Merge git://git.kernel.org/pub/scm/linux/kernel/git/bunk/trivial
[linux-2.6] / drivers / s390 / block / dasd_ioctl.c
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
259         if (!device->discipline->fill_info)
260                 return -EINVAL;
261
262         dasd_info = kzalloc(sizeof(struct dasd_information2_t), GFP_KERNEL);
263         if (dasd_info == NULL)
264                 return -ENOMEM;
265
266         rc = device->discipline->fill_info(device, dasd_info);
267         if (rc) {
268                 kfree(dasd_info);
269                 return rc;
270         }
271
272         cdev = device->cdev;
273
274         dasd_info->devno = _ccw_device_get_device_number(device->cdev);
275         dasd_info->schid = _ccw_device_get_subchannel_number(device->cdev);
276         dasd_info->cu_type = cdev->id.cu_type;
277         dasd_info->cu_model = cdev->id.cu_model;
278         dasd_info->dev_type = cdev->id.dev_type;
279         dasd_info->dev_model = cdev->id.dev_model;
280         dasd_info->status = device->state;
281         /*
282          * The open_count is increased for every opener, that includes
283          * the blkdev_get in dasd_scan_partitions.
284          * This must be hidden from user-space.
285          */
286         dasd_info->open_count = atomic_read(&device->open_count);
287         if (!device->bdev)
288                 dasd_info->open_count++;
289
290         /*
291          * check if device is really formatted
292          * LDL / CDL was returned by 'fill_info'
293          */
294         if ((device->state < DASD_STATE_READY) ||
295             (dasd_check_blocksize(device->bp_block)))
296                 dasd_info->format = DASD_FORMAT_NONE;
297
298         dasd_info->features |=
299                 ((device->features & DASD_FEATURE_READONLY) != 0);
300
301         if (device->discipline)
302                 memcpy(dasd_info->type, device->discipline->name, 4);
303         else
304                 memcpy(dasd_info->type, "none", 4);
305
306         if (device->request_queue->request_fn) {
307                 struct list_head *l;
308 #ifdef DASD_EXTENDED_PROFILING
309                 {
310                         struct list_head *l;
311                         spin_lock_irqsave(&device->lock, flags);
312                         list_for_each(l, &device->request_queue->queue_head)
313                                 dasd_info->req_queue_len++;
314                         spin_unlock_irqrestore(&device->lock, flags);
315                 }
316 #endif                          /* DASD_EXTENDED_PROFILING */
317                 spin_lock_irqsave(get_ccwdev_lock(device->cdev), flags);
318                 list_for_each(l, &device->ccw_queue)
319                         dasd_info->chanq_len++;
320                 spin_unlock_irqrestore(get_ccwdev_lock(device->cdev),
321                                        flags);
322         }
323
324         rc = 0;
325         if (copy_to_user(argp, dasd_info,
326                          ((cmd == (unsigned int) BIODASDINFO2) ?
327                           sizeof (struct dasd_information2_t) :
328                           sizeof (struct dasd_information_t))))
329                 rc = -EFAULT;
330         kfree(dasd_info);
331         return rc;
332 }
333
334 /*
335  * Set read only
336  */
337 static int
338 dasd_ioctl_set_ro(struct block_device *bdev, void __user *argp)
339 {
340         struct dasd_device *device =  bdev->bd_disk->private_data;
341         int intval;
342
343         if (!capable(CAP_SYS_ADMIN))
344                 return -EACCES;
345         if (bdev != bdev->bd_contains)
346                 // ro setting is not allowed for partitions
347                 return -EINVAL;
348         if (get_user(intval, (int *)argp))
349                 return -EFAULT;
350
351         set_disk_ro(bdev->bd_disk, intval);
352         return dasd_set_feature(device->cdev, DASD_FEATURE_READONLY, intval);
353 }
354
355 static int
356 dasd_ioctl_readall_cmb(struct dasd_device *device, unsigned int cmd,
357                 unsigned long arg)
358 {
359         struct cmbdata __user *argp = (void __user *) arg;
360         size_t size = _IOC_SIZE(cmd);
361         struct cmbdata data;
362         int ret;
363
364         ret = cmf_readall(device->cdev, &data);
365         if (!ret && copy_to_user(argp, &data, min(size, sizeof(*argp))))
366                 return -EFAULT;
367         return ret;
368 }
369
370 int
371 dasd_ioctl(struct inode *inode, struct file *file,
372            unsigned int cmd, unsigned long arg)
373 {
374         struct block_device *bdev = inode->i_bdev;
375         struct dasd_device *device = bdev->bd_disk->private_data;
376         void __user *argp = (void __user *)arg;
377
378         if (!device)
379                 return -ENODEV;
380
381         if ((_IOC_DIR(cmd) != _IOC_NONE) && !arg) {
382                 PRINT_DEBUG("empty data ptr");
383                 return -EINVAL;
384         }
385
386         switch (cmd) {
387         case BIODASDDISABLE:
388                 return dasd_ioctl_disable(bdev);
389         case BIODASDENABLE:
390                 return dasd_ioctl_enable(bdev);
391         case BIODASDQUIESCE:
392                 return dasd_ioctl_quiesce(device);
393         case BIODASDRESUME:
394                 return dasd_ioctl_resume(device);
395         case BIODASDFMT:
396                 return dasd_ioctl_format(bdev, argp);
397         case BIODASDINFO:
398                 return dasd_ioctl_information(device, cmd, argp);
399         case BIODASDINFO2:
400                 return dasd_ioctl_information(device, cmd, argp);
401         case BIODASDPRRD:
402                 return dasd_ioctl_read_profile(device, argp);
403         case BIODASDPRRST:
404                 return dasd_ioctl_reset_profile(device);
405         case BLKROSET:
406                 return dasd_ioctl_set_ro(bdev, argp);
407         case DASDAPIVER:
408                 return dasd_ioctl_api_version(argp);
409         case BIODASDCMFENABLE:
410                 return enable_cmf(device->cdev);
411         case BIODASDCMFDISABLE:
412                 return disable_cmf(device->cdev);
413         case BIODASDREADALLCMB:
414                 return dasd_ioctl_readall_cmb(device, cmd, arg);
415         default:
416                 /* if the discipline has an ioctl method try it. */
417                 if (device->discipline->ioctl) {
418                         int rval = device->discipline->ioctl(device, cmd, argp);
419                         if (rval != -ENOIOCTLCMD)
420                                 return rval;
421                 }
422
423                 return -EINVAL;
424         }
425 }
426
427 long
428 dasd_compat_ioctl(struct file *filp, unsigned int cmd, unsigned long arg)
429 {
430         int rval;
431
432         lock_kernel();
433         rval = dasd_ioctl(filp->f_dentry->d_inode, filp, cmd, arg);
434         unlock_kernel();
435
436         return (rval == -EINVAL) ? -ENOIOCTLCMD : rval;
437 }