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