xref: /linux/drivers/s390/block/dasd_ioctl.c (revision a02001086bbfb4da35d1228bebc2f1b442db455f) 
1 /*
2  * Author(s)......: Holger Smolinski <Holger.Smolinski@de.ibm.com>
3  *		    Horst Hummel <Horst.Hummel@de.ibm.com>
4  *		    Carsten Otte <Cotte@de.ibm.com>
5  *		    Martin Schwidefsky <schwidefsky@de.ibm.com>
6  * Bugreports.to..: <Linux390@de.ibm.com>
7  * Copyright IBM Corp. 1999, 2001
8  *
9  * i/o controls for the dasd driver.
10  */
11 
12 #define KMSG_COMPONENT "dasd"
13 
14 #include <linux/interrupt.h>
15 #include <linux/compat.h>
16 #include <linux/major.h>
17 #include <linux/fs.h>
18 #include <linux/blkpg.h>
19 #include <linux/slab.h>
20 #include <asm/compat.h>
21 #include <asm/ccwdev.h>
22 #include <asm/schid.h>
23 #include <asm/cmb.h>
24 #include <asm/uaccess.h>
25 
26 /* This is ugly... */
27 #define PRINTK_HEADER "dasd_ioctl:"
28 
29 #include "dasd_int.h"
30 
31 
32 static int
33 dasd_ioctl_api_version(void __user *argp)
34 {
35 	int ver = DASD_API_VERSION;
36 	return put_user(ver, (int __user *)argp);
37 }
38 
39 /*
40  * Enable device.
41  * used by dasdfmt after BIODASDDISABLE to retrigger blocksize detection
42  */
43 static int
44 dasd_ioctl_enable(struct block_device *bdev)
45 {
46 	struct dasd_device *base;
47 
48 	if (!capable(CAP_SYS_ADMIN))
49 		return -EACCES;
50 
51 	base = dasd_device_from_gendisk(bdev->bd_disk);
52 	if (!base)
53 		return -ENODEV;
54 
55 	dasd_enable_device(base);
56 	/* Formatting the dasd device can change the capacity. */
57 	mutex_lock(&bdev->bd_mutex);
58 	i_size_write(bdev->bd_inode,
59 		     (loff_t)get_capacity(base->block->gdp) << 9);
60 	mutex_unlock(&bdev->bd_mutex);
61 	dasd_put_device(base);
62 	return 0;
63 }
64 
65 /*
66  * Disable device.
67  * Used by dasdfmt. Disable I/O operations but allow ioctls.
68  */
69 static int
70 dasd_ioctl_disable(struct block_device *bdev)
71 {
72 	struct dasd_device *base;
73 
74 	if (!capable(CAP_SYS_ADMIN))
75 		return -EACCES;
76 
77 	base = dasd_device_from_gendisk(bdev->bd_disk);
78 	if (!base)
79 		return -ENODEV;
80 	/*
81 	 * Man this is sick. We don't do a real disable but only downgrade
82 	 * the device to DASD_STATE_BASIC. The reason is that dasdfmt uses
83 	 * BIODASDDISABLE to disable accesses to the device via the block
84 	 * device layer but it still wants to do i/o on the device by
85 	 * using the BIODASDFMT ioctl. Therefore the correct state for the
86 	 * device is DASD_STATE_BASIC that allows to do basic i/o.
87 	 */
88 	dasd_set_target_state(base, DASD_STATE_BASIC);
89 	/*
90 	 * Set i_size to zero, since read, write, etc. check against this
91 	 * value.
92 	 */
93 	mutex_lock(&bdev->bd_mutex);
94 	i_size_write(bdev->bd_inode, 0);
95 	mutex_unlock(&bdev->bd_mutex);
96 	dasd_put_device(base);
97 	return 0;
98 }
99 
100 /*
101  * Quiesce device.
102  */
103 static int dasd_ioctl_quiesce(struct dasd_block *block)
104 {
105 	unsigned long flags;
106 	struct dasd_device *base;
107 
108 	base = block->base;
109 	if (!capable (CAP_SYS_ADMIN))
110 		return -EACCES;
111 
112 	pr_info("%s: The DASD has been put in the quiesce "
113 		"state\n", dev_name(&base->cdev->dev));
114 	spin_lock_irqsave(get_ccwdev_lock(base->cdev), flags);
115 	dasd_device_set_stop_bits(base, DASD_STOPPED_QUIESCE);
116 	spin_unlock_irqrestore(get_ccwdev_lock(base->cdev), flags);
117 	return 0;
118 }
119 
120 
121 /*
122  * Resume device.
123  */
124 static int dasd_ioctl_resume(struct dasd_block *block)
125 {
126 	unsigned long flags;
127 	struct dasd_device *base;
128 
129 	base = block->base;
130 	if (!capable (CAP_SYS_ADMIN))
131 		return -EACCES;
132 
133 	pr_info("%s: I/O operations have been resumed "
134 		"on the DASD\n", dev_name(&base->cdev->dev));
135 	spin_lock_irqsave(get_ccwdev_lock(base->cdev), flags);
136 	dasd_device_remove_stop_bits(base, DASD_STOPPED_QUIESCE);
137 	spin_unlock_irqrestore(get_ccwdev_lock(base->cdev), flags);
138 
139 	dasd_schedule_block_bh(block);
140 	return 0;
141 }
142 
143 /*
144  * Abort all failfast I/O on a device.
145  */
146 static int dasd_ioctl_abortio(struct dasd_block *block)
147 {
148 	unsigned long flags;
149 	struct dasd_device *base;
150 	struct dasd_ccw_req *cqr, *n;
151 
152 	base = block->base;
153 	if (!capable(CAP_SYS_ADMIN))
154 		return -EACCES;
155 
156 	if (test_and_set_bit(DASD_FLAG_ABORTALL, &base->flags))
157 		return 0;
158 	DBF_DEV_EVENT(DBF_NOTICE, base, "%s", "abortall flag set");
159 
160 	spin_lock_irqsave(&block->request_queue_lock, flags);
161 	spin_lock(&block->queue_lock);
162 	list_for_each_entry_safe(cqr, n, &block->ccw_queue, blocklist) {
163 		if (test_bit(DASD_CQR_FLAGS_FAILFAST, &cqr->flags) &&
164 		    cqr->callback_data &&
165 		    cqr->callback_data != DASD_SLEEPON_START_TAG &&
166 		    cqr->callback_data != DASD_SLEEPON_END_TAG) {
167 			spin_unlock(&block->queue_lock);
168 			blk_abort_request(cqr->callback_data);
169 			spin_lock(&block->queue_lock);
170 		}
171 	}
172 	spin_unlock(&block->queue_lock);
173 	spin_unlock_irqrestore(&block->request_queue_lock, flags);
174 
175 	dasd_schedule_block_bh(block);
176 	return 0;
177 }
178 
179 /*
180  * Allow I/O on a device
181  */
182 static int dasd_ioctl_allowio(struct dasd_block *block)
183 {
184 	struct dasd_device *base;
185 
186 	base = block->base;
187 	if (!capable(CAP_SYS_ADMIN))
188 		return -EACCES;
189 
190 	if (test_and_clear_bit(DASD_FLAG_ABORTALL, &base->flags))
191 		DBF_DEV_EVENT(DBF_NOTICE, base, "%s", "abortall flag unset");
192 
193 	return 0;
194 }
195 
196 /*
197  * performs formatting of _device_ according to _fdata_
198  * Note: The discipline's format_function is assumed to deliver formatting
199  * commands to format multiple units of the device. In terms of the ECKD
200  * devices this means CCWs are generated to format multiple tracks.
201  */
202 static int
203 dasd_format(struct dasd_block *block, struct format_data_t *fdata)
204 {
205 	struct dasd_device *base;
206 	int enable_pav = 1;
207 	int rc, retries;
208 	int start, stop;
209 
210 	base = block->base;
211 	if (base->discipline->format_device == NULL)
212 		return -EPERM;
213 
214 	if (base->state != DASD_STATE_BASIC) {
215 		pr_warn("%s: The DASD cannot be formatted while it is enabled\n",
216 			dev_name(&base->cdev->dev));
217 		return -EBUSY;
218 	}
219 
220 	DBF_DEV_EVENT(DBF_NOTICE, base,
221 		      "formatting units %u to %u (%u B blocks) flags %u",
222 		      fdata->start_unit,
223 		      fdata->stop_unit, fdata->blksize, fdata->intensity);
224 
225 	/* Since dasdfmt keeps the device open after it was disabled,
226 	 * there still exists an inode for this device.
227 	 * We must update i_blkbits, otherwise we might get errors when
228 	 * enabling the device later.
229 	 */
230 	if (fdata->start_unit == 0) {
231 		struct block_device *bdev = bdget_disk(block->gdp, 0);
232 		bdev->bd_inode->i_blkbits = blksize_bits(fdata->blksize);
233 		bdput(bdev);
234 	}
235 
236 	retries = 255;
237 	/* backup start- and endtrack for retries */
238 	start = fdata->start_unit;
239 	stop = fdata->stop_unit;
240 	do {
241 		rc = base->discipline->format_device(base, fdata, enable_pav);
242 		if (rc) {
243 			if (rc == -EAGAIN) {
244 				retries--;
245 				/* disable PAV in case of errors */
246 				enable_pav = 0;
247 				fdata->start_unit = start;
248 				fdata->stop_unit = stop;
249 			} else
250 				return rc;
251 		} else
252 			/* success */
253 			break;
254 	} while (retries);
255 
256 	if (!retries)
257 		return -EIO;
258 	else
259 		return 0;
260 }
261 
262 /*
263  * Format device.
264  */
265 static int
266 dasd_ioctl_format(struct block_device *bdev, void __user *argp)
267 {
268 	struct dasd_device *base;
269 	struct format_data_t fdata;
270 	int rc;
271 
272 	if (!capable(CAP_SYS_ADMIN))
273 		return -EACCES;
274 	if (!argp)
275 		return -EINVAL;
276 	base = dasd_device_from_gendisk(bdev->bd_disk);
277 	if (!base)
278 		return -ENODEV;
279 	if (base->features & DASD_FEATURE_READONLY ||
280 	    test_bit(DASD_FLAG_DEVICE_RO, &base->flags)) {
281 		dasd_put_device(base);
282 		return -EROFS;
283 	}
284 	if (copy_from_user(&fdata, argp, sizeof(struct format_data_t))) {
285 		dasd_put_device(base);
286 		return -EFAULT;
287 	}
288 	if (bdev != bdev->bd_contains) {
289 		pr_warning("%s: The specified DASD is a partition and cannot "
290 			   "be formatted\n",
291 			   dev_name(&base->cdev->dev));
292 		dasd_put_device(base);
293 		return -EINVAL;
294 	}
295 	rc = dasd_format(base->block, &fdata);
296 	dasd_put_device(base);
297 	return rc;
298 }
299 
300 #ifdef CONFIG_DASD_PROFILE
301 /*
302  * Reset device profile information
303  */
304 static int dasd_ioctl_reset_profile(struct dasd_block *block)
305 {
306 	dasd_profile_reset(&block->profile);
307 	return 0;
308 }
309 
310 /*
311  * Return device profile information
312  */
313 static int dasd_ioctl_read_profile(struct dasd_block *block, void __user *argp)
314 {
315 	struct dasd_profile_info_t *data;
316 	int rc = 0;
317 
318 	data = kmalloc(sizeof(*data), GFP_KERNEL);
319 	if (!data)
320 		return -ENOMEM;
321 
322 	spin_lock_bh(&block->profile.lock);
323 	if (block->profile.data) {
324 		data->dasd_io_reqs = block->profile.data->dasd_io_reqs;
325 		data->dasd_io_sects = block->profile.data->dasd_io_sects;
326 		memcpy(data->dasd_io_secs, block->profile.data->dasd_io_secs,
327 		       sizeof(data->dasd_io_secs));
328 		memcpy(data->dasd_io_times, block->profile.data->dasd_io_times,
329 		       sizeof(data->dasd_io_times));
330 		memcpy(data->dasd_io_timps, block->profile.data->dasd_io_timps,
331 		       sizeof(data->dasd_io_timps));
332 		memcpy(data->dasd_io_time1, block->profile.data->dasd_io_time1,
333 		       sizeof(data->dasd_io_time1));
334 		memcpy(data->dasd_io_time2, block->profile.data->dasd_io_time2,
335 		       sizeof(data->dasd_io_time2));
336 		memcpy(data->dasd_io_time2ps,
337 		       block->profile.data->dasd_io_time2ps,
338 		       sizeof(data->dasd_io_time2ps));
339 		memcpy(data->dasd_io_time3, block->profile.data->dasd_io_time3,
340 		       sizeof(data->dasd_io_time3));
341 		memcpy(data->dasd_io_nr_req,
342 		       block->profile.data->dasd_io_nr_req,
343 		       sizeof(data->dasd_io_nr_req));
344 		spin_unlock_bh(&block->profile.lock);
345 	} else {
346 		spin_unlock_bh(&block->profile.lock);
347 		rc = -EIO;
348 		goto out;
349 	}
350 	if (copy_to_user(argp, data, sizeof(*data)))
351 		rc = -EFAULT;
352 out:
353 	kfree(data);
354 	return rc;
355 }
356 #else
357 static int dasd_ioctl_reset_profile(struct dasd_block *block)
358 {
359 	return -ENOTTY;
360 }
361 
362 static int dasd_ioctl_read_profile(struct dasd_block *block, void __user *argp)
363 {
364 	return -ENOTTY;
365 }
366 #endif
367 
368 /*
369  * Return dasd information. Used for BIODASDINFO and BIODASDINFO2.
370  */
371 static int dasd_ioctl_information(struct dasd_block *block,
372 				  unsigned int cmd, void __user *argp)
373 {
374 	struct dasd_information2_t *dasd_info;
375 	struct subchannel_id sch_id;
376 	struct ccw_dev_id dev_id;
377 	struct dasd_device *base;
378 	struct ccw_device *cdev;
379 	unsigned long flags;
380 	int rc;
381 
382 	base = block->base;
383 	if (!base->discipline || !base->discipline->fill_info)
384 		return -EINVAL;
385 
386 	dasd_info = kzalloc(sizeof(struct dasd_information2_t), GFP_KERNEL);
387 	if (dasd_info == NULL)
388 		return -ENOMEM;
389 
390 	rc = base->discipline->fill_info(base, dasd_info);
391 	if (rc) {
392 		kfree(dasd_info);
393 		return rc;
394 	}
395 
396 	cdev = base->cdev;
397 	ccw_device_get_id(cdev, &dev_id);
398 	ccw_device_get_schid(cdev, &sch_id);
399 
400 	dasd_info->devno = dev_id.devno;
401 	dasd_info->schid = sch_id.sch_no;
402 	dasd_info->cu_type = cdev->id.cu_type;
403 	dasd_info->cu_model = cdev->id.cu_model;
404 	dasd_info->dev_type = cdev->id.dev_type;
405 	dasd_info->dev_model = cdev->id.dev_model;
406 	dasd_info->status = base->state;
407 	/*
408 	 * The open_count is increased for every opener, that includes
409 	 * the blkdev_get in dasd_scan_partitions.
410 	 * This must be hidden from user-space.
411 	 */
412 	dasd_info->open_count = atomic_read(&block->open_count);
413 	if (!block->bdev)
414 		dasd_info->open_count++;
415 
416 	/*
417 	 * check if device is really formatted
418 	 * LDL / CDL was returned by 'fill_info'
419 	 */
420 	if ((base->state < DASD_STATE_READY) ||
421 	    (dasd_check_blocksize(block->bp_block)))
422 		dasd_info->format = DASD_FORMAT_NONE;
423 
424 	dasd_info->features |=
425 		((base->features & DASD_FEATURE_READONLY) != 0);
426 
427 	memcpy(dasd_info->type, base->discipline->name, 4);
428 
429 	if (block->request_queue->request_fn) {
430 		struct list_head *l;
431 #ifdef DASD_EXTENDED_PROFILING
432 		{
433 			struct list_head *l;
434 			spin_lock_irqsave(&block->lock, flags);
435 			list_for_each(l, &block->request_queue->queue_head)
436 				dasd_info->req_queue_len++;
437 			spin_unlock_irqrestore(&block->lock, flags);
438 		}
439 #endif				/* DASD_EXTENDED_PROFILING */
440 		spin_lock_irqsave(get_ccwdev_lock(base->cdev), flags);
441 		list_for_each(l, &base->ccw_queue)
442 			dasd_info->chanq_len++;
443 		spin_unlock_irqrestore(get_ccwdev_lock(base->cdev),
444 				       flags);
445 	}
446 
447 	rc = 0;
448 	if (copy_to_user(argp, dasd_info,
449 			 ((cmd == (unsigned int) BIODASDINFO2) ?
450 			  sizeof(struct dasd_information2_t) :
451 			  sizeof(struct dasd_information_t))))
452 		rc = -EFAULT;
453 	kfree(dasd_info);
454 	return rc;
455 }
456 
457 /*
458  * Set read only
459  */
460 static int
461 dasd_ioctl_set_ro(struct block_device *bdev, void __user *argp)
462 {
463 	struct dasd_device *base;
464 	int intval, rc;
465 
466 	if (!capable(CAP_SYS_ADMIN))
467 		return -EACCES;
468 	if (bdev != bdev->bd_contains)
469 		// ro setting is not allowed for partitions
470 		return -EINVAL;
471 	if (get_user(intval, (int __user *)argp))
472 		return -EFAULT;
473 	base = dasd_device_from_gendisk(bdev->bd_disk);
474 	if (!base)
475 		return -ENODEV;
476 	if (!intval && test_bit(DASD_FLAG_DEVICE_RO, &base->flags)) {
477 		dasd_put_device(base);
478 		return -EROFS;
479 	}
480 	set_disk_ro(bdev->bd_disk, intval);
481 	rc = dasd_set_feature(base->cdev, DASD_FEATURE_READONLY, intval);
482 	dasd_put_device(base);
483 	return rc;
484 }
485 
486 static int dasd_ioctl_readall_cmb(struct dasd_block *block, unsigned int cmd,
487 				  struct cmbdata __user *argp)
488 {
489 	size_t size = _IOC_SIZE(cmd);
490 	struct cmbdata data;
491 	int ret;
492 
493 	ret = cmf_readall(block->base->cdev, &data);
494 	if (!ret && copy_to_user(argp, &data, min(size, sizeof(*argp))))
495 		return -EFAULT;
496 	return ret;
497 }
498 
499 int dasd_ioctl(struct block_device *bdev, fmode_t mode,
500 	       unsigned int cmd, unsigned long arg)
501 {
502 	struct dasd_block *block;
503 	struct dasd_device *base;
504 	void __user *argp;
505 	int rc;
506 
507 	if (is_compat_task())
508 		argp = compat_ptr(arg);
509 	else
510 		argp = (void __user *)arg;
511 
512 	if ((_IOC_DIR(cmd) != _IOC_NONE) && !arg) {
513 		PRINT_DEBUG("empty data ptr");
514 		return -EINVAL;
515 	}
516 
517 	base = dasd_device_from_gendisk(bdev->bd_disk);
518 	if (!base)
519 		return -ENODEV;
520 	block = base->block;
521 	rc = 0;
522 	switch (cmd) {
523 	case BIODASDDISABLE:
524 		rc = dasd_ioctl_disable(bdev);
525 		break;
526 	case BIODASDENABLE:
527 		rc = dasd_ioctl_enable(bdev);
528 		break;
529 	case BIODASDQUIESCE:
530 		rc = dasd_ioctl_quiesce(block);
531 		break;
532 	case BIODASDRESUME:
533 		rc = dasd_ioctl_resume(block);
534 		break;
535 	case BIODASDABORTIO:
536 		rc = dasd_ioctl_abortio(block);
537 		break;
538 	case BIODASDALLOWIO:
539 		rc = dasd_ioctl_allowio(block);
540 		break;
541 	case BIODASDFMT:
542 		rc = dasd_ioctl_format(bdev, argp);
543 		break;
544 	case BIODASDINFO:
545 		rc = dasd_ioctl_information(block, cmd, argp);
546 		break;
547 	case BIODASDINFO2:
548 		rc = dasd_ioctl_information(block, cmd, argp);
549 		break;
550 	case BIODASDPRRD:
551 		rc = dasd_ioctl_read_profile(block, argp);
552 		break;
553 	case BIODASDPRRST:
554 		rc = dasd_ioctl_reset_profile(block);
555 		break;
556 	case BLKROSET:
557 		rc = dasd_ioctl_set_ro(bdev, argp);
558 		break;
559 	case DASDAPIVER:
560 		rc = dasd_ioctl_api_version(argp);
561 		break;
562 	case BIODASDCMFENABLE:
563 		rc = enable_cmf(base->cdev);
564 		break;
565 	case BIODASDCMFDISABLE:
566 		rc = disable_cmf(base->cdev);
567 		break;
568 	case BIODASDREADALLCMB:
569 		rc = dasd_ioctl_readall_cmb(block, cmd, argp);
570 		break;
571 	default:
572 		/* if the discipline has an ioctl method try it. */
573 		rc = -ENOTTY;
574 		if (base->discipline->ioctl)
575 			rc = base->discipline->ioctl(block, cmd, argp);
576 	}
577 	dasd_put_device(base);
578 	return rc;
579 }
580