xref: /openbmc/linux/drivers/s390/block/dasd_ioctl.c (revision feac8c8b)
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * Author(s)......: Holger Smolinski <Holger.Smolinski@de.ibm.com>
4  *		    Horst Hummel <Horst.Hummel@de.ibm.com>
5  *		    Carsten Otte <Cotte@de.ibm.com>
6  *		    Martin Schwidefsky <schwidefsky@de.ibm.com>
7  * Bugreports.to..: <Linux390@de.ibm.com>
8  * Copyright IBM Corp. 1999, 2001
9  *
10  * i/o controls for the dasd driver.
11  */
12 
13 #define KMSG_COMPONENT "dasd"
14 
15 #include <linux/interrupt.h>
16 #include <linux/compat.h>
17 #include <linux/major.h>
18 #include <linux/fs.h>
19 #include <linux/blkpg.h>
20 #include <linux/slab.h>
21 #include <asm/compat.h>
22 #include <asm/ccwdev.h>
23 #include <asm/schid.h>
24 #include <asm/cmb.h>
25 #include <linux/uaccess.h>
26 
27 /* This is ugly... */
28 #define PRINTK_HEADER "dasd_ioctl:"
29 
30 #include "dasd_int.h"
31 
32 
33 static int
34 dasd_ioctl_api_version(void __user *argp)
35 {
36 	int ver = DASD_API_VERSION;
37 	return put_user(ver, (int __user *)argp);
38 }
39 
40 /*
41  * Enable device.
42  * used by dasdfmt after BIODASDDISABLE to retrigger blocksize detection
43  */
44 static int
45 dasd_ioctl_enable(struct block_device *bdev)
46 {
47 	struct dasd_device *base;
48 
49 	if (!capable(CAP_SYS_ADMIN))
50 		return -EACCES;
51 
52 	base = dasd_device_from_gendisk(bdev->bd_disk);
53 	if (!base)
54 		return -ENODEV;
55 
56 	dasd_enable_device(base);
57 	/* Formatting the dasd device can change the capacity. */
58 	mutex_lock(&bdev->bd_mutex);
59 	i_size_write(bdev->bd_inode,
60 		     (loff_t)get_capacity(base->block->gdp) << 9);
61 	mutex_unlock(&bdev->bd_mutex);
62 	dasd_put_device(base);
63 	return 0;
64 }
65 
66 /*
67  * Disable device.
68  * Used by dasdfmt. Disable I/O operations but allow ioctls.
69  */
70 static int
71 dasd_ioctl_disable(struct block_device *bdev)
72 {
73 	struct dasd_device *base;
74 
75 	if (!capable(CAP_SYS_ADMIN))
76 		return -EACCES;
77 
78 	base = dasd_device_from_gendisk(bdev->bd_disk);
79 	if (!base)
80 		return -ENODEV;
81 	/*
82 	 * Man this is sick. We don't do a real disable but only downgrade
83 	 * the device to DASD_STATE_BASIC. The reason is that dasdfmt uses
84 	 * BIODASDDISABLE to disable accesses to the device via the block
85 	 * device layer but it still wants to do i/o on the device by
86 	 * using the BIODASDFMT ioctl. Therefore the correct state for the
87 	 * device is DASD_STATE_BASIC that allows to do basic i/o.
88 	 */
89 	dasd_set_target_state(base, DASD_STATE_BASIC);
90 	/*
91 	 * Set i_size to zero, since read, write, etc. check against this
92 	 * value.
93 	 */
94 	mutex_lock(&bdev->bd_mutex);
95 	i_size_write(bdev->bd_inode, 0);
96 	mutex_unlock(&bdev->bd_mutex);
97 	dasd_put_device(base);
98 	return 0;
99 }
100 
101 /*
102  * Quiesce device.
103  */
104 static int dasd_ioctl_quiesce(struct dasd_block *block)
105 {
106 	unsigned long flags;
107 	struct dasd_device *base;
108 
109 	base = block->base;
110 	if (!capable (CAP_SYS_ADMIN))
111 		return -EACCES;
112 
113 	pr_info("%s: The DASD has been put in the quiesce "
114 		"state\n", dev_name(&base->cdev->dev));
115 	spin_lock_irqsave(get_ccwdev_lock(base->cdev), flags);
116 	dasd_device_set_stop_bits(base, DASD_STOPPED_QUIESCE);
117 	spin_unlock_irqrestore(get_ccwdev_lock(base->cdev), flags);
118 	return 0;
119 }
120 
121 
122 /*
123  * Resume device.
124  */
125 static int dasd_ioctl_resume(struct dasd_block *block)
126 {
127 	unsigned long flags;
128 	struct dasd_device *base;
129 
130 	base = block->base;
131 	if (!capable (CAP_SYS_ADMIN))
132 		return -EACCES;
133 
134 	pr_info("%s: I/O operations have been resumed "
135 		"on the DASD\n", dev_name(&base->cdev->dev));
136 	spin_lock_irqsave(get_ccwdev_lock(base->cdev), flags);
137 	dasd_device_remove_stop_bits(base, DASD_STOPPED_QUIESCE);
138 	spin_unlock_irqrestore(get_ccwdev_lock(base->cdev), flags);
139 
140 	dasd_schedule_block_bh(block);
141 	return 0;
142 }
143 
144 /*
145  * Abort all failfast I/O on a device.
146  */
147 static int dasd_ioctl_abortio(struct dasd_block *block)
148 {
149 	unsigned long flags;
150 	struct dasd_device *base;
151 	struct dasd_ccw_req *cqr, *n;
152 
153 	base = block->base;
154 	if (!capable(CAP_SYS_ADMIN))
155 		return -EACCES;
156 
157 	if (test_and_set_bit(DASD_FLAG_ABORTALL, &base->flags))
158 		return 0;
159 	DBF_DEV_EVENT(DBF_NOTICE, base, "%s", "abortall flag set");
160 
161 	spin_lock_irqsave(&block->request_queue_lock, flags);
162 	spin_lock(&block->queue_lock);
163 	list_for_each_entry_safe(cqr, n, &block->ccw_queue, blocklist) {
164 		if (test_bit(DASD_CQR_FLAGS_FAILFAST, &cqr->flags) &&
165 		    cqr->callback_data &&
166 		    cqr->callback_data != DASD_SLEEPON_START_TAG &&
167 		    cqr->callback_data != DASD_SLEEPON_END_TAG) {
168 			spin_unlock(&block->queue_lock);
169 			blk_abort_request(cqr->callback_data);
170 			spin_lock(&block->queue_lock);
171 		}
172 	}
173 	spin_unlock(&block->queue_lock);
174 	spin_unlock_irqrestore(&block->request_queue_lock, flags);
175 
176 	dasd_schedule_block_bh(block);
177 	return 0;
178 }
179 
180 /*
181  * Allow I/O on a device
182  */
183 static int dasd_ioctl_allowio(struct dasd_block *block)
184 {
185 	struct dasd_device *base;
186 
187 	base = block->base;
188 	if (!capable(CAP_SYS_ADMIN))
189 		return -EACCES;
190 
191 	if (test_and_clear_bit(DASD_FLAG_ABORTALL, &base->flags))
192 		DBF_DEV_EVENT(DBF_NOTICE, base, "%s", "abortall flag unset");
193 
194 	return 0;
195 }
196 
197 /*
198  * performs formatting of _device_ according to _fdata_
199  * Note: The discipline's format_function is assumed to deliver formatting
200  * commands to format multiple units of the device. In terms of the ECKD
201  * devices this means CCWs are generated to format multiple tracks.
202  */
203 static int
204 dasd_format(struct dasd_block *block, struct format_data_t *fdata)
205 {
206 	struct dasd_device *base;
207 	int rc;
208 
209 	base = block->base;
210 	if (base->discipline->format_device == NULL)
211 		return -EPERM;
212 
213 	if (base->state != DASD_STATE_BASIC) {
214 		pr_warn("%s: The DASD cannot be formatted while it is enabled\n",
215 			dev_name(&base->cdev->dev));
216 		return -EBUSY;
217 	}
218 
219 	DBF_DEV_EVENT(DBF_NOTICE, base,
220 		      "formatting units %u to %u (%u B blocks) flags %u",
221 		      fdata->start_unit,
222 		      fdata->stop_unit, fdata->blksize, fdata->intensity);
223 
224 	/* Since dasdfmt keeps the device open after it was disabled,
225 	 * there still exists an inode for this device.
226 	 * We must update i_blkbits, otherwise we might get errors when
227 	 * enabling the device later.
228 	 */
229 	if (fdata->start_unit == 0) {
230 		struct block_device *bdev = bdget_disk(block->gdp, 0);
231 		bdev->bd_inode->i_blkbits = blksize_bits(fdata->blksize);
232 		bdput(bdev);
233 	}
234 
235 	rc = base->discipline->format_device(base, fdata, 1);
236 	if (rc == -EAGAIN)
237 		rc = base->discipline->format_device(base, fdata, 0);
238 
239 	return rc;
240 }
241 
242 static int dasd_check_format(struct dasd_block *block,
243 			     struct format_check_t *cdata)
244 {
245 	struct dasd_device *base;
246 	int rc;
247 
248 	base = block->base;
249 	if (!base->discipline->check_device_format)
250 		return -ENOTTY;
251 
252 	rc = base->discipline->check_device_format(base, cdata, 1);
253 	if (rc == -EAGAIN)
254 		rc = base->discipline->check_device_format(base, cdata, 0);
255 
256 	return rc;
257 }
258 
259 /*
260  * Format device.
261  */
262 static int
263 dasd_ioctl_format(struct block_device *bdev, void __user *argp)
264 {
265 	struct dasd_device *base;
266 	struct format_data_t fdata;
267 	int rc;
268 
269 	if (!capable(CAP_SYS_ADMIN))
270 		return -EACCES;
271 	if (!argp)
272 		return -EINVAL;
273 	base = dasd_device_from_gendisk(bdev->bd_disk);
274 	if (!base)
275 		return -ENODEV;
276 	if (base->features & DASD_FEATURE_READONLY ||
277 	    test_bit(DASD_FLAG_DEVICE_RO, &base->flags)) {
278 		dasd_put_device(base);
279 		return -EROFS;
280 	}
281 	if (copy_from_user(&fdata, argp, sizeof(struct format_data_t))) {
282 		dasd_put_device(base);
283 		return -EFAULT;
284 	}
285 	if (bdev != bdev->bd_contains) {
286 		pr_warn("%s: The specified DASD is a partition and cannot be formatted\n",
287 			dev_name(&base->cdev->dev));
288 		dasd_put_device(base);
289 		return -EINVAL;
290 	}
291 	rc = dasd_format(base->block, &fdata);
292 	dasd_put_device(base);
293 
294 	return rc;
295 }
296 
297 /*
298  * Check device format
299  */
300 static int dasd_ioctl_check_format(struct block_device *bdev, void __user *argp)
301 {
302 	struct format_check_t cdata;
303 	struct dasd_device *base;
304 	int rc = 0;
305 
306 	if (!argp)
307 		return -EINVAL;
308 
309 	base = dasd_device_from_gendisk(bdev->bd_disk);
310 	if (!base)
311 		return -ENODEV;
312 	if (bdev != bdev->bd_contains) {
313 		pr_warn("%s: The specified DASD is a partition and cannot be checked\n",
314 			dev_name(&base->cdev->dev));
315 		rc = -EINVAL;
316 		goto out_err;
317 	}
318 
319 	if (copy_from_user(&cdata, argp, sizeof(cdata))) {
320 		rc = -EFAULT;
321 		goto out_err;
322 	}
323 
324 	rc = dasd_check_format(base->block, &cdata);
325 	if (rc)
326 		goto out_err;
327 
328 	if (copy_to_user(argp, &cdata, sizeof(cdata)))
329 		rc = -EFAULT;
330 
331 out_err:
332 	dasd_put_device(base);
333 
334 	return rc;
335 }
336 
337 #ifdef CONFIG_DASD_PROFILE
338 /*
339  * Reset device profile information
340  */
341 static int dasd_ioctl_reset_profile(struct dasd_block *block)
342 {
343 	dasd_profile_reset(&block->profile);
344 	return 0;
345 }
346 
347 /*
348  * Return device profile information
349  */
350 static int dasd_ioctl_read_profile(struct dasd_block *block, void __user *argp)
351 {
352 	struct dasd_profile_info_t *data;
353 	int rc = 0;
354 
355 	data = kmalloc(sizeof(*data), GFP_KERNEL);
356 	if (!data)
357 		return -ENOMEM;
358 
359 	spin_lock_bh(&block->profile.lock);
360 	if (block->profile.data) {
361 		data->dasd_io_reqs = block->profile.data->dasd_io_reqs;
362 		data->dasd_io_sects = block->profile.data->dasd_io_sects;
363 		memcpy(data->dasd_io_secs, block->profile.data->dasd_io_secs,
364 		       sizeof(data->dasd_io_secs));
365 		memcpy(data->dasd_io_times, block->profile.data->dasd_io_times,
366 		       sizeof(data->dasd_io_times));
367 		memcpy(data->dasd_io_timps, block->profile.data->dasd_io_timps,
368 		       sizeof(data->dasd_io_timps));
369 		memcpy(data->dasd_io_time1, block->profile.data->dasd_io_time1,
370 		       sizeof(data->dasd_io_time1));
371 		memcpy(data->dasd_io_time2, block->profile.data->dasd_io_time2,
372 		       sizeof(data->dasd_io_time2));
373 		memcpy(data->dasd_io_time2ps,
374 		       block->profile.data->dasd_io_time2ps,
375 		       sizeof(data->dasd_io_time2ps));
376 		memcpy(data->dasd_io_time3, block->profile.data->dasd_io_time3,
377 		       sizeof(data->dasd_io_time3));
378 		memcpy(data->dasd_io_nr_req,
379 		       block->profile.data->dasd_io_nr_req,
380 		       sizeof(data->dasd_io_nr_req));
381 		spin_unlock_bh(&block->profile.lock);
382 	} else {
383 		spin_unlock_bh(&block->profile.lock);
384 		rc = -EIO;
385 		goto out;
386 	}
387 	if (copy_to_user(argp, data, sizeof(*data)))
388 		rc = -EFAULT;
389 out:
390 	kfree(data);
391 	return rc;
392 }
393 #else
394 static int dasd_ioctl_reset_profile(struct dasd_block *block)
395 {
396 	return -ENOTTY;
397 }
398 
399 static int dasd_ioctl_read_profile(struct dasd_block *block, void __user *argp)
400 {
401 	return -ENOTTY;
402 }
403 #endif
404 
405 /*
406  * Return dasd information. Used for BIODASDINFO and BIODASDINFO2.
407  */
408 static int dasd_ioctl_information(struct dasd_block *block,
409 				  unsigned int cmd, void __user *argp)
410 {
411 	struct dasd_information2_t *dasd_info;
412 	struct subchannel_id sch_id;
413 	struct ccw_dev_id dev_id;
414 	struct dasd_device *base;
415 	struct ccw_device *cdev;
416 	unsigned long flags;
417 	int rc;
418 
419 	base = block->base;
420 	if (!base->discipline || !base->discipline->fill_info)
421 		return -EINVAL;
422 
423 	dasd_info = kzalloc(sizeof(struct dasd_information2_t), GFP_KERNEL);
424 	if (dasd_info == NULL)
425 		return -ENOMEM;
426 
427 	rc = base->discipline->fill_info(base, dasd_info);
428 	if (rc) {
429 		kfree(dasd_info);
430 		return rc;
431 	}
432 
433 	cdev = base->cdev;
434 	ccw_device_get_id(cdev, &dev_id);
435 	ccw_device_get_schid(cdev, &sch_id);
436 
437 	dasd_info->devno = dev_id.devno;
438 	dasd_info->schid = sch_id.sch_no;
439 	dasd_info->cu_type = cdev->id.cu_type;
440 	dasd_info->cu_model = cdev->id.cu_model;
441 	dasd_info->dev_type = cdev->id.dev_type;
442 	dasd_info->dev_model = cdev->id.dev_model;
443 	dasd_info->status = base->state;
444 	/*
445 	 * The open_count is increased for every opener, that includes
446 	 * the blkdev_get in dasd_scan_partitions.
447 	 * This must be hidden from user-space.
448 	 */
449 	dasd_info->open_count = atomic_read(&block->open_count);
450 	if (!block->bdev)
451 		dasd_info->open_count++;
452 
453 	/*
454 	 * check if device is really formatted
455 	 * LDL / CDL was returned by 'fill_info'
456 	 */
457 	if ((base->state < DASD_STATE_READY) ||
458 	    (dasd_check_blocksize(block->bp_block)))
459 		dasd_info->format = DASD_FORMAT_NONE;
460 
461 	dasd_info->features |=
462 		((base->features & DASD_FEATURE_READONLY) != 0);
463 
464 	memcpy(dasd_info->type, base->discipline->name, 4);
465 
466 	if (block->request_queue->request_fn) {
467 		struct list_head *l;
468 #ifdef DASD_EXTENDED_PROFILING
469 		{
470 			struct list_head *l;
471 			spin_lock_irqsave(&block->lock, flags);
472 			list_for_each(l, &block->request_queue->queue_head)
473 				dasd_info->req_queue_len++;
474 			spin_unlock_irqrestore(&block->lock, flags);
475 		}
476 #endif				/* DASD_EXTENDED_PROFILING */
477 		spin_lock_irqsave(get_ccwdev_lock(base->cdev), flags);
478 		list_for_each(l, &base->ccw_queue)
479 			dasd_info->chanq_len++;
480 		spin_unlock_irqrestore(get_ccwdev_lock(base->cdev),
481 				       flags);
482 	}
483 
484 	rc = 0;
485 	if (copy_to_user(argp, dasd_info,
486 			 ((cmd == (unsigned int) BIODASDINFO2) ?
487 			  sizeof(struct dasd_information2_t) :
488 			  sizeof(struct dasd_information_t))))
489 		rc = -EFAULT;
490 	kfree(dasd_info);
491 	return rc;
492 }
493 
494 /*
495  * Set read only
496  */
497 static int
498 dasd_ioctl_set_ro(struct block_device *bdev, void __user *argp)
499 {
500 	struct dasd_device *base;
501 	int intval, rc;
502 
503 	if (!capable(CAP_SYS_ADMIN))
504 		return -EACCES;
505 	if (bdev != bdev->bd_contains)
506 		// ro setting is not allowed for partitions
507 		return -EINVAL;
508 	if (get_user(intval, (int __user *)argp))
509 		return -EFAULT;
510 	base = dasd_device_from_gendisk(bdev->bd_disk);
511 	if (!base)
512 		return -ENODEV;
513 	if (!intval && test_bit(DASD_FLAG_DEVICE_RO, &base->flags)) {
514 		dasd_put_device(base);
515 		return -EROFS;
516 	}
517 	set_disk_ro(bdev->bd_disk, intval);
518 	rc = dasd_set_feature(base->cdev, DASD_FEATURE_READONLY, intval);
519 	dasd_put_device(base);
520 	return rc;
521 }
522 
523 static int dasd_ioctl_readall_cmb(struct dasd_block *block, unsigned int cmd,
524 				  struct cmbdata __user *argp)
525 {
526 	size_t size = _IOC_SIZE(cmd);
527 	struct cmbdata data;
528 	int ret;
529 
530 	ret = cmf_readall(block->base->cdev, &data);
531 	if (!ret && copy_to_user(argp, &data, min(size, sizeof(*argp))))
532 		return -EFAULT;
533 	return ret;
534 }
535 
536 int dasd_ioctl(struct block_device *bdev, fmode_t mode,
537 	       unsigned int cmd, unsigned long arg)
538 {
539 	struct dasd_block *block;
540 	struct dasd_device *base;
541 	void __user *argp;
542 	int rc;
543 
544 	if (is_compat_task())
545 		argp = compat_ptr(arg);
546 	else
547 		argp = (void __user *)arg;
548 
549 	if ((_IOC_DIR(cmd) != _IOC_NONE) && !arg) {
550 		PRINT_DEBUG("empty data ptr");
551 		return -EINVAL;
552 	}
553 
554 	base = dasd_device_from_gendisk(bdev->bd_disk);
555 	if (!base)
556 		return -ENODEV;
557 	block = base->block;
558 	rc = 0;
559 	switch (cmd) {
560 	case BIODASDDISABLE:
561 		rc = dasd_ioctl_disable(bdev);
562 		break;
563 	case BIODASDENABLE:
564 		rc = dasd_ioctl_enable(bdev);
565 		break;
566 	case BIODASDQUIESCE:
567 		rc = dasd_ioctl_quiesce(block);
568 		break;
569 	case BIODASDRESUME:
570 		rc = dasd_ioctl_resume(block);
571 		break;
572 	case BIODASDABORTIO:
573 		rc = dasd_ioctl_abortio(block);
574 		break;
575 	case BIODASDALLOWIO:
576 		rc = dasd_ioctl_allowio(block);
577 		break;
578 	case BIODASDFMT:
579 		rc = dasd_ioctl_format(bdev, argp);
580 		break;
581 	case BIODASDCHECKFMT:
582 		rc = dasd_ioctl_check_format(bdev, argp);
583 		break;
584 	case BIODASDINFO:
585 		rc = dasd_ioctl_information(block, cmd, argp);
586 		break;
587 	case BIODASDINFO2:
588 		rc = dasd_ioctl_information(block, cmd, argp);
589 		break;
590 	case BIODASDPRRD:
591 		rc = dasd_ioctl_read_profile(block, argp);
592 		break;
593 	case BIODASDPRRST:
594 		rc = dasd_ioctl_reset_profile(block);
595 		break;
596 	case BLKROSET:
597 		rc = dasd_ioctl_set_ro(bdev, argp);
598 		break;
599 	case DASDAPIVER:
600 		rc = dasd_ioctl_api_version(argp);
601 		break;
602 	case BIODASDCMFENABLE:
603 		rc = enable_cmf(base->cdev);
604 		break;
605 	case BIODASDCMFDISABLE:
606 		rc = disable_cmf(base->cdev);
607 		break;
608 	case BIODASDREADALLCMB:
609 		rc = dasd_ioctl_readall_cmb(block, cmd, argp);
610 		break;
611 	default:
612 		/* if the discipline has an ioctl method try it. */
613 		rc = -ENOTTY;
614 		if (base->discipline->ioctl)
615 			rc = base->discipline->ioctl(block, cmd, argp);
616 	}
617 	dasd_put_device(base);
618 	return rc;
619 }
620