Merge master.kernel.org:/home/rmk/linux-2.6-arm
[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/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 }