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 }