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         dasd_profile_reset(&block->profile);
 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         struct dasd_profile_info_t *data;
 253         int rc = 0;
 254
 255         data = kmalloc(sizeof(*data), GFP_KERNEL);
 256         if (!data)
 257                 return -ENOMEM;
 258
 259         spin_lock_bh(&block->profile.lock);
 260         if (block->profile.data) {
 261                 data->dasd_io_reqs = block->profile.data->dasd_io_reqs;
 262                 data->dasd_io_sects = block->profile.data->dasd_io_sects;
 263                 memcpy(data->dasd_io_secs, block->profile.data->dasd_io_secs,
 264                        sizeof(data->dasd_io_secs));
 265                 memcpy(data->dasd_io_times, block->profile.data->dasd_io_times,
 266                        sizeof(data->dasd_io_times));
 267                 memcpy(data->dasd_io_timps, block->profile.data->dasd_io_timps,
 268                        sizeof(data->dasd_io_timps));
 269                 memcpy(data->dasd_io_time1, block->profile.data->dasd_io_time1,
 270                        sizeof(data->dasd_io_time1));
 271                 memcpy(data->dasd_io_time2, block->profile.data->dasd_io_time2,
 272                        sizeof(data->dasd_io_time2));
 273                 memcpy(data->dasd_io_time2ps,
 274                        block->profile.data->dasd_io_time2ps,
 275                        sizeof(data->dasd_io_time2ps));
 276                 memcpy(data->dasd_io_time3, block->profile.data->dasd_io_time3,
 277                        sizeof(data->dasd_io_time3));
 278                 memcpy(data->dasd_io_nr_req,
 279                        block->profile.data->dasd_io_nr_req,
 280                        sizeof(data->dasd_io_nr_req));
 281                 spin_unlock_bh(&block->profile.lock);
 282         } else {
 283                 spin_unlock_bh(&block->profile.lock);
 284                 rc = -EIO;
 285                 goto out;
 286         }
 287         if (copy_to_user(argp, data, sizeof(*data)))
 288                 rc = -EFAULT;
 289 out:
 290         kfree(data);
 291         return rc;
 292 }
 293 #else
 294 static int dasd_ioctl_reset_profile(struct dasd_block *block)
 295 {
 296         return -ENOSYS;
 297 }
 298
 299 static int dasd_ioctl_read_profile(struct dasd_block *block, void __user *argp)
 300 {
 301         return -ENOSYS;
 302 }
 303 #endif
 304
 305 /*
 306  * Return dasd information. Used for BIODASDINFO and BIODASDINFO2.
 307  */
 308 static int dasd_ioctl_information(struct dasd_block *block,
 309                                   unsigned int cmd, void __user *argp)
 310 {
 311         struct dasd_information2_t *dasd_info;
 312         unsigned long flags;
 313         int rc;
 314         struct dasd_device *base;
 315         struct ccw_device *cdev;
 316         struct ccw_dev_id dev_id;
 317
 318         base = block->base;
 319         if (!base->discipline || !base->discipline->fill_info)
 320                 return -EINVAL;
 321
 322         dasd_info = kzalloc(sizeof(struct dasd_information2_t), GFP_KERNEL);
 323         if (dasd_info == NULL)
 324                 return -ENOMEM;
 325
 326         rc = base->discipline->fill_info(base, dasd_info);
 327         if (rc) {
 328                 kfree(dasd_info);
 329                 return rc;
 330         }
 331
 332         cdev = base->cdev;
 333         ccw_device_get_id(cdev, &dev_id);
 334
 335         dasd_info->devno = dev_id.devno;
 336         dasd_info->schid = _ccw_device_get_subchannel_number(base->cdev);
 337         dasd_info->cu_type = cdev->id.cu_type;
 338         dasd_info->cu_model = cdev->id.cu_model;
 339         dasd_info->dev_type = cdev->id.dev_type;
 340         dasd_info->dev_model = cdev->id.dev_model;
 341         dasd_info->status = base->state;
 342         /*
 343          * The open_count is increased for every opener, that includes
 344          * the blkdev_get in dasd_scan_partitions.
 345          * This must be hidden from user-space.
 346          */
 347         dasd_info->open_count = atomic_read(&block->open_count);
 348         if (!block->bdev)
 349                 dasd_info->open_count++;
 350
 351         /*
 352          * check if device is really formatted
 353          * LDL / CDL was returned by 'fill_info'
 354          */
 355         if ((base->state < DASD_STATE_READY) ||
 356             (dasd_check_blocksize(block->bp_block)))
 357                 dasd_info->format = DASD_FORMAT_NONE;
 358
 359         dasd_info->features |=
 360                 ((base->features & DASD_FEATURE_READONLY) != 0);
 361
 362         memcpy(dasd_info->type, base->discipline->name, 4);
 363
 364         if (block->request_queue->request_fn) {
 365                 struct list_head *l;
 366 #ifdef DASD_EXTENDED_PROFILING
 367                 {
 368                         struct list_head *l;
 369                         spin_lock_irqsave(&block->lock, flags);
 370                         list_for_each(l, &block->request_queue->queue_head)
 371                                 dasd_info->req_queue_len++;
 372                         spin_unlock_irqrestore(&block->lock, flags);
 373                 }
 374 #endif                          /* DASD_EXTENDED_PROFILING */
 375                 spin_lock_irqsave(get_ccwdev_lock(base->cdev), flags);
 376                 list_for_each(l, &base->ccw_queue)
 377                         dasd_info->chanq_len++;
 378                 spin_unlock_irqrestore(get_ccwdev_lock(base->cdev),
 379                                        flags);
 380         }
 381
 382         rc = 0;
 383         if (copy_to_user(argp, dasd_info,
 384                          ((cmd == (unsigned int) BIODASDINFO2) ?
 385                           sizeof(struct dasd_information2_t) :
 386                           sizeof(struct dasd_information_t))))
 387                 rc = -EFAULT;
 388         kfree(dasd_info);
 389         return rc;
 390 }
 391
 392 /*
 393  * Set read only
 394  */
 395 static int
 396 dasd_ioctl_set_ro(struct block_device *bdev, void __user *argp)
 397 {
 398         struct dasd_device *base;
 399         int intval, rc;
 400
 401         if (!capable(CAP_SYS_ADMIN))
 402                 return -EACCES;
 403         if (bdev != bdev->bd_contains)
 404                 // ro setting is not allowed for partitions
 405                 return -EINVAL;
 406         if (get_user(intval, (int __user *)argp))
 407                 return -EFAULT;
 408         base = dasd_device_from_gendisk(bdev->bd_disk);
 409         if (!base)
 410                 return -ENODEV;
 411         if (!intval && test_bit(DASD_FLAG_DEVICE_RO, &base->flags)) {
 412                 dasd_put_device(base);
 413                 return -EROFS;
 414         }
 415         set_disk_ro(bdev->bd_disk, intval);
 416         rc = dasd_set_feature(base->cdev, DASD_FEATURE_READONLY, intval);
 417         dasd_put_device(base);
 418         return rc;
 419 }
 420
 421 static int dasd_ioctl_readall_cmb(struct dasd_block *block, unsigned int cmd,
 422                                   struct cmbdata __user *argp)
 423 {
 424         size_t size = _IOC_SIZE(cmd);
 425         struct cmbdata data;
 426         int ret;
 427
 428         ret = cmf_readall(block->base->cdev, &data);
 429         if (!ret && copy_to_user(argp, &data, min(size, sizeof(*argp))))
 430                 return -EFAULT;
 431         return ret;
 432 }
 433
 434 int dasd_ioctl(struct block_device *bdev, fmode_t mode,
 435                unsigned int cmd, unsigned long arg)
 436 {
 437         struct dasd_block *block;
 438         struct dasd_device *base;
 439         void __user *argp;
 440         int rc;
 441
 442         if (is_compat_task())
 443                 argp = compat_ptr(arg);
 444         else
 445                 argp = (void __user *)arg;
 446
 447         if ((_IOC_DIR(cmd) != _IOC_NONE) && !arg) {
 448                 PRINT_DEBUG("empty data ptr");
 449                 return -EINVAL;
 450         }
 451
 452         base = dasd_device_from_gendisk(bdev->bd_disk);
 453         if (!base)
 454                 return -ENODEV;
 455         block = base->block;
 456         rc = 0;
 457         switch (cmd) {
 458         case BIODASDDISABLE:
 459                 rc = dasd_ioctl_disable(bdev);
 460                 break;
 461         case BIODASDENABLE:
 462                 rc = dasd_ioctl_enable(bdev);
 463                 break;
 464         case BIODASDQUIESCE:
 465                 rc = dasd_ioctl_quiesce(block);
 466                 break;
 467         case BIODASDRESUME:
 468                 rc = dasd_ioctl_resume(block);
 469                 break;
 470         case BIODASDFMT:
 471                 rc = dasd_ioctl_format(bdev, argp);
 472                 break;
 473         case BIODASDINFO:
 474                 rc = dasd_ioctl_information(block, cmd, argp);
 475                 break;
 476         case BIODASDINFO2:
 477                 rc = dasd_ioctl_information(block, cmd, argp);
 478                 break;
 479         case BIODASDPRRD:
 480                 rc = dasd_ioctl_read_profile(block, argp);
 481                 break;
 482         case BIODASDPRRST:
 483                 rc = dasd_ioctl_reset_profile(block);
 484                 break;
 485         case BLKROSET:
 486                 rc = dasd_ioctl_set_ro(bdev, argp);
 487                 break;
 488         case DASDAPIVER:
 489                 rc = dasd_ioctl_api_version(argp);
 490                 break;
 491         case BIODASDCMFENABLE:
 492                 rc = enable_cmf(base->cdev);
 493                 break;
 494         case BIODASDCMFDISABLE:
 495                 rc = disable_cmf(base->cdev);
 496                 break;
 497         case BIODASDREADALLCMB:
 498                 rc = dasd_ioctl_readall_cmb(block, cmd, argp);
 499                 break;
 500         default:
 501                 /* if the discipline has an ioctl method try it. */
 502                 if (base->discipline->ioctl) {
 503                         rc = base->discipline->ioctl(block, cmd, argp);
 504                         if (rc == -ENOIOCTLCMD)
 505                                 rc = -EINVAL;
 506                 } else
 507                         rc = -EINVAL;
 508         }
 509         dasd_put_device(base);
 510         return rc;
 511 }