xref: /openbmc/linux/drivers/s390/block/dasd_ioctl.c (revision b6dcefde)
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/smp_lock.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_block *block = bdev->bd_disk->private_data;
46 
47 	if (!capable(CAP_SYS_ADMIN))
48 		return -EACCES;
49 
50 	dasd_enable_device(block->base);
51 	/* Formatting the dasd device can change the capacity. */
52 	mutex_lock(&bdev->bd_mutex);
53 	i_size_write(bdev->bd_inode, (loff_t)get_capacity(block->gdp) << 9);
54 	mutex_unlock(&bdev->bd_mutex);
55 	return 0;
56 }
57 
58 /*
59  * Disable device.
60  * Used by dasdfmt. Disable I/O operations but allow ioctls.
61  */
62 static int
63 dasd_ioctl_disable(struct block_device *bdev)
64 {
65 	struct dasd_block *block = bdev->bd_disk->private_data;
66 
67 	if (!capable(CAP_SYS_ADMIN))
68 		return -EACCES;
69 
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(block->base, DASD_STATE_BASIC);
79 	/*
80 	 * Set i_size to zero, since read, write, etc. check against this
81 	 * value.
82 	 */
83 	mutex_lock(&bdev->bd_mutex);
84 	i_size_write(bdev->bd_inode, 0);
85 	mutex_unlock(&bdev->bd_mutex);
86 	return 0;
87 }
88 
89 /*
90  * Quiesce device.
91  */
92 static int dasd_ioctl_quiesce(struct dasd_block *block)
93 {
94 	unsigned long flags;
95 	struct dasd_device *base;
96 
97 	base = block->base;
98 	if (!capable (CAP_SYS_ADMIN))
99 		return -EACCES;
100 
101 	pr_info("%s: The DASD has been put in the quiesce "
102 		"state\n", dev_name(&base->cdev->dev));
103 	spin_lock_irqsave(get_ccwdev_lock(base->cdev), flags);
104 	dasd_device_set_stop_bits(base, DASD_STOPPED_QUIESCE);
105 	spin_unlock_irqrestore(get_ccwdev_lock(base->cdev), flags);
106 	return 0;
107 }
108 
109 
110 /*
111  * Resume device.
112  */
113 static int dasd_ioctl_resume(struct dasd_block *block)
114 {
115 	unsigned long flags;
116 	struct dasd_device *base;
117 
118 	base = block->base;
119 	if (!capable (CAP_SYS_ADMIN))
120 		return -EACCES;
121 
122 	pr_info("%s: I/O operations have been resumed "
123 		"on the DASD\n", dev_name(&base->cdev->dev));
124 	spin_lock_irqsave(get_ccwdev_lock(base->cdev), flags);
125 	dasd_device_remove_stop_bits(base, DASD_STOPPED_QUIESCE);
126 	spin_unlock_irqrestore(get_ccwdev_lock(base->cdev), flags);
127 
128 	dasd_schedule_block_bh(block);
129 	return 0;
130 }
131 
132 /*
133  * performs formatting of _device_ according to _fdata_
134  * Note: The discipline's format_function is assumed to deliver formatting
135  * commands to format a single unit of the device. In terms of the ECKD
136  * devices this means CCWs are generated to format a single track.
137  */
138 static int dasd_format(struct dasd_block *block, struct format_data_t *fdata)
139 {
140 	struct dasd_ccw_req *cqr;
141 	struct dasd_device *base;
142 	int rc;
143 
144 	base = block->base;
145 	if (base->discipline->format_device == NULL)
146 		return -EPERM;
147 
148 	if (base->state != DASD_STATE_BASIC) {
149 		pr_warning("%s: The DASD cannot be formatted while it is "
150 			   "enabled\n",  dev_name(&base->cdev->dev));
151 		return -EBUSY;
152 	}
153 
154 	DBF_DEV_EVENT(DBF_NOTICE, base,
155 		      "formatting units %u to %u (%u B blocks) flags %u",
156 		      fdata->start_unit,
157 		      fdata->stop_unit, fdata->blksize, fdata->intensity);
158 
159 	/* Since dasdfmt keeps the device open after it was disabled,
160 	 * there still exists an inode for this device.
161 	 * We must update i_blkbits, otherwise we might get errors when
162 	 * enabling the device later.
163 	 */
164 	if (fdata->start_unit == 0) {
165 		struct block_device *bdev = bdget_disk(block->gdp, 0);
166 		bdev->bd_inode->i_blkbits = blksize_bits(fdata->blksize);
167 		bdput(bdev);
168 	}
169 
170 	while (fdata->start_unit <= fdata->stop_unit) {
171 		cqr = base->discipline->format_device(base, fdata);
172 		if (IS_ERR(cqr))
173 			return PTR_ERR(cqr);
174 		rc = dasd_sleep_on_interruptible(cqr);
175 		dasd_sfree_request(cqr, cqr->memdev);
176 		if (rc) {
177 			if (rc != -ERESTARTSYS)
178 				pr_err("%s: Formatting unit %d failed with "
179 				       "rc=%d\n", dev_name(&base->cdev->dev),
180 				       fdata->start_unit, rc);
181 			return rc;
182 		}
183 		fdata->start_unit++;
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_block *block = bdev->bd_disk->private_data;
195 	struct format_data_t fdata;
196 
197 	if (!capable(CAP_SYS_ADMIN))
198 		return -EACCES;
199 	if (!argp)
200 		return -EINVAL;
201 
202 	if (block->base->features & DASD_FEATURE_READONLY)
203 		return -EROFS;
204 	if (copy_from_user(&fdata, argp, sizeof(struct format_data_t)))
205 		return -EFAULT;
206 	if (bdev != bdev->bd_contains) {
207 		pr_warning("%s: The specified DASD is a partition and cannot "
208 			   "be formatted\n",
209 			   dev_name(&block->base->cdev->dev));
210 		return -EINVAL;
211 	}
212 	return dasd_format(block, &fdata);
213 }
214 
215 #ifdef CONFIG_DASD_PROFILE
216 /*
217  * Reset device profile information
218  */
219 static int dasd_ioctl_reset_profile(struct dasd_block *block)
220 {
221 	memset(&block->profile, 0, sizeof(struct dasd_profile_info_t));
222 	return 0;
223 }
224 
225 /*
226  * Return device profile information
227  */
228 static int dasd_ioctl_read_profile(struct dasd_block *block, void __user *argp)
229 {
230 	if (dasd_profile_level == DASD_PROFILE_OFF)
231 		return -EIO;
232 	if (copy_to_user(argp, &block->profile,
233 			 sizeof(struct dasd_profile_info_t)))
234 		return -EFAULT;
235 	return 0;
236 }
237 #else
238 static int dasd_ioctl_reset_profile(struct dasd_block *block)
239 {
240 	return -ENOSYS;
241 }
242 
243 static int dasd_ioctl_read_profile(struct dasd_block *block, void __user *argp)
244 {
245 	return -ENOSYS;
246 }
247 #endif
248 
249 /*
250  * Return dasd information. Used for BIODASDINFO and BIODASDINFO2.
251  */
252 static int dasd_ioctl_information(struct dasd_block *block,
253 				  unsigned int cmd, void __user *argp)
254 {
255 	struct dasd_information2_t *dasd_info;
256 	unsigned long flags;
257 	int rc;
258 	struct dasd_device *base;
259 	struct ccw_device *cdev;
260 	struct ccw_dev_id dev_id;
261 
262 	base = block->base;
263 	if (!base->discipline || !base->discipline->fill_info)
264 		return -EINVAL;
265 
266 	dasd_info = kzalloc(sizeof(struct dasd_information2_t), GFP_KERNEL);
267 	if (dasd_info == NULL)
268 		return -ENOMEM;
269 
270 	rc = base->discipline->fill_info(base, dasd_info);
271 	if (rc) {
272 		kfree(dasd_info);
273 		return rc;
274 	}
275 
276 	cdev = base->cdev;
277 	ccw_device_get_id(cdev, &dev_id);
278 
279 	dasd_info->devno = dev_id.devno;
280 	dasd_info->schid = _ccw_device_get_subchannel_number(base->cdev);
281 	dasd_info->cu_type = cdev->id.cu_type;
282 	dasd_info->cu_model = cdev->id.cu_model;
283 	dasd_info->dev_type = cdev->id.dev_type;
284 	dasd_info->dev_model = cdev->id.dev_model;
285 	dasd_info->status = base->state;
286 	/*
287 	 * The open_count is increased for every opener, that includes
288 	 * the blkdev_get in dasd_scan_partitions.
289 	 * This must be hidden from user-space.
290 	 */
291 	dasd_info->open_count = atomic_read(&block->open_count);
292 	if (!block->bdev)
293 		dasd_info->open_count++;
294 
295 	/*
296 	 * check if device is really formatted
297 	 * LDL / CDL was returned by 'fill_info'
298 	 */
299 	if ((base->state < DASD_STATE_READY) ||
300 	    (dasd_check_blocksize(block->bp_block)))
301 		dasd_info->format = DASD_FORMAT_NONE;
302 
303 	dasd_info->features |=
304 		((base->features & DASD_FEATURE_READONLY) != 0);
305 
306 	memcpy(dasd_info->type, base->discipline->name, 4);
307 
308 	if (block->request_queue->request_fn) {
309 		struct list_head *l;
310 #ifdef DASD_EXTENDED_PROFILING
311 		{
312 			struct list_head *l;
313 			spin_lock_irqsave(&block->lock, flags);
314 			list_for_each(l, &block->request_queue->queue_head)
315 				dasd_info->req_queue_len++;
316 			spin_unlock_irqrestore(&block->lock, flags);
317 		}
318 #endif				/* DASD_EXTENDED_PROFILING */
319 		spin_lock_irqsave(get_ccwdev_lock(base->cdev), flags);
320 		list_for_each(l, &base->ccw_queue)
321 			dasd_info->chanq_len++;
322 		spin_unlock_irqrestore(get_ccwdev_lock(base->cdev),
323 				       flags);
324 	}
325 
326 	rc = 0;
327 	if (copy_to_user(argp, dasd_info,
328 			 ((cmd == (unsigned int) BIODASDINFO2) ?
329 			  sizeof(struct dasd_information2_t) :
330 			  sizeof(struct dasd_information_t))))
331 		rc = -EFAULT;
332 	kfree(dasd_info);
333 	return rc;
334 }
335 
336 /*
337  * Set read only
338  */
339 static int
340 dasd_ioctl_set_ro(struct block_device *bdev, void __user *argp)
341 {
342 	struct dasd_block *block =  bdev->bd_disk->private_data;
343 	int intval;
344 
345 	if (!capable(CAP_SYS_ADMIN))
346 		return -EACCES;
347 	if (bdev != bdev->bd_contains)
348 		// ro setting is not allowed for partitions
349 		return -EINVAL;
350 	if (get_user(intval, (int __user *)argp))
351 		return -EFAULT;
352 
353 	set_disk_ro(bdev->bd_disk, intval);
354 	return dasd_set_feature(block->base->cdev, DASD_FEATURE_READONLY, intval);
355 }
356 
357 static int dasd_ioctl_readall_cmb(struct dasd_block *block, unsigned int cmd,
358 				  struct cmbdata __user *argp)
359 {
360 	size_t size = _IOC_SIZE(cmd);
361 	struct cmbdata data;
362 	int ret;
363 
364 	ret = cmf_readall(block->base->cdev, &data);
365 	if (!ret && copy_to_user(argp, &data, min(size, sizeof(*argp))))
366 		return -EFAULT;
367 	return ret;
368 }
369 
370 static int
371 dasd_do_ioctl(struct block_device *bdev, fmode_t mode,
372 	      unsigned int cmd, unsigned long arg)
373 {
374 	struct dasd_block *block = bdev->bd_disk->private_data;
375 	void __user *argp;
376 
377 	if (is_compat_task())
378 		argp = compat_ptr(arg);
379 	else
380 		argp = (void __user *)arg;
381 
382 	if (!block)
383                 return -ENODEV;
384 
385 	if ((_IOC_DIR(cmd) != _IOC_NONE) && !arg) {
386 		PRINT_DEBUG("empty data ptr");
387 		return -EINVAL;
388 	}
389 
390 	switch (cmd) {
391 	case BIODASDDISABLE:
392 		return dasd_ioctl_disable(bdev);
393 	case BIODASDENABLE:
394 		return dasd_ioctl_enable(bdev);
395 	case BIODASDQUIESCE:
396 		return dasd_ioctl_quiesce(block);
397 	case BIODASDRESUME:
398 		return dasd_ioctl_resume(block);
399 	case BIODASDFMT:
400 		return dasd_ioctl_format(bdev, argp);
401 	case BIODASDINFO:
402 		return dasd_ioctl_information(block, cmd, argp);
403 	case BIODASDINFO2:
404 		return dasd_ioctl_information(block, cmd, argp);
405 	case BIODASDPRRD:
406 		return dasd_ioctl_read_profile(block, argp);
407 	case BIODASDPRRST:
408 		return dasd_ioctl_reset_profile(block);
409 	case BLKROSET:
410 		return dasd_ioctl_set_ro(bdev, argp);
411 	case DASDAPIVER:
412 		return dasd_ioctl_api_version(argp);
413 	case BIODASDCMFENABLE:
414 		return enable_cmf(block->base->cdev);
415 	case BIODASDCMFDISABLE:
416 		return disable_cmf(block->base->cdev);
417 	case BIODASDREADALLCMB:
418 		return dasd_ioctl_readall_cmb(block, cmd, argp);
419 	default:
420 		/* if the discipline has an ioctl method try it. */
421 		if (block->base->discipline->ioctl) {
422 			int rval = block->base->discipline->ioctl(block, cmd, argp);
423 			if (rval != -ENOIOCTLCMD)
424 				return rval;
425 		}
426 
427 		return -EINVAL;
428 	}
429 }
430 
431 int dasd_ioctl(struct block_device *bdev, fmode_t mode,
432 	       unsigned int cmd, unsigned long arg)
433 {
434 	int rc;
435 
436 	lock_kernel();
437 	rc = dasd_do_ioctl(bdev, mode, cmd, arg);
438 	unlock_kernel();
439 	return rc;
440 }
441