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