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
  18 #ifdef CONFIG_BLOCK
  19
  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 /*
  93  * Enough for the string representation of any kind of UUID plus NULL.
  94  * EFI UUID is 36 characters. MSDOS UUID is 11 characters.
  95  */
  96 #define PARTITION_META_INFO_UUIDLTH     37
  97
  98 struct partition_meta_info {
  99         char uuid[PARTITION_META_INFO_UUIDLTH];
 100         u8 volname[PARTITION_META_INFO_VOLNAMELTH];
 101 };
 102
 103 struct hd_struct {
 104         sector_t start_sect;
 105         /*
 106          * nr_sects is protected by sequence counter. One might extend a
 107          * partition while IO is happening to it and update of nr_sects
 108          * can be non-atomic on 32bit machines with 64bit sector_t.
 109          */
 110         sector_t nr_sects;
 111         seqcount_t nr_sects_seq;
 112         sector_t alignment_offset;
 113         unsigned int discard_alignment;
 114         struct device __dev;
 115         struct kobject *holder_dir;
 116         int policy, partno;
 117         struct partition_meta_info *info;
 118 #ifdef CONFIG_FAIL_MAKE_REQUEST
 119         int make_it_fail;
 120 #endif
 121         unsigned long stamp;
 122         atomic_t in_flight[2];
 123 #ifdef  CONFIG_SMP
 124         struct disk_stats __percpu *dkstats;
 125 #else
 126         struct disk_stats dkstats;
 127 #endif
 128         struct percpu_ref ref;
 129         struct rcu_head rcu_head;
 130 };
 131
 132 #define GENHD_FL_REMOVABLE                      1
 133 /* 2 is unused */
 134 #define GENHD_FL_MEDIA_CHANGE_NOTIFY            4
 135 #define GENHD_FL_CD                             8
 136 #define GENHD_FL_UP                             16
 137 #define GENHD_FL_SUPPRESS_PARTITION_INFO        32
 138 #define GENHD_FL_EXT_DEVT                       64 /* allow extended devt */
 139 #define GENHD_FL_NATIVE_CAPACITY                128
 140 #define GENHD_FL_BLOCK_EVENTS_ON_EXCL_WRITE     256
 141 #define GENHD_FL_NO_PART_SCAN                   512
 142
 143 enum {
 144         DISK_EVENT_MEDIA_CHANGE                 = 1 << 0, /* media changed */
 145         DISK_EVENT_EJECT_REQUEST                = 1 << 1, /* eject requested */
 146 };
 147
 148 #define BLK_SCSI_MAX_CMDS       (256)
 149 #define BLK_SCSI_CMD_PER_LONG   (BLK_SCSI_MAX_CMDS / (sizeof(long) * 8))
 150
 151 struct blk_scsi_cmd_filter {
 152         unsigned long read_ok[BLK_SCSI_CMD_PER_LONG];
 153         unsigned long write_ok[BLK_SCSI_CMD_PER_LONG];
 154         struct kobject kobj;
 155 };
 156
 157 struct disk_part_tbl {
 158         struct rcu_head rcu_head;
 159         int len;
 160         struct hd_struct __rcu *last_lookup;
 161         struct hd_struct __rcu *part[];
 162 };
 163
 164 struct disk_events;
 165
 166 #if defined(CONFIG_BLK_DEV_INTEGRITY)
 167
 168 struct blk_integrity {
 169         struct blk_integrity_profile    *profile;
 170         unsigned char                   flags;
 171         unsigned char                   tuple_size;
 172         unsigned char                   interval_exp;
 173         unsigned char                   tag_size;
 174 };
 175
 176 #endif  /* CONFIG_BLK_DEV_INTEGRITY */
 177
 178 struct gendisk {
 179         /* major, first_minor and minors are input parameters only,
 180          * don't use directly.  Use disk_devt() and disk_max_parts().
 181          */
 182         int major;                      /* major number of driver */
 183         int first_minor;
 184         int minors;                     /* maximum number of minors, =1 for
 185                                          * disks that can't be partitioned. */
 186
 187         char disk_name[DISK_NAME_LEN];  /* name of major driver */
 188         char *(*devnode)(struct gendisk *gd, umode_t *mode);
 189
 190         unsigned int events;            /* supported events */
 191         unsigned int async_events;      /* async events, subset of all */
 192
 193         /* Array of pointers to partitions indexed by partno.
 194          * Protected with matching bdev lock but stat and other
 195          * non-critical accesses use RCU.  Always access through
 196          * helpers.
 197          */
 198         struct disk_part_tbl __rcu *part_tbl;
 199         struct hd_struct part0;
 200
 201         const struct block_device_operations *fops;
 202         struct request_queue *queue;
 203         void *private_data;
 204
 205         int flags;
 206         struct device *driverfs_dev;  // FIXME: remove
 207         struct kobject *slave_dir;
 208
 209         struct timer_rand_state *random;
 210         atomic_t sync_io;               /* RAID */
 211         struct disk_events *ev;
 212 #ifdef  CONFIG_BLK_DEV_INTEGRITY
 213         struct kobject integrity_kobj;
 214 #endif  /* CONFIG_BLK_DEV_INTEGRITY */
 215         int node_id;
 216 };
 217
 218 static inline struct gendisk *part_to_disk(struct hd_struct *part)
 219 {
 220         if (likely(part)) {
 221                 if (part->partno)
 222                         return dev_to_disk(part_to_dev(part)->parent);
 223                 else
 224                         return dev_to_disk(part_to_dev(part));
 225         }
 226         return NULL;
 227 }
 228
 229 static inline void part_pack_uuid(const u8 *uuid_str, u8 *to)
 230 {
 231         int i;
 232         for (i = 0; i < 16; ++i) {
 233                 *to++ = (hex_to_bin(*uuid_str) << 4) |
 234                         (hex_to_bin(*(uuid_str + 1)));
 235                 uuid_str += 2;
 236                 switch (i) {
 237                 case 3:
 238                 case 5:
 239                 case 7:
 240                 case 9:
 241                         uuid_str++;
 242                         continue;
 243                 }
 244         }
 245 }
 246
 247 static inline int blk_part_pack_uuid(const u8 *uuid_str, u8 *to)
 248 {
 249         part_pack_uuid(uuid_str, to);
 250         return 0;
 251 }
 252
 253 static inline int disk_max_parts(struct gendisk *disk)
 254 {
 255         if (disk->flags & GENHD_FL_EXT_DEVT)
 256                 return DISK_MAX_PARTS;
 257         return disk->minors;
 258 }
 259
 260 static inline bool disk_part_scan_enabled(struct gendisk *disk)
 261 {
 262         return disk_max_parts(disk) > 1 &&
 263                 !(disk->flags & GENHD_FL_NO_PART_SCAN);
 264 }
 265
 266 static inline dev_t disk_devt(struct gendisk *disk)
 267 {
 268         return disk_to_dev(disk)->devt;
 269 }
 270
 271 static inline dev_t part_devt(struct hd_struct *part)
 272 {
 273         return part_to_dev(part)->devt;
 274 }
 275
 276 extern struct hd_struct *disk_get_part(struct gendisk *disk, int partno);
 277
 278 static inline void disk_put_part(struct hd_struct *part)
 279 {
 280         if (likely(part))
 281                 put_device(part_to_dev(part));
 282 }
 283
 284 /*
 285  * Smarter partition iterator without context limits.
 286  */
 287 #define DISK_PITER_REVERSE      (1 << 0) /* iterate in the reverse direction */
 288 #define DISK_PITER_INCL_EMPTY   (1 << 1) /* include 0-sized parts */
 289 #define DISK_PITER_INCL_PART0   (1 << 2) /* include partition 0 */
 290 #define DISK_PITER_INCL_EMPTY_PART0 (1 << 3) /* include empty partition 0 */
 291
 292 struct disk_part_iter {
 293         struct gendisk          *disk;
 294         struct hd_struct        *part;
 295         int                     idx;
 296         unsigned int            flags;
 297 };
 298
 299 extern void disk_part_iter_init(struct disk_part_iter *piter,
 300                                  struct gendisk *disk, unsigned int flags);
 301 extern struct hd_struct *disk_part_iter_next(struct disk_part_iter *piter);
 302 extern void disk_part_iter_exit(struct disk_part_iter *piter);
 303
 304 extern struct hd_struct *disk_map_sector_rcu(struct gendisk *disk,
 305                                              sector_t sector);
 306
 307 /*
 308  * Macros to operate on percpu disk statistics:
 309  *
 310  * {disk|part|all}_stat_{add|sub|inc|dec}() modify the stat counters
 311  * and should be called between disk_stat_lock() and
 312  * disk_stat_unlock().
 313  *
 314  * part_stat_read() can be called at any time.
 315  *
 316  * part_stat_{add|set_all}() and {init|free}_part_stats are for
 317  * internal use only.
 318  */
 319 #ifdef  CONFIG_SMP
 320 #define part_stat_lock()        ({ rcu_read_lock(); get_cpu(); })
 321 #define part_stat_unlock()      do { put_cpu(); rcu_read_unlock(); } while (0)
 322
 323 #define __part_stat_add(cpu, part, field, addnd)                        \
 324         (per_cpu_ptr((part)->dkstats, (cpu))->field += (addnd))
 325
 326 #define part_stat_read(part, field)                                     \
 327 ({                                                                      \
 328         typeof((part)->dkstats->field) res = 0;                         \
 329         unsigned int _cpu;                                              \
 330         for_each_possible_cpu(_cpu)                                     \
 331                 res += per_cpu_ptr((part)->dkstats, _cpu)->field;       \
 332         res;                                                            \
 333 })
 334
 335 static inline void part_stat_set_all(struct hd_struct *part, int value)
 336 {
 337         int i;
 338
 339         for_each_possible_cpu(i)
 340                 memset(per_cpu_ptr(part->dkstats, i), value,
 341                                 sizeof(struct disk_stats));
 342 }
 343
 344 static inline int init_part_stats(struct hd_struct *part)
 345 {
 346         part->dkstats = alloc_percpu(struct disk_stats);
 347         if (!part->dkstats)
 348                 return 0;
 349         return 1;
 350 }
 351
 352 static inline void free_part_stats(struct hd_struct *part)
 353 {
 354         free_percpu(part->dkstats);
 355 }
 356
 357 #else /* !CONFIG_SMP */
 358 #define part_stat_lock()        ({ rcu_read_lock(); 0; })
 359 #define part_stat_unlock()      rcu_read_unlock()
 360
 361 #define __part_stat_add(cpu, part, field, addnd)                                \
 362         ((part)->dkstats.field += addnd)
 363
 364 #define part_stat_read(part, field)     ((part)->dkstats.field)
 365
 366 static inline void part_stat_set_all(struct hd_struct *part, int value)
 367 {
 368         memset(&part->dkstats, value, sizeof(struct disk_stats));
 369 }
 370
 371 static inline int init_part_stats(struct hd_struct *part)
 372 {
 373         return 1;
 374 }
 375
 376 static inline void free_part_stats(struct hd_struct *part)
 377 {
 378 }
 379
 380 #endif /* CONFIG_SMP */
 381
 382 #define part_stat_add(cpu, part, field, addnd)  do {                    \
 383         __part_stat_add((cpu), (part), field, addnd);                   \
 384         if ((part)->partno)                                             \
 385                 __part_stat_add((cpu), &part_to_disk((part))->part0,    \
 386                                 field, addnd);                          \
 387 } while (0)
 388
 389 #define part_stat_dec(cpu, gendiskp, field)                             \
 390         part_stat_add(cpu, gendiskp, field, -1)
 391 #define part_stat_inc(cpu, gendiskp, field)                             \
 392         part_stat_add(cpu, gendiskp, field, 1)
 393 #define part_stat_sub(cpu, gendiskp, field, subnd)                      \
 394         part_stat_add(cpu, gendiskp, field, -subnd)
 395
 396 static inline void part_inc_in_flight(struct hd_struct *part, int rw)
 397 {
 398         atomic_inc(&part->in_flight[rw]);
 399         if (part->partno)
 400                 atomic_inc(&part_to_disk(part)->part0.in_flight[rw]);
 401 }
 402
 403 static inline void part_dec_in_flight(struct hd_struct *part, int rw)
 404 {
 405         atomic_dec(&part->in_flight[rw]);
 406         if (part->partno)
 407                 atomic_dec(&part_to_disk(part)->part0.in_flight[rw]);
 408 }
 409
 410 static inline int part_in_flight(struct hd_struct *part)
 411 {
 412         return atomic_read(&part->in_flight[0]) + atomic_read(&part->in_flight[1]);
 413 }
 414
 415 static inline struct partition_meta_info *alloc_part_info(struct gendisk *disk)
 416 {
 417         if (disk)
 418                 return kzalloc_node(sizeof(struct partition_meta_info),
 419                                     GFP_KERNEL, disk->node_id);
 420         return kzalloc(sizeof(struct partition_meta_info), GFP_KERNEL);
 421 }
 422
 423 static inline void free_part_info(struct hd_struct *part)
 424 {
 425         kfree(part->info);
 426 }
 427
 428 /* block/blk-core.c */
 429 extern void part_round_stats(int cpu, struct hd_struct *part);
 430
 431 /* block/genhd.c */
 432 extern void add_disk(struct gendisk *disk);
 433 extern void del_gendisk(struct gendisk *gp);
 434 extern struct gendisk *get_gendisk(dev_t dev, int *partno);
 435 extern struct block_device *bdget_disk(struct gendisk *disk, int partno);
 436
 437 extern void set_device_ro(struct block_device *bdev, int flag);
 438 extern void set_disk_ro(struct gendisk *disk, int flag);
 439
 440 static inline int get_disk_ro(struct gendisk *disk)
 441 {
 442         return disk->part0.policy;
 443 }
 444
 445 extern void disk_block_events(struct gendisk *disk);
 446 extern void disk_unblock_events(struct gendisk *disk);
 447 extern void disk_flush_events(struct gendisk *disk, unsigned int mask);
 448 extern unsigned int disk_clear_events(struct gendisk *disk, unsigned int mask);
 449
 450 /* drivers/char/random.c */
 451 extern void add_disk_randomness(struct gendisk *disk);
 452 extern void rand_initialize_disk(struct gendisk *disk);
 453
 454 static inline sector_t get_start_sect(struct block_device *bdev)
 455 {
 456         return bdev->bd_part->start_sect;
 457 }
 458 static inline sector_t get_capacity(struct gendisk *disk)
 459 {
 460         return disk->part0.nr_sects;
 461 }
 462 static inline void set_capacity(struct gendisk *disk, sector_t size)
 463 {
 464         disk->part0.nr_sects = size;
 465 }
 466
 467 #ifdef CONFIG_SOLARIS_X86_PARTITION
 468
 469 #define SOLARIS_X86_NUMSLICE    16
 470 #define SOLARIS_X86_VTOC_SANE   (0x600DDEEEUL)
 471
 472 struct solaris_x86_slice {
 473         __le16 s_tag;           /* ID tag of partition */
 474         __le16 s_flag;          /* permission flags */
 475         __le32 s_start;         /* start sector no of partition */
 476         __le32 s_size;          /* # of blocks in partition */
 477 };
 478
 479 struct solaris_x86_vtoc {
 480         unsigned int v_bootinfo[3];     /* info needed by mboot (unsupported) */
 481         __le32 v_sanity;                /* to verify vtoc sanity */
 482         __le32 v_version;               /* layout version */
 483         char    v_volume[8];            /* volume name */
 484         __le16  v_sectorsz;             /* sector size in bytes */
 485         __le16  v_nparts;               /* number of partitions */
 486         unsigned int v_reserved[10];    /* free space */
 487         struct solaris_x86_slice
 488                 v_slice[SOLARIS_X86_NUMSLICE]; /* slice headers */
 489         unsigned int timestamp[SOLARIS_X86_NUMSLICE]; /* timestamp (unsupported) */
 490         char    v_asciilabel[128];      /* for compatibility */
 491 };
 492
 493 #endif /* CONFIG_SOLARIS_X86_PARTITION */
 494
 495 #ifdef CONFIG_BSD_DISKLABEL
 496 /*
 497  * BSD disklabel support by Yossi Gottlieb <yogo@math.tau.ac.il>
 498  * updated by Marc Espie <Marc.Espie@openbsd.org>
 499  */
 500
 501 /* check against BSD src/sys/sys/disklabel.h for consistency */
 502
 503 #define BSD_DISKMAGIC   (0x82564557UL)  /* The disk magic number */
 504 #define BSD_MAXPARTITIONS       16
 505 #define OPENBSD_MAXPARTITIONS   16
 506 #define BSD_FS_UNUSED           0       /* disklabel unused partition entry ID */
 507 struct bsd_disklabel {
 508         __le32  d_magic;                /* the magic number */
 509         __s16   d_type;                 /* drive type */
 510         __s16   d_subtype;              /* controller/d_type specific */
 511         char    d_typename[16];         /* type name, e.g. "eagle" */
 512         char    d_packname[16];                 /* pack identifier */
 513         __u32   d_secsize;              /* # of bytes per sector */
 514         __u32   d_nsectors;             /* # of data sectors per track */
 515         __u32   d_ntracks;              /* # of tracks per cylinder */
 516         __u32   d_ncylinders;           /* # of data cylinders per unit */
 517         __u32   d_secpercyl;            /* # of data sectors per cylinder */
 518         __u32   d_secperunit;           /* # of data sectors per unit */
 519         __u16   d_sparespertrack;       /* # of spare sectors per track */
 520         __u16   d_sparespercyl;         /* # of spare sectors per cylinder */
 521         __u32   d_acylinders;           /* # of alt. cylinders per unit */
 522         __u16   d_rpm;                  /* rotational speed */
 523         __u16   d_interleave;           /* hardware sector interleave */
 524         __u16   d_trackskew;            /* sector 0 skew, per track */
 525         __u16   d_cylskew;              /* sector 0 skew, per cylinder */
 526         __u32   d_headswitch;           /* head switch time, usec */
 527         __u32   d_trkseek;              /* track-to-track seek, usec */
 528         __u32   d_flags;                /* generic flags */
 529 #define NDDATA 5
 530         __u32   d_drivedata[NDDATA];    /* drive-type specific information */
 531 #define NSPARE 5
 532         __u32   d_spare[NSPARE];        /* reserved for future use */
 533         __le32  d_magic2;               /* the magic number (again) */
 534         __le16  d_checksum;             /* xor of data incl. partitions */
 535
 536                         /* filesystem and partition information: */
 537         __le16  d_npartitions;          /* number of partitions in following */
 538         __le32  d_bbsize;               /* size of boot area at sn0, bytes */
 539         __le32  d_sbsize;               /* max size of fs superblock, bytes */
 540         struct  bsd_partition {         /* the partition table */
 541                 __le32  p_size;         /* number of sectors in partition */
 542                 __le32  p_offset;       /* starting sector */
 543                 __le32  p_fsize;        /* filesystem basic fragment size */
 544                 __u8    p_fstype;       /* filesystem type, see below */
 545                 __u8    p_frag;         /* filesystem fragments per block */
 546                 __le16  p_cpg;          /* filesystem cylinders per group */
 547         } d_partitions[BSD_MAXPARTITIONS];      /* actually may be more */
 548 };
 549
 550 #endif  /* CONFIG_BSD_DISKLABEL */
 551
 552 #ifdef CONFIG_UNIXWARE_DISKLABEL
 553 /*
 554  * Unixware slices support by Andrzej Krzysztofowicz <ankry@mif.pg.gda.pl>
 555  * and Krzysztof G. Baranowski <kgb@knm.org.pl>
 556  */
 557
 558 #define UNIXWARE_DISKMAGIC     (0xCA5E600DUL)   /* The disk magic number */
 559 #define UNIXWARE_DISKMAGIC2    (0x600DDEEEUL)   /* The slice table magic nr */
 560 #define UNIXWARE_NUMSLICE      16
 561 #define UNIXWARE_FS_UNUSED     0                /* Unused slice entry ID */
 562
 563 struct unixware_slice {
 564         __le16   s_label;       /* label */
 565         __le16   s_flags;       /* permission flags */
 566         __le32   start_sect;    /* starting sector */
 567         __le32   nr_sects;      /* number of sectors in slice */
 568 };
 569
 570 struct unixware_disklabel {
 571         __le32   d_type;                /* drive type */
 572         __le32   d_magic;                /* the magic number */
 573         __le32   d_version;              /* version number */
 574         char    d_serial[12];           /* serial number of the device */
 575         __le32   d_ncylinders;           /* # of data cylinders per device */
 576         __le32   d_ntracks;              /* # of tracks per cylinder */
 577         __le32   d_nsectors;             /* # of data sectors per track */
 578         __le32   d_secsize;              /* # of bytes per sector */
 579         __le32   d_part_start;           /* # of first sector of this partition */
 580         __le32   d_unknown1[12];         /* ? */
 581         __le32  d_alt_tbl;              /* byte offset of alternate table */
 582         __le32  d_alt_len;              /* byte length of alternate table */
 583         __le32  d_phys_cyl;             /* # of physical cylinders per device */
 584         __le32  d_phys_trk;             /* # of physical tracks per cylinder */
 585         __le32  d_phys_sec;             /* # of physical sectors per track */
 586         __le32  d_phys_bytes;           /* # of physical bytes per sector */
 587         __le32  d_unknown2;             /* ? */
 588         __le32   d_unknown3;             /* ? */
 589         __le32  d_pad[8];               /* pad */
 590
 591         struct unixware_vtoc {
 592                 __le32  v_magic;                /* the magic number */
 593                 __le32  v_version;              /* version number */
 594                 char    v_name[8];              /* volume name */
 595                 __le16  v_nslices;              /* # of slices */
 596                 __le16  v_unknown1;             /* ? */
 597                 __le32  v_reserved[10];         /* reserved */
 598                 struct unixware_slice
 599                         v_slice[UNIXWARE_NUMSLICE];     /* slice headers */
 600         } vtoc;
 601
 602 };  /* 408 */
 603
 604 #endif /* CONFIG_UNIXWARE_DISKLABEL */
 605
 606 #ifdef CONFIG_MINIX_SUBPARTITION
 607 #   define MINIX_NR_SUBPARTITIONS  4
 608 #endif /* CONFIG_MINIX_SUBPARTITION */
 609
 610 #define ADDPART_FLAG_NONE       0
 611 #define ADDPART_FLAG_RAID       1
 612 #define ADDPART_FLAG_WHOLEDISK  2
 613
 614 extern int blk_alloc_devt(struct hd_struct *part, dev_t *devt);
 615 extern void blk_free_devt(dev_t devt);
 616 extern dev_t blk_lookup_devt(const char *name, int partno);
 617 extern char *disk_name (struct gendisk *hd, int partno, char *buf);
 618
 619 extern int disk_expand_part_tbl(struct gendisk *disk, int target);
 620 extern int rescan_partitions(struct gendisk *disk, struct block_device *bdev);
 621 extern int invalidate_partitions(struct gendisk *disk, struct block_device *bdev);
 622 extern struct hd_struct * __must_check add_partition(struct gendisk *disk,
 623                                                      int partno, sector_t start,
 624                                                      sector_t len, int flags,
 625                                                      struct partition_meta_info
 626                                                        *info);
 627 extern void __delete_partition(struct percpu_ref *);
 628 extern void delete_partition(struct gendisk *, int);
 629 extern void printk_all_partitions(void);
 630
 631 extern struct gendisk *alloc_disk_node(int minors, int node_id);
 632 extern struct gendisk *alloc_disk(int minors);
 633 extern struct kobject *get_disk(struct gendisk *disk);
 634 extern void put_disk(struct gendisk *disk);
 635 extern void blk_register_region(dev_t devt, unsigned long range,
 636                         struct module *module,
 637                         struct kobject *(*probe)(dev_t, int *, void *),
 638                         int (*lock)(dev_t, void *),
 639                         void *data);
 640 extern void blk_unregister_region(dev_t devt, unsigned long range);
 641
 642 extern ssize_t part_size_show(struct device *dev,
 643                               struct device_attribute *attr, char *buf);
 644 extern ssize_t part_stat_show(struct device *dev,
 645                               struct device_attribute *attr, char *buf);
 646 extern ssize_t part_inflight_show(struct device *dev,
 647                               struct device_attribute *attr, char *buf);
 648 #ifdef CONFIG_FAIL_MAKE_REQUEST
 649 extern ssize_t part_fail_show(struct device *dev,
 650                               struct device_attribute *attr, char *buf);
 651 extern ssize_t part_fail_store(struct device *dev,
 652                                struct device_attribute *attr,
 653                                const char *buf, size_t count);
 654 #endif /* CONFIG_FAIL_MAKE_REQUEST */
 655
 656 static inline int hd_ref_init(struct hd_struct *part)
 657 {
 658         if (percpu_ref_init(&part->ref, __delete_partition, 0,
 659                                 GFP_KERNEL))
 660                 return -ENOMEM;
 661         return 0;
 662 }
 663
 664 static inline void hd_struct_get(struct hd_struct *part)
 665 {
 666         percpu_ref_get(&part->ref);
 667 }
 668
 669 static inline int hd_struct_try_get(struct hd_struct *part)
 670 {
 671         return percpu_ref_tryget_live(&part->ref);
 672 }
 673
 674 static inline void hd_struct_put(struct hd_struct *part)
 675 {
 676         percpu_ref_put(&part->ref);
 677 }
 678
 679 static inline void hd_struct_kill(struct hd_struct *part)
 680 {
 681         percpu_ref_kill(&part->ref);
 682 }
 683
 684 static inline void hd_free_part(struct hd_struct *part)
 685 {
 686         free_part_stats(part);
 687         free_part_info(part);
 688         percpu_ref_exit(&part->ref);
 689 }
 690
 691 /*
 692  * Any access of part->nr_sects which is not protected by partition
 693  * bd_mutex or gendisk bdev bd_mutex, should be done using this
 694  * accessor function.
 695  *
 696  * Code written along the lines of i_size_read() and i_size_write().
 697  * CONFIG_PREEMPT case optimizes the case of UP kernel with preemption
 698  * on.
 699  */
 700 static inline sector_t part_nr_sects_read(struct hd_struct *part)
 701 {
 702 #if BITS_PER_LONG==32 && defined(CONFIG_LBDAF) && defined(CONFIG_SMP)
 703         sector_t nr_sects;
 704         unsigned seq;
 705         do {
 706                 seq = read_seqcount_begin(&part->nr_sects_seq);
 707                 nr_sects = part->nr_sects;
 708         } while (read_seqcount_retry(&part->nr_sects_seq, seq));
 709         return nr_sects;
 710 #elif BITS_PER_LONG==32 && defined(CONFIG_LBDAF) && defined(CONFIG_PREEMPT)
 711         sector_t nr_sects;
 712
 713         preempt_disable();
 714         nr_sects = part->nr_sects;
 715         preempt_enable();
 716         return nr_sects;
 717 #else
 718         return part->nr_sects;
 719 #endif
 720 }
 721
 722 /*
 723  * Should be called with mutex lock held (typically bd_mutex) of partition
 724  * to provide mutual exlusion among writers otherwise seqcount might be
 725  * left in wrong state leaving the readers spinning infinitely.
 726  */
 727 static inline void part_nr_sects_write(struct hd_struct *part, sector_t size)
 728 {
 729 #if BITS_PER_LONG==32 && defined(CONFIG_LBDAF) && defined(CONFIG_SMP)
 730         write_seqcount_begin(&part->nr_sects_seq);
 731         part->nr_sects = size;
 732         write_seqcount_end(&part->nr_sects_seq);
 733 #elif BITS_PER_LONG==32 && defined(CONFIG_LBDAF) && defined(CONFIG_PREEMPT)
 734         preempt_disable();
 735         part->nr_sects = size;
 736         preempt_enable();
 737 #else
 738         part->nr_sects = size;
 739 #endif
 740 }
 741
 742 #if defined(CONFIG_BLK_DEV_INTEGRITY)
 743 extern void blk_integrity_add(struct gendisk *);
 744 extern void blk_integrity_del(struct gendisk *);
 745 extern void blk_integrity_revalidate(struct gendisk *);
 746 #else   /* CONFIG_BLK_DEV_INTEGRITY */
 747 static inline void blk_integrity_add(struct gendisk *disk) { }
 748 static inline void blk_integrity_del(struct gendisk *disk) { }
 749 static inline void blk_integrity_revalidate(struct gendisk *disk) { }
 750 #endif  /* CONFIG_BLK_DEV_INTEGRITY */
 751
 752 #else /* CONFIG_BLOCK */
 753
 754 static inline void printk_all_partitions(void) { }
 755
 756 static inline dev_t blk_lookup_devt(const char *name, int partno)
 757 {
 758         dev_t devt = MKDEV(0, 0);
 759         return devt;
 760 }
 761
 762 static inline int blk_part_pack_uuid(const u8 *uuid_str, u8 *to)
 763 {
 764         return -EINVAL;
 765 }
 766 #endif /* CONFIG_BLOCK */
 767
 768 #endif /* _LINUX_GENHD_H */