device
165  *  unsigned int outlen;     [i] Length of data to be read from device
166  *  unsigned char cmd[x];    [i] SCSI command (6 <= x <= 12).
167  *                           [o] Data read from device starts here.
168  *                           [o] On error, sense buffer starts here.
169  *  unsigned char wdata[y];  [i] Data written to device starts here.
170  * };
171  * Notes:
172  *   -  The SCSI command length is determined by examining the 1st byte
173  *      of the given command. There is no way to override this.
174  *   -  Data transfers are limited to PAGE_SIZE (4K on i386, 8K on alpha).
175  *   -  The length (x + y) must be at least OMAX_SB_LEN bytes long to
176  *      accomodate the sense buffer when an error occurs.
177  *      The sense buffer is truncated to OMAX_SB_LEN (16) bytes so that
178  *      old code will not be surprised.
179  *   -  If a Unix error occurs (e.g. ENOMEM) then the user will receive
180  *      a negative return and the Unix error code in 'errno'.
181  *      If the SCSI command succeeds then 0 is returned.
182  *      Positive numbers returned are the compacted SCSI error codes (4
183  *      bytes in one int) where the lowest byte is the SCSI status.
184  *      See the drivers/scsi/scsi.h file for more information on this.
185  *
186  */
187 #define OMAX_SB_LEN 16		/* Old sense buffer length */
188 
scsi_ioctl_send_command(Scsi_Device * dev,Scsi_Ioctl_Command * sic)189 int scsi_ioctl_send_command(Scsi_Device * dev, Scsi_Ioctl_Command * sic)
190 {
191 	char *buf;
192 	unsigned char cmd[MAX_COMMAND_SIZE];
193 	char *cmd_in;
194 	Scsi_Request *SRpnt;
195 	Scsi_Device *SDpnt;
196 	unsigned char opcode;
197 	unsigned int inlen, outlen, cmdlen;
198 	unsigned int needed, buf_needed;
199 	int timeout, retries, result;
200 	int data_direction;
201 
202 	if (!sic)
203 		return -EINVAL;
204 	/*
205 	 * Verify that we can read at least this much.
206 	 */
207 	if (verify_area(VERIFY_READ, sic, sizeof(Scsi_Ioctl_Command)))
208 		return -EFAULT;
209 
210 	if(__get_user(inlen, &sic->inlen))
211 		return -EFAULT;
212 
213 	if(__get_user(outlen, &sic->outlen))
214 		return -EFAULT;
215 
216 	/*
217 	 * We do not transfer more than MAX_BUF with this interface.
218 	 * If the user needs to transfer more data than this, they
219 	 * should use scsi_generics (sg) instead.
220 	 */
221 	if (inlen > MAX_BUF)
222 		return -EINVAL;
223 	if (outlen > MAX_BUF)
224 		return -EINVAL;
225 
226 	cmd_in = sic->data;
227 	if(get_user(opcode, cmd_in))
228 		return -EFAULT;
229 
230 	needed = buf_needed = (inlen > outlen ? inlen : outlen);
231 	if (buf_needed) {
232 		buf_needed = (buf_needed + 511) & ~511;
233 		if (buf_needed > MAX_BUF)
234 			buf_needed = MAX_BUF;
235 		buf = (char *) scsi_malloc(buf_needed);
236 		if (!buf)
237 			return -ENOMEM;
238 		memset(buf, 0, buf_needed);
239 		if( inlen == 0 ) {
240 			data_direction = SCSI_DATA_READ;
241 		} else if (outlen == 0 ) {
242 			data_direction = SCSI_DATA_WRITE;
243 		} else {
244 			/*
245 			 * Can this ever happen?
246 			 */
247 			data_direction = SCSI_DATA_UNKNOWN;
248 		}
249 
250 	} else {
251 		buf = NULL;
252 		data_direction = SCSI_DATA_NONE;
253 	}
254 
255 	/*
256 	 * Obtain the command from the user's address space.
257 	 */
258 	cmdlen = COMMAND_SIZE(opcode);
259 
260 	result = -EFAULT;
261 
262 	if (verify_area(VERIFY_READ, cmd_in, cmdlen + inlen))
263 		goto error;
264 
265 	if(__copy_from_user(cmd, cmd_in, cmdlen))
266 		goto error;
267 
268 	/*
269 	 * Obtain the data to be sent to the device (if any).
270 	 */
271 
272 	if(copy_from_user(buf, cmd_in + cmdlen, inlen))
273 		goto error;
274 
275 	/*
276 	 * Set the lun field to the correct value.
277 	 */
278 	if (dev->scsi_level <= SCSI_2)
279 		cmd[1] = (cmd[1] & 0x1f) | (dev->lun << 5);
280 
281 	switch (opcode) {
282 	case SEND_DIAGNOSTIC:
283 	case FORMAT_UNIT:
284 		timeout = FORMAT_UNIT_TIMEOUT;
285 		retries = 1;
286 		break;
287 	case START_STOP:
288 		timeout = START_STOP_TIMEOUT;
289 		retries = NORMAL_RETRIES;
290 		break;
291 	case MOVE_MEDIUM:
292 		timeout = MOVE_MEDIUM_TIMEOUT;
293 		retries = NORMAL_RETRIES;
294 		break;
295 	case READ_ELEMENT_STATUS:
296 		timeout = READ_ELEMENT_STATUS_TIMEOUT;
297 		retries = NORMAL_RETRIES;
298 		break;
299 	case READ_DEFECT_DATA:
300 		timeout = READ_DEFECT_DATA_TIMEOUT;
301 		retries = 1;
302 		break;
303 	default:
304 		timeout = IOCTL_NORMAL_TIMEOUT;
305 		retries = NORMAL_RETRIES;
306 		break;
307 	}
308 
309 #ifndef DEBUG_NO_CMD
310 
311 
312 	SRpnt = scsi_allocate_request(dev);
313         if( SRpnt == NULL )
314         {
315                 result = -EINTR;
316                 goto error;
317         }
318 
319 	SRpnt->sr_data_direction = data_direction;
320         scsi_wait_req(SRpnt, cmd, buf, needed, timeout, retries);
321 
322 	/*
323 	 * If there was an error condition, pass the info back to the user.
324 	 */
325 
326 	result = SRpnt->sr_result;
327 
328 	if (SRpnt->sr_result) {
329 		int sb_len = sizeof(SRpnt->sr_sense_buffer);
330 
331 		sb_len = (sb_len > OMAX_SB_LEN) ? OMAX_SB_LEN : sb_len;
332 		if (copy_to_user(cmd_in, SRpnt->sr_sense_buffer, sb_len))
333 			result = -EFAULT;
334 	} else {
335 		if (copy_to_user(cmd_in, buf, outlen))
336 			result = -EFAULT;
337 	}
338 
339 	SDpnt = SRpnt->sr_device;
340 	scsi_release_request(SRpnt);
341 	SRpnt = NULL;
342 
343 error:
344 	if (buf)
345 		scsi_free(buf, buf_needed);
346 
347 
348 	return result;
349 #else
350 	{
351 		int i;
352 		printk("scsi_ioctl : device %d.  command = ", dev->id);
353 		for (i = 0; i < cmdlen; ++i)
354 			printk("%02x ", cmd[i]);
355 		printk("\nbuffer =");
356 		for (i = 0; i < 20; ++i)
357 			printk("%02x ", buf[i]);
358 		printk("\n");
359 		printk("inlen = %d, outlen = %d, cmdlen = %d\n",
360 		       inlen, outlen, cmdlen);
361 		printk("buffer = %d, cmd_in = %d\n", buffer, cmd_in);
362 	}
363 	return 0;
364 #endif
365 }
366 
367 /*
368  * The scsi_ioctl_get_pci() function places into arg the value
369  * pci_dev::slot_name (8 characters) for the PCI device (if any).
370  * Returns: 0 on success
371  *          -ENXIO if there isn't a PCI device pointer
372  *                 (could be because the SCSI driver hasn't been
373  *                  updated yet, or because it isn't a SCSI
374  *                  device)
375  *          any copy_to_user() error on failure there
376  */
377 static int
scsi_ioctl_get_pci(Scsi_Device * dev,void * arg)378 scsi_ioctl_get_pci(Scsi_Device * dev, void *arg)
379 {
380 
381         if (!dev->host->pci_dev)
382         	return -ENXIO;
383         if(copy_to_user(arg, dev->host->pci_dev->slot_name,
384                             sizeof(dev->host->pci_dev->slot_name)))
385 		return -EFAULT;
386 	return 0;
387 }
388 
389 
390 /*
391  * the scsi_ioctl() function differs from most ioctls in that it does
392  * not take a major/minor number as the dev field.  Rather, it takes
393  * a pointer to a scsi_devices[] element, a structure.
394  */
scsi_ioctl(Scsi_Device * dev,int cmd,void * arg)395 int scsi_ioctl(Scsi_Device * dev, int cmd, void *arg)
396 {
397 	char scsi_cmd[MAX_COMMAND_SIZE];
398 	char cmd_byte1;
399 
400 	/* No idea how this happens.... */
401 	if (!dev)
402 		return -ENXIO;
403 
404 	/*
405 	 * If we are in the middle of error recovery, don't let anyone
406 	 * else try and use this device.  Also, if error recovery fails, it
407 	 * may try and take the device offline, in which case all further
408 	 * access to the device is prohibited.
409 	 */
410 	if (!scsi_block_when_processing_errors(dev)) {
411 		return -ENODEV;
412 	}
413 	cmd_byte1 = (dev->scsi_level <= SCSI_2) ? (dev->lun << 5) : 0;
414 
415 	switch (cmd) {
416 	case SCSI_IOCTL_GET_IDLUN:
417 		if (verify_area(VERIFY_WRITE, arg, sizeof(Scsi_Idlun)))
418 			return -EFAULT;
419 
420 		__put_user((dev->id & 0xff)
421 			 + ((dev->lun & 0xff) << 8)
422 			 + ((dev->channel & 0xff) << 16)
423 			 + ((dev->host->host_no & 0xff) << 24),
424 			 &((Scsi_Idlun *) arg)->dev_id);
425 		__put_user(dev->host->unique_id, &((Scsi_Idlun *) arg)->host_unique_id);
426 		return 0;
427 	case SCSI_IOCTL_GET_BUS_NUMBER:
428 		return put_user(dev->host->host_no, (int *) arg);
429 	case SCSI_IOCTL_TAGGED_ENABLE:
430 		if (!capable(CAP_SYS_ADMIN))
431 			return -EACCES;
432 		if (!dev->tagged_supported)
433 			return -EINVAL;
434 		dev->tagged_queue = 1;
435 		dev->current_tag = 1;
436 		return 0;
437 	case SCSI_IOCTL_TAGGED_DISABLE:
438 		if (!capable(CAP_SYS_ADMIN))
439 			return -EACCES;
440 		if (!dev->tagged_supported)
441 			return -EINVAL;
442 		dev->tagged_queue = 0;
443 		dev->current_tag = 0;
444 		return 0;
445 	case SCSI_IOCTL_PROBE_HOST:
446 		return ioctl_probe(dev->host, arg);
447 	case SCSI_IOCTL_SEND_COMMAND:
448 		if (!capable(CAP_SYS_ADMIN) || !capable(CAP_SYS_RAWIO))
449 			return -EACCES;
450 		return scsi_ioctl_send_command((Scsi_Device *) dev,
451 					     (Scsi_Ioctl_Command *) arg);
452 	case SCSI_IOCTL_DOORLOCK:
453 		if (!dev->removable || !dev->lockable)
454 			return 0;
455 		scsi_cmd[0] = ALLOW_MEDIUM_REMOVAL;
456 		scsi_cmd[1] = cmd_byte1;
457 		scsi_cmd[2] = scsi_cmd[3] = scsi_cmd[5] = 0;
458 		scsi_cmd[4] = SCSI_REMOVAL_PREVENT;
459 		return ioctl_internal_command((Scsi_Device *) dev, scsi_cmd,
460 				   IOCTL_NORMAL_TIMEOUT, NORMAL_RETRIES);
461 		break;
462 	case SCSI_IOCTL_DOORUNLOCK:
463 		if (!dev->removable || !dev->lockable)
464 			return 0;
465 		scsi_cmd[0] = ALLOW_MEDIUM_REMOVAL;
466 		scsi_cmd[1] = cmd_byte1;
467 		scsi_cmd[2] = scsi_cmd[3] = scsi_cmd[5] = 0;
468 		scsi_cmd[4] = SCSI_REMOVAL_ALLOW;
469 		return ioctl_internal_command((Scsi_Device *) dev, scsi_cmd,
470 				   IOCTL_NORMAL_TIMEOUT, NORMAL_RETRIES);
471 	case SCSI_IOCTL_TEST_UNIT_READY:
472 		scsi_cmd[0] = TEST_UNIT_READY;
473 		scsi_cmd[1] = cmd_byte1;
474 		scsi_cmd[2] = scsi_cmd[3] = scsi_cmd[5] = 0;
475 		scsi_cmd[4] = 0;
476 		return ioctl_internal_command((Scsi_Device *) dev, scsi_cmd,
477 				   IOCTL_NORMAL_TIMEOUT, NORMAL_RETRIES);
478 		break;
479 	case SCSI_IOCTL_START_UNIT:
480 		scsi_cmd[0] = START_STOP;
481 		scsi_cmd[1] = cmd_byte1;
482 		scsi_cmd[2] = scsi_cmd[3] = scsi_cmd[5] = 0;
483 		scsi_cmd[4] = 1;
484 		return ioctl_internal_command((Scsi_Device *) dev, scsi_cmd,
485 				     START_STOP_TIMEOUT, NORMAL_RETRIES);
486 		break;
487 	case SCSI_IOCTL_STOP_UNIT:
488 		scsi_cmd[0] = START_STOP;
489 		scsi_cmd[1] = cmd_byte1;
490 		scsi_cmd[2] = scsi_cmd[3] = scsi_cmd[5] = 0;
491 		scsi_cmd[4] = 0;
492 		return ioctl_internal_command((Scsi_Device *) dev, scsi_cmd,
493 				     START_STOP_TIMEOUT, NORMAL_RETRIES);
494 		break;
495         case SCSI_IOCTL_GET_PCI:
496                 return scsi_ioctl_get_pci(dev, arg);
497                 break;
498 	default:
499 		if (dev->host->hostt->ioctl)
500 			return dev->host->hostt->ioctl(dev, cmd, arg);
501 		return -EINVAL;
502 	}
503 	return -EINVAL;
504 }
505 
506 /*
507  * Just like scsi_ioctl, only callable from kernel space with no
508  * fs segment fiddling.
509  */
510 
kernel_scsi_ioctl(Scsi_Device * dev,int cmd,void * arg)511 int kernel_scsi_ioctl(Scsi_Device * dev, int cmd, void *arg)
512 {
513 	mm_segment_t oldfs;
514 	int tmp;
515 	oldfs = get_fs();
516 	set_fs(get_ds());
517 	tmp = scsi_ioctl(dev, cmd, arg);
518 	set_fs(oldfs);
519 	return tmp;
520 }
521 
522 /*
523  * Overrides for Emacs so that we almost follow Linus's tabbing style.
524  * Emacs will notice this stuff at the end of the file and automatically
525  * adjust the settings for this buffer only.  This must remain at the end
526  * of the file.
527  * ---------------------------------------------------------------------------
528  * Local variables:
529  * c-indent-level: 4
530  * c-brace-imaginary-offset: 0
531  * c-brace-offset: -4
532  * c-argdecl-indent: 4
533  * c-label-offset: -4
534  * c-continued-statement-offset: 4
535  * c-continued-brace-offset: 0
536  * indent-tabs-mode: nil
537  * tab-width: 8
538  * End:
539  */
540