Merge branch 'core/printk' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux...
[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_block *block = bdev->bd_disk->private_data;
42
43         if (!capable(CAP_SYS_ADMIN))
44                 return -EACCES;
45
46         dasd_enable_device(block->base);
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(block->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_block *block = 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(block->base, 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 dasd_ioctl_quiesce(struct dasd_block *block)
89 {
90         unsigned long flags;
91         struct dasd_device *base;
92
93         base = block->base;
94         if (!capable (CAP_SYS_ADMIN))
95                 return -EACCES;
96
97         DEV_MESSAGE(KERN_DEBUG, base, "%s", "Quiesce IO on device");
98         spin_lock_irqsave(get_ccwdev_lock(base->cdev), flags);
99         base->stopped |= DASD_STOPPED_QUIESCE;
100         spin_unlock_irqrestore(get_ccwdev_lock(base->cdev), flags);
101         return 0;
102 }
103
104
105 /*
106  * Quiesce device.
107  */
108 static int dasd_ioctl_resume(struct dasd_block *block)
109 {
110         unsigned long flags;
111         struct dasd_device *base;
112
113         base = block->base;
114         if (!capable (CAP_SYS_ADMIN))
115                 return -EACCES;
116
117         DEV_MESSAGE(KERN_DEBUG, base, "%s", "resume IO on device");
118         spin_lock_irqsave(get_ccwdev_lock(base->cdev), flags);
119         base->stopped &= ~DASD_STOPPED_QUIESCE;
120         spin_unlock_irqrestore(get_ccwdev_lock(base->cdev), flags);
121
122         dasd_schedule_block_bh(block);
123         return 0;
124 }
125
126 /*
127  * performs formatting of _device_ according to _fdata_
128  * Note: The discipline's format_function is assumed to deliver formatting
129  * commands to format a single unit of the device. In terms of the ECKD
130  * devices this means CCWs are generated to format a single track.
131  */
132 static int dasd_format(struct dasd_block *block, struct format_data_t *fdata)
133 {
134         struct dasd_ccw_req *cqr;
135         struct dasd_device *base;
136         int rc;
137
138         base = block->base;
139         if (base->discipline->format_device == NULL)
140                 return -EPERM;
141
142         if (base->state != DASD_STATE_BASIC) {
143                 DEV_MESSAGE(KERN_WARNING, base, "%s",
144                             "dasd_format: device is not disabled! ");
145                 return -EBUSY;
146         }
147
148         DBF_DEV_EVENT(DBF_NOTICE, base,
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(block->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 = base->discipline->format_device(base, fdata);
166                 if (IS_ERR(cqr))
167                         return PTR_ERR(cqr);
168                 rc = dasd_sleep_on_interruptible(cqr);
169                 dasd_sfree_request(cqr, cqr->memdev);
170                 if (rc) {
171                         if (rc != -ERESTARTSYS)
172                                 DEV_MESSAGE(KERN_ERR, base,
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_block *block = 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 (block->base->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, block->base, "%s",
203                             "Cannot low-level format a partition");
204                 return -EINVAL;
205         }
206         return dasd_format(block, &fdata);
207 }
208
209 #ifdef CONFIG_DASD_PROFILE
210 /*
211  * Reset device profile information
212  */
213 static int dasd_ioctl_reset_profile(struct dasd_block *block)
214 {
215         memset(&block->profile, 0, sizeof(struct dasd_profile_info_t));
216         return 0;
217 }
218
219 /*
220  * Return device profile information
221  */
222 static int dasd_ioctl_read_profile(struct dasd_block *block, void __user *argp)
223 {
224         if (dasd_profile_level == DASD_PROFILE_OFF)
225                 return -EIO;
226         if (copy_to_user(argp, &block->profile,
227                          sizeof(struct dasd_profile_info_t)))
228                 return -EFAULT;
229         return 0;
230 }
231 #else
232 static int dasd_ioctl_reset_profile(struct dasd_block *block)
233 {
234         return -ENOSYS;
235 }
236
237 static int dasd_ioctl_read_profile(struct dasd_block *block, void __user *argp)
238 {
239         return -ENOSYS;
240 }
241 #endif
242
243 /*
244  * Return dasd information. Used for BIODASDINFO and BIODASDINFO2.
245  */
246 static int dasd_ioctl_information(struct dasd_block *block,
247                                   unsigned int cmd, void __user *argp)
248 {
249         struct dasd_information2_t *dasd_info;
250         unsigned long flags;
251         int rc;
252         struct dasd_device *base;
253         struct ccw_device *cdev;
254         struct ccw_dev_id dev_id;
255
256         base = block->base;
257         if (!base->discipline->fill_info)
258                 return -EINVAL;
259
260         dasd_info = kzalloc(sizeof(struct dasd_information2_t), GFP_KERNEL);
261         if (dasd_info == NULL)
262                 return -ENOMEM;
263
264         rc = base->discipline->fill_info(base, dasd_info);
265         if (rc) {
266                 kfree(dasd_info);
267                 return rc;
268         }
269
270         cdev = base->cdev;
271         ccw_device_get_id(cdev, &dev_id);
272
273         dasd_info->devno = dev_id.devno;
274         dasd_info->schid = _ccw_device_get_subchannel_number(base->cdev);
275         dasd_info->cu_type = cdev->id.cu_type;
276         dasd_info->cu_model = cdev->id.cu_model;
277         dasd_info->dev_type = cdev->id.dev_type;
278         dasd_info->dev_model = cdev->id.dev_model;
279         dasd_info->status = base->state;
280         /*
281          * The open_count is increased for every opener, that includes
282          * the blkdev_get in dasd_scan_partitions.
283          * This must be hidden from user-space.
284          */
285         dasd_info->open_count = atomic_read(&block->open_count);
286         if (!block->bdev)
287                 dasd_info->open_count++;
288
289         /*
290          * check if device is really formatted
291          * LDL / CDL was returned by 'fill_info'
292          */
293         if ((base->state < DASD_STATE_READY) ||
294             (dasd_check_blocksize(block->bp_block)))
295                 dasd_info->format = DASD_FORMAT_NONE;
296
297         dasd_info->features |=
298                 ((base->features & DASD_FEATURE_READONLY) != 0);
299
300         if (base->discipline)
301                 memcpy(dasd_info->type, base->discipline->name, 4);
302         else
303                 memcpy(dasd_info->type, "none", 4);
304
305         if (block->request_queue->request_fn) {
306                 struct list_head *l;
307 #ifdef DASD_EXTENDED_PROFILING
308                 {
309                         struct list_head *l;
310                         spin_lock_irqsave(&block->lock, flags);
311                         list_for_each(l, &block->request_queue->queue_head)
312                                 dasd_info->req_queue_len++;
313                         spin_unlock_irqrestore(&block->lock, flags);
314                 }
315 #endif                          /* DASD_EXTENDED_PROFILING */
316                 spin_lock_irqsave(get_ccwdev_lock(base->cdev), flags);
317                 list_for_each(l, &base->ccw_queue)
318                         dasd_info->chanq_len++;
319                 spin_unlock_irqrestore(get_ccwdev_lock(base->cdev),
320                                        flags);
321         }
322
323         rc = 0;
324         if (copy_to_user(argp, dasd_info,
325                          ((cmd == (unsigned int) BIODASDINFO2) ?
326                           sizeof(struct dasd_information2_t) :
327                           sizeof(struct dasd_information_t))))
328                 rc = -EFAULT;
329         kfree(dasd_info);
330         return rc;
331 }
332
333 /*
334  * Set read only
335  */
336 static int
337 dasd_ioctl_set_ro(struct block_device *bdev, void __user *argp)
338 {
339         struct dasd_block *block =  bdev->bd_disk->private_data;
340         int intval;
341
342         if (!capable(CAP_SYS_ADMIN))
343                 return -EACCES;
344         if (bdev != bdev->bd_contains)
345                 // ro setting is not allowed for partitions
346                 return -EINVAL;
347         if (get_user(intval, (int __user *)argp))
348                 return -EFAULT;
349
350         set_disk_ro(bdev->bd_disk, intval);
351         return dasd_set_feature(block->base->cdev, DASD_FEATURE_READONLY, intval);
352 }
353
354 static int dasd_ioctl_readall_cmb(struct dasd_block *block, unsigned int cmd,
355                 unsigned long arg)
356 {
357         struct cmbdata __user *argp = (void __user *) arg;
358         size_t size = _IOC_SIZE(cmd);
359         struct cmbdata data;
360         int ret;
361
362         ret = cmf_readall(block->base->cdev, &data);
363         if (!ret && copy_to_user(argp, &data, min(size, sizeof(*argp))))
364                 return -EFAULT;
365         return ret;
366 }
367
368 int
369 dasd_ioctl(struct inode *inode, struct file *file,
370            unsigned int cmd, unsigned long arg)
371 {
372         struct block_device *bdev = inode->i_bdev;
373         struct dasd_block *block = bdev->bd_disk->private_data;
374         void __user *argp = (void __user *)arg;
375
376         if (!block)
377                 return -ENODEV;
378
379         if ((_IOC_DIR(cmd) != _IOC_NONE) && !arg) {
380                 PRINT_DEBUG("empty data ptr");
381                 return -EINVAL;
382         }
383
384         switch (cmd) {
385         case BIODASDDISABLE:
386                 return dasd_ioctl_disable(bdev);
387         case BIODASDENABLE:
388                 return dasd_ioctl_enable(bdev);
389         case BIODASDQUIESCE:
390                 return dasd_ioctl_quiesce(block);
391         case BIODASDRESUME:
392                 return dasd_ioctl_resume(block);
393         case BIODASDFMT:
394                 return dasd_ioctl_format(bdev, argp);
395         case BIODASDINFO:
396                 return dasd_ioctl_information(block, cmd, argp);
397         case BIODASDINFO2:
398                 return dasd_ioctl_information(block, cmd, argp);
399         case BIODASDPRRD:
400                 return dasd_ioctl_read_profile(block, argp);
401         case BIODASDPRRST:
402                 return dasd_ioctl_reset_profile(block);
403         case BLKROSET:
404                 return dasd_ioctl_set_ro(bdev, argp);
405         case DASDAPIVER:
406                 return dasd_ioctl_api_version(argp);
407         case BIODASDCMFENABLE:
408                 return enable_cmf(block->base->cdev);
409         case BIODASDCMFDISABLE:
410                 return disable_cmf(block->base->cdev);
411         case BIODASDREADALLCMB:
412                 return dasd_ioctl_readall_cmb(block, cmd, arg);
413         default:
414                 /* if the discipline has an ioctl method try it. */
415                 if (block->base->discipline->ioctl) {
416                         int rval = block->base->discipline->ioctl(block, cmd, argp);
417                         if (rval != -ENOIOCTLCMD)
418                                 return rval;
419                 }
420
421                 return -EINVAL;
422         }
423 }
424
425 long
426 dasd_compat_ioctl(struct file *filp, unsigned int cmd, unsigned long arg)
427 {
428         int rval;
429
430         lock_kernel();
431         rval = dasd_ioctl(filp->f_path.dentry->d_inode, filp, cmd, arg);
432         unlock_kernel();
433
434         return (rval == -EINVAL) ? -ENOIOCTLCMD : rval;
435 }