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
  13 #define KMSG_COMPONENT "dasd"
  14
  15 #include <linux/interrupt.h>
  16 #include <linux/compat.h>
  17 #include <linux/major.h>
  18 #include <linux/fs.h>
  19 #include <linux/blkpg.h>
  20 #include <linux/slab.h>
  21 #include <asm/compat.h>
  22 #include <asm/ccwdev.h>
  23 #include <asm/cmb.h>
  24 #include <asm/uaccess.h>
  25
  26 /* This is ugly... */
  27 #define PRINTK_HEADER "dasd_ioctl:"
  28
  29 #include "dasd_int.h"
  30
  31
  32 static int
  33 dasd_ioctl_api_version(void __user *argp)
  34 {
  35         int ver = DASD_API_VERSION;
  36         return put_user(ver, (int __user *)argp);
  37 }
  38
  39 /*
  40  * Enable device.
  41  * used by dasdfmt after BIODASDDISABLE to retrigger blocksize detection
  42  */
  43 static int
  44 dasd_ioctl_enable(struct block_device *bdev)
  45 {
  46         struct dasd_device *base;
  47
  48         if (!capable(CAP_SYS_ADMIN))
  49                 return -EACCES;
  50
  51         base = dasd_device_from_gendisk(bdev->bd_disk);
  52         if (!base)
  53                 return -ENODEV;
  54
  55         dasd_enable_device(base);
  56         /* Formatting the dasd device can change the capacity. */
  57         mutex_lock(&bdev->bd_mutex);
  58         i_size_write(bdev->bd_inode,
  59                      (loff_t)get_capacity(base->block->gdp) << 9);
  60         mutex_unlock(&bdev->bd_mutex);
  61         dasd_put_device(base);
  62         return 0;
  63 }
  64
  65 /*
  66  * Disable device.
  67  * Used by dasdfmt. Disable I/O operations but allow ioctls.
  68  */
  69 static int
  70 dasd_ioctl_disable(struct block_device *bdev)
  71 {
  72         struct dasd_device *base;
  73
  74         if (!capable(CAP_SYS_ADMIN))
  75                 return -EACCES;
  76
  77         base = dasd_device_from_gendisk(bdev->bd_disk);
  78         if (!base)
  79                 return -ENODEV;
  80         /*
  81          * Man this is sick. We don't do a real disable but only downgrade
  82          * the device to DASD_STATE_BASIC. The reason is that dasdfmt uses
  83          * BIODASDDISABLE to disable accesses to the device via the block
  84          * device layer but it still wants to do i/o on the device by
  85          * using the BIODASDFMT ioctl. Therefore the correct state for the
  86          * device is DASD_STATE_BASIC that allows to do basic i/o.
  87          */
  88         dasd_set_target_state(base, DASD_STATE_BASIC);
  89         /*
  90          * Set i_size to zero, since read, write, etc. check against this
  91          * value.
  92          */
  93         mutex_lock(&bdev->bd_mutex);
  94         i_size_write(bdev->bd_inode, 0);
  95         mutex_unlock(&bdev->bd_mutex);
  96         dasd_put_device(base);
  97         return 0;
  98 }
  99
 100 /*
 101  * Quiesce device.
 102  */
 103 static int dasd_ioctl_quiesce(struct dasd_block *block)
 104 {
 105         unsigned long flags;
 106         struct dasd_device *base;
 107
 108         base = block->base;
 109         if (!capable (CAP_SYS_ADMIN))
 110                 return -EACCES;
 111
 112         pr_info("%s: The DASD has been put in the quiesce "
 113                 "state\n", dev_name(&base->cdev->dev));
 114         spin_lock_irqsave(get_ccwdev_lock(base->cdev), flags);
 115         dasd_device_set_stop_bits(base, DASD_STOPPED_QUIESCE);
 116         spin_unlock_irqrestore(get_ccwdev_lock(base->cdev), flags);
 117         return 0;
 118 }
 119
 120
 121 /*
 122  * Resume device.
 123  */
 124 static int dasd_ioctl_resume(struct dasd_block *block)
 125 {
 126         unsigned long flags;
 127         struct dasd_device *base;
 128
 129         base = block->base;
 130         if (!capable (CAP_SYS_ADMIN))
 131                 return -EACCES;
 132
 133         pr_info("%s: I/O operations have been resumed "
 134                 "on the DASD\n", dev_name(&base->cdev->dev));
 135         spin_lock_irqsave(get_ccwdev_lock(base->cdev), flags);
 136         dasd_device_remove_stop_bits(base, DASD_STOPPED_QUIESCE);
 137         spin_unlock_irqrestore(get_ccwdev_lock(base->cdev), flags);
 138
 139         dasd_schedule_block_bh(block);
 140         return 0;
 141 }
 142
 143 /*
 144  * performs formatting of _device_ according to _fdata_
 145  * Note: The discipline's format_function is assumed to deliver formatting
 146  * commands to format a single unit of the device. In terms of the ECKD
 147  * devices this means CCWs are generated to format a single track.
 148  */
 149 static int dasd_format(struct dasd_block *block, struct format_data_t *fdata)
 150 {
 151         struct dasd_ccw_req *cqr;
 152         struct dasd_device *base;
 153         int rc;
 154
 155         base = block->base;
 156         if (base->discipline->format_device == NULL)
 157                 return -EPERM;
 158
 159         if (base->state != DASD_STATE_BASIC) {
 160                 pr_warning("%s: The DASD cannot be formatted while it is "
 161                            "enabled\n",  dev_name(&base->cdev->dev));
 162                 return -EBUSY;
 163         }
 164
 165         DBF_DEV_EVENT(DBF_NOTICE, base,
 166                       "formatting units %u to %u (%u B blocks) flags %u",
 167                       fdata->start_unit,
 168                       fdata->stop_unit, fdata->blksize, fdata->intensity);
 169
 170         /* Since dasdfmt keeps the device open after it was disabled,
 171          * there still exists an inode for this device.
 172          * We must update i_blkbits, otherwise we might get errors when
 173          * enabling the device later.
 174          */
 175         if (fdata->start_unit == 0) {
 176                 struct block_device *bdev = bdget_disk(block->gdp, 0);
 177                 bdev->bd_inode->i_blkbits = blksize_bits(fdata->blksize);
 178                 bdput(bdev);
 179         }
 180
 181         while (fdata->start_unit <= fdata->stop_unit) {
 182                 cqr = base->discipline->format_device(base, fdata);
 183                 if (IS_ERR(cqr))
 184                         return PTR_ERR(cqr);
 185                 rc = dasd_sleep_on_interruptible(cqr);
 186                 dasd_sfree_request(cqr, cqr->memdev);
 187                 if (rc) {
 188                         if (rc != -ERESTARTSYS)
 189                                 pr_err("%s: Formatting unit %d failed with "
 190                                        "rc=%d\n", dev_name(&base->cdev->dev),
 191                                        fdata->start_unit, rc);
 192                         return rc;
 193                 }
 194                 fdata->start_unit++;
 195         }
 196         return 0;
 197 }
 198
 199 /*
 200  * Format device.
 201  */
 202 static int
 203 dasd_ioctl_format(struct block_device *bdev, void __user *argp)
 204 {
 205         struct dasd_device *base;
 206         struct format_data_t fdata;
 207         int rc;
 208
 209         if (!capable(CAP_SYS_ADMIN))
 210                 return -EACCES;
 211         if (!argp)
 212                 return -EINVAL;
 213         base = dasd_device_from_gendisk(bdev->bd_disk);
 214         if (!base)
 215                 return -ENODEV;
 216         if (base->features & DASD_FEATURE_READONLY ||
 217             test_bit(DASD_FLAG_DEVICE_RO, &base->flags)) {
 218                 dasd_put_device(base);
 219                 return -EROFS;
 220         }
 221         if (copy_from_user(&fdata, argp, sizeof(struct format_data_t))) {
 222                 dasd_put_device(base);
 223                 return -EFAULT;
 224         }
 225         if (bdev != bdev->bd_contains) {
 226                 pr_warning("%s: The specified DASD is a partition and cannot "
 227                            "be formatted\n",
 228                            dev_name(&base->cdev->dev));
 229                 dasd_put_device(base);
 230                 return -EINVAL;
 231         }
 232         rc = dasd_format(base->block, &fdata);
 233         dasd_put_device(base);
 234         return rc;
 235 }
 236
 237 #ifdef CONFIG_DASD_PROFILE
 238 /*
 239  * Reset device profile information
 240  */
 241 static int dasd_ioctl_reset_profile(struct dasd_block *block)
 242 {
 243         memset(&block->profile, 0, sizeof(struct dasd_profile_info_t));
 244         return 0;
 245 }
 246
 247 /*
 248  * Return device profile information
 249  */
 250 static int dasd_ioctl_read_profile(struct dasd_block *block, void __user *argp)
 251 {
 252         if (dasd_profile_level == DASD_PROFILE_OFF)
 253                 return -EIO;
 254         if (copy_to_user(argp, &block->profile,
 255                          sizeof(struct dasd_profile_info_t)))
 256                 return -EFAULT;
 257         return 0;
 258 }
 259 #else
 260 static int dasd_ioctl_reset_profile(struct dasd_block *block)
 261 {
 262         return -ENOSYS;
 263 }
 264
 265 static int dasd_ioctl_read_profile(struct dasd_block *block, void __user *argp)
 266 {
 267         return -ENOSYS;
 268 }
 269 #endif
 270
 271 /*
 272  * Return dasd information. Used for BIODASDINFO and BIODASDINFO2.
 273  */
 274 static int dasd_ioctl_information(struct dasd_block *block,
 275                                   unsigned int cmd, void __user *argp)
 276 {
 277         struct dasd_information2_t *dasd_info;
 278         unsigned long flags;
 279         int rc;
 280         struct dasd_device *base;
 281         struct ccw_device *cdev;
 282         struct ccw_dev_id dev_id;
 283
 284         base = block->base;
 285         if (!base->discipline || !base->discipline->fill_info)
 286                 return -EINVAL;
 287
 288         dasd_info = kzalloc(sizeof(struct dasd_information2_t), GFP_KERNEL);
 289         if (dasd_info == NULL)
 290                 return -ENOMEM;
 291
 292         rc = base->discipline->fill_info(base, dasd_info);
 293         if (rc) {
 294                 kfree(dasd_info);
 295                 return rc;
 296         }
 297
 298         cdev = base->cdev;
 299         ccw_device_get_id(cdev, &dev_id);
 300
 301         dasd_info->devno = dev_id.devno;
 302         dasd_info->schid = _ccw_device_get_subchannel_number(base->cdev);
 303         dasd_info->cu_type = cdev->id.cu_type;
 304         dasd_info->cu_model = cdev->id.cu_model;
 305         dasd_info->dev_type = cdev->id.dev_type;
 306         dasd_info->dev_model = cdev->id.dev_model;
 307         dasd_info->status = base->state;
 308         /*
 309          * The open_count is increased for every opener, that includes
 310          * the blkdev_get in dasd_scan_partitions.
 311          * This must be hidden from user-space.
 312          */
 313         dasd_info->open_count = atomic_read(&block->open_count);
 314         if (!block->bdev)
 315                 dasd_info->open_count++;
 316
 317         /*
 318          * check if device is really formatted
 319          * LDL / CDL was returned by 'fill_info'
 320          */
 321         if ((base->state < DASD_STATE_READY) ||
 322             (dasd_check_blocksize(block->bp_block)))
 323                 dasd_info->format = DASD_FORMAT_NONE;
 324
 325         dasd_info->features |=
 326                 ((base->features & DASD_FEATURE_READONLY) != 0);
 327
 328         memcpy(dasd_info->type, base->discipline->name, 4);
 329
 330         if (block->request_queue->request_fn) {
 331                 struct list_head *l;
 332 #ifdef DASD_EXTENDED_PROFILING
 333                 {
 334                         struct list_head *l;
 335                         spin_lock_irqsave(&block->lock, flags);
 336                         list_for_each(l, &block->request_queue->queue_head)
 337                                 dasd_info->req_queue_len++;
 338                         spin_unlock_irqrestore(&block->lock, flags);
 339                 }
 340 #endif                          /* DASD_EXTENDED_PROFILING */
 341                 spin_lock_irqsave(get_ccwdev_lock(base->cdev), flags);
 342                 list_for_each(l, &base->ccw_queue)
 343                         dasd_info->chanq_len++;
 344                 spin_unlock_irqrestore(get_ccwdev_lock(base->cdev),
 345                                        flags);
 346         }
 347
 348         rc = 0;
 349         if (copy_to_user(argp, dasd_info,
 350                          ((cmd == (unsigned int) BIODASDINFO2) ?
 351                           sizeof(struct dasd_information2_t) :
 352                           sizeof(struct dasd_information_t))))
 353                 rc = -EFAULT;
 354         kfree(dasd_info);
 355         return rc;
 356 }
 357
 358 /*
 359  * Set read only
 360  */
 361 static int
 362 dasd_ioctl_set_ro(struct block_device *bdev, void __user *argp)
 363 {
 364         struct dasd_device *base;
 365         int intval, rc;
 366
 367         if (!capable(CAP_SYS_ADMIN))
 368                 return -EACCES;
 369         if (bdev != bdev->bd_contains)
 370                 // ro setting is not allowed for partitions
 371                 return -EINVAL;
 372         if (get_user(intval, (int __user *)argp))
 373                 return -EFAULT;
 374         base = dasd_device_from_gendisk(bdev->bd_disk);
 375         if (!base)
 376                 return -ENODEV;
 377         if (!intval && test_bit(DASD_FLAG_DEVICE_RO, &base->flags)) {
 378                 dasd_put_device(base);
 379                 return -EROFS;
 380         }
 381         set_disk_ro(bdev->bd_disk, intval);
 382         rc = dasd_set_feature(base->cdev, DASD_FEATURE_READONLY, intval);
 383         dasd_put_device(base);
 384         return rc;
 385 }
 386
 387 static int dasd_ioctl_readall_cmb(struct dasd_block *block, unsigned int cmd,
 388                                   struct cmbdata __user *argp)
 389 {
 390         size_t size = _IOC_SIZE(cmd);
 391         struct cmbdata data;
 392         int ret;
 393
 394         ret = cmf_readall(block->base->cdev, &data);
 395         if (!ret && copy_to_user(argp, &data, min(size, sizeof(*argp))))
 396                 return -EFAULT;
 397         return ret;
 398 }
 399
 400 int dasd_ioctl(struct block_device *bdev, fmode_t mode,
 401                unsigned int cmd, unsigned long arg)
 402 {
 403         struct dasd_block *block;
 404         struct dasd_device *base;
 405         void __user *argp;
 406         int rc;
 407
 408         if (is_compat_task())
 409                 argp = compat_ptr(arg);
 410         else
 411                 argp = (void __user *)arg;
 412
 413         if ((_IOC_DIR(cmd) != _IOC_NONE) && !arg) {
 414                 PRINT_DEBUG("empty data ptr");
 415                 return -EINVAL;
 416         }
 417
 418         base = dasd_device_from_gendisk(bdev->bd_disk);
 419         if (!base)
 420                 return -ENODEV;
 421         block = base->block;
 422         rc = 0;
 423         switch (cmd) {
 424         case BIODASDDISABLE:
 425                 rc = dasd_ioctl_disable(bdev);
 426                 break;
 427         case BIODASDENABLE:
 428                 rc = dasd_ioctl_enable(bdev);
 429                 break;
 430         case BIODASDQUIESCE:
 431                 rc = dasd_ioctl_quiesce(block);
 432                 break;
 433         case BIODASDRESUME:
 434                 rc = dasd_ioctl_resume(block);
 435                 break;
 436         case BIODASDFMT:
 437                 rc = dasd_ioctl_format(bdev, argp);
 438                 break;
 439         case BIODASDINFO:
 440                 rc = dasd_ioctl_information(block, cmd, argp);
 441                 break;
 442         case BIODASDINFO2:
 443                 rc = dasd_ioctl_information(block, cmd, argp);
 444                 break;
 445         case BIODASDPRRD:
 446                 rc = dasd_ioctl_read_profile(block, argp);
 447                 break;
 448         case BIODASDPRRST:
 449                 rc = dasd_ioctl_reset_profile(block);
 450                 break;
 451         case BLKROSET:
 452                 rc = dasd_ioctl_set_ro(bdev, argp);
 453                 break;
 454         case DASDAPIVER:
 455                 rc = dasd_ioctl_api_version(argp);
 456                 break;
 457         case BIODASDCMFENABLE:
 458                 rc = enable_cmf(base->cdev);
 459                 break;
 460         case BIODASDCMFDISABLE:
 461                 rc = disable_cmf(base->cdev);
 462                 break;
 463         case BIODASDREADALLCMB:
 464                 rc = dasd_ioctl_readall_cmb(block, cmd, argp);
 465                 break;
 466         default:
 467                 /* if the discipline has an ioctl method try it. */
 468                 if (base->discipline->ioctl) {
 469                         rc = base->discipline->ioctl(block, cmd, argp);
 470                         if (rc == -ENOIOCTLCMD)
 471                                 rc = -EINVAL;
 472                 } else
 473                         rc = -EINVAL;
 474         }
 475         dasd_put_device(base);
 476         return rc;
 477 }