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 #include <linux/slab.h>
  16
  17 #ifdef CONFIG_BLOCK
  18
  19 #define kobj_to_dev(k)          container_of((k), struct device, kobj)
  20 #define dev_to_disk(device)     container_of((device), struct gendisk, part0.__dev)
  21 #define dev_to_part(device)     container_of((device), struct hd_struct, __dev)
  22 #define disk_to_dev(disk)       (&(disk)->part0.__dev)
  23 #define part_to_dev(part)       (&((part)->__dev))
  24
  25 extern struct device_type part_type;
  26 extern struct kobject *block_depr;
  27 extern struct class block_class;
  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 #define DISK_MAX_PARTS                  256
  60 #define DISK_NAME_LEN                   32
  61
  62 #include <linux/major.h>
  63 #include <linux/device.h>
  64 #include <linux/smp.h>
  65 #include <linux/string.h>
  66 #include <linux/fs.h>
  67 #include <linux/workqueue.h>
  68
  69 struct partition {
  70         unsigned char boot_ind;         /* 0x80 - active */
  71         unsigned char head;             /* starting head */
  72         unsigned char sector;           /* starting sector */
  73         unsigned char cyl;              /* starting cylinder */
  74         unsigned char sys_ind;          /* What partition type */
  75         unsigned char end_head;         /* end head */
  76         unsigned char end_sector;       /* end sector */
  77         unsigned char end_cyl;          /* end cylinder */
  78         __le32 start_sect;      /* starting sector counting from 0 */
  79         __le32 nr_sects;                /* nr of sectors in partition */
  80 } __attribute__((packed));
  81
  82 struct disk_stats {
  83         unsigned long sectors[2];       /* READs and WRITEs */
  84         unsigned long ios[2];
  85         unsigned long merges[2];
  86         unsigned long ticks[2];
  87         unsigned long io_ticks;
  88         unsigned long time_in_queue;
  89 };
  90
  91 #define PARTITION_META_INFO_VOLNAMELTH  64
  92 #define PARTITION_META_INFO_UUIDLTH     16
  93
  94 struct partition_meta_info {
  95         u8 uuid[PARTITION_META_INFO_UUIDLTH];   /* always big endian */
  96         u8 volname[PARTITION_META_INFO_VOLNAMELTH];
  97 };
  98
  99 struct hd_struct {
 100         sector_t start_sect;
 101         sector_t nr_sects;
 102         sector_t alignment_offset;
 103         unsigned int discard_alignment;
 104         struct device __dev;
 105         struct kobject *holder_dir;
 106         int policy, partno;
 107         struct partition_meta_info *info;
 108 #ifdef CONFIG_FAIL_MAKE_REQUEST
 109         int make_it_fail;
 110 #endif
 111         unsigned long stamp;
 112         atomic_t in_flight[2];
 113 #ifdef  CONFIG_SMP
 114         struct disk_stats __percpu *dkstats;
 115 #else
 116         struct disk_stats dkstats;
 117 #endif
 118         atomic_t ref;
 119         struct rcu_head rcu_head;
 120 };
 121
 122 #define GENHD_FL_REMOVABLE                      1
 123 /* 2 is unused */
 124 #define GENHD_FL_MEDIA_CHANGE_NOTIFY            4
 125 #define GENHD_FL_CD                             8
 126 #define GENHD_FL_UP                             16
 127 #define GENHD_FL_SUPPRESS_PARTITION_INFO        32
 128 #define GENHD_FL_EXT_DEVT                       64 /* allow extended devt */
 129 #define GENHD_FL_NATIVE_CAPACITY                128
 130 #define GENHD_FL_BLOCK_EVENTS_ON_EXCL_WRITE     256
 131
 132 enum {
 133         DISK_EVENT_MEDIA_CHANGE                 = 1 << 0, /* media changed */
 134         DISK_EVENT_EJECT_REQUEST                = 1 << 1, /* eject requested */
 135 };
 136
 137 #define BLK_SCSI_MAX_CMDS       (256)
 138 #define BLK_SCSI_CMD_PER_LONG   (BLK_SCSI_MAX_CMDS / (sizeof(long) * 8))
 139
 140 struct blk_scsi_cmd_filter {
 141         unsigned long read_ok[BLK_SCSI_CMD_PER_LONG];
 142         unsigned long write_ok[BLK_SCSI_CMD_PER_LONG];
 143         struct kobject kobj;
 144 };
 145
 146 struct disk_part_tbl {
 147         struct rcu_head rcu_head;
 148         int len;
 149         struct hd_struct __rcu *last_lookup;
 150         struct hd_struct __rcu *part[];
 151 };
 152
 153 struct disk_events;
 154
 155 struct gendisk {
 156         /* major, first_minor and minors are input parameters only,
 157          * don't use directly.  Use disk_devt() and disk_max_parts().
 158          */
 159         int major;                      /* major number of driver */
 160         int first_minor;
 161         int minors;                     /* maximum number of minors, =1 for
 162                                          * disks that can't be partitioned. */
 163
 164         char disk_name[DISK_NAME_LEN];  /* name of major driver */
 165         char *(*devnode)(struct gendisk *gd, mode_t *mode);
 166
 167         unsigned int events;            /* supported events */
 168         unsigned int async_events;      /* async events, subset of all */
 169
 170         /* Array of pointers to partitions indexed by partno.
 171          * Protected with matching bdev lock but stat and other
 172          * non-critical accesses use RCU.  Always access through
 173          * helpers.
 174          */
 175         struct disk_part_tbl __rcu *part_tbl;
 176         struct hd_struct part0;
 177
 178         const struct block_device_operations *fops;
 179         struct request_queue *queue;
 180         void *private_data;
 181
 182         int flags;
 183         struct device *driverfs_dev;  // FIXME: remove
 184         struct kobject *slave_dir;
 185
 186         struct timer_rand_state *random;
 187         atomic_t sync_io;               /* RAID */
 188         struct disk_events *ev;
 189 #ifdef  CONFIG_BLK_DEV_INTEGRITY
 190         struct blk_integrity *integrity;
 191 #endif
 192         int node_id;
 193 };
 194
 195 static inline struct gendisk *part_to_disk(struct hd_struct *part)
 196 {
 197         if (likely(part)) {
 198                 if (part->partno)
 199                         return dev_to_disk(part_to_dev(part)->parent);
 200                 else
 201                         return dev_to_disk(part_to_dev(part));
 202         }
 203         return NULL;
 204 }
 205
 206 static inline void part_pack_uuid(const u8 *uuid_str, u8 *to)
 207 {
 208         int i;
 209         for (i = 0; i < 16; ++i) {
 210                 *to++ = (hex_to_bin(*uuid_str) << 4) |
 211                         (hex_to_bin(*(uuid_str + 1)));
 212                 uuid_str += 2;
 213                 switch (i) {
 214                 case 3:
 215                 case 5:
 216                 case 7:
 217                 case 9:
 218                         uuid_str++;
 219                         continue;
 220                 }
 221         }
 222 }
 223
 224 static inline char *part_unpack_uuid(const u8 *uuid, char *out)
 225 {
 226         sprintf(out, "%pU", uuid);
 227         return out;
 228 }
 229
 230 static inline int disk_max_parts(struct gendisk *disk)
 231 {
 232         if (disk->flags & GENHD_FL_EXT_DEVT)
 233                 return DISK_MAX_PARTS;
 234         return disk->minors;
 235 }
 236
 237 static inline bool disk_partitionable(struct gendisk *disk)
 238 {
 239         return disk_max_parts(disk) > 1;
 240 }
 241
 242 static inline dev_t disk_devt(struct gendisk *disk)
 243 {
 244         return disk_to_dev(disk)->devt;
 245 }
 246
 247 static inline dev_t part_devt(struct hd_struct *part)
 248 {
 249         return part_to_dev(part)->devt;
 250 }
 251
 252 extern struct hd_struct *disk_get_part(struct gendisk *disk, int partno);
 253
 254 static inline void disk_put_part(struct hd_struct *part)
 255 {
 256         if (likely(part))
 257                 put_device(part_to_dev(part));
 258 }
 259
 260 /*
 261  * Smarter partition iterator without context limits.
 262  */
 263 #define DISK_PITER_REVERSE      (1 << 0) /* iterate in the reverse direction */
 264 #define DISK_PITER_INCL_EMPTY   (1 << 1) /* include 0-sized parts */
 265 #define DISK_PITER_INCL_PART0   (1 << 2) /* include partition 0 */
 266 #define DISK_PITER_INCL_EMPTY_PART0 (1 << 3) /* include empty partition 0 */
 267
 268 struct disk_part_iter {
 269         struct gendisk          *disk;
 270         struct hd_struct        *part;
 271         int                     idx;
 272         unsigned int            flags;
 273 };
 274
 275 extern void disk_part_iter_init(struct disk_part_iter *piter,
 276                                  struct gendisk *disk, unsigned int flags);
 277 extern struct hd_struct *disk_part_iter_next(struct disk_part_iter *piter);
 278 extern void disk_part_iter_exit(struct disk_part_iter *piter);
 279
 280 extern struct hd_struct *disk_map_sector_rcu(struct gendisk *disk,
 281                                              sector_t sector);
 282
 283 /*
 284  * Macros to operate on percpu disk statistics:
 285  *
 286  * {disk|part|all}_stat_{add|sub|inc|dec}() modify the stat counters
 287  * and should be called between disk_stat_lock() and
 288  * disk_stat_unlock().
 289  *
 290  * part_stat_read() can be called at any time.
 291  *
 292  * part_stat_{add|set_all}() and {init|free}_part_stats are for
 293  * internal use only.
 294  */
 295 #ifdef  CONFIG_SMP
 296 #define part_stat_lock()        ({ rcu_read_lock(); get_cpu(); })
 297 #define part_stat_unlock()      do { put_cpu(); rcu_read_unlock(); } while (0)
 298
 299 #define __part_stat_add(cpu, part, field, addnd)                        \
 300         (per_cpu_ptr((part)->dkstats, (cpu))->field += (addnd))
 301
 302 #define part_stat_read(part, field)                                     \
 303 ({                                                                      \
 304         typeof((part)->dkstats->field) res = 0;                         \
 305         unsigned int _cpu;                                              \
 306         for_each_possible_cpu(_cpu)                                     \
 307                 res += per_cpu_ptr((part)->dkstats, _cpu)->field;       \
 308         res;                                                            \
 309 })
 310
 311 static inline void part_stat_set_all(struct hd_struct *part, int value)
 312 {
 313         int i;
 314
 315         for_each_possible_cpu(i)
 316                 memset(per_cpu_ptr(part->dkstats, i), value,
 317                                 sizeof(struct disk_stats));
 318 }
 319
 320 static inline int init_part_stats(struct hd_struct *part)
 321 {
 322         part->dkstats = alloc_percpu(struct disk_stats);
 323         if (!part->dkstats)
 324                 return 0;
 325         return 1;
 326 }
 327
 328 static inline void free_part_stats(struct hd_struct *part)
 329 {
 330         free_percpu(part->dkstats);
 331 }
 332
 333 #else /* !CONFIG_SMP */
 334 #define part_stat_lock()        ({ rcu_read_lock(); 0; })
 335 #define part_stat_unlock()      rcu_read_unlock()
 336
 337 #define __part_stat_add(cpu, part, field, addnd)                                \
 338         ((part)->dkstats.field += addnd)
 339
 340 #define part_stat_read(part, field)     ((part)->dkstats.field)
 341
 342 static inline void part_stat_set_all(struct hd_struct *part, int value)
 343 {
 344         memset(&part->dkstats, value, sizeof(struct disk_stats));
 345 }
 346
 347 static inline int init_part_stats(struct hd_struct *part)
 348 {
 349         return 1;
 350 }
 351
 352 static inline void free_part_stats(struct hd_struct *part)
 353 {
 354 }
 355
 356 #endif /* CONFIG_SMP */
 357
 358 #define part_stat_add(cpu, part, field, addnd)  do {                    \
 359         __part_stat_add((cpu), (part), field, addnd);                   \
 360         if ((part)->partno)                                             \
 361                 __part_stat_add((cpu), &part_to_disk((part))->part0,    \
 362                                 field, addnd);                          \
 363 } while (0)
 364
 365 #define part_stat_dec(cpu, gendiskp, field)                             \
 366         part_stat_add(cpu, gendiskp, field, -1)
 367 #define part_stat_inc(cpu, gendiskp, field)                             \
 368         part_stat_add(cpu, gendiskp, field, 1)
 369 #define part_stat_sub(cpu, gendiskp, field, subnd)                      \
 370         part_stat_add(cpu, gendiskp, field, -subnd)
 371
 372 static inline void part_inc_in_flight(struct hd_struct *part, int rw)
 373 {
 374         atomic_inc(&part->in_flight[rw]);
 375         if (part->partno)
 376                 atomic_inc(&part_to_disk(part)->part0.in_flight[rw]);
 377 }
 378
 379 static inline void part_dec_in_flight(struct hd_struct *part, int rw)
 380 {
 381         atomic_dec(&part->in_flight[rw]);
 382         if (part->partno)
 383                 atomic_dec(&part_to_disk(part)->part0.in_flight[rw]);
 384 }
 385
 386 static inline int part_in_flight(struct hd_struct *part)
 387 {
 388         return atomic_read(&part->in_flight[0]) + atomic_read(&part->in_flight[1]);
 389 }
 390
 391 static inline struct partition_meta_info *alloc_part_info(struct gendisk *disk)
 392 {
 393         if (disk)
 394                 return kzalloc_node(sizeof(struct partition_meta_info),
 395                                     GFP_KERNEL, disk->node_id);
 396         return kzalloc(sizeof(struct partition_meta_info), GFP_KERNEL);
 397 }
 398
 399 static inline void free_part_info(struct hd_struct *part)
 400 {
 401         kfree(part->info);
 402 }
 403
 404 /* block/blk-core.c */
 405 extern void part_round_stats(int cpu, struct hd_struct *part);
 406
 407 /* block/genhd.c */
 408 extern void add_disk(struct gendisk *disk);
 409 extern void del_gendisk(struct gendisk *gp);
 410 extern struct gendisk *get_gendisk(dev_t dev, int *partno);
 411 extern struct block_device *bdget_disk(struct gendisk *disk, int partno);
 412
 413 extern void set_device_ro(struct block_device *bdev, int flag);
 414 extern void set_disk_ro(struct gendisk *disk, int flag);
 415
 416 static inline int get_disk_ro(struct gendisk *disk)
 417 {
 418         return disk->part0.policy;
 419 }
 420
 421 extern void disk_block_events(struct gendisk *disk);
 422 extern void disk_unblock_events(struct gendisk *disk);
 423 extern void disk_flush_events(struct gendisk *disk, unsigned int mask);
 424 extern unsigned int disk_clear_events(struct gendisk *disk, unsigned int mask);
 425
 426 /* drivers/char/random.c */
 427 extern void add_disk_randomness(struct gendisk *disk);
 428 extern void rand_initialize_disk(struct gendisk *disk);
 429
 430 static inline sector_t get_start_sect(struct block_device *bdev)
 431 {
 432         return bdev->bd_part->start_sect;
 433 }
 434 static inline sector_t get_capacity(struct gendisk *disk)
 435 {
 436         return disk->part0.nr_sects;
 437 }
 438 static inline void set_capacity(struct gendisk *disk, sector_t size)
 439 {
 440         disk->part0.nr_sects = size;
 441 }
 442
 443 #ifdef CONFIG_SOLARIS_X86_PARTITION
 444
 445 #define SOLARIS_X86_NUMSLICE    16
 446 #define SOLARIS_X86_VTOC_SANE   (0x600DDEEEUL)
 447
 448 struct solaris_x86_slice {
 449         __le16 s_tag;           /* ID tag of partition */
 450         __le16 s_flag;          /* permission flags */
 451         __le32 s_start;         /* start sector no of partition */
 452         __le32 s_size;          /* # of blocks in partition */
 453 };
 454
 455 struct solaris_x86_vtoc {
 456         unsigned int v_bootinfo[3];     /* info needed by mboot (unsupported) */
 457         __le32 v_sanity;                /* to verify vtoc sanity */
 458         __le32 v_version;               /* layout version */
 459         char    v_volume[8];            /* volume name */
 460         __le16  v_sectorsz;             /* sector size in bytes */
 461         __le16  v_nparts;               /* number of partitions */
 462         unsigned int v_reserved[10];    /* free space */
 463         struct solaris_x86_slice
 464                 v_slice[SOLARIS_X86_NUMSLICE]; /* slice headers */
 465         unsigned int timestamp[SOLARIS_X86_NUMSLICE]; /* timestamp (unsupported) */
 466         char    v_asciilabel[128];      /* for compatibility */
 467 };
 468
 469 #endif /* CONFIG_SOLARIS_X86_PARTITION */
 470
 471 #ifdef CONFIG_BSD_DISKLABEL
 472 /*
 473  * BSD disklabel support by Yossi Gottlieb <yogo@math.tau.ac.il>
 474  * updated by Marc Espie <Marc.Espie@openbsd.org>
 475  */
 476
 477 /* check against BSD src/sys/sys/disklabel.h for consistency */
 478
 479 #define BSD_DISKMAGIC   (0x82564557UL)  /* The disk magic number */
 480 #define BSD_MAXPARTITIONS       16
 481 #define OPENBSD_MAXPARTITIONS   16
 482 #define BSD_FS_UNUSED           0       /* disklabel unused partition entry ID */
 483 struct bsd_disklabel {
 484         __le32  d_magic;                /* the magic number */
 485         __s16   d_type;                 /* drive type */
 486         __s16   d_subtype;              /* controller/d_type specific */
 487         char    d_typename[16];         /* type name, e.g. "eagle" */
 488         char    d_packname[16];                 /* pack identifier */
 489         __u32   d_secsize;              /* # of bytes per sector */
 490         __u32   d_nsectors;             /* # of data sectors per track */
 491         __u32   d_ntracks;              /* # of tracks per cylinder */
 492         __u32   d_ncylinders;           /* # of data cylinders per unit */
 493         __u32   d_secpercyl;            /* # of data sectors per cylinder */
 494         __u32   d_secperunit;           /* # of data sectors per unit */
 495         __u16   d_sparespertrack;       /* # of spare sectors per track */
 496         __u16   d_sparespercyl;         /* # of spare sectors per cylinder */
 497         __u32   d_acylinders;           /* # of alt. cylinders per unit */
 498         __u16   d_rpm;                  /* rotational speed */
 499         __u16   d_interleave;           /* hardware sector interleave */
 500         __u16   d_trackskew;            /* sector 0 skew, per track */
 501         __u16   d_cylskew;              /* sector 0 skew, per cylinder */
 502         __u32   d_headswitch;           /* head switch time, usec */
 503         __u32   d_trkseek;              /* track-to-track seek, usec */
 504         __u32   d_flags;                /* generic flags */
 505 #define NDDATA 5
 506         __u32   d_drivedata[NDDATA];    /* drive-type specific information */
 507 #define NSPARE 5
 508         __u32   d_spare[NSPARE];        /* reserved for future use */
 509         __le32  d_magic2;               /* the magic number (again) */
 510         __le16  d_checksum;             /* xor of data incl. partitions */
 511
 512                         /* filesystem and partition information: */
 513         __le16  d_npartitions;          /* number of partitions in following */
 514         __le32  d_bbsize;               /* size of boot area at sn0, bytes */
 515         __le32  d_sbsize;               /* max size of fs superblock, bytes */
 516         struct  bsd_partition {         /* the partition table */
 517                 __le32  p_size;         /* number of sectors in partition */
 518                 __le32  p_offset;       /* starting sector */
 519                 __le32  p_fsize;        /* filesystem basic fragment size */
 520                 __u8    p_fstype;       /* filesystem type, see below */
 521                 __u8    p_frag;         /* filesystem fragments per block */
 522                 __le16  p_cpg;          /* filesystem cylinders per group */
 523         } d_partitions[BSD_MAXPARTITIONS];      /* actually may be more */
 524 };
 525
 526 #endif  /* CONFIG_BSD_DISKLABEL */
 527
 528 #ifdef CONFIG_UNIXWARE_DISKLABEL
 529 /*
 530  * Unixware slices support by Andrzej Krzysztofowicz <ankry@mif.pg.gda.pl>
 531  * and Krzysztof G. Baranowski <kgb@knm.org.pl>
 532  */
 533
 534 #define UNIXWARE_DISKMAGIC     (0xCA5E600DUL)   /* The disk magic number */
 535 #define UNIXWARE_DISKMAGIC2    (0x600DDEEEUL)   /* The slice table magic nr */
 536 #define UNIXWARE_NUMSLICE      16
 537 #define UNIXWARE_FS_UNUSED     0                /* Unused slice entry ID */
 538
 539 struct unixware_slice {
 540         __le16   s_label;       /* label */
 541         __le16   s_flags;       /* permission flags */
 542         __le32   start_sect;    /* starting sector */
 543         __le32   nr_sects;      /* number of sectors in slice */
 544 };
 545
 546 struct unixware_disklabel {
 547         __le32   d_type;                /* drive type */
 548         __le32   d_magic;                /* the magic number */
 549         __le32   d_version;              /* version number */
 550         char    d_serial[12];           /* serial number of the device */
 551         __le32   d_ncylinders;           /* # of data cylinders per device */
 552         __le32   d_ntracks;              /* # of tracks per cylinder */
 553         __le32   d_nsectors;             /* # of data sectors per track */
 554         __le32   d_secsize;              /* # of bytes per sector */
 555         __le32   d_part_start;           /* # of first sector of this partition */
 556         __le32   d_unknown1[12];         /* ? */
 557         __le32  d_alt_tbl;              /* byte offset of alternate table */
 558         __le32  d_alt_len;              /* byte length of alternate table */
 559         __le32  d_phys_cyl;             /* # of physical cylinders per device */
 560         __le32  d_phys_trk;             /* # of physical tracks per cylinder */
 561         __le32  d_phys_sec;             /* # of physical sectors per track */
 562         __le32  d_phys_bytes;           /* # of physical bytes per sector */
 563         __le32  d_unknown2;             /* ? */
 564         __le32   d_unknown3;             /* ? */
 565         __le32  d_pad[8];               /* pad */
 566
 567         struct unixware_vtoc {
 568                 __le32  v_magic;                /* the magic number */
 569                 __le32  v_version;              /* version number */
 570                 char    v_name[8];              /* volume name */
 571                 __le16  v_nslices;              /* # of slices */
 572                 __le16  v_unknown1;             /* ? */
 573                 __le32  v_reserved[10];         /* reserved */
 574                 struct unixware_slice
 575                         v_slice[UNIXWARE_NUMSLICE];     /* slice headers */
 576         } vtoc;
 577
 578 };  /* 408 */
 579
 580 #endif /* CONFIG_UNIXWARE_DISKLABEL */
 581
 582 #ifdef CONFIG_MINIX_SUBPARTITION
 583 #   define MINIX_NR_SUBPARTITIONS  4
 584 #endif /* CONFIG_MINIX_SUBPARTITION */
 585
 586 #define ADDPART_FLAG_NONE       0
 587 #define ADDPART_FLAG_RAID       1
 588 #define ADDPART_FLAG_WHOLEDISK  2
 589
 590 extern int blk_alloc_devt(struct hd_struct *part, dev_t *devt);
 591 extern void blk_free_devt(dev_t devt);
 592 extern dev_t blk_lookup_devt(const char *name, int partno);
 593 extern char *disk_name (struct gendisk *hd, int partno, char *buf);
 594
 595 extern int disk_expand_part_tbl(struct gendisk *disk, int target);
 596 extern int rescan_partitions(struct gendisk *disk, struct block_device *bdev);
 597 extern struct hd_struct * __must_check add_partition(struct gendisk *disk,
 598                                                      int partno, sector_t start,
 599                                                      sector_t len, int flags,
 600                                                      struct partition_meta_info
 601                                                        *info);
 602 extern void __delete_partition(struct hd_struct *);
 603 extern void delete_partition(struct gendisk *, int);
 604 extern void printk_all_partitions(void);
 605
 606 extern struct gendisk *alloc_disk_node(int minors, int node_id);
 607 extern struct gendisk *alloc_disk(int minors);
 608 extern struct kobject *get_disk(struct gendisk *disk);
 609 extern void put_disk(struct gendisk *disk);
 610 extern void blk_register_region(dev_t devt, unsigned long range,
 611                         struct module *module,
 612                         struct kobject *(*probe)(dev_t, int *, void *),
 613                         int (*lock)(dev_t, void *),
 614                         void *data);
 615 extern void blk_unregister_region(dev_t devt, unsigned long range);
 616
 617 extern ssize_t part_size_show(struct device *dev,
 618                               struct device_attribute *attr, char *buf);
 619 extern ssize_t part_stat_show(struct device *dev,
 620                               struct device_attribute *attr, char *buf);
 621 extern ssize_t part_inflight_show(struct device *dev,
 622                               struct device_attribute *attr, char *buf);
 623 #ifdef CONFIG_FAIL_MAKE_REQUEST
 624 extern ssize_t part_fail_show(struct device *dev,
 625                               struct device_attribute *attr, char *buf);
 626 extern ssize_t part_fail_store(struct device *dev,
 627                                struct device_attribute *attr,
 628                                const char *buf, size_t count);
 629 #endif /* CONFIG_FAIL_MAKE_REQUEST */
 630
 631 static inline void hd_ref_init(struct hd_struct *part)
 632 {
 633         atomic_set(&part->ref, 1);
 634         smp_mb();
 635 }
 636
 637 static inline void hd_struct_get(struct hd_struct *part)
 638 {
 639         atomic_inc(&part->ref);
 640         smp_mb__after_atomic_inc();
 641 }
 642
 643 static inline int hd_struct_try_get(struct hd_struct *part)
 644 {
 645         return atomic_inc_not_zero(&part->ref);
 646 }
 647
 648 static inline void hd_struct_put(struct hd_struct *part)
 649 {
 650         if (atomic_dec_and_test(&part->ref))
 651                 __delete_partition(part);
 652 }
 653
 654 #else /* CONFIG_BLOCK */
 655
 656 static inline void printk_all_partitions(void) { }
 657
 658 static inline dev_t blk_lookup_devt(const char *name, int partno)
 659 {
 660         dev_t devt = MKDEV(0, 0);
 661         return devt;
 662 }
 663
 664 #endif /* CONFIG_BLOCK */
 665
 666 #endif /* _LINUX_GENHD_H */