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 block_device *bdev, fmode_t mode,
 370            unsigned int cmd, unsigned long arg)
 371 {
 372         struct dasd_block *block = bdev->bd_disk->private_data;
 373         void __user *argp = (void __user *)arg;
 374
 375         if (!block)
 376                 return -ENODEV;
 377
 378         if ((_IOC_DIR(cmd) != _IOC_NONE) && !arg) {
 379                 PRINT_DEBUG("empty data ptr");
 380                 return -EINVAL;
 381         }
 382
 383         switch (cmd) {
 384         case BIODASDDISABLE:
 385                 return dasd_ioctl_disable(bdev);
 386         case BIODASDENABLE:
 387                 return dasd_ioctl_enable(bdev);
 388         case BIODASDQUIESCE:
 389                 return dasd_ioctl_quiesce(block);
 390         case BIODASDRESUME:
 391                 return dasd_ioctl_resume(block);
 392         case BIODASDFMT:
 393                 return dasd_ioctl_format(bdev, argp);
 394         case BIODASDINFO:
 395                 return dasd_ioctl_information(block, cmd, argp);
 396         case BIODASDINFO2:
 397                 return dasd_ioctl_information(block, cmd, argp);
 398         case BIODASDPRRD:
 399                 return dasd_ioctl_read_profile(block, argp);
 400         case BIODASDPRRST:
 401                 return dasd_ioctl_reset_profile(block);
 402         case BLKROSET:
 403                 return dasd_ioctl_set_ro(bdev, argp);
 404         case DASDAPIVER:
 405                 return dasd_ioctl_api_version(argp);
 406         case BIODASDCMFENABLE:
 407                 return enable_cmf(block->base->cdev);
 408         case BIODASDCMFDISABLE:
 409                 return disable_cmf(block->base->cdev);
 410         case BIODASDREADALLCMB:
 411                 return dasd_ioctl_readall_cmb(block, cmd, arg);
 412         default:
 413                 /* if the discipline has an ioctl method try it. */
 414                 if (block->base->discipline->ioctl) {
 415                         int rval = block->base->discipline->ioctl(block, cmd, argp);
 416                         if (rval != -ENOIOCTLCMD)
 417                                 return rval;
 418                 }
 419
 420                 return -EINVAL;
 421         }
 422 }