blob: 7a6b530115ac9dbe78e136dc7e7ba5568e015cf0 [file] [log] [blame]
Linus Torvalds1da177e2005-04-16 15:20:36 -07001/*
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#include <linux/module.h>
8#include <linux/blkdev.h>
9#include <linux/interrupt.h>
10#include <linux/errno.h>
11#include <linux/kernel.h>
12#include <linux/sched.h>
13#include <linux/mm.h>
14#include <linux/string.h>
15#include <asm/uaccess.h>
16
17#include <scsi/scsi.h>
18#include <scsi/scsi_device.h>
19#include <scsi/scsi_eh.h>
20#include <scsi/scsi_host.h>
21#include <scsi/scsi_ioctl.h>
22#include <scsi/scsi_request.h>
23#include <scsi/sg.h>
24#include <scsi/scsi_dbg.h>
25
26#include "scsi_logging.h"
27
28#define NORMAL_RETRIES 5
29#define IOCTL_NORMAL_TIMEOUT (10 * HZ)
Linus Torvalds1da177e2005-04-16 15:20:36 -070030
31#define MAX_BUF PAGE_SIZE
32
33/*
34 * If we are told to probe a host, we will return 0 if the host is not
35 * present, 1 if the host is present, and will return an identifying
36 * string at *arg, if arg is non null, filling to the length stored at
37 * (int *) arg
38 */
39
40static int ioctl_probe(struct Scsi_Host *host, void __user *buffer)
41{
42 unsigned int len, slen;
43 const char *string;
44 int temp = host->hostt->present;
45
46 if (temp && buffer) {
47 if (get_user(len, (unsigned int __user *) buffer))
48 return -EFAULT;
49
50 if (host->hostt->info)
51 string = host->hostt->info(host);
52 else
53 string = host->hostt->name;
54 if (string) {
55 slen = strlen(string);
56 if (len > slen)
57 len = slen + 1;
58 if (copy_to_user(buffer, string, len))
59 return -EFAULT;
60 }
61 }
62 return temp;
63}
64
65/*
66
67 * The SCSI_IOCTL_SEND_COMMAND ioctl sends a command out to the SCSI host.
68 * The IOCTL_NORMAL_TIMEOUT and NORMAL_RETRIES variables are used.
69 *
70 * dev is the SCSI device struct ptr, *(int *) arg is the length of the
71 * input data, if any, not including the command string & counts,
72 * *((int *)arg + 1) is the output buffer size in bytes.
73 *
74 * *(char *) ((int *) arg)[2] the actual command byte.
75 *
76 * Note that if more than MAX_BUF bytes are requested to be transferred,
77 * the ioctl will fail with error EINVAL.
78 *
79 * This size *does not* include the initial lengths that were passed.
80 *
81 * The SCSI command is read from the memory location immediately after the
82 * length words, and the input data is right after the command. The SCSI
83 * routines know the command size based on the opcode decode.
84 *
85 * The output area is then filled in starting from the command byte.
86 */
87
88static int ioctl_internal_command(struct scsi_device *sdev, char *cmd,
89 int timeout, int retries)
90{
91 struct scsi_request *sreq;
92 int result;
93 struct scsi_sense_hdr sshdr;
94
95 SCSI_LOG_IOCTL(1, printk("Trying ioctl with scsi command %d\n", *cmd));
96
97 sreq = scsi_allocate_request(sdev, GFP_KERNEL);
98 if (!sreq) {
99 printk(KERN_WARNING "SCSI internal ioctl failed, no memory\n");
100 return -ENOMEM;
101 }
102
103 sreq->sr_data_direction = DMA_NONE;
104 scsi_wait_req(sreq, cmd, NULL, 0, timeout, retries);
105
106 SCSI_LOG_IOCTL(2, printk("Ioctl returned 0x%x\n", sreq->sr_result));
107
108 if ((driver_byte(sreq->sr_result) & DRIVER_SENSE) &&
109 (scsi_request_normalize_sense(sreq, &sshdr))) {
110 switch (sshdr.sense_key) {
111 case ILLEGAL_REQUEST:
112 if (cmd[0] == ALLOW_MEDIUM_REMOVAL)
113 sdev->lockable = 0;
114 else
115 printk(KERN_INFO "ioctl_internal_command: "
116 "ILLEGAL REQUEST asc=0x%x ascq=0x%x\n",
117 sshdr.asc, sshdr.ascq);
118 break;
119 case NOT_READY: /* This happens if there is no disc in drive */
120 if (sdev->removable && (cmd[0] != TEST_UNIT_READY)) {
121 printk(KERN_INFO "Device not ready. Make sure"
122 " there is a disc in the drive.\n");
123 break;
124 }
125 case UNIT_ATTENTION:
126 if (sdev->removable) {
127 sdev->changed = 1;
128 sreq->sr_result = 0; /* This is no longer considered an error */
129 break;
130 }
131 default: /* Fall through for non-removable media */
132 printk(KERN_INFO "ioctl_internal_command: <%d %d %d "
133 "%d> return code = %x\n",
134 sdev->host->host_no,
135 sdev->channel,
136 sdev->id,
137 sdev->lun,
138 sreq->sr_result);
139 scsi_print_req_sense(" ", sreq);
140 break;
141 }
142 }
143
144 result = sreq->sr_result;
145 SCSI_LOG_IOCTL(2, printk("IOCTL Releasing command\n"));
146 scsi_release_request(sreq);
147 return result;
148}
149
150int scsi_set_medium_removal(struct scsi_device *sdev, char state)
151{
152 char scsi_cmd[MAX_COMMAND_SIZE];
153 int ret;
154
155 if (!sdev->removable || !sdev->lockable)
156 return 0;
157
158 scsi_cmd[0] = ALLOW_MEDIUM_REMOVAL;
159 scsi_cmd[1] = 0;
160 scsi_cmd[2] = 0;
161 scsi_cmd[3] = 0;
162 scsi_cmd[4] = state;
163 scsi_cmd[5] = 0;
164
165 ret = ioctl_internal_command(sdev, scsi_cmd,
166 IOCTL_NORMAL_TIMEOUT, NORMAL_RETRIES);
167 if (ret == 0)
168 sdev->locked = (state == SCSI_REMOVAL_PREVENT);
169 return ret;
170}
171EXPORT_SYMBOL(scsi_set_medium_removal);
172
173/*
174 * This interface is deprecated - users should use the scsi generic (sg)
175 * interface instead, as this is a more flexible approach to performing
176 * generic SCSI commands on a device.
177 *
178 * The structure that we are passed should look like:
179 *
180 * struct sdata {
181 * unsigned int inlen; [i] Length of data to be written to device
182 * unsigned int outlen; [i] Length of data to be read from device
183 * unsigned char cmd[x]; [i] SCSI command (6 <= x <= 12).
184 * [o] Data read from device starts here.
185 * [o] On error, sense buffer starts here.
186 * unsigned char wdata[y]; [i] Data written to device starts here.
187 * };
188 * Notes:
189 * - The SCSI command length is determined by examining the 1st byte
190 * of the given command. There is no way to override this.
191 * - Data transfers are limited to PAGE_SIZE (4K on i386, 8K on alpha).
192 * - The length (x + y) must be at least OMAX_SB_LEN bytes long to
193 * accommodate the sense buffer when an error occurs.
194 * The sense buffer is truncated to OMAX_SB_LEN (16) bytes so that
195 * old code will not be surprised.
196 * - If a Unix error occurs (e.g. ENOMEM) then the user will receive
197 * a negative return and the Unix error code in 'errno'.
198 * If the SCSI command succeeds then 0 is returned.
199 * Positive numbers returned are the compacted SCSI error codes (4
200 * bytes in one int) where the lowest byte is the SCSI status.
201 * See the drivers/scsi/scsi.h file for more information on this.
202 *
203 */
204#define OMAX_SB_LEN 16 /* Old sense buffer length */
205
206int scsi_ioctl_send_command(struct scsi_device *sdev,
207 struct scsi_ioctl_command __user *sic)
208{
209 char *buf;
210 unsigned char cmd[MAX_COMMAND_SIZE];
211 char __user *cmd_in;
212 struct scsi_request *sreq;
213 unsigned char opcode;
214 unsigned int inlen, outlen, cmdlen;
215 unsigned int needed, buf_needed;
216 int timeout, retries, result;
217 int data_direction, gfp_mask = GFP_KERNEL;
218
219 if (!sic)
220 return -EINVAL;
221
222 if (sdev->host->unchecked_isa_dma)
223 gfp_mask |= GFP_DMA;
224
225 /*
226 * Verify that we can read at least this much.
227 */
228 if (!access_ok(VERIFY_READ, sic, sizeof(Scsi_Ioctl_Command)))
229 return -EFAULT;
230
231 if(__get_user(inlen, &sic->inlen))
232 return -EFAULT;
233
234 if(__get_user(outlen, &sic->outlen))
235 return -EFAULT;
236
237 /*
238 * We do not transfer more than MAX_BUF with this interface.
239 * If the user needs to transfer more data than this, they
240 * should use scsi_generics (sg) instead.
241 */
242 if (inlen > MAX_BUF)
243 return -EINVAL;
244 if (outlen > MAX_BUF)
245 return -EINVAL;
246
247 cmd_in = sic->data;
248 if(get_user(opcode, cmd_in))
249 return -EFAULT;
250
251 needed = buf_needed = (inlen > outlen ? inlen : outlen);
252 if (buf_needed) {
253 buf_needed = (buf_needed + 511) & ~511;
254 if (buf_needed > MAX_BUF)
255 buf_needed = MAX_BUF;
256 buf = kmalloc(buf_needed, gfp_mask);
257 if (!buf)
258 return -ENOMEM;
259 memset(buf, 0, buf_needed);
260 if (inlen == 0) {
261 data_direction = DMA_FROM_DEVICE;
262 } else if (outlen == 0 ) {
263 data_direction = DMA_TO_DEVICE;
264 } else {
265 /*
266 * Can this ever happen?
267 */
268 data_direction = DMA_BIDIRECTIONAL;
269 }
270
271 } else {
272 buf = NULL;
273 data_direction = DMA_NONE;
274 }
275
276 /*
277 * Obtain the command from the user's address space.
278 */
279 cmdlen = COMMAND_SIZE(opcode);
280
281 result = -EFAULT;
282
283 if (!access_ok(VERIFY_READ, cmd_in, cmdlen + inlen))
284 goto error;
285
286 if(__copy_from_user(cmd, cmd_in, cmdlen))
287 goto error;
288
289 /*
290 * Obtain the data to be sent to the device (if any).
291 */
292
293 if(copy_from_user(buf, cmd_in + cmdlen, inlen))
294 goto error;
295
296 switch (opcode) {
297 case SEND_DIAGNOSTIC:
298 case FORMAT_UNIT:
299 timeout = FORMAT_UNIT_TIMEOUT;
300 retries = 1;
301 break;
302 case START_STOP:
303 timeout = START_STOP_TIMEOUT;
304 retries = NORMAL_RETRIES;
305 break;
306 case MOVE_MEDIUM:
307 timeout = MOVE_MEDIUM_TIMEOUT;
308 retries = NORMAL_RETRIES;
309 break;
310 case READ_ELEMENT_STATUS:
311 timeout = READ_ELEMENT_STATUS_TIMEOUT;
312 retries = NORMAL_RETRIES;
313 break;
314 case READ_DEFECT_DATA:
315 timeout = READ_DEFECT_DATA_TIMEOUT;
316 retries = 1;
317 break;
318 default:
319 timeout = IOCTL_NORMAL_TIMEOUT;
320 retries = NORMAL_RETRIES;
321 break;
322 }
323
324 sreq = scsi_allocate_request(sdev, GFP_KERNEL);
325 if (!sreq) {
326 result = -EINTR;
327 goto error;
328 }
329
330 sreq->sr_data_direction = data_direction;
331 scsi_wait_req(sreq, cmd, buf, needed, timeout, retries);
332
333 /*
334 * If there was an error condition, pass the info back to the user.
335 */
336 result = sreq->sr_result;
337 if (result) {
338 int sb_len = sizeof(sreq->sr_sense_buffer);
339
340 sb_len = (sb_len > OMAX_SB_LEN) ? OMAX_SB_LEN : sb_len;
341 if (copy_to_user(cmd_in, sreq->sr_sense_buffer, sb_len))
342 result = -EFAULT;
343 } else {
344 if (copy_to_user(cmd_in, buf, outlen))
345 result = -EFAULT;
346 }
347
348 scsi_release_request(sreq);
349error:
350 kfree(buf);
351 return result;
352}
353EXPORT_SYMBOL(scsi_ioctl_send_command);
354
355/*
356 * The scsi_ioctl_get_pci() function places into arg the value
357 * pci_dev::slot_name (8 characters) for the PCI device (if any).
358 * Returns: 0 on success
359 * -ENXIO if there isn't a PCI device pointer
360 * (could be because the SCSI driver hasn't been
361 * updated yet, or because it isn't a SCSI
362 * device)
363 * any copy_to_user() error on failure there
364 */
365static int scsi_ioctl_get_pci(struct scsi_device *sdev, void __user *arg)
366{
367 struct device *dev = scsi_get_device(sdev->host);
368
369 if (!dev)
370 return -ENXIO;
371 return copy_to_user(arg, dev->bus_id, sizeof(dev->bus_id))? -EFAULT: 0;
372}
373
374
375/*
376 * the scsi_ioctl() function differs from most ioctls in that it does
377 * not take a major/minor number as the dev field. Rather, it takes
378 * a pointer to a scsi_devices[] element, a structure.
379 */
380int scsi_ioctl(struct scsi_device *sdev, int cmd, void __user *arg)
381{
382 char scsi_cmd[MAX_COMMAND_SIZE];
383
384 /* No idea how this happens.... */
385 if (!sdev)
386 return -ENXIO;
387
388 /*
389 * If we are in the middle of error recovery, don't let anyone
390 * else try and use this device. Also, if error recovery fails, it
391 * may try and take the device offline, in which case all further
392 * access to the device is prohibited.
393 */
394 if (!scsi_block_when_processing_errors(sdev))
395 return -ENODEV;
396
397 /* Check for deprecated ioctls ... all the ioctls which don't
398 * follow the new unique numbering scheme are deprecated */
399 switch (cmd) {
400 case SCSI_IOCTL_SEND_COMMAND:
401 case SCSI_IOCTL_TEST_UNIT_READY:
402 case SCSI_IOCTL_BENCHMARK_COMMAND:
403 case SCSI_IOCTL_SYNC:
404 case SCSI_IOCTL_START_UNIT:
405 case SCSI_IOCTL_STOP_UNIT:
406 printk(KERN_WARNING "program %s is using a deprecated SCSI "
407 "ioctl, please convert it to SG_IO\n", current->comm);
408 break;
409 default:
410 break;
411 }
412
413 switch (cmd) {
414 case SCSI_IOCTL_GET_IDLUN:
415 if (!access_ok(VERIFY_WRITE, arg, sizeof(struct scsi_idlun)))
416 return -EFAULT;
417
418 __put_user((sdev->id & 0xff)
419 + ((sdev->lun & 0xff) << 8)
420 + ((sdev->channel & 0xff) << 16)
421 + ((sdev->host->host_no & 0xff) << 24),
422 &((struct scsi_idlun __user *)arg)->dev_id);
423 __put_user(sdev->host->unique_id,
424 &((struct scsi_idlun __user *)arg)->host_unique_id);
425 return 0;
426 case SCSI_IOCTL_GET_BUS_NUMBER:
427 return put_user(sdev->host->host_no, (int __user *)arg);
428 case SCSI_IOCTL_PROBE_HOST:
429 return ioctl_probe(sdev->host, arg);
430 case SCSI_IOCTL_SEND_COMMAND:
431 if (!capable(CAP_SYS_ADMIN) || !capable(CAP_SYS_RAWIO))
432 return -EACCES;
433 return scsi_ioctl_send_command(sdev, arg);
434 case SCSI_IOCTL_DOORLOCK:
435 return scsi_set_medium_removal(sdev, SCSI_REMOVAL_PREVENT);
436 case SCSI_IOCTL_DOORUNLOCK:
437 return scsi_set_medium_removal(sdev, SCSI_REMOVAL_ALLOW);
438 case SCSI_IOCTL_TEST_UNIT_READY:
439 return scsi_test_unit_ready(sdev, IOCTL_NORMAL_TIMEOUT,
440 NORMAL_RETRIES);
441 case SCSI_IOCTL_START_UNIT:
442 scsi_cmd[0] = START_STOP;
443 scsi_cmd[1] = 0;
444 scsi_cmd[2] = scsi_cmd[3] = scsi_cmd[5] = 0;
445 scsi_cmd[4] = 1;
446 return ioctl_internal_command(sdev, scsi_cmd,
447 START_STOP_TIMEOUT, NORMAL_RETRIES);
448 case SCSI_IOCTL_STOP_UNIT:
449 scsi_cmd[0] = START_STOP;
450 scsi_cmd[1] = 0;
451 scsi_cmd[2] = scsi_cmd[3] = scsi_cmd[5] = 0;
452 scsi_cmd[4] = 0;
453 return ioctl_internal_command(sdev, scsi_cmd,
454 START_STOP_TIMEOUT, NORMAL_RETRIES);
455 case SCSI_IOCTL_GET_PCI:
456 return scsi_ioctl_get_pci(sdev, arg);
457 default:
458 if (sdev->host->hostt->ioctl)
459 return sdev->host->hostt->ioctl(sdev, cmd, arg);
460 }
461 return -EINVAL;
462}
463EXPORT_SYMBOL(scsi_ioctl);
464
465/*
466 * the scsi_nonblock_ioctl() function is designed for ioctls which may
467 * be executed even if the device is in recovery.
468 */
469int scsi_nonblockable_ioctl(struct scsi_device *sdev, int cmd,
470 void __user *arg, struct file *filp)
471{
472 int val, result;
473
474 /* The first set of iocts may be executed even if we're doing
475 * error processing, as long as the device was opened
476 * non-blocking */
477 if (filp && filp->f_flags & O_NONBLOCK) {
478 if (test_bit(SHOST_RECOVERY,
479 &sdev->host->shost_state))
480 return -ENODEV;
481 } else if (!scsi_block_when_processing_errors(sdev))
482 return -ENODEV;
483
484 switch (cmd) {
485 case SG_SCSI_RESET:
486 result = get_user(val, (int __user *)arg);
487 if (result)
488 return result;
489 if (val == SG_SCSI_RESET_NOTHING)
490 return 0;
491 switch (val) {
492 case SG_SCSI_RESET_DEVICE:
493 val = SCSI_TRY_RESET_DEVICE;
494 break;
495 case SG_SCSI_RESET_BUS:
496 val = SCSI_TRY_RESET_BUS;
497 break;
498 case SG_SCSI_RESET_HOST:
499 val = SCSI_TRY_RESET_HOST;
500 break;
501 default:
502 return -EINVAL;
503 }
504 if (!capable(CAP_SYS_ADMIN) || !capable(CAP_SYS_RAWIO))
505 return -EACCES;
506 return (scsi_reset_provider(sdev, val) ==
507 SUCCESS) ? 0 : -EIO;
508 }
509 return -ENODEV;
510}
511EXPORT_SYMBOL(scsi_nonblockable_ioctl);