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 #include <linux/percpu-refcount.h>
  17 #include <linux/uuid.h>
  18
  19 #ifdef CONFIG_BLOCK
  20
  21 #define dev_to_disk(device)     container_of((device), struct gendisk, part0.__dev)
  22 #define dev_to_part(device)     container_of((device), struct hd_struct, __dev)
  23 #define disk_to_dev(disk)       (&(disk)->part0.__dev)
  24 #define part_to_dev(part)       (&((part)->__dev))
  25
  26 extern struct device_type part_type;
  27 extern struct kobject *block_depr;
  28 extern struct class block_class;
  29
  30 enum {
  31 /* These three have identical behaviour; use the second one if DOS FDISK gets
  32    confused about extended/logical partitions starting past cylinder 1023. */
  33         DOS_EXTENDED_PARTITION = 5,
  34         LINUX_EXTENDED_PARTITION = 0x85,
  35         WIN98_EXTENDED_PARTITION = 0x0f,
  36
  37         SUN_WHOLE_DISK = DOS_EXTENDED_PARTITION,
  38
  39         LINUX_SWAP_PARTITION = 0x82,
  40         LINUX_DATA_PARTITION = 0x83,
  41         LINUX_LVM_PARTITION = 0x8e,
  42         LINUX_RAID_PARTITION = 0xfd,    /* autodetect RAID partition */
  43
  44         SOLARIS_X86_PARTITION = LINUX_SWAP_PARTITION,
  45         NEW_SOLARIS_X86_PARTITION = 0xbf,
  46
  47         DM6_AUX1PARTITION = 0x51,       /* no DDO:  use xlated geom */
  48         DM6_AUX3PARTITION = 0x53,       /* no DDO:  use xlated geom */
  49         DM6_PARTITION = 0x54,           /* has DDO: use xlated geom & offset */
  50         EZD_PARTITION = 0x55,           /* EZ-DRIVE */
  51
  52         FREEBSD_PARTITION = 0xa5,       /* FreeBSD Partition ID */
  53         OPENBSD_PARTITION = 0xa6,       /* OpenBSD Partition ID */
  54         NETBSD_PARTITION = 0xa9,        /* NetBSD Partition ID */
  55         BSDI_PARTITION = 0xb7,          /* BSDI Partition ID */
  56         MINIX_PARTITION = 0x81,         /* Minix Partition ID */
  57         UNIXWARE_PARTITION = 0x63,      /* Same as GNU_HURD and SCO Unix */
  58 };
  59
  60 #define DISK_MAX_PARTS                  256
  61 #define DISK_NAME_LEN                   32
  62
  63 #include <linux/major.h>
  64 #include <linux/device.h>
  65 #include <linux/smp.h>
  66 #include <linux/string.h>
  67 #include <linux/fs.h>
  68 #include <linux/workqueue.h>
  69
  70 struct partition {
  71         unsigned char boot_ind;         /* 0x80 - active */
  72         unsigned char head;             /* starting head */
  73         unsigned char sector;           /* starting sector */
  74         unsigned char cyl;              /* starting cylinder */
  75         unsigned char sys_ind;          /* What partition type */
  76         unsigned char end_head;         /* end head */
  77         unsigned char end_sector;       /* end sector */
  78         unsigned char end_cyl;          /* end cylinder */
  79         __le32 start_sect;      /* starting sector counting from 0 */
  80         __le32 nr_sects;                /* nr of sectors in partition */
  81 } __attribute__((packed));
  82
  83 struct disk_stats {
  84         unsigned long sectors[2];       /* READs and WRITEs */
  85         unsigned long ios[2];
  86         unsigned long merges[2];
  87         unsigned long ticks[2];
  88         unsigned long io_ticks;
  89         unsigned long time_in_queue;
  90 };
  91
  92 #define PARTITION_META_INFO_VOLNAMELTH  64
  93 /*
  94  * Enough for the string representation of any kind of UUID plus NULL.
  95  * EFI UUID is 36 characters. MSDOS UUID is 11 characters.
  96  */
  97 #define PARTITION_META_INFO_UUIDLTH     (UUID_STRING_LEN + 1)
  98
  99 struct partition_meta_info {
 100         char uuid[PARTITION_META_INFO_UUIDLTH];
 101         u8 volname[PARTITION_META_INFO_VOLNAMELTH];
 102 };
 103
 104 struct hd_struct {
 105         sector_t start_sect;
 106         /*
 107          * nr_sects is protected by sequence counter. One might extend a
 108          * partition while IO is happening to it and update of nr_sects
 109          * can be non-atomic on 32bit machines with 64bit sector_t.
 110          */
 111         sector_t nr_sects;
 112         seqcount_t nr_sects_seq;
 113         sector_t alignment_offset;
 114         unsigned int discard_alignment;
 115         struct device __dev;
 116         struct kobject *holder_dir;
 117         int policy, partno;
 118         struct partition_meta_info *info;
 119 #ifdef CONFIG_FAIL_MAKE_REQUEST
 120         int make_it_fail;
 121 #endif
 122         unsigned long stamp;
 123         atomic_t in_flight[2];
 124 #ifdef  CONFIG_SMP
 125         struct disk_stats __percpu *dkstats;
 126 #else
 127         struct disk_stats dkstats;
 128 #endif
 129         struct percpu_ref ref;
 130         struct rcu_head rcu_head;
 131 };
 132
 133 #define GENHD_FL_REMOVABLE                      1
 134 /* 2 is unused */
 135 #define GENHD_FL_MEDIA_CHANGE_NOTIFY            4
 136 #define GENHD_FL_CD                             8
 137 #define GENHD_FL_UP                             16
 138 #define GENHD_FL_SUPPRESS_PARTITION_INFO        32
 139 #define GENHD_FL_EXT_DEVT                       64 /* allow extended devt */
 140 #define GENHD_FL_NATIVE_CAPACITY                128
 141 #define GENHD_FL_BLOCK_EVENTS_ON_EXCL_WRITE     256
 142 #define GENHD_FL_NO_PART_SCAN                   512
 143
 144 enum {
 145         DISK_EVENT_MEDIA_CHANGE                 = 1 << 0, /* media changed */
 146         DISK_EVENT_EJECT_REQUEST                = 1 << 1, /* eject requested */
 147 };
 148
 149 #define BLK_SCSI_MAX_CMDS       (256)
 150 #define BLK_SCSI_CMD_PER_LONG   (BLK_SCSI_MAX_CMDS / (sizeof(long) * 8))
 151
 152 struct blk_scsi_cmd_filter {
 153         unsigned long read_ok[BLK_SCSI_CMD_PER_LONG];
 154         unsigned long write_ok[BLK_SCSI_CMD_PER_LONG];
 155         struct kobject kobj;
 156 };
 157
 158 struct disk_part_tbl {
 159         struct rcu_head rcu_head;
 160         int len;
 161         struct hd_struct __rcu *last_lookup;
 162         struct hd_struct __rcu *part[];
 163 };
 164
 165 struct disk_events;
 166 struct badblocks;
 167
 168 #if defined(CONFIG_BLK_DEV_INTEGRITY)
 169
 170 struct blk_integrity {
 171         struct blk_integrity_profile    *profile;
 172         unsigned char                   flags;
 173         unsigned char                   tuple_size;
 174         unsigned char                   interval_exp;
 175         unsigned char                   tag_size;
 176 };
 177
 178 #endif  /* CONFIG_BLK_DEV_INTEGRITY */
 179
 180 struct gendisk {
 181         /* major, first_minor and minors are input parameters only,
 182          * don't use directly.  Use disk_devt() and disk_max_parts().
 183          */
 184         int major;                      /* major number of driver */
 185         int first_minor;
 186         int minors;                     /* maximum number of minors, =1 for
 187                                          * disks that can't be partitioned. */
 188
 189         char disk_name[DISK_NAME_LEN];  /* name of major driver */
 190         char *(*devnode)(struct gendisk *gd, umode_t *mode);
 191
 192         unsigned int events;            /* supported events */
 193         unsigned int async_events;      /* async events, subset of all */
 194
 195         /* Array of pointers to partitions indexed by partno.
 196          * Protected with matching bdev lock but stat and other
 197          * non-critical accesses use RCU.  Always access through
 198          * helpers.
 199          */
 200         struct disk_part_tbl __rcu *part_tbl;
 201         struct hd_struct part0;
 202
 203         const struct block_device_operations *fops;
 204         struct request_queue *queue;
 205         void *private_data;
 206
 207         int flags;
 208         struct device *driverfs_dev;  // FIXME: remove
 209         struct kobject *slave_dir;
 210
 211         struct timer_rand_state *random;
 212         atomic_t sync_io;               /* RAID */
 213         struct disk_events *ev;
 214 #ifdef  CONFIG_BLK_DEV_INTEGRITY
 215         struct kobject integrity_kobj;
 216 #endif  /* CONFIG_BLK_DEV_INTEGRITY */
 217         int node_id;
 218         struct badblocks *bb;
 219 };
 220
 221 static inline struct gendisk *part_to_disk(struct hd_struct *part)
 222 {
 223         if (likely(part)) {
 224                 if (part->partno)
 225                         return dev_to_disk(part_to_dev(part)->parent);
 226                 else
 227                         return dev_to_disk(part_to_dev(part));
 228         }
 229         return NULL;
 230 }
 231
 232 static inline int blk_part_pack_uuid(const u8 *uuid_str, u8 *to)
 233 {
 234         uuid_be_to_bin(uuid_str, (uuid_be *)to);
 235         return 0;
 236 }
 237
 238 static inline int disk_max_parts(struct gendisk *disk)
 239 {
 240         if (disk->flags & GENHD_FL_EXT_DEVT)
 241                 return DISK_MAX_PARTS;
 242         return disk->minors;
 243 }
 244
 245 static inline bool disk_part_scan_enabled(struct gendisk *disk)
 246 {
 247         return disk_max_parts(disk) > 1 &&
 248                 !(disk->flags & GENHD_FL_NO_PART_SCAN);
 249 }
 250
 251 static inline dev_t disk_devt(struct gendisk *disk)
 252 {
 253         return disk_to_dev(disk)->devt;
 254 }
 255
 256 static inline dev_t part_devt(struct hd_struct *part)
 257 {
 258         return part_to_dev(part)->devt;
 259 }
 260
 261 extern struct hd_struct *disk_get_part(struct gendisk *disk, int partno);
 262
 263 static inline void disk_put_part(struct hd_struct *part)
 264 {
 265         if (likely(part))
 266                 put_device(part_to_dev(part));
 267 }
 268
 269 /*
 270  * Smarter partition iterator without context limits.
 271  */
 272 #define DISK_PITER_REVERSE      (1 << 0) /* iterate in the reverse direction */
 273 #define DISK_PITER_INCL_EMPTY   (1 << 1) /* include 0-sized parts */
 274 #define DISK_PITER_INCL_PART0   (1 << 2) /* include partition 0 */
 275 #define DISK_PITER_INCL_EMPTY_PART0 (1 << 3) /* include empty partition 0 */
 276
 277 struct disk_part_iter {
 278         struct gendisk          *disk;
 279         struct hd_struct        *part;
 280         int                     idx;
 281         unsigned int            flags;
 282 };
 283
 284 extern void disk_part_iter_init(struct disk_part_iter *piter,
 285                                  struct gendisk *disk, unsigned int flags);
 286 extern struct hd_struct *disk_part_iter_next(struct disk_part_iter *piter);
 287 extern void disk_part_iter_exit(struct disk_part_iter *piter);
 288
 289 extern struct hd_struct *disk_map_sector_rcu(struct gendisk *disk,
 290                                              sector_t sector);
 291
 292 /*
 293  * Macros to operate on percpu disk statistics:
 294  *
 295  * {disk|part|all}_stat_{add|sub|inc|dec}() modify the stat counters
 296  * and should be called between disk_stat_lock() and
 297  * disk_stat_unlock().
 298  *
 299  * part_stat_read() can be called at any time.
 300  *
 301  * part_stat_{add|set_all}() and {init|free}_part_stats are for
 302  * internal use only.
 303  */
 304 #ifdef  CONFIG_SMP
 305 #define part_stat_lock()        ({ rcu_read_lock(); get_cpu(); })
 306 #define part_stat_unlock()      do { put_cpu(); rcu_read_unlock(); } while (0)
 307
 308 #define __part_stat_add(cpu, part, field, addnd)                        \
 309         (per_cpu_ptr((part)->dkstats, (cpu))->field += (addnd))
 310
 311 #define part_stat_read(part, field)                                     \
 312 ({                                                                      \
 313         typeof((part)->dkstats->field) res = 0;                         \
 314         unsigned int _cpu;                                              \
 315         for_each_possible_cpu(_cpu)                                     \
 316                 res += per_cpu_ptr((part)->dkstats, _cpu)->field;       \
 317         res;                                                            \
 318 })
 319
 320 static inline void part_stat_set_all(struct hd_struct *part, int value)
 321 {
 322         int i;
 323
 324         for_each_possible_cpu(i)
 325                 memset(per_cpu_ptr(part->dkstats, i), value,
 326                                 sizeof(struct disk_stats));
 327 }
 328
 329 static inline int init_part_stats(struct hd_struct *part)
 330 {
 331         part->dkstats = alloc_percpu(struct disk_stats);
 332         if (!part->dkstats)
 333                 return 0;
 334         return 1;
 335 }
 336
 337 static inline void free_part_stats(struct hd_struct *part)
 338 {
 339         free_percpu(part->dkstats);
 340 }
 341
 342 #else /* !CONFIG_SMP */
 343 #define part_stat_lock()        ({ rcu_read_lock(); 0; })
 344 #define part_stat_unlock()      rcu_read_unlock()
 345
 346 #define __part_stat_add(cpu, part, field, addnd)                                \
 347         ((part)->dkstats.field += addnd)
 348
 349 #define part_stat_read(part, field)     ((part)->dkstats.field)
 350
 351 static inline void part_stat_set_all(struct hd_struct *part, int value)
 352 {
 353         memset(&part->dkstats, value, sizeof(struct disk_stats));
 354 }
 355
 356 static inline int init_part_stats(struct hd_struct *part)
 357 {
 358         return 1;
 359 }
 360
 361 static inline void free_part_stats(struct hd_struct *part)
 362 {
 363 }
 364
 365 #endif /* CONFIG_SMP */
 366
 367 #define part_stat_add(cpu, part, field, addnd)  do {                    \
 368         __part_stat_add((cpu), (part), field, addnd);                   \
 369         if ((part)->partno)                                             \
 370                 __part_stat_add((cpu), &part_to_disk((part))->part0,    \
 371                                 field, addnd);                          \
 372 } while (0)
 373
 374 #define part_stat_dec(cpu, gendiskp, field)                             \
 375         part_stat_add(cpu, gendiskp, field, -1)
 376 #define part_stat_inc(cpu, gendiskp, field)                             \
 377         part_stat_add(cpu, gendiskp, field, 1)
 378 #define part_stat_sub(cpu, gendiskp, field, subnd)                      \
 379         part_stat_add(cpu, gendiskp, field, -subnd)
 380
 381 static inline void part_inc_in_flight(struct hd_struct *part, int rw)
 382 {
 383         atomic_inc(&part->in_flight[rw]);
 384         if (part->partno)
 385                 atomic_inc(&part_to_disk(part)->part0.in_flight[rw]);
 386 }
 387
 388 static inline void part_dec_in_flight(struct hd_struct *part, int rw)
 389 {
 390         atomic_dec(&part->in_flight[rw]);
 391         if (part->partno)
 392                 atomic_dec(&part_to_disk(part)->part0.in_flight[rw]);
 393 }
 394
 395 static inline int part_in_flight(struct hd_struct *part)
 396 {
 397         return atomic_read(&part->in_flight[0]) + atomic_read(&part->in_flight[1]);
 398 }
 399
 400 static inline struct partition_meta_info *alloc_part_info(struct gendisk *disk)
 401 {
 402         if (disk)
 403                 return kzalloc_node(sizeof(struct partition_meta_info),
 404                                     GFP_KERNEL, disk->node_id);
 405         return kzalloc(sizeof(struct partition_meta_info), GFP_KERNEL);
 406 }
 407
 408 static inline void free_part_info(struct hd_struct *part)
 409 {
 410         kfree(part->info);
 411 }
 412
 413 /* block/blk-core.c */
 414 extern void part_round_stats(int cpu, struct hd_struct *part);
 415
 416 /* block/genhd.c */
 417 extern void add_disk(struct gendisk *disk);
 418 extern void del_gendisk(struct gendisk *gp);
 419 extern struct gendisk *get_gendisk(dev_t dev, int *partno);
 420 extern struct block_device *bdget_disk(struct gendisk *disk, int partno);
 421
 422 extern void set_device_ro(struct block_device *bdev, int flag);
 423 extern void set_disk_ro(struct gendisk *disk, int flag);
 424
 425 static inline int get_disk_ro(struct gendisk *disk)
 426 {
 427         return disk->part0.policy;
 428 }
 429
 430 extern void disk_block_events(struct gendisk *disk);
 431 extern void disk_unblock_events(struct gendisk *disk);
 432 extern void disk_flush_events(struct gendisk *disk, unsigned int mask);
 433 extern unsigned int disk_clear_events(struct gendisk *disk, unsigned int mask);
 434
 435 /* drivers/char/random.c */
 436 extern void add_disk_randomness(struct gendisk *disk);
 437 extern void rand_initialize_disk(struct gendisk *disk);
 438
 439 static inline sector_t get_start_sect(struct block_device *bdev)
 440 {
 441         return bdev->bd_part->start_sect;
 442 }
 443 static inline sector_t get_capacity(struct gendisk *disk)
 444 {
 445         return disk->part0.nr_sects;
 446 }
 447 static inline void set_capacity(struct gendisk *disk, sector_t size)
 448 {
 449         disk->part0.nr_sects = size;
 450 }
 451
 452 #ifdef CONFIG_SOLARIS_X86_PARTITION
 453
 454 #define SOLARIS_X86_NUMSLICE    16
 455 #define SOLARIS_X86_VTOC_SANE   (0x600DDEEEUL)
 456
 457 struct solaris_x86_slice {
 458         __le16 s_tag;           /* ID tag of partition */
 459         __le16 s_flag;          /* permission flags */
 460         __le32 s_start;         /* start sector no of partition */
 461         __le32 s_size;          /* # of blocks in partition */
 462 };
 463
 464 struct solaris_x86_vtoc {
 465         unsigned int v_bootinfo[3];     /* info needed by mboot (unsupported) */
 466         __le32 v_sanity;                /* to verify vtoc sanity */
 467         __le32 v_version;               /* layout version */
 468         char    v_volume[8];            /* volume name */
 469         __le16  v_sectorsz;             /* sector size in bytes */
 470         __le16  v_nparts;               /* number of partitions */
 471         unsigned int v_reserved[10];    /* free space */
 472         struct solaris_x86_slice
 473                 v_slice[SOLARIS_X86_NUMSLICE]; /* slice headers */
 474         unsigned int timestamp[SOLARIS_X86_NUMSLICE]; /* timestamp (unsupported) */
 475         char    v_asciilabel[128];      /* for compatibility */
 476 };
 477
 478 #endif /* CONFIG_SOLARIS_X86_PARTITION */
 479
 480 #ifdef CONFIG_BSD_DISKLABEL
 481 /*
 482  * BSD disklabel support by Yossi Gottlieb <yogo@math.tau.ac.il>
 483  * updated by Marc Espie <Marc.Espie@openbsd.org>
 484  */
 485
 486 /* check against BSD src/sys/sys/disklabel.h for consistency */
 487
 488 #define BSD_DISKMAGIC   (0x82564557UL)  /* The disk magic number */
 489 #define BSD_MAXPARTITIONS       16
 490 #define OPENBSD_MAXPARTITIONS   16
 491 #define BSD_FS_UNUSED           0       /* disklabel unused partition entry ID */
 492 struct bsd_disklabel {
 493         __le32  d_magic;                /* the magic number */
 494         __s16   d_type;                 /* drive type */
 495         __s16   d_subtype;              /* controller/d_type specific */
 496         char    d_typename[16];         /* type name, e.g. "eagle" */
 497         char    d_packname[16];                 /* pack identifier */
 498         __u32   d_secsize;              /* # of bytes per sector */
 499         __u32   d_nsectors;             /* # of data sectors per track */
 500         __u32   d_ntracks;              /* # of tracks per cylinder */
 501         __u32   d_ncylinders;           /* # of data cylinders per unit */
 502         __u32   d_secpercyl;            /* # of data sectors per cylinder */
 503         __u32   d_secperunit;           /* # of data sectors per unit */
 504         __u16   d_sparespertrack;       /* # of spare sectors per track */
 505         __u16   d_sparespercyl;         /* # of spare sectors per cylinder */
 506         __u32   d_acylinders;           /* # of alt. cylinders per unit */
 507         __u16   d_rpm;                  /* rotational speed */
 508         __u16   d_interleave;           /* hardware sector interleave */
 509         __u16   d_trackskew;            /* sector 0 skew, per track */
 510         __u16   d_cylskew;              /* sector 0 skew, per cylinder */
 511         __u32   d_headswitch;           /* head switch time, usec */
 512         __u32   d_trkseek;              /* track-to-track seek, usec */
 513         __u32   d_flags;                /* generic flags */
 514 #define NDDATA 5
 515         __u32   d_drivedata[NDDATA];    /* drive-type specific information */
 516 #define NSPARE 5
 517         __u32   d_spare[NSPARE];        /* reserved for future use */
 518         __le32  d_magic2;               /* the magic number (again) */
 519         __le16  d_checksum;             /* xor of data incl. partitions */
 520
 521                         /* filesystem and partition information: */
 522         __le16  d_npartitions;          /* number of partitions in following */
 523         __le32  d_bbsize;               /* size of boot area at sn0, bytes */
 524         __le32  d_sbsize;               /* max size of fs superblock, bytes */
 525         struct  bsd_partition {         /* the partition table */
 526                 __le32  p_size;         /* number of sectors in partition */
 527                 __le32  p_offset;       /* starting sector */
 528                 __le32  p_fsize;        /* filesystem basic fragment size */
 529                 __u8    p_fstype;       /* filesystem type, see below */
 530                 __u8    p_frag;         /* filesystem fragments per block */
 531                 __le16  p_cpg;          /* filesystem cylinders per group */
 532         } d_partitions[BSD_MAXPARTITIONS];      /* actually may be more */
 533 };
 534
 535 #endif  /* CONFIG_BSD_DISKLABEL */
 536
 537 #ifdef CONFIG_UNIXWARE_DISKLABEL
 538 /*
 539  * Unixware slices support by Andrzej Krzysztofowicz <ankry@mif.pg.gda.pl>
 540  * and Krzysztof G. Baranowski <kgb@knm.org.pl>
 541  */
 542
 543 #define UNIXWARE_DISKMAGIC     (0xCA5E600DUL)   /* The disk magic number */
 544 #define UNIXWARE_DISKMAGIC2    (0x600DDEEEUL)   /* The slice table magic nr */
 545 #define UNIXWARE_NUMSLICE      16
 546 #define UNIXWARE_FS_UNUSED     0                /* Unused slice entry ID */
 547
 548 struct unixware_slice {
 549         __le16   s_label;       /* label */
 550         __le16   s_flags;       /* permission flags */
 551         __le32   start_sect;    /* starting sector */
 552         __le32   nr_sects;      /* number of sectors in slice */
 553 };
 554
 555 struct unixware_disklabel {
 556         __le32   d_type;                /* drive type */
 557         __le32   d_magic;                /* the magic number */
 558         __le32   d_version;              /* version number */
 559         char    d_serial[12];           /* serial number of the device */
 560         __le32   d_ncylinders;           /* # of data cylinders per device */
 561         __le32   d_ntracks;              /* # of tracks per cylinder */
 562         __le32   d_nsectors;             /* # of data sectors per track */
 563         __le32   d_secsize;              /* # of bytes per sector */
 564         __le32   d_part_start;           /* # of first sector of this partition */
 565         __le32   d_unknown1[12];         /* ? */
 566         __le32  d_alt_tbl;              /* byte offset of alternate table */
 567         __le32  d_alt_len;              /* byte length of alternate table */
 568         __le32  d_phys_cyl;             /* # of physical cylinders per device */
 569         __le32  d_phys_trk;             /* # of physical tracks per cylinder */
 570         __le32  d_phys_sec;             /* # of physical sectors per track */
 571         __le32  d_phys_bytes;           /* # of physical bytes per sector */
 572         __le32  d_unknown2;             /* ? */
 573         __le32   d_unknown3;             /* ? */
 574         __le32  d_pad[8];               /* pad */
 575
 576         struct unixware_vtoc {
 577                 __le32  v_magic;                /* the magic number */
 578                 __le32  v_version;              /* version number */
 579                 char    v_name[8];              /* volume name */
 580                 __le16  v_nslices;              /* # of slices */
 581                 __le16  v_unknown1;             /* ? */
 582                 __le32  v_reserved[10];         /* reserved */
 583                 struct unixware_slice
 584                         v_slice[UNIXWARE_NUMSLICE];     /* slice headers */
 585         } vtoc;
 586
 587 };  /* 408 */
 588
 589 #endif /* CONFIG_UNIXWARE_DISKLABEL */
 590
 591 #ifdef CONFIG_MINIX_SUBPARTITION
 592 #   define MINIX_NR_SUBPARTITIONS  4
 593 #endif /* CONFIG_MINIX_SUBPARTITION */
 594
 595 #define ADDPART_FLAG_NONE       0
 596 #define ADDPART_FLAG_RAID       1
 597 #define ADDPART_FLAG_WHOLEDISK  2
 598
 599 extern int blk_alloc_devt(struct hd_struct *part, dev_t *devt);
 600 extern void blk_free_devt(dev_t devt);
 601 extern dev_t blk_lookup_devt(const char *name, int partno);
 602 extern char *disk_name (struct gendisk *hd, int partno, char *buf);
 603
 604 extern int disk_expand_part_tbl(struct gendisk *disk, int target);
 605 extern int rescan_partitions(struct gendisk *disk, struct block_device *bdev);
 606 extern int invalidate_partitions(struct gendisk *disk, struct block_device *bdev);
 607 extern struct hd_struct * __must_check add_partition(struct gendisk *disk,
 608                                                      int partno, sector_t start,
 609                                                      sector_t len, int flags,
 610                                                      struct partition_meta_info
 611                                                        *info);
 612 extern void __delete_partition(struct percpu_ref *);
 613 extern void delete_partition(struct gendisk *, int);
 614 extern void printk_all_partitions(void);
 615
 616 extern struct gendisk *alloc_disk_node(int minors, int node_id);
 617 extern struct gendisk *alloc_disk(int minors);
 618 extern struct kobject *get_disk(struct gendisk *disk);
 619 extern void put_disk(struct gendisk *disk);
 620 extern void blk_register_region(dev_t devt, unsigned long range,
 621                         struct module *module,
 622                         struct kobject *(*probe)(dev_t, int *, void *),
 623                         int (*lock)(dev_t, void *),
 624                         void *data);
 625 extern void blk_unregister_region(dev_t devt, unsigned long range);
 626
 627 extern ssize_t part_size_show(struct device *dev,
 628                               struct device_attribute *attr, char *buf);
 629 extern ssize_t part_stat_show(struct device *dev,
 630                               struct device_attribute *attr, char *buf);
 631 extern ssize_t part_inflight_show(struct device *dev,
 632                               struct device_attribute *attr, char *buf);
 633 #ifdef CONFIG_FAIL_MAKE_REQUEST
 634 extern ssize_t part_fail_show(struct device *dev,
 635                               struct device_attribute *attr, char *buf);
 636 extern ssize_t part_fail_store(struct device *dev,
 637                                struct device_attribute *attr,
 638                                const char *buf, size_t count);
 639 #endif /* CONFIG_FAIL_MAKE_REQUEST */
 640
 641 static inline int hd_ref_init(struct hd_struct *part)
 642 {
 643         if (percpu_ref_init(&part->ref, __delete_partition, 0,
 644                                 GFP_KERNEL))
 645                 return -ENOMEM;
 646         return 0;
 647 }
 648
 649 static inline void hd_struct_get(struct hd_struct *part)
 650 {
 651         percpu_ref_get(&part->ref);
 652 }
 653
 654 static inline int hd_struct_try_get(struct hd_struct *part)
 655 {
 656         return percpu_ref_tryget_live(&part->ref);
 657 }
 658
 659 static inline void hd_struct_put(struct hd_struct *part)
 660 {
 661         percpu_ref_put(&part->ref);
 662 }
 663
 664 static inline void hd_struct_kill(struct hd_struct *part)
 665 {
 666         percpu_ref_kill(&part->ref);
 667 }
 668
 669 static inline void hd_free_part(struct hd_struct *part)
 670 {
 671         free_part_stats(part);
 672         free_part_info(part);
 673         percpu_ref_exit(&part->ref);
 674 }
 675
 676 /*
 677  * Any access of part->nr_sects which is not protected by partition
 678  * bd_mutex or gendisk bdev bd_mutex, should be done using this
 679  * accessor function.
 680  *
 681  * Code written along the lines of i_size_read() and i_size_write().
 682  * CONFIG_PREEMPT case optimizes the case of UP kernel with preemption
 683  * on.
 684  */
 685 static inline sector_t part_nr_sects_read(struct hd_struct *part)
 686 {
 687 #if BITS_PER_LONG==32 && defined(CONFIG_LBDAF) && defined(CONFIG_SMP)
 688         sector_t nr_sects;
 689         unsigned seq;
 690         do {
 691                 seq = read_seqcount_begin(&part->nr_sects_seq);
 692                 nr_sects = part->nr_sects;
 693         } while (read_seqcount_retry(&part->nr_sects_seq, seq));
 694         return nr_sects;
 695 #elif BITS_PER_LONG==32 && defined(CONFIG_LBDAF) && defined(CONFIG_PREEMPT)
 696         sector_t nr_sects;
 697
 698         preempt_disable();
 699         nr_sects = part->nr_sects;
 700         preempt_enable();
 701         return nr_sects;
 702 #else
 703         return part->nr_sects;
 704 #endif
 705 }
 706
 707 /*
 708  * Should be called with mutex lock held (typically bd_mutex) of partition
 709  * to provide mutual exlusion among writers otherwise seqcount might be
 710  * left in wrong state leaving the readers spinning infinitely.
 711  */
 712 static inline void part_nr_sects_write(struct hd_struct *part, sector_t size)
 713 {
 714 #if BITS_PER_LONG==32 && defined(CONFIG_LBDAF) && defined(CONFIG_SMP)
 715         write_seqcount_begin(&part->nr_sects_seq);
 716         part->nr_sects = size;
 717         write_seqcount_end(&part->nr_sects_seq);
 718 #elif BITS_PER_LONG==32 && defined(CONFIG_LBDAF) && defined(CONFIG_PREEMPT)
 719         preempt_disable();
 720         part->nr_sects = size;
 721         preempt_enable();
 722 #else
 723         part->nr_sects = size;
 724 #endif
 725 }
 726
 727 #if defined(CONFIG_BLK_DEV_INTEGRITY)
 728 extern void blk_integrity_add(struct gendisk *);
 729 extern void blk_integrity_del(struct gendisk *);
 730 extern void blk_integrity_revalidate(struct gendisk *);
 731 #else   /* CONFIG_BLK_DEV_INTEGRITY */
 732 static inline void blk_integrity_add(struct gendisk *disk) { }
 733 static inline void blk_integrity_del(struct gendisk *disk) { }
 734 static inline void blk_integrity_revalidate(struct gendisk *disk) { }
 735 #endif  /* CONFIG_BLK_DEV_INTEGRITY */
 736
 737 #else /* CONFIG_BLOCK */
 738
 739 static inline void printk_all_partitions(void) { }
 740
 741 static inline dev_t blk_lookup_devt(const char *name, int partno)
 742 {
 743         dev_t devt = MKDEV(0, 0);
 744         return devt;
 745 }
 746
 747 static inline int blk_part_pack_uuid(const u8 *uuid_str, u8 *to)
 748 {
 749         return -EINVAL;
 750 }
 751 #endif /* CONFIG_BLOCK */
 752
 753 #endif /* _LINUX_GENHD_H */