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/ccwdev.h>
22#include <asm/schid.h>
23#include <asm/cmb.h>
24#include <linux/uaccess.h>
25#include <linux/dasd_mod.h>
26
27/* This is ugly... */
28#define PRINTK_HEADER "dasd_ioctl:"
29
30#include "dasd_int.h"
31
32
33static int
34dasd_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 */
44static int
45dasd_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	dasd_put_device(base);
58	return 0;
59}
60
61/*
62 * Disable device.
63 * Used by dasdfmt. Disable I/O operations but allow ioctls.
64 */
65static int
66dasd_ioctl_disable(struct block_device *bdev)
67{
68	struct dasd_device *base;
69
70	if (!capable(CAP_SYS_ADMIN))
71		return -EACCES;
72
73	base = dasd_device_from_gendisk(bdev->bd_disk);
74	if (!base)
75		return -ENODEV;
76	/*
77	 * Man this is sick. We don't do a real disable but only downgrade
78	 * the device to DASD_STATE_BASIC. The reason is that dasdfmt uses
79	 * BIODASDDISABLE to disable accesses to the device via the block
80	 * device layer but it still wants to do i/o on the device by
81	 * using the BIODASDFMT ioctl. Therefore the correct state for the
82	 * device is DASD_STATE_BASIC that allows to do basic i/o.
83	 */
84	dasd_set_target_state(base, DASD_STATE_BASIC);
85	/*
86	 * Set i_size to zero, since read, write, etc. check against this
87	 * value.
88	 */
89	set_capacity(bdev->bd_disk, 0);
90	dasd_put_device(base);
91	return 0;
92}
93
94/*
95 * Quiesce device.
96 */
97static int dasd_ioctl_quiesce(struct dasd_block *block)
98{
99	unsigned long flags;
100	struct dasd_device *base;
101
102	base = block->base;
103	if (!capable (CAP_SYS_ADMIN))
104		return -EACCES;
105
106	pr_info("%s: The DASD has been put in the quiesce "
107		"state\n", dev_name(&base->cdev->dev));
108	spin_lock_irqsave(get_ccwdev_lock(base->cdev), flags);
109	dasd_device_set_stop_bits(base, DASD_STOPPED_QUIESCE);
110	spin_unlock_irqrestore(get_ccwdev_lock(base->cdev), flags);
111	return 0;
112}
113
114
115/*
116 * Resume device.
117 */
118static int dasd_ioctl_resume(struct dasd_block *block)
119{
120	unsigned long flags;
121	struct dasd_device *base;
122
123	base = block->base;
124	if (!capable (CAP_SYS_ADMIN))
125		return -EACCES;
126
127	pr_info("%s: I/O operations have been resumed "
128		"on the DASD\n", dev_name(&base->cdev->dev));
129	spin_lock_irqsave(get_ccwdev_lock(base->cdev), flags);
130	dasd_device_remove_stop_bits(base, DASD_STOPPED_QUIESCE);
131	spin_unlock_irqrestore(get_ccwdev_lock(base->cdev), flags);
132
133	dasd_schedule_block_bh(block);
134	dasd_schedule_device_bh(base);
135	return 0;
136}
137
138/*
139 * Abort all failfast I/O on a device.
140 */
141static int dasd_ioctl_abortio(struct dasd_block *block)
142{
143	unsigned long flags;
144	struct dasd_device *base;
145	struct dasd_ccw_req *cqr, *n;
146
147	base = block->base;
148	if (!capable(CAP_SYS_ADMIN))
149		return -EACCES;
150
151	if (test_and_set_bit(DASD_FLAG_ABORTALL, &base->flags))
152		return 0;
153	DBF_DEV_EVENT(DBF_NOTICE, base, "%s", "abortall flag set");
154
155	spin_lock_irqsave(&block->request_queue_lock, flags);
156	spin_lock(&block->queue_lock);
157	list_for_each_entry_safe(cqr, n, &block->ccw_queue, blocklist) {
158		if (test_bit(DASD_CQR_FLAGS_FAILFAST, &cqr->flags) &&
159		    cqr->callback_data &&
160		    cqr->callback_data != DASD_SLEEPON_START_TAG &&
161		    cqr->callback_data != DASD_SLEEPON_END_TAG) {
162			spin_unlock(&block->queue_lock);
163			blk_abort_request(cqr->callback_data);
164			spin_lock(&block->queue_lock);
165		}
166	}
167	spin_unlock(&block->queue_lock);
168	spin_unlock_irqrestore(&block->request_queue_lock, flags);
169
170	dasd_schedule_block_bh(block);
171	return 0;
172}
173
174/*
175 * Allow I/O on a device
176 */
177static int dasd_ioctl_allowio(struct dasd_block *block)
178{
179	struct dasd_device *base;
180
181	base = block->base;
182	if (!capable(CAP_SYS_ADMIN))
183		return -EACCES;
184
185	if (test_and_clear_bit(DASD_FLAG_ABORTALL, &base->flags))
186		DBF_DEV_EVENT(DBF_NOTICE, base, "%s", "abortall flag unset");
187
188	return 0;
189}
190
191/*
192 * performs formatting of _device_ according to _fdata_
193 * Note: The discipline's format_function is assumed to deliver formatting
194 * commands to format multiple units of the device. In terms of the ECKD
195 * devices this means CCWs are generated to format multiple tracks.
196 */
197static int
198dasd_format(struct dasd_block *block, struct format_data_t *fdata)
199{
200	struct dasd_device *base;
201	int rc;
202
203	base = block->base;
204	if (base->discipline->format_device == NULL)
205		return -EPERM;
206
207	if (base->state != DASD_STATE_BASIC) {
208		pr_warn("%s: The DASD cannot be formatted while it is enabled\n",
209			dev_name(&base->cdev->dev));
210		return -EBUSY;
211	}
212
213	DBF_DEV_EVENT(DBF_NOTICE, base,
214		      "formatting units %u to %u (%u B blocks) flags %u",
215		      fdata->start_unit,
216		      fdata->stop_unit, fdata->blksize, fdata->intensity);
217
218	/* Since dasdfmt keeps the device open after it was disabled,
219	 * there still exists an inode for this device.
220	 * We must update i_blkbits, otherwise we might get errors when
221	 * enabling the device later.
222	 */
223	if (fdata->start_unit == 0) {
224		block->gdp->part0->bd_inode->i_blkbits =
225			blksize_bits(fdata->blksize);
226	}
227
228	rc = base->discipline->format_device(base, fdata, 1);
229	if (rc == -EAGAIN)
230		rc = base->discipline->format_device(base, fdata, 0);
231
232	return rc;
233}
234
235static int dasd_check_format(struct dasd_block *block,
236			     struct format_check_t *cdata)
237{
238	struct dasd_device *base;
239	int rc;
240
241	base = block->base;
242	if (!base->discipline->check_device_format)
243		return -ENOTTY;
244
245	rc = base->discipline->check_device_format(base, cdata, 1);
246	if (rc == -EAGAIN)
247		rc = base->discipline->check_device_format(base, cdata, 0);
248
249	return rc;
250}
251
252/*
253 * Format device.
254 */
255static int
256dasd_ioctl_format(struct block_device *bdev, void __user *argp)
257{
258	struct dasd_device *base;
259	struct format_data_t fdata;
260	int rc;
261
262	if (!capable(CAP_SYS_ADMIN))
263		return -EACCES;
264	if (!argp)
265		return -EINVAL;
266	base = dasd_device_from_gendisk(bdev->bd_disk);
267	if (!base)
268		return -ENODEV;
269	if (base->features & DASD_FEATURE_READONLY ||
270	    test_bit(DASD_FLAG_DEVICE_RO, &base->flags)) {
271		dasd_put_device(base);
272		return -EROFS;
273	}
274	if (copy_from_user(&fdata, argp, sizeof(struct format_data_t))) {
275		dasd_put_device(base);
276		return -EFAULT;
277	}
278	if (bdev_is_partition(bdev)) {
279		pr_warn("%s: The specified DASD is a partition and cannot be formatted\n",
280			dev_name(&base->cdev->dev));
281		dasd_put_device(base);
282		return -EINVAL;
283	}
284	rc = dasd_format(base->block, &fdata);
285	dasd_put_device(base);
286
287	return rc;
288}
289
290/*
291 * Check device format
292 */
293static int dasd_ioctl_check_format(struct block_device *bdev, void __user *argp)
294{
295	struct format_check_t cdata;
296	struct dasd_device *base;
297	int rc = 0;
298
299	if (!argp)
300		return -EINVAL;
301
302	base = dasd_device_from_gendisk(bdev->bd_disk);
303	if (!base)
304		return -ENODEV;
305	if (bdev_is_partition(bdev)) {
306		pr_warn("%s: The specified DASD is a partition and cannot be checked\n",
307			dev_name(&base->cdev->dev));
308		rc = -EINVAL;
309		goto out_err;
310	}
311
312	if (copy_from_user(&cdata, argp, sizeof(cdata))) {
313		rc = -EFAULT;
314		goto out_err;
315	}
316
317	rc = dasd_check_format(base->block, &cdata);
318	if (rc)
319		goto out_err;
320
321	if (copy_to_user(argp, &cdata, sizeof(cdata)))
322		rc = -EFAULT;
323
324out_err:
325	dasd_put_device(base);
326
327	return rc;
328}
329
330static int dasd_release_space(struct dasd_device *device,
331			      struct format_data_t *rdata)
332{
333	if (!device->discipline->is_ese && !device->discipline->is_ese(device))
334		return -ENOTSUPP;
335	if (!device->discipline->release_space)
336		return -ENOTSUPP;
337
338	return device->discipline->release_space(device, rdata);
339}
340
341/*
342 * Release allocated space
343 */
344static int dasd_ioctl_release_space(struct block_device *bdev, void __user *argp)
345{
346	struct format_data_t rdata;
347	struct dasd_device *base;
348	int rc = 0;
349
350	if (!capable(CAP_SYS_ADMIN))
351		return -EACCES;
352	if (!argp)
353		return -EINVAL;
354
355	base = dasd_device_from_gendisk(bdev->bd_disk);
356	if (!base)
357		return -ENODEV;
358	if (base->features & DASD_FEATURE_READONLY ||
359	    test_bit(DASD_FLAG_DEVICE_RO, &base->flags)) {
360		rc = -EROFS;
361		goto out_err;
362	}
363	if (bdev_is_partition(bdev)) {
364		pr_warn("%s: The specified DASD is a partition and tracks cannot be released\n",
365			dev_name(&base->cdev->dev));
366		rc = -EINVAL;
367		goto out_err;
368	}
369
370	if (copy_from_user(&rdata, argp, sizeof(rdata))) {
371		rc = -EFAULT;
372		goto out_err;
373	}
374
375	rc = dasd_release_space(base, &rdata);
376
377out_err:
378	dasd_put_device(base);
379
380	return rc;
381}
382
383/*
384 * Swap driver iternal copy relation.
385 */
386static int
387dasd_ioctl_copy_pair_swap(struct block_device *bdev, void __user *argp)
388{
389	struct dasd_copypair_swap_data_t data;
390	struct dasd_device *device;
391	int rc;
392
393	if (!capable(CAP_SYS_ADMIN))
394		return -EACCES;
395
396	device = dasd_device_from_gendisk(bdev->bd_disk);
397	if (!device)
398		return -ENODEV;
399
400	if (copy_from_user(&data, argp, sizeof(struct dasd_copypair_swap_data_t))) {
401		dasd_put_device(device);
402		return -EFAULT;
403	}
404	if (memchr_inv(data.reserved, 0, sizeof(data.reserved))) {
405		pr_warn("%s: Invalid swap data specified\n",
406			dev_name(&device->cdev->dev));
407		dasd_put_device(device);
408		return DASD_COPYPAIRSWAP_INVALID;
409	}
410	if (bdev_is_partition(bdev)) {
411		pr_warn("%s: The specified DASD is a partition and cannot be swapped\n",
412			dev_name(&device->cdev->dev));
413		dasd_put_device(device);
414		return DASD_COPYPAIRSWAP_INVALID;
415	}
416	if (!device->copy) {
417		pr_warn("%s: The specified DASD has no copy pair set up\n",
418			dev_name(&device->cdev->dev));
419		dasd_put_device(device);
420		return -ENODEV;
421	}
422	if (!device->discipline->copy_pair_swap) {
423		dasd_put_device(device);
424		return -EOPNOTSUPP;
425	}
426	rc = device->discipline->copy_pair_swap(device, data.primary,
427						data.secondary);
428	dasd_put_device(device);
429
430	return rc;
431}
432
433#ifdef CONFIG_DASD_PROFILE
434/*
435 * Reset device profile information
436 */
437static int dasd_ioctl_reset_profile(struct dasd_block *block)
438{
439	dasd_profile_reset(&block->profile);
440	return 0;
441}
442
443/*
444 * Return device profile information
445 */
446static int dasd_ioctl_read_profile(struct dasd_block *block, void __user *argp)
447{
448	struct dasd_profile_info_t *data;
449	int rc = 0;
450
451	data = kmalloc(sizeof(*data), GFP_KERNEL);
452	if (!data)
453		return -ENOMEM;
454
455	spin_lock_bh(&block->profile.lock);
456	if (block->profile.data) {
457		data->dasd_io_reqs = block->profile.data->dasd_io_reqs;
458		data->dasd_io_sects = block->profile.data->dasd_io_sects;
459		memcpy(data->dasd_io_secs, block->profile.data->dasd_io_secs,
460		       sizeof(data->dasd_io_secs));
461		memcpy(data->dasd_io_times, block->profile.data->dasd_io_times,
462		       sizeof(data->dasd_io_times));
463		memcpy(data->dasd_io_timps, block->profile.data->dasd_io_timps,
464		       sizeof(data->dasd_io_timps));
465		memcpy(data->dasd_io_time1, block->profile.data->dasd_io_time1,
466		       sizeof(data->dasd_io_time1));
467		memcpy(data->dasd_io_time2, block->profile.data->dasd_io_time2,
468		       sizeof(data->dasd_io_time2));
469		memcpy(data->dasd_io_time2ps,
470		       block->profile.data->dasd_io_time2ps,
471		       sizeof(data->dasd_io_time2ps));
472		memcpy(data->dasd_io_time3, block->profile.data->dasd_io_time3,
473		       sizeof(data->dasd_io_time3));
474		memcpy(data->dasd_io_nr_req,
475		       block->profile.data->dasd_io_nr_req,
476		       sizeof(data->dasd_io_nr_req));
477		spin_unlock_bh(&block->profile.lock);
478	} else {
479		spin_unlock_bh(&block->profile.lock);
480		rc = -EIO;
481		goto out;
482	}
483	if (copy_to_user(argp, data, sizeof(*data)))
484		rc = -EFAULT;
485out:
486	kfree(data);
487	return rc;
488}
489#else
490static int dasd_ioctl_reset_profile(struct dasd_block *block)
491{
492	return -ENOTTY;
493}
494
495static int dasd_ioctl_read_profile(struct dasd_block *block, void __user *argp)
496{
497	return -ENOTTY;
498}
499#endif
500
501/*
502 * Return dasd information. Used for BIODASDINFO and BIODASDINFO2.
503 */
504static int __dasd_ioctl_information(struct dasd_block *block,
505		struct dasd_information2_t *dasd_info)
506{
507	struct subchannel_id sch_id;
508	struct ccw_dev_id dev_id;
509	struct dasd_device *base;
510	struct ccw_device *cdev;
511	struct list_head *l;
512	unsigned long flags;
513	int rc;
514
515	base = block->base;
516	if (!base->discipline || !base->discipline->fill_info)
517		return -EINVAL;
518
519	rc = base->discipline->fill_info(base, dasd_info);
520	if (rc)
521		return rc;
522
523	cdev = base->cdev;
524	ccw_device_get_id(cdev, &dev_id);
525	ccw_device_get_schid(cdev, &sch_id);
526
527	dasd_info->devno = dev_id.devno;
528	dasd_info->schid = sch_id.sch_no;
529	dasd_info->cu_type = cdev->id.cu_type;
530	dasd_info->cu_model = cdev->id.cu_model;
531	dasd_info->dev_type = cdev->id.dev_type;
532	dasd_info->dev_model = cdev->id.dev_model;
533	dasd_info->status = base->state;
534	/*
535	 * The open_count is increased for every opener, that includes
536	 * the blkdev_get in dasd_scan_partitions.
537	 * This must be hidden from user-space.
538	 */
539	dasd_info->open_count = atomic_read(&block->open_count);
540	if (!block->bdev)
541		dasd_info->open_count++;
542
543	/*
544	 * check if device is really formatted
545	 * LDL / CDL was returned by 'fill_info'
546	 */
547	if ((base->state < DASD_STATE_READY) ||
548	    (dasd_check_blocksize(block->bp_block)))
549		dasd_info->format = DASD_FORMAT_NONE;
550
551	dasd_info->features |=
552		((base->features & DASD_FEATURE_READONLY) != 0);
553
554	memcpy(dasd_info->type, base->discipline->name, 4);
555
556	spin_lock_irqsave(get_ccwdev_lock(base->cdev), flags);
557	list_for_each(l, &base->ccw_queue)
558		dasd_info->chanq_len++;
559	spin_unlock_irqrestore(get_ccwdev_lock(base->cdev), flags);
560	return 0;
561}
562
563static int dasd_ioctl_information(struct dasd_block *block, void __user *argp,
564		size_t copy_size)
565{
566	struct dasd_information2_t *dasd_info;
567	int error;
568
569	dasd_info = kzalloc(sizeof(*dasd_info), GFP_KERNEL);
570	if (!dasd_info)
571		return -ENOMEM;
572
573	error = __dasd_ioctl_information(block, dasd_info);
574	if (!error && copy_to_user(argp, dasd_info, copy_size))
575		error = -EFAULT;
576	kfree(dasd_info);
577	return error;
578}
579
580/*
581 * Set read only
582 */
583int dasd_set_read_only(struct block_device *bdev, bool ro)
584{
585	struct dasd_device *base;
586	int rc;
587
588	/* do not manipulate hardware state for partitions */
589	if (bdev_is_partition(bdev))
590		return 0;
591
592	base = dasd_device_from_gendisk(bdev->bd_disk);
593	if (!base)
594		return -ENODEV;
595	if (!ro && test_bit(DASD_FLAG_DEVICE_RO, &base->flags))
596		rc = -EROFS;
597	else
598		rc = dasd_set_feature(base->cdev, DASD_FEATURE_READONLY, ro);
599	dasd_put_device(base);
600	return rc;
601}
602
603static int dasd_ioctl_readall_cmb(struct dasd_block *block, unsigned int cmd,
604				  struct cmbdata __user *argp)
605{
606	size_t size = _IOC_SIZE(cmd);
607	struct cmbdata data;
608	int ret;
609
610	ret = cmf_readall(block->base->cdev, &data);
611	if (!ret && copy_to_user(argp, &data, min(size, sizeof(*argp))))
612		return -EFAULT;
613	return ret;
614}
615
616int dasd_ioctl(struct block_device *bdev, blk_mode_t mode,
617	       unsigned int cmd, unsigned long arg)
618{
619	struct dasd_block *block;
620	struct dasd_device *base;
621	void __user *argp;
622	int rc;
623
624	if (is_compat_task())
625		argp = compat_ptr(arg);
626	else
627		argp = (void __user *)arg;
628
629	if ((_IOC_DIR(cmd) != _IOC_NONE) && !arg)
630		return -EINVAL;
631
632	base = dasd_device_from_gendisk(bdev->bd_disk);
633	if (!base)
634		return -ENODEV;
635	block = base->block;
636	rc = 0;
637	switch (cmd) {
638	case BIODASDDISABLE:
639		rc = dasd_ioctl_disable(bdev);
640		break;
641	case BIODASDENABLE:
642		rc = dasd_ioctl_enable(bdev);
643		break;
644	case BIODASDQUIESCE:
645		rc = dasd_ioctl_quiesce(block);
646		break;
647	case BIODASDRESUME:
648		rc = dasd_ioctl_resume(block);
649		break;
650	case BIODASDABORTIO:
651		rc = dasd_ioctl_abortio(block);
652		break;
653	case BIODASDALLOWIO:
654		rc = dasd_ioctl_allowio(block);
655		break;
656	case BIODASDFMT:
657		rc = dasd_ioctl_format(bdev, argp);
658		break;
659	case BIODASDCHECKFMT:
660		rc = dasd_ioctl_check_format(bdev, argp);
661		break;
662	case BIODASDINFO:
663		rc = dasd_ioctl_information(block, argp,
664				sizeof(struct dasd_information_t));
665		break;
666	case BIODASDINFO2:
667		rc = dasd_ioctl_information(block, argp,
668				sizeof(struct dasd_information2_t));
669		break;
670	case BIODASDPRRD:
671		rc = dasd_ioctl_read_profile(block, argp);
672		break;
673	case BIODASDPRRST:
674		rc = dasd_ioctl_reset_profile(block);
675		break;
676	case DASDAPIVER:
677		rc = dasd_ioctl_api_version(argp);
678		break;
679	case BIODASDCMFENABLE:
680		rc = enable_cmf(base->cdev);
681		break;
682	case BIODASDCMFDISABLE:
683		rc = disable_cmf(base->cdev);
684		break;
685	case BIODASDREADALLCMB:
686		rc = dasd_ioctl_readall_cmb(block, cmd, argp);
687		break;
688	case BIODASDRAS:
689		rc = dasd_ioctl_release_space(bdev, argp);
690		break;
691	case BIODASDCOPYPAIRSWAP:
692		rc = dasd_ioctl_copy_pair_swap(bdev, argp);
693		break;
694	default:
695		/* if the discipline has an ioctl method try it. */
696		rc = -ENOTTY;
697		if (base->discipline->ioctl)
698			rc = base->discipline->ioctl(block, cmd, argp);
699	}
700	dasd_put_device(base);
701	return rc;
702}
703
704
705/**
706 * dasd_biodasdinfo() - fill out the dasd information structure
707 * @disk: [in] pointer to gendisk structure that references a DASD
708 * @info: [out] pointer to the dasd_information2_t structure
709 *
710 * Provide access to DASD specific information.
711 * The gendisk structure is checked if it belongs to the DASD driver by
712 * comparing the gendisk->fops pointer.
713 * If it does not belong to the DASD driver -EINVAL is returned.
714 * Otherwise the provided dasd_information2_t structure is filled out.
715 *
716 * Returns:
717 *   %0 on success and a negative error value on failure.
718 */
719int dasd_biodasdinfo(struct gendisk *disk, struct dasd_information2_t *info)
720{
721	struct dasd_device *base;
722	int error;
723
724	if (disk->fops != &dasd_device_operations)
725		return -EINVAL;
726
727	base = dasd_device_from_gendisk(disk);
728	if (!base)
729		return -ENODEV;
730	error = __dasd_ioctl_information(base->block, info);
731	dasd_put_device(base);
732	return error;
733}
734/* export that symbol_get in partition detection is possible */
735EXPORT_SYMBOL_GPL(dasd_biodasdinfo);
736