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 __user *)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 }