xref: /linux/drivers/s390/block/dasd_ioctl.c (revision e9e8bcb8178e197d889ec31e79fa1ddc1732c8f9)
1 /*
2  * File...........: linux/drivers/s390/block/dasd_ioctl.c
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  * (C) IBM Corporation, IBM Deutschland Entwicklung GmbH, 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/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/cmb.h>
23 #include <asm/uaccess.h>
24 
25 /* This is ugly... */
26 #define PRINTK_HEADER "dasd_ioctl:"
27 
28 #include "dasd_int.h"
29 
30 
31 static int
32 dasd_ioctl_api_version(void __user *argp)
33 {
34 	int ver = DASD_API_VERSION;
35 	return put_user(ver, (int __user *)argp);
36 }
37 
38 /*
39  * Enable device.
40  * used by dasdfmt after BIODASDDISABLE to retrigger blocksize detection
41  */
42 static int
43 dasd_ioctl_enable(struct block_device *bdev)
44 {
45 	struct dasd_device *base;
46 
47 	if (!capable(CAP_SYS_ADMIN))
48 		return -EACCES;
49 
50 	base = dasd_device_from_gendisk(bdev->bd_disk);
51 	if (!base)
52 		return -ENODEV;
53 
54 	dasd_enable_device(base);
55 	/* Formatting the dasd device can change the capacity. */
56 	mutex_lock(&bdev->bd_mutex);
57 	i_size_write(bdev->bd_inode,
58 		     (loff_t)get_capacity(base->block->gdp) << 9);
59 	mutex_unlock(&bdev->bd_mutex);
60 	dasd_put_device(base);
61 	return 0;
62 }
63 
64 /*
65  * Disable device.
66  * Used by dasdfmt. Disable I/O operations but allow ioctls.
67  */
68 static int
69 dasd_ioctl_disable(struct block_device *bdev)
70 {
71 	struct dasd_device *base;
72 
73 	if (!capable(CAP_SYS_ADMIN))
74 		return -EACCES;
75 
76 	base = dasd_device_from_gendisk(bdev->bd_disk);
77 	if (!base)
78 		return -ENODEV;
79 	/*
80 	 * Man this is sick. We don't do a real disable but only downgrade
81 	 * the device to DASD_STATE_BASIC. The reason is that dasdfmt uses
82 	 * BIODASDDISABLE to disable accesses to the device via the block
83 	 * device layer but it still wants to do i/o on the device by
84 	 * using the BIODASDFMT ioctl. Therefore the correct state for the
85 	 * device is DASD_STATE_BASIC that allows to do basic i/o.
86 	 */
87 	dasd_set_target_state(base, DASD_STATE_BASIC);
88 	/*
89 	 * Set i_size to zero, since read, write, etc. check against this
90 	 * value.
91 	 */
92 	mutex_lock(&bdev->bd_mutex);
93 	i_size_write(bdev->bd_inode, 0);
94 	mutex_unlock(&bdev->bd_mutex);
95 	dasd_put_device(base);
96 	return 0;
97 }
98 
99 /*
100  * Quiesce device.
101  */
102 static int dasd_ioctl_quiesce(struct dasd_block *block)
103 {
104 	unsigned long flags;
105 	struct dasd_device *base;
106 
107 	base = block->base;
108 	if (!capable (CAP_SYS_ADMIN))
109 		return -EACCES;
110 
111 	pr_info("%s: The DASD has been put in the quiesce "
112 		"state\n", dev_name(&base->cdev->dev));
113 	spin_lock_irqsave(get_ccwdev_lock(base->cdev), flags);
114 	dasd_device_set_stop_bits(base, DASD_STOPPED_QUIESCE);
115 	spin_unlock_irqrestore(get_ccwdev_lock(base->cdev), flags);
116 	return 0;
117 }
118 
119 
120 /*
121  * Resume device.
122  */
123 static int dasd_ioctl_resume(struct dasd_block *block)
124 {
125 	unsigned long flags;
126 	struct dasd_device *base;
127 
128 	base = block->base;
129 	if (!capable (CAP_SYS_ADMIN))
130 		return -EACCES;
131 
132 	pr_info("%s: I/O operations have been resumed "
133 		"on the DASD\n", dev_name(&base->cdev->dev));
134 	spin_lock_irqsave(get_ccwdev_lock(base->cdev), flags);
135 	dasd_device_remove_stop_bits(base, DASD_STOPPED_QUIESCE);
136 	spin_unlock_irqrestore(get_ccwdev_lock(base->cdev), flags);
137 
138 	dasd_schedule_block_bh(block);
139 	return 0;
140 }
141 
142 /*
143  * performs formatting of _device_ according to _fdata_
144  * Note: The discipline's format_function is assumed to deliver formatting
145  * commands to format a single unit of the device. In terms of the ECKD
146  * devices this means CCWs are generated to format a single track.
147  */
148 static int dasd_format(struct dasd_block *block, struct format_data_t *fdata)
149 {
150 	struct dasd_ccw_req *cqr;
151 	struct dasd_device *base;
152 	int rc;
153 
154 	base = block->base;
155 	if (base->discipline->format_device == NULL)
156 		return -EPERM;
157 
158 	if (base->state != DASD_STATE_BASIC) {
159 		pr_warning("%s: The DASD cannot be formatted while it is "
160 			   "enabled\n",  dev_name(&base->cdev->dev));
161 		return -EBUSY;
162 	}
163 
164 	DBF_DEV_EVENT(DBF_NOTICE, base,
165 		      "formatting units %u to %u (%u B blocks) flags %u",
166 		      fdata->start_unit,
167 		      fdata->stop_unit, fdata->blksize, fdata->intensity);
168 
169 	/* Since dasdfmt keeps the device open after it was disabled,
170 	 * there still exists an inode for this device.
171 	 * We must update i_blkbits, otherwise we might get errors when
172 	 * enabling the device later.
173 	 */
174 	if (fdata->start_unit == 0) {
175 		struct block_device *bdev = bdget_disk(block->gdp, 0);
176 		bdev->bd_inode->i_blkbits = blksize_bits(fdata->blksize);
177 		bdput(bdev);
178 	}
179 
180 	while (fdata->start_unit <= fdata->stop_unit) {
181 		cqr = base->discipline->format_device(base, fdata);
182 		if (IS_ERR(cqr))
183 			return PTR_ERR(cqr);
184 		rc = dasd_sleep_on_interruptible(cqr);
185 		dasd_sfree_request(cqr, cqr->memdev);
186 		if (rc) {
187 			if (rc != -ERESTARTSYS)
188 				pr_err("%s: Formatting unit %d failed with "
189 				       "rc=%d\n", dev_name(&base->cdev->dev),
190 				       fdata->start_unit, rc);
191 			return rc;
192 		}
193 		fdata->start_unit++;
194 	}
195 	return 0;
196 }
197 
198 /*
199  * Format device.
200  */
201 static int
202 dasd_ioctl_format(struct block_device *bdev, void __user *argp)
203 {
204 	struct dasd_device *base;
205 	struct format_data_t fdata;
206 	int rc;
207 
208 	if (!capable(CAP_SYS_ADMIN))
209 		return -EACCES;
210 	if (!argp)
211 		return -EINVAL;
212 	base = dasd_device_from_gendisk(bdev->bd_disk);
213 	if (!base)
214 		return -ENODEV;
215 	if (base->features & DASD_FEATURE_READONLY ||
216 	    test_bit(DASD_FLAG_DEVICE_RO, &base->flags)) {
217 		dasd_put_device(base);
218 		return -EROFS;
219 	}
220 	if (copy_from_user(&fdata, argp, sizeof(struct format_data_t))) {
221 		dasd_put_device(base);
222 		return -EFAULT;
223 	}
224 	if (bdev != bdev->bd_contains) {
225 		pr_warning("%s: The specified DASD is a partition and cannot "
226 			   "be formatted\n",
227 			   dev_name(&base->cdev->dev));
228 		dasd_put_device(base);
229 		return -EINVAL;
230 	}
231 	rc = dasd_format(base->block, &fdata);
232 	dasd_put_device(base);
233 	return rc;
234 }
235 
236 #ifdef CONFIG_DASD_PROFILE
237 /*
238  * Reset device profile information
239  */
240 static int dasd_ioctl_reset_profile(struct dasd_block *block)
241 {
242 	memset(&block->profile, 0, sizeof(struct dasd_profile_info_t));
243 	return 0;
244 }
245 
246 /*
247  * Return device profile information
248  */
249 static int dasd_ioctl_read_profile(struct dasd_block *block, void __user *argp)
250 {
251 	if (dasd_profile_level == DASD_PROFILE_OFF)
252 		return -EIO;
253 	if (copy_to_user(argp, &block->profile,
254 			 sizeof(struct dasd_profile_info_t)))
255 		return -EFAULT;
256 	return 0;
257 }
258 #else
259 static int dasd_ioctl_reset_profile(struct dasd_block *block)
260 {
261 	return -ENOSYS;
262 }
263 
264 static int dasd_ioctl_read_profile(struct dasd_block *block, void __user *argp)
265 {
266 	return -ENOSYS;
267 }
268 #endif
269 
270 /*
271  * Return dasd information. Used for BIODASDINFO and BIODASDINFO2.
272  */
273 static int dasd_ioctl_information(struct dasd_block *block,
274 				  unsigned int cmd, void __user *argp)
275 {
276 	struct dasd_information2_t *dasd_info;
277 	unsigned long flags;
278 	int rc;
279 	struct dasd_device *base;
280 	struct ccw_device *cdev;
281 	struct ccw_dev_id dev_id;
282 
283 	base = block->base;
284 	if (!base->discipline || !base->discipline->fill_info)
285 		return -EINVAL;
286 
287 	dasd_info = kzalloc(sizeof(struct dasd_information2_t), GFP_KERNEL);
288 	if (dasd_info == NULL)
289 		return -ENOMEM;
290 
291 	rc = base->discipline->fill_info(base, dasd_info);
292 	if (rc) {
293 		kfree(dasd_info);
294 		return rc;
295 	}
296 
297 	cdev = base->cdev;
298 	ccw_device_get_id(cdev, &dev_id);
299 
300 	dasd_info->devno = dev_id.devno;
301 	dasd_info->schid = _ccw_device_get_subchannel_number(base->cdev);
302 	dasd_info->cu_type = cdev->id.cu_type;
303 	dasd_info->cu_model = cdev->id.cu_model;
304 	dasd_info->dev_type = cdev->id.dev_type;
305 	dasd_info->dev_model = cdev->id.dev_model;
306 	dasd_info->status = base->state;
307 	/*
308 	 * The open_count is increased for every opener, that includes
309 	 * the blkdev_get in dasd_scan_partitions.
310 	 * This must be hidden from user-space.
311 	 */
312 	dasd_info->open_count = atomic_read(&block->open_count);
313 	if (!block->bdev)
314 		dasd_info->open_count++;
315 
316 	/*
317 	 * check if device is really formatted
318 	 * LDL / CDL was returned by 'fill_info'
319 	 */
320 	if ((base->state < DASD_STATE_READY) ||
321 	    (dasd_check_blocksize(block->bp_block)))
322 		dasd_info->format = DASD_FORMAT_NONE;
323 
324 	dasd_info->features |=
325 		((base->features & DASD_FEATURE_READONLY) != 0);
326 
327 	memcpy(dasd_info->type, base->discipline->name, 4);
328 
329 	if (block->request_queue->request_fn) {
330 		struct list_head *l;
331 #ifdef DASD_EXTENDED_PROFILING
332 		{
333 			struct list_head *l;
334 			spin_lock_irqsave(&block->lock, flags);
335 			list_for_each(l, &block->request_queue->queue_head)
336 				dasd_info->req_queue_len++;
337 			spin_unlock_irqrestore(&block->lock, flags);
338 		}
339 #endif				/* DASD_EXTENDED_PROFILING */
340 		spin_lock_irqsave(get_ccwdev_lock(base->cdev), flags);
341 		list_for_each(l, &base->ccw_queue)
342 			dasd_info->chanq_len++;
343 		spin_unlock_irqrestore(get_ccwdev_lock(base->cdev),
344 				       flags);
345 	}
346 
347 	rc = 0;
348 	if (copy_to_user(argp, dasd_info,
349 			 ((cmd == (unsigned int) BIODASDINFO2) ?
350 			  sizeof(struct dasd_information2_t) :
351 			  sizeof(struct dasd_information_t))))
352 		rc = -EFAULT;
353 	kfree(dasd_info);
354 	return rc;
355 }
356 
357 /*
358  * Set read only
359  */
360 static int
361 dasd_ioctl_set_ro(struct block_device *bdev, void __user *argp)
362 {
363 	struct dasd_device *base;
364 	int intval, rc;
365 
366 	if (!capable(CAP_SYS_ADMIN))
367 		return -EACCES;
368 	if (bdev != bdev->bd_contains)
369 		// ro setting is not allowed for partitions
370 		return -EINVAL;
371 	if (get_user(intval, (int __user *)argp))
372 		return -EFAULT;
373 	base = dasd_device_from_gendisk(bdev->bd_disk);
374 	if (!base)
375 		return -ENODEV;
376 	if (!intval && test_bit(DASD_FLAG_DEVICE_RO, &base->flags)) {
377 		dasd_put_device(base);
378 		return -EROFS;
379 	}
380 	set_disk_ro(bdev->bd_disk, intval);
381 	rc = dasd_set_feature(base->cdev, DASD_FEATURE_READONLY, intval);
382 	dasd_put_device(base);
383 	return rc;
384 }
385 
386 static int dasd_ioctl_readall_cmb(struct dasd_block *block, unsigned int cmd,
387 				  struct cmbdata __user *argp)
388 {
389 	size_t size = _IOC_SIZE(cmd);
390 	struct cmbdata data;
391 	int ret;
392 
393 	ret = cmf_readall(block->base->cdev, &data);
394 	if (!ret && copy_to_user(argp, &data, min(size, sizeof(*argp))))
395 		return -EFAULT;
396 	return ret;
397 }
398 
399 int dasd_ioctl(struct block_device *bdev, fmode_t mode,
400 	       unsigned int cmd, unsigned long arg)
401 {
402 	struct dasd_block *block;
403 	struct dasd_device *base;
404 	void __user *argp;
405 	int rc;
406 
407 	if (is_compat_task())
408 		argp = compat_ptr(arg);
409 	else
410 		argp = (void __user *)arg;
411 
412 	if ((_IOC_DIR(cmd) != _IOC_NONE) && !arg) {
413 		PRINT_DEBUG("empty data ptr");
414 		return -EINVAL;
415 	}
416 
417 	base = dasd_device_from_gendisk(bdev->bd_disk);
418 	if (!base)
419 		return -ENODEV;
420 	block = base->block;
421 	rc = 0;
422 	switch (cmd) {
423 	case BIODASDDISABLE:
424 		rc = dasd_ioctl_disable(bdev);
425 		break;
426 	case BIODASDENABLE:
427 		rc = dasd_ioctl_enable(bdev);
428 		break;
429 	case BIODASDQUIESCE:
430 		rc = dasd_ioctl_quiesce(block);
431 		break;
432 	case BIODASDRESUME:
433 		rc = dasd_ioctl_resume(block);
434 		break;
435 	case BIODASDFMT:
436 		rc = dasd_ioctl_format(bdev, argp);
437 		break;
438 	case BIODASDINFO:
439 		rc = dasd_ioctl_information(block, cmd, argp);
440 		break;
441 	case BIODASDINFO2:
442 		rc = dasd_ioctl_information(block, cmd, argp);
443 		break;
444 	case BIODASDPRRD:
445 		rc = dasd_ioctl_read_profile(block, argp);
446 		break;
447 	case BIODASDPRRST:
448 		rc = dasd_ioctl_reset_profile(block);
449 		break;
450 	case BLKROSET:
451 		rc = dasd_ioctl_set_ro(bdev, argp);
452 		break;
453 	case DASDAPIVER:
454 		rc = dasd_ioctl_api_version(argp);
455 		break;
456 	case BIODASDCMFENABLE:
457 		rc = enable_cmf(base->cdev);
458 		break;
459 	case BIODASDCMFDISABLE:
460 		rc = disable_cmf(base->cdev);
461 		break;
462 	case BIODASDREADALLCMB:
463 		rc = dasd_ioctl_readall_cmb(block, cmd, argp);
464 		break;
465 	default:
466 		/* if the discipline has an ioctl method try it. */
467 		if (base->discipline->ioctl) {
468 			rc = base->discipline->ioctl(block, cmd, argp);
469 			if (rc == -ENOIOCTLCMD)
470 				rc = -EINVAL;
471 		} else
472 			rc = -EINVAL;
473 	}
474 	dasd_put_device(base);
475 	return rc;
476 }
477