dasd_ioctl.c

  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#include <linux/interrupt.h>
 14#include <linux/export.h>
 15#include <linux/major.h>
 16#include <linux/fs.h>
 17#include <linux/blkpg.h>
 18#include <linux/slab.h>
 19#include <asm/ccwdev.h>
 20#include <asm/schid.h>
 21#include <asm/cmb.h>
 22#include <linux/uaccess.h>
 23#include <linux/dasd_mod.h>
 24
 25#include "dasd_int.h"
 26
 27static int
 28dasd_ioctl_api_version(void __user *argp)
 29{
 30	int ver = DASD_API_VERSION;
 31	return put_user(ver, (int __user *)argp);
 32}
 33
 34/*
 35 * Enable device.
 36 * used by dasdfmt after BIODASDDISABLE to retrigger blocksize detection
 37 */
 38static int
 39dasd_ioctl_enable(struct block_device *bdev)
 40{
 41	struct dasd_device *base;
 42
 43	if (!capable(CAP_SYS_ADMIN))
 44		return -EACCES;
 45
 46	base = dasd_device_from_gendisk(bdev->bd_disk);
 47	if (!base)
 48		return -ENODEV;
 49
 50	dasd_enable_device(base);
 51	dasd_put_device(base);
 52	return 0;
 53}
 54
 55/*
 56 * Disable device.
 57 * Used by dasdfmt. Disable I/O operations but allow ioctls.
 58 */
 59static int
 60dasd_ioctl_disable(struct block_device *bdev)
 61{
 62	struct dasd_device *base;
 63
 64	if (!capable(CAP_SYS_ADMIN))
 65		return -EACCES;
 66
 67	base = dasd_device_from_gendisk(bdev->bd_disk);
 68	if (!base)
 69		return -ENODEV;
 70	/*
 71	 * Man this is sick. We don't do a real disable but only downgrade
 72	 * the device to DASD_STATE_BASIC. The reason is that dasdfmt uses
 73	 * BIODASDDISABLE to disable accesses to the device via the block
 74	 * device layer but it still wants to do i/o on the device by
 75	 * using the BIODASDFMT ioctl. Therefore the correct state for the
 76	 * device is DASD_STATE_BASIC that allows to do basic i/o.
 77	 */
 78	dasd_set_target_state(base, DASD_STATE_BASIC);
 79	/*
 80	 * Set i_size to zero, since read, write, etc. check against this
 81	 * value.
 82	 */
 83	set_capacity(bdev->bd_disk, 0);
 84	dasd_put_device(base);
 85	return 0;
 86}
 87
 88/*
 89 * Quiesce device.
 90 */
 91static int dasd_ioctl_quiesce(struct dasd_block *block)
 92{
 93	unsigned long flags;
 94	struct dasd_device *base;
 95
 96	base = block->base;
 97	if (!capable (CAP_SYS_ADMIN))
 98		return -EACCES;
 99
100	pr_info("%s: The DASD has been put in the quiesce "
101		"state\n", dev_name(&base->cdev->dev));
102	spin_lock_irqsave(get_ccwdev_lock(base->cdev), flags);
103	dasd_device_set_stop_bits(base, DASD_STOPPED_QUIESCE);
104	spin_unlock_irqrestore(get_ccwdev_lock(base->cdev), flags);
105	return 0;
106}
107
108
109/*
110 * Resume device.
111 */
112static int dasd_ioctl_resume(struct dasd_block *block)
113{
114	unsigned long flags;
115	struct dasd_device *base;
116
117	base = block->base;
118	if (!capable (CAP_SYS_ADMIN))
119		return -EACCES;
120
121	pr_info("%s: I/O operations have been resumed "
122		"on the DASD\n", dev_name(&base->cdev->dev));
123	spin_lock_irqsave(get_ccwdev_lock(base->cdev), flags);
124	dasd_device_remove_stop_bits(base, DASD_STOPPED_QUIESCE);
125	spin_unlock_irqrestore(get_ccwdev_lock(base->cdev), flags);
126
127	dasd_schedule_block_bh(block);
128	dasd_schedule_device_bh(base);
129	return 0;
130}
131
132/*
133 * Abort all failfast I/O on a device.
134 */
135static int dasd_ioctl_abortio(struct dasd_block *block)
136{
137	unsigned long flags;
138	struct dasd_device *base;
139	struct dasd_ccw_req *cqr, *n;
140
141	base = block->base;
142	if (!capable(CAP_SYS_ADMIN))
143		return -EACCES;
144
145	if (test_and_set_bit(DASD_FLAG_ABORTALL, &base->flags))
146		return 0;
147	DBF_DEV_EVENT(DBF_NOTICE, base, "%s", "abortall flag set");
148
149	spin_lock_irqsave(&block->request_queue_lock, flags);
150	spin_lock(&block->queue_lock);
151	list_for_each_entry_safe(cqr, n, &block->ccw_queue, blocklist) {
152		if (test_bit(DASD_CQR_FLAGS_FAILFAST, &cqr->flags) &&
153		    cqr->callback_data &&
154		    cqr->callback_data != DASD_SLEEPON_START_TAG &&
155		    cqr->callback_data != DASD_SLEEPON_END_TAG) {
156			spin_unlock(&block->queue_lock);
157			blk_abort_request(cqr->callback_data);
158			spin_lock(&block->queue_lock);
159		}
160	}
161	spin_unlock(&block->queue_lock);
162	spin_unlock_irqrestore(&block->request_queue_lock, flags);
163
164	dasd_schedule_block_bh(block);
165	return 0;
166}
167
168/*
169 * Allow I/O on a device
170 */
171static int dasd_ioctl_allowio(struct dasd_block *block)
172{
173	struct dasd_device *base;
174
175	base = block->base;
176	if (!capable(CAP_SYS_ADMIN))
177		return -EACCES;
178
179	if (test_and_clear_bit(DASD_FLAG_ABORTALL, &base->flags))
180		DBF_DEV_EVENT(DBF_NOTICE, base, "%s", "abortall flag unset");
181
182	return 0;
183}
184
185/*
186 * performs formatting of _device_ according to _fdata_
187 * Note: The discipline's format_function is assumed to deliver formatting
188 * commands to format multiple units of the device. In terms of the ECKD
189 * devices this means CCWs are generated to format multiple tracks.
190 */
191static int
192dasd_format(struct dasd_block *block, struct format_data_t *fdata)
193{
194	struct dasd_device *base;
195	int rc;
196
197	base = block->base;
198	if (base->discipline->format_device == NULL)
199		return -EPERM;
200
201	if (base->state != DASD_STATE_BASIC) {
202		pr_warn("%s: The DASD cannot be formatted while it is enabled\n",
203			dev_name(&base->cdev->dev));
204		return -EBUSY;
205	}
206
207	DBF_DEV_EVENT(DBF_NOTICE, base,
208		      "formatting units %u to %u (%u B blocks) flags %u",
209		      fdata->start_unit,
210		      fdata->stop_unit, fdata->blksize, fdata->intensity);
211
212	/* Since dasdfmt keeps the device open after it was disabled,
213	 * there still exists an inode for this device.
214	 * We must update i_blkbits, otherwise we might get errors when
215	 * enabling the device later.
216	 */
217	if (fdata->start_unit == 0) {
218		block->gdp->part0->bd_mapping->host->i_blkbits =
219			blksize_bits(fdata->blksize);
220	}
221
222	rc = base->discipline->format_device(base, fdata, 1);
223	if (rc == -EAGAIN)
224		rc = base->discipline->format_device(base, fdata, 0);
225
226	return rc;
227}
228
229static int dasd_check_format(struct dasd_block *block,
230			     struct format_check_t *cdata)
231{
232	struct dasd_device *base;
233	int rc;
234
235	base = block->base;
236	if (!base->discipline->check_device_format)
237		return -ENOTTY;
238
239	rc = base->discipline->check_device_format(base, cdata, 1);
240	if (rc == -EAGAIN)
241		rc = base->discipline->check_device_format(base, cdata, 0);
242
243	return rc;
244}
245
246/*
247 * Format device.
248 */
249static int
250dasd_ioctl_format(struct block_device *bdev, void __user *argp)
251{
252	struct dasd_device *base;
253	struct format_data_t fdata;
254	int rc;
255
256	if (!capable(CAP_SYS_ADMIN))
257		return -EACCES;
258	if (!argp)
259		return -EINVAL;
260	base = dasd_device_from_gendisk(bdev->bd_disk);
261	if (!base)
262		return -ENODEV;
263	if (base->features & DASD_FEATURE_READONLY ||
264	    test_bit(DASD_FLAG_DEVICE_RO, &base->flags)) {
265		dasd_put_device(base);
266		return -EROFS;
267	}
268	if (copy_from_user(&fdata, argp, sizeof(struct format_data_t))) {
269		dasd_put_device(base);
270		return -EFAULT;
271	}
272	if (bdev_is_partition(bdev)) {
273		pr_warn("%s: The specified DASD is a partition and cannot be formatted\n",
274			dev_name(&base->cdev->dev));
275		dasd_put_device(base);
276		return -EINVAL;
277	}
278	rc = dasd_format(base->block, &fdata);
279	dasd_put_device(base);
280
281	return rc;
282}
283
284/*
285 * Check device format
286 */
287static int dasd_ioctl_check_format(struct block_device *bdev, void __user *argp)
288{
289	struct format_check_t cdata;
290	struct dasd_device *base;
291	int rc = 0;
292
293	if (!argp)
294		return -EINVAL;
295
296	base = dasd_device_from_gendisk(bdev->bd_disk);
297	if (!base)
298		return -ENODEV;
299	if (bdev_is_partition(bdev)) {
300		pr_warn("%s: The specified DASD is a partition and cannot be checked\n",
301			dev_name(&base->cdev->dev));
302		rc = -EINVAL;
303		goto out_err;
304	}
305
306	if (copy_from_user(&cdata, argp, sizeof(cdata))) {
307		rc = -EFAULT;
308		goto out_err;
309	}
310
311	rc = dasd_check_format(base->block, &cdata);
312	if (rc)
313		goto out_err;
314
315	if (copy_to_user(argp, &cdata, sizeof(cdata)))
316		rc = -EFAULT;
317
318out_err:
319	dasd_put_device(base);
320
321	return rc;
322}
323
324static int dasd_release_space(struct dasd_device *device,
325			      struct format_data_t *rdata)
326{
327	if (!device->discipline->is_ese && !device->discipline->is_ese(device))
328		return -ENOTSUPP;
329	if (!device->discipline->release_space)
330		return -ENOTSUPP;
331
332	return device->discipline->release_space(device, rdata);
333}
334
335/*
336 * Release allocated space
337 */
338static int dasd_ioctl_release_space(struct block_device *bdev, void __user *argp)
339{
340	struct format_data_t rdata;
341	struct dasd_device *base;
342	int rc = 0;
343
344	if (!capable(CAP_SYS_ADMIN))
345		return -EACCES;
346	if (!argp)
347		return -EINVAL;
348
349	base = dasd_device_from_gendisk(bdev->bd_disk);
350	if (!base)
351		return -ENODEV;
352	if (base->features & DASD_FEATURE_READONLY ||
353	    test_bit(DASD_FLAG_DEVICE_RO, &base->flags)) {
354		rc = -EROFS;
355		goto out_err;
356	}
357	if (bdev_is_partition(bdev)) {
358		pr_warn("%s: The specified DASD is a partition and tracks cannot be released\n",
359			dev_name(&base->cdev->dev));
360		rc = -EINVAL;
361		goto out_err;
362	}
363
364	if (copy_from_user(&rdata, argp, sizeof(rdata))) {
365		rc = -EFAULT;
366		goto out_err;
367	}
368
369	rc = dasd_release_space(base, &rdata);
370
371out_err:
372	dasd_put_device(base);
373
374	return rc;
375}
376
377/*
378 * Swap driver iternal copy relation.
379 */
380static int
381dasd_ioctl_copy_pair_swap(struct block_device *bdev, void __user *argp)
382{
383	struct dasd_copypair_swap_data_t data;
384	struct dasd_device *device;
385	int rc;
386
387	if (!capable(CAP_SYS_ADMIN))
388		return -EACCES;
389
390	device = dasd_device_from_gendisk(bdev->bd_disk);
391	if (!device)
392		return -ENODEV;
393
394	if (copy_from_user(&data, argp, sizeof(struct dasd_copypair_swap_data_t))) {
395		dasd_put_device(device);
396		return -EFAULT;
397	}
398	if (memchr_inv(data.reserved, 0, sizeof(data.reserved))) {
399		pr_warn("%s: Invalid swap data specified\n",
400			dev_name(&device->cdev->dev));
401		dasd_put_device(device);
402		return DASD_COPYPAIRSWAP_INVALID;
403	}
404	if (bdev_is_partition(bdev)) {
405		pr_warn("%s: The specified DASD is a partition and cannot be swapped\n",
406			dev_name(&device->cdev->dev));
407		dasd_put_device(device);
408		return DASD_COPYPAIRSWAP_INVALID;
409	}
410	if (!device->copy) {
411		pr_warn("%s: The specified DASD has no copy pair set up\n",
412			dev_name(&device->cdev->dev));
413		dasd_put_device(device);
414		return -ENODEV;
415	}
416	if (!device->discipline->copy_pair_swap) {
417		dasd_put_device(device);
418		return -EOPNOTSUPP;
419	}
420	rc = device->discipline->copy_pair_swap(device, data.primary,
421						data.secondary);
422	dasd_put_device(device);
423
424	return rc;
425}
426
427#ifdef CONFIG_DASD_PROFILE
428/*
429 * Reset device profile information
430 */
431static int dasd_ioctl_reset_profile(struct dasd_block *block)
432{
433	dasd_profile_reset(&block->profile);
434	return 0;
435}
436
437/*
438 * Return device profile information
439 */
440static int dasd_ioctl_read_profile(struct dasd_block *block, void __user *argp)
441{
442	struct dasd_profile_info_t *data;
443	int rc = 0;
444
445	data = kmalloc(sizeof(*data), GFP_KERNEL);
446	if (!data)
447		return -ENOMEM;
448
449	spin_lock_bh(&block->profile.lock);
450	if (block->profile.data) {
451		data->dasd_io_reqs = block->profile.data->dasd_io_reqs;
452		data->dasd_io_sects = block->profile.data->dasd_io_sects;
453		memcpy(data->dasd_io_secs, block->profile.data->dasd_io_secs,
454		       sizeof(data->dasd_io_secs));
455		memcpy(data->dasd_io_times, block->profile.data->dasd_io_times,
456		       sizeof(data->dasd_io_times));
457		memcpy(data->dasd_io_timps, block->profile.data->dasd_io_timps,
458		       sizeof(data->dasd_io_timps));
459		memcpy(data->dasd_io_time1, block->profile.data->dasd_io_time1,
460		       sizeof(data->dasd_io_time1));
461		memcpy(data->dasd_io_time2, block->profile.data->dasd_io_time2,
462		       sizeof(data->dasd_io_time2));
463		memcpy(data->dasd_io_time2ps,
464		       block->profile.data->dasd_io_time2ps,
465		       sizeof(data->dasd_io_time2ps));
466		memcpy(data->dasd_io_time3, block->profile.data->dasd_io_time3,
467		       sizeof(data->dasd_io_time3));
468		memcpy(data->dasd_io_nr_req,
469		       block->profile.data->dasd_io_nr_req,
470		       sizeof(data->dasd_io_nr_req));
471		spin_unlock_bh(&block->profile.lock);
472	} else {
473		spin_unlock_bh(&block->profile.lock);
474		rc = -EIO;
475		goto out;
476	}
477	if (copy_to_user(argp, data, sizeof(*data)))
478		rc = -EFAULT;
479out:
480	kfree(data);
481	return rc;
482}
483#else
484static int dasd_ioctl_reset_profile(struct dasd_block *block)
485{
486	return -ENOTTY;
487}
488
489static int dasd_ioctl_read_profile(struct dasd_block *block, void __user *argp)
490{
491	return -ENOTTY;
492}
493#endif
494
495/*
496 * Return dasd information. Used for BIODASDINFO and BIODASDINFO2.
497 */
498static int __dasd_ioctl_information(struct dasd_block *block,
499		struct dasd_information2_t *dasd_info)
500{
501	struct subchannel_id sch_id;
502	struct ccw_dev_id dev_id;
503	struct dasd_device *base;
504	struct ccw_device *cdev;
505	struct list_head *l;
506	unsigned long flags;
507	int rc;
508
509	base = block->base;
510	if (!base->discipline || !base->discipline->fill_info)
511		return -EINVAL;
512
513	rc = base->discipline->fill_info(base, dasd_info);
514	if (rc)
515		return rc;
516
517	cdev = base->cdev;
518	ccw_device_get_id(cdev, &dev_id);
519	ccw_device_get_schid(cdev, &sch_id);
520
521	dasd_info->devno = dev_id.devno;
522	dasd_info->schid = sch_id.sch_no;
523	dasd_info->cu_type = cdev->id.cu_type;
524	dasd_info->cu_model = cdev->id.cu_model;
525	dasd_info->dev_type = cdev->id.dev_type;
526	dasd_info->dev_model = cdev->id.dev_model;
527	dasd_info->status = base->state;
528	/*
529	 * The open_count is increased for every opener, that includes
530	 * the blkdev_get in dasd_scan_partitions.
531	 * This must be hidden from user-space.
532	 */
533	dasd_info->open_count = atomic_read(&block->open_count);
534	if (!block->bdev_file)
535		dasd_info->open_count++;
536
537	/*
538	 * check if device is really formatted
539	 * LDL / CDL was returned by 'fill_info'
540	 */
541	if ((base->state < DASD_STATE_READY) ||
542	    (dasd_check_blocksize(block->bp_block)))
543		dasd_info->format = DASD_FORMAT_NONE;
544
545	dasd_info->features |=
546		((base->features & DASD_FEATURE_READONLY) != 0);
547
548	memcpy(dasd_info->type, base->discipline->name, 4);
549
550	spin_lock_irqsave(get_ccwdev_lock(base->cdev), flags);
551	list_for_each(l, &base->ccw_queue)
552		dasd_info->chanq_len++;
553	spin_unlock_irqrestore(get_ccwdev_lock(base->cdev), flags);
554	return 0;
555}
556
557static int dasd_ioctl_information(struct dasd_block *block, void __user *argp,
558		size_t copy_size)
559{
560	struct dasd_information2_t *dasd_info;
561	int error;
562
563	dasd_info = kzalloc(sizeof(*dasd_info), GFP_KERNEL);
564	if (!dasd_info)
565		return -ENOMEM;
566
567	error = __dasd_ioctl_information(block, dasd_info);
568	if (!error && copy_to_user(argp, dasd_info, copy_size))
569		error = -EFAULT;
570	kfree(dasd_info);
571	return error;
572}
573
574/*
575 * Set read only
576 */
577int dasd_set_read_only(struct block_device *bdev, bool ro)
578{
579	struct dasd_device *base;
580	int rc;
581
582	/* do not manipulate hardware state for partitions */
583	if (bdev_is_partition(bdev))
584		return 0;
585
586	base = dasd_device_from_gendisk(bdev->bd_disk);
587	if (!base)
588		return -ENODEV;
589	if (!ro && test_bit(DASD_FLAG_DEVICE_RO, &base->flags))
590		rc = -EROFS;
591	else
592		rc = dasd_set_feature(base->cdev, DASD_FEATURE_READONLY, ro);
593	dasd_put_device(base);
594	return rc;
595}
596
597static int dasd_ioctl_readall_cmb(struct dasd_block *block, unsigned int cmd,
598				  struct cmbdata __user *argp)
599{
600	size_t size = _IOC_SIZE(cmd);
601	struct cmbdata data;
602	int ret;
603
604	ret = cmf_readall(block->base->cdev, &data);
605	if (!ret && copy_to_user(argp, &data, min(size, sizeof(*argp))))
606		return -EFAULT;
607	return ret;
608}
609
610int dasd_ioctl(struct block_device *bdev, blk_mode_t mode,
611	       unsigned int cmd, unsigned long arg)
612{
613	struct dasd_block *block;
614	struct dasd_device *base;
615	void __user *argp;
616	int rc;
617
618	argp = (void __user *)arg;
619
620	if ((_IOC_DIR(cmd) != _IOC_NONE) && !arg)
621		return -EINVAL;
622
623	base = dasd_device_from_gendisk(bdev->bd_disk);
624	if (!base)
625		return -ENODEV;
626	block = base->block;
627	rc = 0;
628	switch (cmd) {
629	case BIODASDDISABLE:
630		rc = dasd_ioctl_disable(bdev);
631		break;
632	case BIODASDENABLE:
633		rc = dasd_ioctl_enable(bdev);
634		break;
635	case BIODASDQUIESCE:
636		rc = dasd_ioctl_quiesce(block);
637		break;
638	case BIODASDRESUME:
639		rc = dasd_ioctl_resume(block);
640		break;
641	case BIODASDABORTIO:
642		rc = dasd_ioctl_abortio(block);
643		break;
644	case BIODASDALLOWIO:
645		rc = dasd_ioctl_allowio(block);
646		break;
647	case BIODASDFMT:
648		rc = dasd_ioctl_format(bdev, argp);
649		break;
650	case BIODASDCHECKFMT:
651		rc = dasd_ioctl_check_format(bdev, argp);
652		break;
653	case BIODASDINFO:
654		rc = dasd_ioctl_information(block, argp,
655				sizeof(struct dasd_information_t));
656		break;
657	case BIODASDINFO2:
658		rc = dasd_ioctl_information(block, argp,
659				sizeof(struct dasd_information2_t));
660		break;
661	case BIODASDPRRD:
662		rc = dasd_ioctl_read_profile(block, argp);
663		break;
664	case BIODASDPRRST:
665		rc = dasd_ioctl_reset_profile(block);
666		break;
667	case DASDAPIVER:
668		rc = dasd_ioctl_api_version(argp);
669		break;
670	case BIODASDCMFENABLE:
671		rc = enable_cmf(base->cdev);
672		break;
673	case BIODASDCMFDISABLE:
674		rc = disable_cmf(base->cdev);
675		break;
676	case BIODASDREADALLCMB:
677		rc = dasd_ioctl_readall_cmb(block, cmd, argp);
678		break;
679	case BIODASDRAS:
680		rc = dasd_ioctl_release_space(bdev, argp);
681		break;
682	case BIODASDCOPYPAIRSWAP:
683		rc = dasd_ioctl_copy_pair_swap(bdev, argp);
684		break;
685	default:
686		/* if the discipline has an ioctl method try it. */
687		rc = -ENOTTY;
688		if (base->discipline->ioctl)
689			rc = base->discipline->ioctl(block, cmd, argp);
690	}
691	dasd_put_device(base);
692	return rc;
693}
694
695
696/**
697 * dasd_biodasdinfo() - fill out the dasd information structure
698 * @disk: [in] pointer to gendisk structure that references a DASD
699 * @info: [out] pointer to the dasd_information2_t structure
700 *
701 * Provide access to DASD specific information.
702 * The gendisk structure is checked if it belongs to the DASD driver by
703 * comparing the gendisk->fops pointer.
704 * If it does not belong to the DASD driver -EINVAL is returned.
705 * Otherwise the provided dasd_information2_t structure is filled out.
706 *
707 * Returns:
708 *   %0 on success and a negative error value on failure.
709 */
710int dasd_biodasdinfo(struct gendisk *disk, struct dasd_information2_t *info)
711{
712	struct dasd_device *base;
713	int error;
714
715	if (disk->fops != &dasd_device_operations)
716		return -EINVAL;
717
718	base = dasd_device_from_gendisk(disk);
719	if (!base)
720		return -ENODEV;
721	error = __dasd_ioctl_information(base->block, info);
722	dasd_put_device(base);
723	return error;
724}
725/* export that symbol_get in partition detection is possible */
726EXPORT_SYMBOL_GPL(dasd_biodasdinfo);