include/linux/genhd.h

   1 #ifndef _LINUX_GENHD_H
   2 #define _LINUX_GENHD_H
   3
   4 /*
   5  *      genhd.h Copyright (C) 1992 Drew Eckhardt
   6  *      Generic hard disk header file by
   7  *              Drew Eckhardt
   8  *
   9  *              <drew@colorado.edu>
  10  */
  11
  12 #include <linux/types.h>
  13 #include <linux/kdev_t.h>
  14 #include <linux/rcupdate.h>
  15
  16 #ifdef CONFIG_BLOCK
  17
  18 #define kobj_to_dev(k) container_of(k, struct device, kobj)
  19 #define dev_to_disk(device) container_of(device, struct gendisk, dev)
  20 #define dev_to_part(device) container_of(device, struct hd_struct, dev)
  21
  22 extern struct device_type part_type;
  23 extern struct kobject *block_depr;
  24 extern struct class block_class;
  25
  26 extern const struct seq_operations partitions_op;
  27 extern const struct seq_operations diskstats_op;
  28
  29 enum {
  30 /* These three have identical behaviour; use the second one if DOS FDISK gets
  31    confused about extended/logical partitions starting past cylinder 1023. */
  32         DOS_EXTENDED_PARTITION = 5,
  33         LINUX_EXTENDED_PARTITION = 0x85,
  34         WIN98_EXTENDED_PARTITION = 0x0f,
  35
  36         SUN_WHOLE_DISK = DOS_EXTENDED_PARTITION,
  37
  38         LINUX_SWAP_PARTITION = 0x82,
  39         LINUX_DATA_PARTITION = 0x83,
  40         LINUX_LVM_PARTITION = 0x8e,
  41         LINUX_RAID_PARTITION = 0xfd,    /* autodetect RAID partition */
  42
  43         SOLARIS_X86_PARTITION = LINUX_SWAP_PARTITION,
  44         NEW_SOLARIS_X86_PARTITION = 0xbf,
  45
  46         DM6_AUX1PARTITION = 0x51,       /* no DDO:  use xlated geom */
  47         DM6_AUX3PARTITION = 0x53,       /* no DDO:  use xlated geom */
  48         DM6_PARTITION = 0x54,           /* has DDO: use xlated geom & offset */
  49         EZD_PARTITION = 0x55,           /* EZ-DRIVE */
  50
  51         FREEBSD_PARTITION = 0xa5,       /* FreeBSD Partition ID */
  52         OPENBSD_PARTITION = 0xa6,       /* OpenBSD Partition ID */
  53         NETBSD_PARTITION = 0xa9,        /* NetBSD Partition ID */
  54         BSDI_PARTITION = 0xb7,          /* BSDI Partition ID */
  55         MINIX_PARTITION = 0x81,         /* Minix Partition ID */
  56         UNIXWARE_PARTITION = 0x63,      /* Same as GNU_HURD and SCO Unix */
  57 };
  58
  59 #include <linux/major.h>
  60 #include <linux/device.h>
  61 #include <linux/smp.h>
  62 #include <linux/string.h>
  63 #include <linux/fs.h>
  64 #include <linux/workqueue.h>
  65
  66 struct partition {
  67         unsigned char boot_ind;         /* 0x80 - active */
  68         unsigned char head;             /* starting head */
  69         unsigned char sector;           /* starting sector */
  70         unsigned char cyl;              /* starting cylinder */
  71         unsigned char sys_ind;          /* What partition type */
  72         unsigned char end_head;         /* end head */
  73         unsigned char end_sector;       /* end sector */
  74         unsigned char end_cyl;          /* end cylinder */
  75         __le32 start_sect;      /* starting sector counting from 0 */
  76         __le32 nr_sects;                /* nr of sectors in partition */
  77 } __attribute__((packed));
  78
  79 struct disk_stats {
  80         unsigned long sectors[2];       /* READs and WRITEs */
  81         unsigned long ios[2];
  82         unsigned long merges[2];
  83         unsigned long ticks[2];
  84         unsigned long io_ticks;
  85         unsigned long time_in_queue;
  86 };
  87
  88 struct hd_struct {
  89         sector_t start_sect;
  90         sector_t nr_sects;
  91         struct device dev;
  92         struct kobject *holder_dir;
  93         int policy, partno;
  94 #ifdef CONFIG_FAIL_MAKE_REQUEST
  95         int make_it_fail;
  96 #endif
  97         unsigned long stamp;
  98         int in_flight;
  99 #ifdef  CONFIG_SMP
 100         struct disk_stats *dkstats;
 101 #else
 102         struct disk_stats dkstats;
 103 #endif
 104         struct rcu_head rcu_head;
 105 };
 106
 107 #define GENHD_FL_REMOVABLE                      1
 108 #define GENHD_FL_DRIVERFS                       2
 109 #define GENHD_FL_MEDIA_CHANGE_NOTIFY            4
 110 #define GENHD_FL_CD                             8
 111 #define GENHD_FL_UP                             16
 112 #define GENHD_FL_SUPPRESS_PARTITION_INFO        32
 113 #define GENHD_FL_FAIL                           64
 114
 115 struct gendisk {
 116         /* major, first_minor and minors are input parameters only,
 117          * don't use directly.  Use disk_devt() and disk_max_parts().
 118          */
 119         int major;                      /* major number of driver */
 120         int first_minor;
 121         int minors;                     /* maximum number of minors, =1 for
 122                                          * disks that can't be partitioned. */
 123
 124         char disk_name[32];             /* name of major driver */
 125
 126         /* Array of pointers to partitions indexed by partno - 1.
 127          * Protected with matching bdev lock but stat and other
 128          * non-critical accesses use RCU.  Always access through
 129          * helpers.
 130          */
 131         struct hd_struct **__part;
 132
 133         struct block_device_operations *fops;
 134         struct request_queue *queue;
 135         void *private_data;
 136         sector_t capacity;
 137
 138         int flags;
 139         struct device *driverfs_dev;  // FIXME: remove
 140         struct device dev;
 141         struct kobject *holder_dir;
 142         struct kobject *slave_dir;
 143
 144         struct timer_rand_state *random;
 145         int policy;
 146
 147         atomic_t sync_io;               /* RAID */
 148         unsigned long stamp;
 149         int in_flight;
 150 #ifdef  CONFIG_SMP
 151         struct disk_stats *dkstats;
 152 #else
 153         struct disk_stats dkstats;
 154 #endif
 155         struct work_struct async_notify;
 156 #ifdef  CONFIG_BLK_DEV_INTEGRITY
 157         struct blk_integrity *integrity;
 158 #endif
 159 };
 160
 161 static inline struct gendisk *part_to_disk(struct hd_struct *part)
 162 {
 163         if (likely(part))
 164                 return dev_to_disk((part)->dev.parent);
 165         return NULL;
 166 }
 167
 168 static inline int disk_max_parts(struct gendisk *disk)
 169 {
 170         return disk->minors - 1;
 171 }
 172
 173 static inline dev_t disk_devt(struct gendisk *disk)
 174 {
 175         return disk->dev.devt;
 176 }
 177
 178 static inline dev_t part_devt(struct hd_struct *part)
 179 {
 180         return part->dev.devt;
 181 }
 182
 183 extern struct hd_struct *disk_get_part(struct gendisk *disk, int partno);
 184
 185 static inline void disk_put_part(struct hd_struct *part)
 186 {
 187         if (likely(part))
 188                 put_device(&part->dev);
 189 }
 190
 191 /*
 192  * Smarter partition iterator without context limits.
 193  */
 194 #define DISK_PITER_REVERSE      (1 << 0) /* iterate in the reverse direction */
 195 #define DISK_PITER_INCL_EMPTY   (1 << 1) /* include 0-sized parts */
 196
 197 struct disk_part_iter {
 198         struct gendisk          *disk;
 199         struct hd_struct        *part;
 200         int                     idx;
 201         unsigned int            flags;
 202 };
 203
 204 extern void disk_part_iter_init(struct disk_part_iter *piter,
 205                                  struct gendisk *disk, unsigned int flags);
 206 extern struct hd_struct *disk_part_iter_next(struct disk_part_iter *piter);
 207 extern void disk_part_iter_exit(struct disk_part_iter *piter);
 208
 209 extern struct hd_struct *disk_map_sector_rcu(struct gendisk *disk,
 210                                              sector_t sector);
 211
 212 /*
 213  * Macros to operate on percpu disk statistics:
 214  *
 215  * {disk|part|all}_stat_{add|sub|inc|dec}() modify the stat counters
 216  * and should be called between disk_stat_lock() and
 217  * disk_stat_unlock().
 218  *
 219  * part_stat_read() can be called at any time.
 220  *
 221  * part_stat_{add|set_all}() and {init|free}_part_stats are for
 222  * internal use only.
 223  */
 224 #ifdef  CONFIG_SMP
 225 #define disk_stat_lock()        ({ rcu_read_lock(); get_cpu(); })
 226 #define disk_stat_unlock()      do { put_cpu(); rcu_read_unlock(); } while (0)
 227
 228 #define disk_stat_add(cpu, gendiskp, field, addnd)                      \
 229         (per_cpu_ptr(gendiskp->dkstats, cpu)->field += addnd)
 230
 231 #define disk_stat_read(gendiskp, field)                                 \
 232 ({                                                                      \
 233         typeof(gendiskp->dkstats->field) res = 0;                       \
 234         int i;                                                          \
 235         for_each_possible_cpu(i)                                        \
 236                 res += per_cpu_ptr(gendiskp->dkstats, i)->field;        \
 237         res;                                                            \
 238 })
 239
 240 static inline void disk_stat_set_all(struct gendisk *gendiskp, int value)
 241 {
 242         int i;
 243
 244         for_each_possible_cpu(i)
 245                 memset(per_cpu_ptr(gendiskp->dkstats, i), value,
 246                                 sizeof(struct disk_stats));
 247 }
 248
 249 #define part_stat_add(cpu, part, field, addnd)                          \
 250         (per_cpu_ptr(part->dkstats, cpu)->field += addnd)
 251
 252 #define all_stat_add(cpu, gendiskp, part, field, addnd, sector)         \
 253 ({                                                                      \
 254         if (part)                                                       \
 255                 part_stat_add(cpu, part, field, addnd);                 \
 256         disk_stat_add(cpu, gendiskp, field, addnd);                     \
 257 })
 258
 259 #define part_stat_read(part, field)                                     \
 260 ({                                                                      \
 261         typeof(part->dkstats->field) res = 0;                           \
 262         int i;                                                          \
 263         for_each_possible_cpu(i)                                        \
 264                 res += per_cpu_ptr(part->dkstats, i)->field;            \
 265         res;                                                            \
 266 })
 267
 268 static inline void part_stat_set_all(struct hd_struct *part, int value)
 269 {
 270         int i;
 271
 272         for_each_possible_cpu(i)
 273                 memset(per_cpu_ptr(part->dkstats, i), value,
 274                                 sizeof(struct disk_stats));
 275 }
 276
 277 #else /* !CONFIG_SMP */
 278 #define disk_stat_lock()        ({ rcu_read_lock(); 0; })
 279 #define disk_stat_unlock()      rcu_read_unlock()
 280
 281 #define disk_stat_add(cpu, gendiskp, field, addnd)                      \
 282         (gendiskp->dkstats.field += addnd)
 283 #define disk_stat_read(gendiskp, field) (gendiskp->dkstats.field)
 284
 285 static inline void disk_stat_set_all(struct gendisk *gendiskp, int value)
 286 {
 287         memset(&gendiskp->dkstats, value, sizeof (struct disk_stats));
 288 }
 289
 290 #define part_stat_add(cpu, part, field, addnd)                          \
 291         (part->dkstats.field += addnd)
 292
 293 #define all_stat_add(cpu, gendiskp, part, field, addnd, sector)         \
 294 ({                                                                      \
 295         if (part)                                                       \
 296                 part_stat_add(cpu, part, field, addnd);                 \
 297         disk_stat_add(cpu, gendiskp, field, addnd);                     \
 298 })
 299
 300 #define part_stat_read(part, field)     (part->dkstats.field)
 301
 302 static inline void part_stat_set_all(struct hd_struct *part, int value)
 303 {
 304         memset(&part->dkstats, value, sizeof(struct disk_stats));
 305 }
 306
 307 #endif /* CONFIG_SMP */
 308
 309 #define disk_stat_dec(cpu, gendiskp, field)                             \
 310         disk_stat_add(cpu, gendiskp, field, -1)
 311 #define disk_stat_inc(cpu, gendiskp, field)                             \
 312         disk_stat_add(cpu, gendiskp, field, 1)
 313 #define disk_stat_sub(cpu, gendiskp, field, subnd)                      \
 314         disk_stat_add(cpu, gendiskp, field, -subnd)
 315
 316 #define part_stat_dec(cpu, gendiskp, field)                             \
 317         part_stat_add(cpu, gendiskp, field, -1)
 318 #define part_stat_inc(cpu, gendiskp, field)                             \
 319         part_stat_add(cpu, gendiskp, field, 1)
 320 #define part_stat_sub(cpu, gendiskp, field, subnd)                      \
 321         part_stat_add(cpu, gendiskp, field, -subnd)
 322
 323 #define all_stat_dec(cpu, gendiskp, field, sector)                      \
 324         all_stat_add(cpu, gendiskp, field, -1, sector)
 325 #define all_stat_inc(cpu, gendiskp, part, field, sector)                \
 326         all_stat_add(cpu, gendiskp, part, field, 1, sector)
 327 #define all_stat_sub(cpu, gendiskp, part, field, subnd, sector)         \
 328         all_stat_add(cpu, gendiskp, part, field, -subnd, sector)
 329
 330 /* Inlines to alloc and free disk stats in struct gendisk */
 331 #ifdef  CONFIG_SMP
 332 static inline int init_disk_stats(struct gendisk *disk)
 333 {
 334         disk->dkstats = alloc_percpu(struct disk_stats);
 335         if (!disk->dkstats)
 336                 return 0;
 337         return 1;
 338 }
 339
 340 static inline void free_disk_stats(struct gendisk *disk)
 341 {
 342         free_percpu(disk->dkstats);
 343 }
 344
 345 static inline int init_part_stats(struct hd_struct *part)
 346 {
 347         part->dkstats = alloc_percpu(struct disk_stats);
 348         if (!part->dkstats)
 349                 return 0;
 350         return 1;
 351 }
 352
 353 static inline void free_part_stats(struct hd_struct *part)
 354 {
 355         free_percpu(part->dkstats);
 356 }
 357
 358 #else   /* CONFIG_SMP */
 359 static inline int init_disk_stats(struct gendisk *disk)
 360 {
 361         return 1;
 362 }
 363
 364 static inline void free_disk_stats(struct gendisk *disk)
 365 {
 366 }
 367
 368 static inline int init_part_stats(struct hd_struct *part)
 369 {
 370         return 1;
 371 }
 372
 373 static inline void free_part_stats(struct hd_struct *part)
 374 {
 375 }
 376 #endif  /* CONFIG_SMP */
 377
 378 /* drivers/block/ll_rw_blk.c */
 379 extern void disk_round_stats(int cpu, struct gendisk *disk);
 380 extern void part_round_stats(int cpu, struct hd_struct *part);
 381
 382 /* drivers/block/genhd.c */
 383 extern int get_blkdev_list(char *, int);
 384 extern void add_disk(struct gendisk *disk);
 385 extern void del_gendisk(struct gendisk *gp);
 386 extern void unlink_gendisk(struct gendisk *gp);
 387 extern struct gendisk *get_gendisk(dev_t dev, int *partno);
 388 extern struct block_device *bdget_disk(struct gendisk *disk, int partno);
 389
 390 extern void set_device_ro(struct block_device *bdev, int flag);
 391 extern void set_disk_ro(struct gendisk *disk, int flag);
 392
 393 /* drivers/char/random.c */
 394 extern void add_disk_randomness(struct gendisk *disk);
 395 extern void rand_initialize_disk(struct gendisk *disk);
 396
 397 static inline sector_t get_start_sect(struct block_device *bdev)
 398 {
 399         return bdev->bd_contains == bdev ? 0 : bdev->bd_part->start_sect;
 400 }
 401 static inline sector_t get_capacity(struct gendisk *disk)
 402 {
 403         return disk->capacity;
 404 }
 405 static inline void set_capacity(struct gendisk *disk, sector_t size)
 406 {
 407         disk->capacity = size;
 408 }
 409
 410 #ifdef CONFIG_SOLARIS_X86_PARTITION
 411
 412 #define SOLARIS_X86_NUMSLICE    16
 413 #define SOLARIS_X86_VTOC_SANE   (0x600DDEEEUL)
 414
 415 struct solaris_x86_slice {
 416         __le16 s_tag;           /* ID tag of partition */
 417         __le16 s_flag;          /* permission flags */
 418         __le32 s_start;         /* start sector no of partition */
 419         __le32 s_size;          /* # of blocks in partition */
 420 };
 421
 422 struct solaris_x86_vtoc {
 423         unsigned int v_bootinfo[3];     /* info needed by mboot (unsupported) */
 424         __le32 v_sanity;                /* to verify vtoc sanity */
 425         __le32 v_version;               /* layout version */
 426         char    v_volume[8];            /* volume name */
 427         __le16  v_sectorsz;             /* sector size in bytes */
 428         __le16  v_nparts;               /* number of partitions */
 429         unsigned int v_reserved[10];    /* free space */
 430         struct solaris_x86_slice
 431                 v_slice[SOLARIS_X86_NUMSLICE]; /* slice headers */
 432         unsigned int timestamp[SOLARIS_X86_NUMSLICE]; /* timestamp (unsupported) */
 433         char    v_asciilabel[128];      /* for compatibility */
 434 };
 435
 436 #endif /* CONFIG_SOLARIS_X86_PARTITION */
 437
 438 #ifdef CONFIG_BSD_DISKLABEL
 439 /*
 440  * BSD disklabel support by Yossi Gottlieb <yogo@math.tau.ac.il>
 441  * updated by Marc Espie <Marc.Espie@openbsd.org>
 442  */
 443
 444 /* check against BSD src/sys/sys/disklabel.h for consistency */
 445
 446 #define BSD_DISKMAGIC   (0x82564557UL)  /* The disk magic number */
 447 #define BSD_MAXPARTITIONS       16
 448 #define OPENBSD_MAXPARTITIONS   16
 449 #define BSD_FS_UNUSED           0       /* disklabel unused partition entry ID */
 450 struct bsd_disklabel {
 451         __le32  d_magic;                /* the magic number */
 452         __s16   d_type;                 /* drive type */
 453         __s16   d_subtype;              /* controller/d_type specific */
 454         char    d_typename[16];         /* type name, e.g. "eagle" */
 455         char    d_packname[16];                 /* pack identifier */
 456         __u32   d_secsize;              /* # of bytes per sector */
 457         __u32   d_nsectors;             /* # of data sectors per track */
 458         __u32   d_ntracks;              /* # of tracks per cylinder */
 459         __u32   d_ncylinders;           /* # of data cylinders per unit */
 460         __u32   d_secpercyl;            /* # of data sectors per cylinder */
 461         __u32   d_secperunit;           /* # of data sectors per unit */
 462         __u16   d_sparespertrack;       /* # of spare sectors per track */
 463         __u16   d_sparespercyl;         /* # of spare sectors per cylinder */
 464         __u32   d_acylinders;           /* # of alt. cylinders per unit */
 465         __u16   d_rpm;                  /* rotational speed */
 466         __u16   d_interleave;           /* hardware sector interleave */
 467         __u16   d_trackskew;            /* sector 0 skew, per track */
 468         __u16   d_cylskew;              /* sector 0 skew, per cylinder */
 469         __u32   d_headswitch;           /* head switch time, usec */
 470         __u32   d_trkseek;              /* track-to-track seek, usec */
 471         __u32   d_flags;                /* generic flags */
 472 #define NDDATA 5
 473         __u32   d_drivedata[NDDATA];    /* drive-type specific information */
 474 #define NSPARE 5
 475         __u32   d_spare[NSPARE];        /* reserved for future use */
 476         __le32  d_magic2;               /* the magic number (again) */
 477         __le16  d_checksum;             /* xor of data incl. partitions */
 478
 479                         /* filesystem and partition information: */
 480         __le16  d_npartitions;          /* number of partitions in following */
 481         __le32  d_bbsize;               /* size of boot area at sn0, bytes */
 482         __le32  d_sbsize;               /* max size of fs superblock, bytes */
 483         struct  bsd_partition {         /* the partition table */
 484                 __le32  p_size;         /* number of sectors in partition */
 485                 __le32  p_offset;       /* starting sector */
 486                 __le32  p_fsize;        /* filesystem basic fragment size */
 487                 __u8    p_fstype;       /* filesystem type, see below */
 488                 __u8    p_frag;         /* filesystem fragments per block */
 489                 __le16  p_cpg;          /* filesystem cylinders per group */
 490         } d_partitions[BSD_MAXPARTITIONS];      /* actually may be more */
 491 };
 492
 493 #endif  /* CONFIG_BSD_DISKLABEL */
 494
 495 #ifdef CONFIG_UNIXWARE_DISKLABEL
 496 /*
 497  * Unixware slices support by Andrzej Krzysztofowicz <ankry@mif.pg.gda.pl>
 498  * and Krzysztof G. Baranowski <kgb@knm.org.pl>
 499  */
 500
 501 #define UNIXWARE_DISKMAGIC     (0xCA5E600DUL)   /* The disk magic number */
 502 #define UNIXWARE_DISKMAGIC2    (0x600DDEEEUL)   /* The slice table magic nr */
 503 #define UNIXWARE_NUMSLICE      16
 504 #define UNIXWARE_FS_UNUSED     0                /* Unused slice entry ID */
 505
 506 struct unixware_slice {
 507         __le16   s_label;       /* label */
 508         __le16   s_flags;       /* permission flags */
 509         __le32   start_sect;    /* starting sector */
 510         __le32   nr_sects;      /* number of sectors in slice */
 511 };
 512
 513 struct unixware_disklabel {
 514         __le32   d_type;                /* drive type */
 515         __le32   d_magic;                /* the magic number */
 516         __le32   d_version;              /* version number */
 517         char    d_serial[12];           /* serial number of the device */
 518         __le32   d_ncylinders;           /* # of data cylinders per device */
 519         __le32   d_ntracks;              /* # of tracks per cylinder */
 520         __le32   d_nsectors;             /* # of data sectors per track */
 521         __le32   d_secsize;              /* # of bytes per sector */
 522         __le32   d_part_start;           /* # of first sector of this partition */
 523         __le32   d_unknown1[12];         /* ? */
 524         __le32  d_alt_tbl;              /* byte offset of alternate table */
 525         __le32  d_alt_len;              /* byte length of alternate table */
 526         __le32  d_phys_cyl;             /* # of physical cylinders per device */
 527         __le32  d_phys_trk;             /* # of physical tracks per cylinder */
 528         __le32  d_phys_sec;             /* # of physical sectors per track */
 529         __le32  d_phys_bytes;           /* # of physical bytes per sector */
 530         __le32  d_unknown2;             /* ? */
 531         __le32   d_unknown3;             /* ? */
 532         __le32  d_pad[8];               /* pad */
 533
 534         struct unixware_vtoc {
 535                 __le32  v_magic;                /* the magic number */
 536                 __le32  v_version;              /* version number */
 537                 char    v_name[8];              /* volume name */
 538                 __le16  v_nslices;              /* # of slices */
 539                 __le16  v_unknown1;             /* ? */
 540                 __le32  v_reserved[10];         /* reserved */
 541                 struct unixware_slice
 542                         v_slice[UNIXWARE_NUMSLICE];     /* slice headers */
 543         } vtoc;
 544
 545 };  /* 408 */
 546
 547 #endif /* CONFIG_UNIXWARE_DISKLABEL */
 548
 549 #ifdef CONFIG_MINIX_SUBPARTITION
 550 #   define MINIX_NR_SUBPARTITIONS  4
 551 #endif /* CONFIG_MINIX_SUBPARTITION */
 552
 553 #define ADDPART_FLAG_NONE       0
 554 #define ADDPART_FLAG_RAID       1
 555 #define ADDPART_FLAG_WHOLEDISK  2
 556
 557 extern dev_t blk_lookup_devt(const char *name, int partno);
 558 extern char *disk_name (struct gendisk *hd, int partno, char *buf);
 559
 560 extern int rescan_partitions(struct gendisk *disk, struct block_device *bdev);
 561 extern int __must_check add_partition(struct gendisk *, int, sector_t, sector_t, int);
 562 extern void delete_partition(struct gendisk *, int);
 563 extern void printk_all_partitions(void);
 564
 565 extern struct gendisk *alloc_disk_node(int minors, int node_id);
 566 extern struct gendisk *alloc_disk(int minors);
 567 extern struct kobject *get_disk(struct gendisk *disk);
 568 extern void put_disk(struct gendisk *disk);
 569 extern void blk_register_region(dev_t devt, unsigned long range,
 570                         struct module *module,
 571                         struct kobject *(*probe)(dev_t, int *, void *),
 572                         int (*lock)(dev_t, void *),
 573                         void *data);
 574 extern void blk_unregister_region(dev_t devt, unsigned long range);
 575
 576 #else /* CONFIG_BLOCK */
 577
 578 static inline void printk_all_partitions(void) { }
 579
 580 static inline dev_t blk_lookup_devt(const char *name, int partno)
 581 {
 582         dev_t devt = MKDEV(0, 0);
 583         return devt;
 584 }
 585
 586 #endif /* CONFIG_BLOCK */
 587
 588 #endif /* _LINUX_GENHD_H */