xref: /openbmc/linux/drivers/s390/block/dasd_ioctl.c (revision 39b6f3aa)
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  * performs formatting of _device_ according to _fdata_
145  * Note: The discipline's format_function is assumed to deliver formatting
146  * commands to format multiple units of the device. In terms of the ECKD
147  * devices this means CCWs are generated to format multiple tracks.
148  */
149 static int
150 dasd_format(struct dasd_block *block, struct format_data_t *fdata)
151 {
152 	struct dasd_device *base;
153 	int rc;
154 
155 	base = block->base;
156 	if (base->discipline->format_device == NULL)
157 		return -EPERM;
158 
159 	if (base->state != DASD_STATE_BASIC) {
160 		pr_warn("%s: The DASD cannot be formatted while it is enabled\n",
161 			dev_name(&base->cdev->dev));
162 		return -EBUSY;
163 	}
164 
165 	DBF_DEV_EVENT(DBF_NOTICE, base,
166 		      "formatting units %u to %u (%u B blocks) flags %u",
167 		      fdata->start_unit,
168 		      fdata->stop_unit, fdata->blksize, fdata->intensity);
169 
170 	/* Since dasdfmt keeps the device open after it was disabled,
171 	 * there still exists an inode for this device.
172 	 * We must update i_blkbits, otherwise we might get errors when
173 	 * enabling the device later.
174 	 */
175 	if (fdata->start_unit == 0) {
176 		struct block_device *bdev = bdget_disk(block->gdp, 0);
177 		bdev->bd_inode->i_blkbits = blksize_bits(fdata->blksize);
178 		bdput(bdev);
179 	}
180 
181 	rc = base->discipline->format_device(base, fdata);
182 	if (rc)
183 		return rc;
184 
185 	return 0;
186 }
187 
188 /*
189  * Format device.
190  */
191 static int
192 dasd_ioctl_format(struct block_device *bdev, void __user *argp)
193 {
194 	struct dasd_device *base;
195 	struct format_data_t fdata;
196 	int rc;
197 
198 	if (!capable(CAP_SYS_ADMIN))
199 		return -EACCES;
200 	if (!argp)
201 		return -EINVAL;
202 	base = dasd_device_from_gendisk(bdev->bd_disk);
203 	if (!base)
204 		return -ENODEV;
205 	if (base->features & DASD_FEATURE_READONLY ||
206 	    test_bit(DASD_FLAG_DEVICE_RO, &base->flags)) {
207 		dasd_put_device(base);
208 		return -EROFS;
209 	}
210 	if (copy_from_user(&fdata, argp, sizeof(struct format_data_t))) {
211 		dasd_put_device(base);
212 		return -EFAULT;
213 	}
214 	if (bdev != bdev->bd_contains) {
215 		pr_warning("%s: The specified DASD is a partition and cannot "
216 			   "be formatted\n",
217 			   dev_name(&base->cdev->dev));
218 		dasd_put_device(base);
219 		return -EINVAL;
220 	}
221 	rc = dasd_format(base->block, &fdata);
222 	dasd_put_device(base);
223 	return rc;
224 }
225 
226 #ifdef CONFIG_DASD_PROFILE
227 /*
228  * Reset device profile information
229  */
230 static int dasd_ioctl_reset_profile(struct dasd_block *block)
231 {
232 	dasd_profile_reset(&block->profile);
233 	return 0;
234 }
235 
236 /*
237  * Return device profile information
238  */
239 static int dasd_ioctl_read_profile(struct dasd_block *block, void __user *argp)
240 {
241 	struct dasd_profile_info_t *data;
242 	int rc = 0;
243 
244 	data = kmalloc(sizeof(*data), GFP_KERNEL);
245 	if (!data)
246 		return -ENOMEM;
247 
248 	spin_lock_bh(&block->profile.lock);
249 	if (block->profile.data) {
250 		data->dasd_io_reqs = block->profile.data->dasd_io_reqs;
251 		data->dasd_io_sects = block->profile.data->dasd_io_sects;
252 		memcpy(data->dasd_io_secs, block->profile.data->dasd_io_secs,
253 		       sizeof(data->dasd_io_secs));
254 		memcpy(data->dasd_io_times, block->profile.data->dasd_io_times,
255 		       sizeof(data->dasd_io_times));
256 		memcpy(data->dasd_io_timps, block->profile.data->dasd_io_timps,
257 		       sizeof(data->dasd_io_timps));
258 		memcpy(data->dasd_io_time1, block->profile.data->dasd_io_time1,
259 		       sizeof(data->dasd_io_time1));
260 		memcpy(data->dasd_io_time2, block->profile.data->dasd_io_time2,
261 		       sizeof(data->dasd_io_time2));
262 		memcpy(data->dasd_io_time2ps,
263 		       block->profile.data->dasd_io_time2ps,
264 		       sizeof(data->dasd_io_time2ps));
265 		memcpy(data->dasd_io_time3, block->profile.data->dasd_io_time3,
266 		       sizeof(data->dasd_io_time3));
267 		memcpy(data->dasd_io_nr_req,
268 		       block->profile.data->dasd_io_nr_req,
269 		       sizeof(data->dasd_io_nr_req));
270 		spin_unlock_bh(&block->profile.lock);
271 	} else {
272 		spin_unlock_bh(&block->profile.lock);
273 		rc = -EIO;
274 		goto out;
275 	}
276 	if (copy_to_user(argp, data, sizeof(*data)))
277 		rc = -EFAULT;
278 out:
279 	kfree(data);
280 	return rc;
281 }
282 #else
283 static int dasd_ioctl_reset_profile(struct dasd_block *block)
284 {
285 	return -ENOTTY;
286 }
287 
288 static int dasd_ioctl_read_profile(struct dasd_block *block, void __user *argp)
289 {
290 	return -ENOTTY;
291 }
292 #endif
293 
294 /*
295  * Return dasd information. Used for BIODASDINFO and BIODASDINFO2.
296  */
297 static int dasd_ioctl_information(struct dasd_block *block,
298 				  unsigned int cmd, void __user *argp)
299 {
300 	struct dasd_information2_t *dasd_info;
301 	struct subchannel_id sch_id;
302 	struct ccw_dev_id dev_id;
303 	struct dasd_device *base;
304 	struct ccw_device *cdev;
305 	unsigned long flags;
306 	int rc;
307 
308 	base = block->base;
309 	if (!base->discipline || !base->discipline->fill_info)
310 		return -EINVAL;
311 
312 	dasd_info = kzalloc(sizeof(struct dasd_information2_t), GFP_KERNEL);
313 	if (dasd_info == NULL)
314 		return -ENOMEM;
315 
316 	rc = base->discipline->fill_info(base, dasd_info);
317 	if (rc) {
318 		kfree(dasd_info);
319 		return rc;
320 	}
321 
322 	cdev = base->cdev;
323 	ccw_device_get_id(cdev, &dev_id);
324 	ccw_device_get_schid(cdev, &sch_id);
325 
326 	dasd_info->devno = dev_id.devno;
327 	dasd_info->schid = sch_id.sch_no;
328 	dasd_info->cu_type = cdev->id.cu_type;
329 	dasd_info->cu_model = cdev->id.cu_model;
330 	dasd_info->dev_type = cdev->id.dev_type;
331 	dasd_info->dev_model = cdev->id.dev_model;
332 	dasd_info->status = base->state;
333 	/*
334 	 * The open_count is increased for every opener, that includes
335 	 * the blkdev_get in dasd_scan_partitions.
336 	 * This must be hidden from user-space.
337 	 */
338 	dasd_info->open_count = atomic_read(&block->open_count);
339 	if (!block->bdev)
340 		dasd_info->open_count++;
341 
342 	/*
343 	 * check if device is really formatted
344 	 * LDL / CDL was returned by 'fill_info'
345 	 */
346 	if ((base->state < DASD_STATE_READY) ||
347 	    (dasd_check_blocksize(block->bp_block)))
348 		dasd_info->format = DASD_FORMAT_NONE;
349 
350 	dasd_info->features |=
351 		((base->features & DASD_FEATURE_READONLY) != 0);
352 
353 	memcpy(dasd_info->type, base->discipline->name, 4);
354 
355 	if (block->request_queue->request_fn) {
356 		struct list_head *l;
357 #ifdef DASD_EXTENDED_PROFILING
358 		{
359 			struct list_head *l;
360 			spin_lock_irqsave(&block->lock, flags);
361 			list_for_each(l, &block->request_queue->queue_head)
362 				dasd_info->req_queue_len++;
363 			spin_unlock_irqrestore(&block->lock, flags);
364 		}
365 #endif				/* DASD_EXTENDED_PROFILING */
366 		spin_lock_irqsave(get_ccwdev_lock(base->cdev), flags);
367 		list_for_each(l, &base->ccw_queue)
368 			dasd_info->chanq_len++;
369 		spin_unlock_irqrestore(get_ccwdev_lock(base->cdev),
370 				       flags);
371 	}
372 
373 	rc = 0;
374 	if (copy_to_user(argp, dasd_info,
375 			 ((cmd == (unsigned int) BIODASDINFO2) ?
376 			  sizeof(struct dasd_information2_t) :
377 			  sizeof(struct dasd_information_t))))
378 		rc = -EFAULT;
379 	kfree(dasd_info);
380 	return rc;
381 }
382 
383 /*
384  * Set read only
385  */
386 static int
387 dasd_ioctl_set_ro(struct block_device *bdev, void __user *argp)
388 {
389 	struct dasd_device *base;
390 	int intval, rc;
391 
392 	if (!capable(CAP_SYS_ADMIN))
393 		return -EACCES;
394 	if (bdev != bdev->bd_contains)
395 		// ro setting is not allowed for partitions
396 		return -EINVAL;
397 	if (get_user(intval, (int __user *)argp))
398 		return -EFAULT;
399 	base = dasd_device_from_gendisk(bdev->bd_disk);
400 	if (!base)
401 		return -ENODEV;
402 	if (!intval && test_bit(DASD_FLAG_DEVICE_RO, &base->flags)) {
403 		dasd_put_device(base);
404 		return -EROFS;
405 	}
406 	set_disk_ro(bdev->bd_disk, intval);
407 	rc = dasd_set_feature(base->cdev, DASD_FEATURE_READONLY, intval);
408 	dasd_put_device(base);
409 	return rc;
410 }
411 
412 static int dasd_ioctl_readall_cmb(struct dasd_block *block, unsigned int cmd,
413 				  struct cmbdata __user *argp)
414 {
415 	size_t size = _IOC_SIZE(cmd);
416 	struct cmbdata data;
417 	int ret;
418 
419 	ret = cmf_readall(block->base->cdev, &data);
420 	if (!ret && copy_to_user(argp, &data, min(size, sizeof(*argp))))
421 		return -EFAULT;
422 	return ret;
423 }
424 
425 int dasd_ioctl(struct block_device *bdev, fmode_t mode,
426 	       unsigned int cmd, unsigned long arg)
427 {
428 	struct dasd_block *block;
429 	struct dasd_device *base;
430 	void __user *argp;
431 	int rc;
432 
433 	if (is_compat_task())
434 		argp = compat_ptr(arg);
435 	else
436 		argp = (void __user *)arg;
437 
438 	if ((_IOC_DIR(cmd) != _IOC_NONE) && !arg) {
439 		PRINT_DEBUG("empty data ptr");
440 		return -EINVAL;
441 	}
442 
443 	base = dasd_device_from_gendisk(bdev->bd_disk);
444 	if (!base)
445 		return -ENODEV;
446 	block = base->block;
447 	rc = 0;
448 	switch (cmd) {
449 	case BIODASDDISABLE:
450 		rc = dasd_ioctl_disable(bdev);
451 		break;
452 	case BIODASDENABLE:
453 		rc = dasd_ioctl_enable(bdev);
454 		break;
455 	case BIODASDQUIESCE:
456 		rc = dasd_ioctl_quiesce(block);
457 		break;
458 	case BIODASDRESUME:
459 		rc = dasd_ioctl_resume(block);
460 		break;
461 	case BIODASDFMT:
462 		rc = dasd_ioctl_format(bdev, argp);
463 		break;
464 	case BIODASDINFO:
465 		rc = dasd_ioctl_information(block, cmd, argp);
466 		break;
467 	case BIODASDINFO2:
468 		rc = dasd_ioctl_information(block, cmd, argp);
469 		break;
470 	case BIODASDPRRD:
471 		rc = dasd_ioctl_read_profile(block, argp);
472 		break;
473 	case BIODASDPRRST:
474 		rc = dasd_ioctl_reset_profile(block);
475 		break;
476 	case BLKROSET:
477 		rc = dasd_ioctl_set_ro(bdev, argp);
478 		break;
479 	case DASDAPIVER:
480 		rc = dasd_ioctl_api_version(argp);
481 		break;
482 	case BIODASDCMFENABLE:
483 		rc = enable_cmf(base->cdev);
484 		break;
485 	case BIODASDCMFDISABLE:
486 		rc = disable_cmf(base->cdev);
487 		break;
488 	case BIODASDREADALLCMB:
489 		rc = dasd_ioctl_readall_cmb(block, cmd, argp);
490 		break;
491 	default:
492 		/* if the discipline has an ioctl method try it. */
493 		rc = -ENOTTY;
494 		if (base->discipline->ioctl)
495 			rc = base->discipline->ioctl(block, cmd, argp);
496 	}
497 	dasd_put_device(base);
498 	return rc;
499 }
500