drivers/s390/block/dasd_ioctl.c

   1 /*
   2  * Author(s)......: Holger Smolinski <Holger.Smolinski@de.ibm.com>
   3  *                  Horst Hummel <Horst.Hummel@de.ibm.com>
   4  *                  Carsten Otte <Cotte@de.ibm.com>
   5  *                  Martin Schwidefsky <schwidefsky@de.ibm.com>
   6  * Bugreports.to..: <Linux390@de.ibm.com>
   7  * Copyright IBM Corp. 1999, 2001
   8  *
   9  * i/o controls for the dasd driver.
  10  */
  11
  12 #define KMSG_COMPONENT "dasd"
  13
  14 #include <linux/interrupt.h>
  15 #include <linux/compat.h>
  16 #include <linux/major.h>
  17 #include <linux/fs.h>
  18 #include <linux/blkpg.h>
  19 #include <linux/slab.h>
  20 #include <asm/compat.h>
  21 #include <asm/ccwdev.h>
  22 #include <asm/schid.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 multiple units of the device. In terms of the ECKD
 147  * devices this means CCWs are generated to format multiple tracks.
 148  */
 149 static int
 150 dasd_format(struct dasd_block *block, struct format_data_t *fdata)
 151 {
 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_warn("%s: The DASD cannot be formatted while it is enabled\n",
 161                         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         rc = base->discipline->format_device(base, fdata);
 182         if (rc)
 183                 return rc;
 184
 185         return 0;
 186 }
 187
 188 /*
 189  * Format device.
 190  */
 191 static int
 192 dasd_ioctl_format(struct block_device *bdev, void __user *argp)
 193 {
 194         struct dasd_device *base;
 195         struct format_data_t fdata;
 196         int rc;
 197
 198         if (!capable(CAP_SYS_ADMIN))
 199                 return -EACCES;
 200         if (!argp)
 201                 return -EINVAL;
 202         base = dasd_device_from_gendisk(bdev->bd_disk);
 203         if (!base)
 204                 return -ENODEV;
 205         if (base->features & DASD_FEATURE_READONLY ||
 206             test_bit(DASD_FLAG_DEVICE_RO, &base->flags)) {
 207                 dasd_put_device(base);
 208                 return -EROFS;
 209         }
 210         if (copy_from_user(&fdata, argp, sizeof(struct format_data_t))) {
 211                 dasd_put_device(base);
 212                 return -EFAULT;
 213         }
 214         if (bdev != bdev->bd_contains) {
 215                 pr_warning("%s: The specified DASD is a partition and cannot "
 216                            "be formatted\n",
 217                            dev_name(&base->cdev->dev));
 218                 dasd_put_device(base);
 219                 return -EINVAL;
 220         }
 221         rc = dasd_format(base->block, &fdata);
 222         dasd_put_device(base);
 223         return rc;
 224 }
 225
 226 #ifdef CONFIG_DASD_PROFILE
 227 /*
 228  * Reset device profile information
 229  */
 230 static int dasd_ioctl_reset_profile(struct dasd_block *block)
 231 {
 232         dasd_profile_reset(&block->profile);
 233         return 0;
 234 }
 235
 236 /*
 237  * Return device profile information
 238  */
 239 static int dasd_ioctl_read_profile(struct dasd_block *block, void __user *argp)
 240 {
 241         struct dasd_profile_info_t *data;
 242         int rc = 0;
 243
 244         data = kmalloc(sizeof(*data), GFP_KERNEL);
 245         if (!data)
 246                 return -ENOMEM;
 247
 248         spin_lock_bh(&block->profile.lock);
 249         if (block->profile.data) {
 250                 data->dasd_io_reqs = block->profile.data->dasd_io_reqs;
 251                 data->dasd_io_sects = block->profile.data->dasd_io_sects;
 252                 memcpy(data->dasd_io_secs, block->profile.data->dasd_io_secs,
 253                        sizeof(data->dasd_io_secs));
 254                 memcpy(data->dasd_io_times, block->profile.data->dasd_io_times,
 255                        sizeof(data->dasd_io_times));
 256                 memcpy(data->dasd_io_timps, block->profile.data->dasd_io_timps,
 257                        sizeof(data->dasd_io_timps));
 258                 memcpy(data->dasd_io_time1, block->profile.data->dasd_io_time1,
 259                        sizeof(data->dasd_io_time1));
 260                 memcpy(data->dasd_io_time2, block->profile.data->dasd_io_time2,
 261                        sizeof(data->dasd_io_time2));
 262                 memcpy(data->dasd_io_time2ps,
 263                        block->profile.data->dasd_io_time2ps,
 264                        sizeof(data->dasd_io_time2ps));
 265                 memcpy(data->dasd_io_time3, block->profile.data->dasd_io_time3,
 266                        sizeof(data->dasd_io_time3));
 267                 memcpy(data->dasd_io_nr_req,
 268                        block->profile.data->dasd_io_nr_req,
 269                        sizeof(data->dasd_io_nr_req));
 270                 spin_unlock_bh(&block->profile.lock);
 271         } else {
 272                 spin_unlock_bh(&block->profile.lock);
 273                 rc = -EIO;
 274                 goto out;
 275         }
 276         if (copy_to_user(argp, data, sizeof(*data)))
 277                 rc = -EFAULT;
 278 out:
 279         kfree(data);
 280         return rc;
 281 }
 282 #else
 283 static int dasd_ioctl_reset_profile(struct dasd_block *block)
 284 {
 285         return -ENOTTY;
 286 }
 287
 288 static int dasd_ioctl_read_profile(struct dasd_block *block, void __user *argp)
 289 {
 290         return -ENOTTY;
 291 }
 292 #endif
 293
 294 /*
 295  * Return dasd information. Used for BIODASDINFO and BIODASDINFO2.
 296  */
 297 static int dasd_ioctl_information(struct dasd_block *block,
 298                                   unsigned int cmd, void __user *argp)
 299 {
 300         struct dasd_information2_t *dasd_info;
 301         struct subchannel_id sch_id;
 302         struct ccw_dev_id dev_id;
 303         struct dasd_device *base;
 304         struct ccw_device *cdev;
 305         unsigned long flags;
 306         int rc;
 307
 308         base = block->base;
 309         if (!base->discipline || !base->discipline->fill_info)
 310                 return -EINVAL;
 311
 312         dasd_info = kzalloc(sizeof(struct dasd_information2_t), GFP_KERNEL);
 313         if (dasd_info == NULL)
 314                 return -ENOMEM;
 315
 316         rc = base->discipline->fill_info(base, dasd_info);
 317         if (rc) {
 318                 kfree(dasd_info);
 319                 return rc;
 320         }
 321
 322         cdev = base->cdev;
 323         ccw_device_get_id(cdev, &dev_id);
 324         ccw_device_get_schid(cdev, &sch_id);
 325
 326         dasd_info->devno = dev_id.devno;
 327         dasd_info->schid = sch_id.sch_no;
 328         dasd_info->cu_type = cdev->id.cu_type;
 329         dasd_info->cu_model = cdev->id.cu_model;
 330         dasd_info->dev_type = cdev->id.dev_type;
 331         dasd_info->dev_model = cdev->id.dev_model;
 332         dasd_info->status = base->state;
 333         /*
 334          * The open_count is increased for every opener, that includes
 335          * the blkdev_get in dasd_scan_partitions.
 336          * This must be hidden from user-space.
 337          */
 338         dasd_info->open_count = atomic_read(&block->open_count);
 339         if (!block->bdev)
 340                 dasd_info->open_count++;
 341
 342         /*
 343          * check if device is really formatted
 344          * LDL / CDL was returned by 'fill_info'
 345          */
 346         if ((base->state < DASD_STATE_READY) ||
 347             (dasd_check_blocksize(block->bp_block)))
 348                 dasd_info->format = DASD_FORMAT_NONE;
 349
 350         dasd_info->features |=
 351                 ((base->features & DASD_FEATURE_READONLY) != 0);
 352
 353         memcpy(dasd_info->type, base->discipline->name, 4);
 354
 355         if (block->request_queue->request_fn) {
 356                 struct list_head *l;
 357 #ifdef DASD_EXTENDED_PROFILING
 358                 {
 359                         struct list_head *l;
 360                         spin_lock_irqsave(&block->lock, flags);
 361                         list_for_each(l, &block->request_queue->queue_head)
 362                                 dasd_info->req_queue_len++;
 363                         spin_unlock_irqrestore(&block->lock, flags);
 364                 }
 365 #endif                          /* DASD_EXTENDED_PROFILING */
 366                 spin_lock_irqsave(get_ccwdev_lock(base->cdev), flags);
 367                 list_for_each(l, &base->ccw_queue)
 368                         dasd_info->chanq_len++;
 369                 spin_unlock_irqrestore(get_ccwdev_lock(base->cdev),
 370                                        flags);
 371         }
 372
 373         rc = 0;
 374         if (copy_to_user(argp, dasd_info,
 375                          ((cmd == (unsigned int) BIODASDINFO2) ?
 376                           sizeof(struct dasd_information2_t) :
 377                           sizeof(struct dasd_information_t))))
 378                 rc = -EFAULT;
 379         kfree(dasd_info);
 380         return rc;
 381 }
 382
 383 /*
 384  * Set read only
 385  */
 386 static int
 387 dasd_ioctl_set_ro(struct block_device *bdev, void __user *argp)
 388 {
 389         struct dasd_device *base;
 390         int intval, rc;
 391
 392         if (!capable(CAP_SYS_ADMIN))
 393                 return -EACCES;
 394         if (bdev != bdev->bd_contains)
 395                 // ro setting is not allowed for partitions
 396                 return -EINVAL;
 397         if (get_user(intval, (int __user *)argp))
 398                 return -EFAULT;
 399         base = dasd_device_from_gendisk(bdev->bd_disk);
 400         if (!base)
 401                 return -ENODEV;
 402         if (!intval && test_bit(DASD_FLAG_DEVICE_RO, &base->flags)) {
 403                 dasd_put_device(base);
 404                 return -EROFS;
 405         }
 406         set_disk_ro(bdev->bd_disk, intval);
 407         rc = dasd_set_feature(base->cdev, DASD_FEATURE_READONLY, intval);
 408         dasd_put_device(base);
 409         return rc;
 410 }
 411
 412 static int dasd_ioctl_readall_cmb(struct dasd_block *block, unsigned int cmd,
 413                                   struct cmbdata __user *argp)
 414 {
 415         size_t size = _IOC_SIZE(cmd);
 416         struct cmbdata data;
 417         int ret;
 418
 419         ret = cmf_readall(block->base->cdev, &data);
 420         if (!ret && copy_to_user(argp, &data, min(size, sizeof(*argp))))
 421                 return -EFAULT;
 422         return ret;
 423 }
 424
 425 int dasd_ioctl(struct block_device *bdev, fmode_t mode,
 426                unsigned int cmd, unsigned long arg)
 427 {
 428         struct dasd_block *block;
 429         struct dasd_device *base;
 430         void __user *argp;
 431         int rc;
 432
 433         if (is_compat_task())
 434                 argp = compat_ptr(arg);
 435         else
 436                 argp = (void __user *)arg;
 437
 438         if ((_IOC_DIR(cmd) != _IOC_NONE) && !arg) {
 439                 PRINT_DEBUG("empty data ptr");
 440                 return -EINVAL;
 441         }
 442
 443         base = dasd_device_from_gendisk(bdev->bd_disk);
 444         if (!base)
 445                 return -ENODEV;
 446         block = base->block;
 447         rc = 0;
 448         switch (cmd) {
 449         case BIODASDDISABLE:
 450                 rc = dasd_ioctl_disable(bdev);
 451                 break;
 452         case BIODASDENABLE:
 453                 rc = dasd_ioctl_enable(bdev);
 454                 break;
 455         case BIODASDQUIESCE:
 456                 rc = dasd_ioctl_quiesce(block);
 457                 break;
 458         case BIODASDRESUME:
 459                 rc = dasd_ioctl_resume(block);
 460                 break;
 461         case BIODASDFMT:
 462                 rc = dasd_ioctl_format(bdev, argp);
 463                 break;
 464         case BIODASDINFO:
 465                 rc = dasd_ioctl_information(block, cmd, argp);
 466                 break;
 467         case BIODASDINFO2:
 468                 rc = dasd_ioctl_information(block, cmd, argp);
 469                 break;
 470         case BIODASDPRRD:
 471                 rc = dasd_ioctl_read_profile(block, argp);
 472                 break;
 473         case BIODASDPRRST:
 474                 rc = dasd_ioctl_reset_profile(block);
 475                 break;
 476         case BLKROSET:
 477                 rc = dasd_ioctl_set_ro(bdev, argp);
 478                 break;
 479         case DASDAPIVER:
 480                 rc = dasd_ioctl_api_version(argp);
 481                 break;
 482         case BIODASDCMFENABLE:
 483                 rc = enable_cmf(base->cdev);
 484                 break;
 485         case BIODASDCMFDISABLE:
 486                 rc = disable_cmf(base->cdev);
 487                 break;
 488         case BIODASDREADALLCMB:
 489                 rc = dasd_ioctl_readall_cmb(block, cmd, argp);
 490                 break;
 491         default:
 492                 /* if the discipline has an ioctl method try it. */
 493                 rc = -ENOTTY;
 494                 if (base->discipline->ioctl)
 495                         rc = base->discipline->ioctl(block, cmd, argp);
 496         }
 497         dasd_put_device(base);
 498         return rc;
 499 }