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