xref: /linux/drivers/s390/block/dasd_ioctl.c (revision 86579dd06deecfa6ac88d5e84e4d63c397cd6f6d)
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/config.h>
13 #include <linux/interrupt.h>
14 #include <linux/major.h>
15 #include <linux/fs.h>
16 #include <linux/blkpg.h>
17 
18 #include <asm/ccwdev.h>
19 #include <asm/cmb.h>
20 #include <asm/uaccess.h>
21 
22 /* This is ugly... */
23 #define PRINTK_HEADER "dasd_ioctl:"
24 
25 #include "dasd_int.h"
26 
27 
28 static int
29 dasd_ioctl_api_version(void __user *argp)
30 {
31 	int ver = DASD_API_VERSION;
32 	return put_user(ver, (int __user *)argp);
33 }
34 
35 /*
36  * Enable device.
37  * used by dasdfmt after BIODASDDISABLE to retrigger blocksize detection
38  */
39 static int
40 dasd_ioctl_enable(struct block_device *bdev)
41 {
42 	struct dasd_device *device = bdev->bd_disk->private_data;
43 
44 	if (!capable(CAP_SYS_ADMIN))
45 		return -EACCES;
46 
47 	dasd_enable_device(device);
48 	/* Formatting the dasd device can change the capacity. */
49 	mutex_lock(&bdev->bd_mutex);
50 	i_size_write(bdev->bd_inode, (loff_t)get_capacity(device->gdp) << 9);
51 	mutex_unlock(&bdev->bd_mutex);
52 	return 0;
53 }
54 
55 /*
56  * Disable device.
57  * Used by dasdfmt. Disable I/O operations but allow ioctls.
58  */
59 static int
60 dasd_ioctl_disable(struct block_device *bdev)
61 {
62 	struct dasd_device *device = bdev->bd_disk->private_data;
63 
64 	if (!capable(CAP_SYS_ADMIN))
65 		return -EACCES;
66 
67 	/*
68 	 * Man this is sick. We don't do a real disable but only downgrade
69 	 * the device to DASD_STATE_BASIC. The reason is that dasdfmt uses
70 	 * BIODASDDISABLE to disable accesses to the device via the block
71 	 * device layer but it still wants to do i/o on the device by
72 	 * using the BIODASDFMT ioctl. Therefore the correct state for the
73 	 * device is DASD_STATE_BASIC that allows to do basic i/o.
74 	 */
75 	dasd_set_target_state(device, DASD_STATE_BASIC);
76 	/*
77 	 * Set i_size to zero, since read, write, etc. check against this
78 	 * value.
79 	 */
80 	mutex_lock(&bdev->bd_mutex);
81 	i_size_write(bdev->bd_inode, 0);
82 	mutex_unlock(&bdev->bd_mutex);
83 	return 0;
84 }
85 
86 /*
87  * Quiesce device.
88  */
89 static int
90 dasd_ioctl_quiesce(struct dasd_device *device)
91 {
92 	unsigned long flags;
93 
94 	if (!capable (CAP_SYS_ADMIN))
95 		return -EACCES;
96 
97 	DEV_MESSAGE (KERN_DEBUG, device, "%s",
98 		     "Quiesce IO on device");
99 	spin_lock_irqsave(get_ccwdev_lock(device->cdev), flags);
100 	device->stopped |= DASD_STOPPED_QUIESCE;
101 	spin_unlock_irqrestore(get_ccwdev_lock(device->cdev), flags);
102 	return 0;
103 }
104 
105 
106 /*
107  * Quiesce device.
108  */
109 static int
110 dasd_ioctl_resume(struct dasd_device *device)
111 {
112 	unsigned long flags;
113 
114 	if (!capable (CAP_SYS_ADMIN))
115 		return -EACCES;
116 
117 	DEV_MESSAGE (KERN_DEBUG, device, "%s",
118 		     "resume IO on device");
119 
120 	spin_lock_irqsave(get_ccwdev_lock(device->cdev), flags);
121 	device->stopped &= ~DASD_STOPPED_QUIESCE;
122 	spin_unlock_irqrestore(get_ccwdev_lock(device->cdev), flags);
123 
124 	dasd_schedule_bh (device);
125 	return 0;
126 }
127 
128 /*
129  * performs formatting of _device_ according to _fdata_
130  * Note: The discipline's format_function is assumed to deliver formatting
131  * commands to format a single unit of the device. In terms of the ECKD
132  * devices this means CCWs are generated to format a single track.
133  */
134 static int
135 dasd_format(struct dasd_device * device, struct format_data_t * fdata)
136 {
137 	struct dasd_ccw_req *cqr;
138 	int rc;
139 
140 	if (device->discipline->format_device == NULL)
141 		return -EPERM;
142 
143 	if (device->state != DASD_STATE_BASIC) {
144 		DEV_MESSAGE(KERN_WARNING, device, "%s",
145 			    "dasd_format: device is not disabled! ");
146 		return -EBUSY;
147 	}
148 
149 	DBF_DEV_EVENT(DBF_NOTICE, device,
150 		      "formatting units %d to %d (%d B blocks) flags %d",
151 		      fdata->start_unit,
152 		      fdata->stop_unit, fdata->blksize, fdata->intensity);
153 
154 	/* Since dasdfmt keeps the device open after it was disabled,
155 	 * there still exists an inode for this device.
156 	 * We must update i_blkbits, otherwise we might get errors when
157 	 * enabling the device later.
158 	 */
159 	if (fdata->start_unit == 0) {
160 		struct block_device *bdev = bdget_disk(device->gdp, 0);
161 		bdev->bd_inode->i_blkbits = blksize_bits(fdata->blksize);
162 		bdput(bdev);
163 	}
164 
165 	while (fdata->start_unit <= fdata->stop_unit) {
166 		cqr = device->discipline->format_device(device, fdata);
167 		if (IS_ERR(cqr))
168 			return PTR_ERR(cqr);
169 		rc = dasd_sleep_on_interruptible(cqr);
170 		dasd_sfree_request(cqr, cqr->device);
171 		if (rc) {
172 			if (rc != -ERESTARTSYS)
173 				DEV_MESSAGE(KERN_ERR, device,
174 					    " Formatting of unit %d failed "
175 					    "with rc = %d",
176 					    fdata->start_unit, rc);
177 			return rc;
178 		}
179 		fdata->start_unit++;
180 	}
181 	return 0;
182 }
183 
184 /*
185  * Format device.
186  */
187 static int
188 dasd_ioctl_format(struct block_device *bdev, void __user *argp)
189 {
190 	struct dasd_device *device = bdev->bd_disk->private_data;
191 	struct format_data_t fdata;
192 
193 	if (!capable(CAP_SYS_ADMIN))
194 		return -EACCES;
195 	if (!argp)
196 		return -EINVAL;
197 
198 	if (device->features & DASD_FEATURE_READONLY)
199 		return -EROFS;
200 	if (copy_from_user(&fdata, argp, sizeof(struct format_data_t)))
201 		return -EFAULT;
202 	if (bdev != bdev->bd_contains) {
203 		DEV_MESSAGE(KERN_WARNING, device, "%s",
204 			    "Cannot low-level format a partition");
205 		return -EINVAL;
206 	}
207 	return dasd_format(device, &fdata);
208 }
209 
210 #ifdef CONFIG_DASD_PROFILE
211 /*
212  * Reset device profile information
213  */
214 static int
215 dasd_ioctl_reset_profile(struct dasd_device *device)
216 {
217 	memset(&device->profile, 0, sizeof (struct dasd_profile_info_t));
218 	return 0;
219 }
220 
221 /*
222  * Return device profile information
223  */
224 static int
225 dasd_ioctl_read_profile(struct dasd_device *device, void __user *argp)
226 {
227 	if (dasd_profile_level == DASD_PROFILE_OFF)
228 		return -EIO;
229 	if (copy_to_user(argp, &device->profile,
230 			 sizeof (struct dasd_profile_info_t)))
231 		return -EFAULT;
232 	return 0;
233 }
234 #else
235 static int
236 dasd_ioctl_reset_profile(struct dasd_device *device)
237 {
238 	return -ENOSYS;
239 }
240 
241 static int
242 dasd_ioctl_read_profile(struct dasd_device *device, void __user *argp)
243 {
244 	return -ENOSYS;
245 }
246 #endif
247 
248 /*
249  * Return dasd information. Used for BIODASDINFO and BIODASDINFO2.
250  */
251 static int
252 dasd_ioctl_information(struct dasd_device *device,
253 		unsigned int cmd, void __user *argp)
254 {
255 	struct dasd_information2_t *dasd_info;
256 	unsigned long flags;
257 	int rc;
258 	struct ccw_device *cdev;
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 
275 	dasd_info->devno = _ccw_device_get_device_number(device->cdev);
276 	dasd_info->schid = _ccw_device_get_subchannel_number(device->cdev);
277 	dasd_info->cu_type = cdev->id.cu_type;
278 	dasd_info->cu_model = cdev->id.cu_model;
279 	dasd_info->dev_type = cdev->id.dev_type;
280 	dasd_info->dev_model = cdev->id.dev_model;
281 	dasd_info->status = device->state;
282 	/*
283 	 * The open_count is increased for every opener, that includes
284 	 * the blkdev_get in dasd_scan_partitions.
285 	 * This must be hidden from user-space.
286 	 */
287 	dasd_info->open_count = atomic_read(&device->open_count);
288 	if (!device->bdev)
289 		dasd_info->open_count++;
290 
291 	/*
292 	 * check if device is really formatted
293 	 * LDL / CDL was returned by 'fill_info'
294 	 */
295 	if ((device->state < DASD_STATE_READY) ||
296 	    (dasd_check_blocksize(device->bp_block)))
297 		dasd_info->format = DASD_FORMAT_NONE;
298 
299 	dasd_info->features |=
300 		((device->features & DASD_FEATURE_READONLY) != 0);
301 
302 	if (device->discipline)
303 		memcpy(dasd_info->type, device->discipline->name, 4);
304 	else
305 		memcpy(dasd_info->type, "none", 4);
306 
307 	if (device->request_queue->request_fn) {
308 		struct list_head *l;
309 #ifdef DASD_EXTENDED_PROFILING
310 		{
311 			struct list_head *l;
312 			spin_lock_irqsave(&device->lock, flags);
313 			list_for_each(l, &device->request_queue->queue_head)
314 				dasd_info->req_queue_len++;
315 			spin_unlock_irqrestore(&device->lock, flags);
316 		}
317 #endif				/* DASD_EXTENDED_PROFILING */
318 		spin_lock_irqsave(get_ccwdev_lock(device->cdev), flags);
319 		list_for_each(l, &device->ccw_queue)
320 			dasd_info->chanq_len++;
321 		spin_unlock_irqrestore(get_ccwdev_lock(device->cdev),
322 				       flags);
323 	}
324 
325 	rc = 0;
326 	if (copy_to_user(argp, dasd_info,
327 			 ((cmd == (unsigned int) BIODASDINFO2) ?
328 			  sizeof (struct dasd_information2_t) :
329 			  sizeof (struct dasd_information_t))))
330 		rc = -EFAULT;
331 	kfree(dasd_info);
332 	return rc;
333 }
334 
335 /*
336  * Set read only
337  */
338 static int
339 dasd_ioctl_set_ro(struct block_device *bdev, void __user *argp)
340 {
341 	struct dasd_device *device =  bdev->bd_disk->private_data;
342 	int intval;
343 
344 	if (!capable(CAP_SYS_ADMIN))
345 		return -EACCES;
346 	if (bdev != bdev->bd_contains)
347 		// ro setting is not allowed for partitions
348 		return -EINVAL;
349 	if (get_user(intval, (int *)argp))
350 		return -EFAULT;
351 
352 	set_disk_ro(bdev->bd_disk, intval);
353 	return dasd_set_feature(device->cdev, DASD_FEATURE_READONLY, intval);
354 }
355 
356 static int
357 dasd_ioctl_readall_cmb(struct dasd_device *device, unsigned int cmd,
358 		unsigned long arg)
359 {
360 	struct cmbdata __user *argp = (void __user *) arg;
361 	size_t size = _IOC_SIZE(cmd);
362 	struct cmbdata data;
363 	int ret;
364 
365 	ret = cmf_readall(device->cdev, &data);
366 	if (!ret && copy_to_user(argp, &data, min(size, sizeof(*argp))))
367 		return -EFAULT;
368 	return ret;
369 }
370 
371 int
372 dasd_ioctl(struct inode *inode, struct file *file,
373 	   unsigned int cmd, unsigned long arg)
374 {
375 	struct block_device *bdev = inode->i_bdev;
376 	struct dasd_device *device = bdev->bd_disk->private_data;
377 	void __user *argp = (void __user *)arg;
378 
379 	if (!device)
380                 return -ENODEV;
381 
382 	if ((_IOC_DIR(cmd) != _IOC_NONE) && !arg) {
383 		PRINT_DEBUG("empty data ptr");
384 		return -EINVAL;
385 	}
386 
387 	switch (cmd) {
388 	case BIODASDDISABLE:
389 		return dasd_ioctl_disable(bdev);
390 	case BIODASDENABLE:
391 		return dasd_ioctl_enable(bdev);
392 	case BIODASDQUIESCE:
393 		return dasd_ioctl_quiesce(device);
394 	case BIODASDRESUME:
395 		return dasd_ioctl_resume(device);
396 	case BIODASDFMT:
397 		return dasd_ioctl_format(bdev, argp);
398 	case BIODASDINFO:
399 		return dasd_ioctl_information(device, cmd, argp);
400 	case BIODASDINFO2:
401 		return dasd_ioctl_information(device, cmd, argp);
402 	case BIODASDPRRD:
403 		return dasd_ioctl_read_profile(device, argp);
404 	case BIODASDPRRST:
405 		return dasd_ioctl_reset_profile(device);
406 	case BLKROSET:
407 		return dasd_ioctl_set_ro(bdev, argp);
408 	case DASDAPIVER:
409 		return dasd_ioctl_api_version(argp);
410 	case BIODASDCMFENABLE:
411 		return enable_cmf(device->cdev);
412 	case BIODASDCMFDISABLE:
413 		return disable_cmf(device->cdev);
414 	case BIODASDREADALLCMB:
415 		return dasd_ioctl_readall_cmb(device, cmd, arg);
416 	default:
417 		/* if the discipline has an ioctl method try it. */
418 		if (device->discipline->ioctl) {
419 			int rval = device->discipline->ioctl(device, cmd, argp);
420 			if (rval != -ENOIOCTLCMD)
421 				return rval;
422 		}
423 
424 		return -EINVAL;
425 	}
426 }
427 
428 long
429 dasd_compat_ioctl(struct file *filp, unsigned int cmd, unsigned long arg)
430 {
431 	int rval;
432 
433 	lock_kernel();
434 	rval = dasd_ioctl(filp->f_dentry->d_inode, filp, cmd, arg);
435 	unlock_kernel();
436 
437 	return (rval == -EINVAL) ? -ENOIOCTLCMD : rval;
438 }
439