xref: /openbmc/linux/drivers/s390/block/dasd_ioctl.c (revision 64c70b1c)
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 #include <linux/interrupt.h>
13 #include <linux/major.h>
14 #include <linux/fs.h>
15 #include <linux/blkpg.h>
16 
17 #include <asm/ccwdev.h>
18 #include <asm/cmb.h>
19 #include <asm/uaccess.h>
20 
21 /* This is ugly... */
22 #define PRINTK_HEADER "dasd_ioctl:"
23 
24 #include "dasd_int.h"
25 
26 
27 static int
28 dasd_ioctl_api_version(void __user *argp)
29 {
30 	int ver = DASD_API_VERSION;
31 	return put_user(ver, (int __user *)argp);
32 }
33 
34 /*
35  * Enable device.
36  * used by dasdfmt after BIODASDDISABLE to retrigger blocksize detection
37  */
38 static int
39 dasd_ioctl_enable(struct block_device *bdev)
40 {
41 	struct dasd_device *device = bdev->bd_disk->private_data;
42 
43 	if (!capable(CAP_SYS_ADMIN))
44 		return -EACCES;
45 
46 	dasd_enable_device(device);
47 	/* Formatting the dasd device can change the capacity. */
48 	mutex_lock(&bdev->bd_mutex);
49 	i_size_write(bdev->bd_inode, (loff_t)get_capacity(device->gdp) << 9);
50 	mutex_unlock(&bdev->bd_mutex);
51 	return 0;
52 }
53 
54 /*
55  * Disable device.
56  * Used by dasdfmt. Disable I/O operations but allow ioctls.
57  */
58 static int
59 dasd_ioctl_disable(struct block_device *bdev)
60 {
61 	struct dasd_device *device = bdev->bd_disk->private_data;
62 
63 	if (!capable(CAP_SYS_ADMIN))
64 		return -EACCES;
65 
66 	/*
67 	 * Man this is sick. We don't do a real disable but only downgrade
68 	 * the device to DASD_STATE_BASIC. The reason is that dasdfmt uses
69 	 * BIODASDDISABLE to disable accesses to the device via the block
70 	 * device layer but it still wants to do i/o on the device by
71 	 * using the BIODASDFMT ioctl. Therefore the correct state for the
72 	 * device is DASD_STATE_BASIC that allows to do basic i/o.
73 	 */
74 	dasd_set_target_state(device, DASD_STATE_BASIC);
75 	/*
76 	 * Set i_size to zero, since read, write, etc. check against this
77 	 * value.
78 	 */
79 	mutex_lock(&bdev->bd_mutex);
80 	i_size_write(bdev->bd_inode, 0);
81 	mutex_unlock(&bdev->bd_mutex);
82 	return 0;
83 }
84 
85 /*
86  * Quiesce device.
87  */
88 static int
89 dasd_ioctl_quiesce(struct dasd_device *device)
90 {
91 	unsigned long flags;
92 
93 	if (!capable (CAP_SYS_ADMIN))
94 		return -EACCES;
95 
96 	DEV_MESSAGE (KERN_DEBUG, device, "%s",
97 		     "Quiesce IO on device");
98 	spin_lock_irqsave(get_ccwdev_lock(device->cdev), flags);
99 	device->stopped |= DASD_STOPPED_QUIESCE;
100 	spin_unlock_irqrestore(get_ccwdev_lock(device->cdev), flags);
101 	return 0;
102 }
103 
104 
105 /*
106  * Quiesce device.
107  */
108 static int
109 dasd_ioctl_resume(struct dasd_device *device)
110 {
111 	unsigned long flags;
112 
113 	if (!capable (CAP_SYS_ADMIN))
114 		return -EACCES;
115 
116 	DEV_MESSAGE (KERN_DEBUG, device, "%s",
117 		     "resume IO on device");
118 
119 	spin_lock_irqsave(get_ccwdev_lock(device->cdev), flags);
120 	device->stopped &= ~DASD_STOPPED_QUIESCE;
121 	spin_unlock_irqrestore(get_ccwdev_lock(device->cdev), flags);
122 
123 	dasd_schedule_bh (device);
124 	return 0;
125 }
126 
127 /*
128  * performs formatting of _device_ according to _fdata_
129  * Note: The discipline's format_function is assumed to deliver formatting
130  * commands to format a single unit of the device. In terms of the ECKD
131  * devices this means CCWs are generated to format a single track.
132  */
133 static int
134 dasd_format(struct dasd_device * device, struct format_data_t * fdata)
135 {
136 	struct dasd_ccw_req *cqr;
137 	int rc;
138 
139 	if (device->discipline->format_device == NULL)
140 		return -EPERM;
141 
142 	if (device->state != DASD_STATE_BASIC) {
143 		DEV_MESSAGE(KERN_WARNING, device, "%s",
144 			    "dasd_format: device is not disabled! ");
145 		return -EBUSY;
146 	}
147 
148 	DBF_DEV_EVENT(DBF_NOTICE, device,
149 		      "formatting units %d to %d (%d B blocks) flags %d",
150 		      fdata->start_unit,
151 		      fdata->stop_unit, fdata->blksize, fdata->intensity);
152 
153 	/* Since dasdfmt keeps the device open after it was disabled,
154 	 * there still exists an inode for this device.
155 	 * We must update i_blkbits, otherwise we might get errors when
156 	 * enabling the device later.
157 	 */
158 	if (fdata->start_unit == 0) {
159 		struct block_device *bdev = bdget_disk(device->gdp, 0);
160 		bdev->bd_inode->i_blkbits = blksize_bits(fdata->blksize);
161 		bdput(bdev);
162 	}
163 
164 	while (fdata->start_unit <= fdata->stop_unit) {
165 		cqr = device->discipline->format_device(device, fdata);
166 		if (IS_ERR(cqr))
167 			return PTR_ERR(cqr);
168 		rc = dasd_sleep_on_interruptible(cqr);
169 		dasd_sfree_request(cqr, cqr->device);
170 		if (rc) {
171 			if (rc != -ERESTARTSYS)
172 				DEV_MESSAGE(KERN_ERR, device,
173 					    " Formatting of unit %d failed "
174 					    "with rc = %d",
175 					    fdata->start_unit, rc);
176 			return rc;
177 		}
178 		fdata->start_unit++;
179 	}
180 	return 0;
181 }
182 
183 /*
184  * Format device.
185  */
186 static int
187 dasd_ioctl_format(struct block_device *bdev, void __user *argp)
188 {
189 	struct dasd_device *device = bdev->bd_disk->private_data;
190 	struct format_data_t fdata;
191 
192 	if (!capable(CAP_SYS_ADMIN))
193 		return -EACCES;
194 	if (!argp)
195 		return -EINVAL;
196 
197 	if (device->features & DASD_FEATURE_READONLY)
198 		return -EROFS;
199 	if (copy_from_user(&fdata, argp, sizeof(struct format_data_t)))
200 		return -EFAULT;
201 	if (bdev != bdev->bd_contains) {
202 		DEV_MESSAGE(KERN_WARNING, device, "%s",
203 			    "Cannot low-level format a partition");
204 		return -EINVAL;
205 	}
206 	return dasd_format(device, &fdata);
207 }
208 
209 #ifdef CONFIG_DASD_PROFILE
210 /*
211  * Reset device profile information
212  */
213 static int
214 dasd_ioctl_reset_profile(struct dasd_device *device)
215 {
216 	memset(&device->profile, 0, sizeof (struct dasd_profile_info_t));
217 	return 0;
218 }
219 
220 /*
221  * Return device profile information
222  */
223 static int
224 dasd_ioctl_read_profile(struct dasd_device *device, void __user *argp)
225 {
226 	if (dasd_profile_level == DASD_PROFILE_OFF)
227 		return -EIO;
228 	if (copy_to_user(argp, &device->profile,
229 			 sizeof (struct dasd_profile_info_t)))
230 		return -EFAULT;
231 	return 0;
232 }
233 #else
234 static int
235 dasd_ioctl_reset_profile(struct dasd_device *device)
236 {
237 	return -ENOSYS;
238 }
239 
240 static int
241 dasd_ioctl_read_profile(struct dasd_device *device, void __user *argp)
242 {
243 	return -ENOSYS;
244 }
245 #endif
246 
247 /*
248  * Return dasd information. Used for BIODASDINFO and BIODASDINFO2.
249  */
250 static int
251 dasd_ioctl_information(struct dasd_device *device,
252 		unsigned int cmd, void __user *argp)
253 {
254 	struct dasd_information2_t *dasd_info;
255 	unsigned long flags;
256 	int rc;
257 	struct ccw_device *cdev;
258 	struct ccw_dev_id dev_id;
259 
260 	if (!device->discipline->fill_info)
261 		return -EINVAL;
262 
263 	dasd_info = kzalloc(sizeof(struct dasd_information2_t), GFP_KERNEL);
264 	if (dasd_info == NULL)
265 		return -ENOMEM;
266 
267 	rc = device->discipline->fill_info(device, dasd_info);
268 	if (rc) {
269 		kfree(dasd_info);
270 		return rc;
271 	}
272 
273 	cdev = device->cdev;
274 	ccw_device_get_id(cdev, &dev_id);
275 
276 	dasd_info->devno = dev_id.devno;
277 	dasd_info->schid = _ccw_device_get_subchannel_number(device->cdev);
278 	dasd_info->cu_type = cdev->id.cu_type;
279 	dasd_info->cu_model = cdev->id.cu_model;
280 	dasd_info->dev_type = cdev->id.dev_type;
281 	dasd_info->dev_model = cdev->id.dev_model;
282 	dasd_info->status = device->state;
283 	/*
284 	 * The open_count is increased for every opener, that includes
285 	 * the blkdev_get in dasd_scan_partitions.
286 	 * This must be hidden from user-space.
287 	 */
288 	dasd_info->open_count = atomic_read(&device->open_count);
289 	if (!device->bdev)
290 		dasd_info->open_count++;
291 
292 	/*
293 	 * check if device is really formatted
294 	 * LDL / CDL was returned by 'fill_info'
295 	 */
296 	if ((device->state < DASD_STATE_READY) ||
297 	    (dasd_check_blocksize(device->bp_block)))
298 		dasd_info->format = DASD_FORMAT_NONE;
299 
300 	dasd_info->features |=
301 		((device->features & DASD_FEATURE_READONLY) != 0);
302 
303 	if (device->discipline)
304 		memcpy(dasd_info->type, device->discipline->name, 4);
305 	else
306 		memcpy(dasd_info->type, "none", 4);
307 
308 	if (device->request_queue->request_fn) {
309 		struct list_head *l;
310 #ifdef DASD_EXTENDED_PROFILING
311 		{
312 			struct list_head *l;
313 			spin_lock_irqsave(&device->lock, flags);
314 			list_for_each(l, &device->request_queue->queue_head)
315 				dasd_info->req_queue_len++;
316 			spin_unlock_irqrestore(&device->lock, flags);
317 		}
318 #endif				/* DASD_EXTENDED_PROFILING */
319 		spin_lock_irqsave(get_ccwdev_lock(device->cdev), flags);
320 		list_for_each(l, &device->ccw_queue)
321 			dasd_info->chanq_len++;
322 		spin_unlock_irqrestore(get_ccwdev_lock(device->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_device *device =  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(device->cdev, DASD_FEATURE_READONLY, intval);
355 }
356 
357 static int
358 dasd_ioctl_readall_cmb(struct dasd_device *device, unsigned int cmd,
359 		unsigned long arg)
360 {
361 	struct cmbdata __user *argp = (void __user *) arg;
362 	size_t size = _IOC_SIZE(cmd);
363 	struct cmbdata data;
364 	int ret;
365 
366 	ret = cmf_readall(device->cdev, &data);
367 	if (!ret && copy_to_user(argp, &data, min(size, sizeof(*argp))))
368 		return -EFAULT;
369 	return ret;
370 }
371 
372 int
373 dasd_ioctl(struct inode *inode, struct file *file,
374 	   unsigned int cmd, unsigned long arg)
375 {
376 	struct block_device *bdev = inode->i_bdev;
377 	struct dasd_device *device = bdev->bd_disk->private_data;
378 	void __user *argp = (void __user *)arg;
379 
380 	if (!device)
381                 return -ENODEV;
382 
383 	if ((_IOC_DIR(cmd) != _IOC_NONE) && !arg) {
384 		PRINT_DEBUG("empty data ptr");
385 		return -EINVAL;
386 	}
387 
388 	switch (cmd) {
389 	case BIODASDDISABLE:
390 		return dasd_ioctl_disable(bdev);
391 	case BIODASDENABLE:
392 		return dasd_ioctl_enable(bdev);
393 	case BIODASDQUIESCE:
394 		return dasd_ioctl_quiesce(device);
395 	case BIODASDRESUME:
396 		return dasd_ioctl_resume(device);
397 	case BIODASDFMT:
398 		return dasd_ioctl_format(bdev, argp);
399 	case BIODASDINFO:
400 		return dasd_ioctl_information(device, cmd, argp);
401 	case BIODASDINFO2:
402 		return dasd_ioctl_information(device, cmd, argp);
403 	case BIODASDPRRD:
404 		return dasd_ioctl_read_profile(device, argp);
405 	case BIODASDPRRST:
406 		return dasd_ioctl_reset_profile(device);
407 	case BLKROSET:
408 		return dasd_ioctl_set_ro(bdev, argp);
409 	case DASDAPIVER:
410 		return dasd_ioctl_api_version(argp);
411 	case BIODASDCMFENABLE:
412 		return enable_cmf(device->cdev);
413 	case BIODASDCMFDISABLE:
414 		return disable_cmf(device->cdev);
415 	case BIODASDREADALLCMB:
416 		return dasd_ioctl_readall_cmb(device, cmd, arg);
417 	default:
418 		/* if the discipline has an ioctl method try it. */
419 		if (device->discipline->ioctl) {
420 			int rval = device->discipline->ioctl(device, cmd, argp);
421 			if (rval != -ENOIOCTLCMD)
422 				return rval;
423 		}
424 
425 		return -EINVAL;
426 	}
427 }
428 
429 long
430 dasd_compat_ioctl(struct file *filp, unsigned int cmd, unsigned long arg)
431 {
432 	int rval;
433 
434 	lock_kernel();
435 	rval = dasd_ioctl(filp->f_path.dentry->d_inode, filp, cmd, arg);
436 	unlock_kernel();
437 
438 	return (rval == -EINVAL) ? -ENOIOCTLCMD : rval;
439 }
440