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
32static int
33dasd_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 */
43static int
44dasd_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 */
69static int
70dasd_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 */
103static 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 */
124static 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 */
146static 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 */
182static 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 */
202static int
203dasd_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 */
265static int
266dasd_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 */
304static 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 */
313static 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;
352out:
353	kfree(data);
354	return rc;
355}
356#else
357static int dasd_ioctl_reset_profile(struct dasd_block *block)
358{
359	return -ENOTTY;
360}
361
362static 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 */
371static 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 */
460static int
461dasd_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
486static 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
499int 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