linux/include/linux/genhd.h
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   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
  26extern struct device_type part_type;
  27extern struct kobject *block_depr;
  28extern struct class block_class;
  29
  30enum {
  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
  70struct 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
  83struct 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
  99struct partition_meta_info {
 100        char uuid[PARTITION_META_INFO_UUIDLTH];
 101        u8 volname[PARTITION_META_INFO_VOLNAMELTH];
 102};
 103
 104struct 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
 144enum {
 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
 152struct 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
 158struct 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
 165struct disk_events;
 166struct badblocks;
 167
 168#if defined(CONFIG_BLK_DEV_INTEGRITY)
 169
 170struct 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
 180struct 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 kobject *slave_dir;
 209
 210        struct timer_rand_state *random;
 211        atomic_t sync_io;               /* RAID */
 212        struct disk_events *ev;
 213#ifdef  CONFIG_BLK_DEV_INTEGRITY
 214        struct kobject integrity_kobj;
 215#endif  /* CONFIG_BLK_DEV_INTEGRITY */
 216        int node_id;
 217        struct badblocks *bb;
 218};
 219
 220static inline struct gendisk *part_to_disk(struct hd_struct *part)
 221{
 222        if (likely(part)) {
 223                if (part->partno)
 224                        return dev_to_disk(part_to_dev(part)->parent);
 225                else
 226                        return dev_to_disk(part_to_dev(part));
 227        }
 228        return NULL;
 229}
 230
 231static inline int blk_part_pack_uuid(const u8 *uuid_str, u8 *to)
 232{
 233        uuid_be_to_bin(uuid_str, (uuid_be *)to);
 234        return 0;
 235}
 236
 237static inline int disk_max_parts(struct gendisk *disk)
 238{
 239        if (disk->flags & GENHD_FL_EXT_DEVT)
 240                return DISK_MAX_PARTS;
 241        return disk->minors;
 242}
 243
 244static inline bool disk_part_scan_enabled(struct gendisk *disk)
 245{
 246        return disk_max_parts(disk) > 1 &&
 247                !(disk->flags & GENHD_FL_NO_PART_SCAN);
 248}
 249
 250static inline dev_t disk_devt(struct gendisk *disk)
 251{
 252        return disk_to_dev(disk)->devt;
 253}
 254
 255static inline dev_t part_devt(struct hd_struct *part)
 256{
 257        return part_to_dev(part)->devt;
 258}
 259
 260extern struct hd_struct *disk_get_part(struct gendisk *disk, int partno);
 261
 262static inline void disk_put_part(struct hd_struct *part)
 263{
 264        if (likely(part))
 265                put_device(part_to_dev(part));
 266}
 267
 268/*
 269 * Smarter partition iterator without context limits.
 270 */
 271#define DISK_PITER_REVERSE      (1 << 0) /* iterate in the reverse direction */
 272#define DISK_PITER_INCL_EMPTY   (1 << 1) /* include 0-sized parts */
 273#define DISK_PITER_INCL_PART0   (1 << 2) /* include partition 0 */
 274#define DISK_PITER_INCL_EMPTY_PART0 (1 << 3) /* include empty partition 0 */
 275
 276struct disk_part_iter {
 277        struct gendisk          *disk;
 278        struct hd_struct        *part;
 279        int                     idx;
 280        unsigned int            flags;
 281};
 282
 283extern void disk_part_iter_init(struct disk_part_iter *piter,
 284                                 struct gendisk *disk, unsigned int flags);
 285extern struct hd_struct *disk_part_iter_next(struct disk_part_iter *piter);
 286extern void disk_part_iter_exit(struct disk_part_iter *piter);
 287
 288extern struct hd_struct *disk_map_sector_rcu(struct gendisk *disk,
 289                                             sector_t sector);
 290
 291/*
 292 * Macros to operate on percpu disk statistics:
 293 *
 294 * {disk|part|all}_stat_{add|sub|inc|dec}() modify the stat counters
 295 * and should be called between disk_stat_lock() and
 296 * disk_stat_unlock().
 297 *
 298 * part_stat_read() can be called at any time.
 299 *
 300 * part_stat_{add|set_all}() and {init|free}_part_stats are for
 301 * internal use only.
 302 */
 303#ifdef  CONFIG_SMP
 304#define part_stat_lock()        ({ rcu_read_lock(); get_cpu(); })
 305#define part_stat_unlock()      do { put_cpu(); rcu_read_unlock(); } while (0)
 306
 307#define __part_stat_add(cpu, part, field, addnd)                        \
 308        (per_cpu_ptr((part)->dkstats, (cpu))->field += (addnd))
 309
 310#define part_stat_read(part, field)                                     \
 311({                                                                      \
 312        typeof((part)->dkstats->field) res = 0;                         \
 313        unsigned int _cpu;                                              \
 314        for_each_possible_cpu(_cpu)                                     \
 315                res += per_cpu_ptr((part)->dkstats, _cpu)->field;       \
 316        res;                                                            \
 317})
 318
 319static inline void part_stat_set_all(struct hd_struct *part, int value)
 320{
 321        int i;
 322
 323        for_each_possible_cpu(i)
 324                memset(per_cpu_ptr(part->dkstats, i), value,
 325                                sizeof(struct disk_stats));
 326}
 327
 328static inline int init_part_stats(struct hd_struct *part)
 329{
 330        part->dkstats = alloc_percpu(struct disk_stats);
 331        if (!part->dkstats)
 332                return 0;
 333        return 1;
 334}
 335
 336static inline void free_part_stats(struct hd_struct *part)
 337{
 338        free_percpu(part->dkstats);
 339}
 340
 341#else /* !CONFIG_SMP */
 342#define part_stat_lock()        ({ rcu_read_lock(); 0; })
 343#define part_stat_unlock()      rcu_read_unlock()
 344
 345#define __part_stat_add(cpu, part, field, addnd)                                \
 346        ((part)->dkstats.field += addnd)
 347
 348#define part_stat_read(part, field)     ((part)->dkstats.field)
 349
 350static inline void part_stat_set_all(struct hd_struct *part, int value)
 351{
 352        memset(&part->dkstats, value, sizeof(struct disk_stats));
 353}
 354
 355static inline int init_part_stats(struct hd_struct *part)
 356{
 357        return 1;
 358}
 359
 360static inline void free_part_stats(struct hd_struct *part)
 361{
 362}
 363
 364#endif /* CONFIG_SMP */
 365
 366#define part_stat_add(cpu, part, field, addnd)  do {                    \
 367        __part_stat_add((cpu), (part), field, addnd);                   \
 368        if ((part)->partno)                                             \
 369                __part_stat_add((cpu), &part_to_disk((part))->part0,    \
 370                                field, addnd);                          \
 371} while (0)
 372
 373#define part_stat_dec(cpu, gendiskp, field)                             \
 374        part_stat_add(cpu, gendiskp, field, -1)
 375#define part_stat_inc(cpu, gendiskp, field)                             \
 376        part_stat_add(cpu, gendiskp, field, 1)
 377#define part_stat_sub(cpu, gendiskp, field, subnd)                      \
 378        part_stat_add(cpu, gendiskp, field, -subnd)
 379
 380static inline void part_inc_in_flight(struct hd_struct *part, int rw)
 381{
 382        atomic_inc(&part->in_flight[rw]);
 383        if (part->partno)
 384                atomic_inc(&part_to_disk(part)->part0.in_flight[rw]);
 385}
 386
 387static inline void part_dec_in_flight(struct hd_struct *part, int rw)
 388{
 389        atomic_dec(&part->in_flight[rw]);
 390        if (part->partno)
 391                atomic_dec(&part_to_disk(part)->part0.in_flight[rw]);
 392}
 393
 394static inline int part_in_flight(struct hd_struct *part)
 395{
 396        return atomic_read(&part->in_flight[0]) + atomic_read(&part->in_flight[1]);
 397}
 398
 399static inline struct partition_meta_info *alloc_part_info(struct gendisk *disk)
 400{
 401        if (disk)
 402                return kzalloc_node(sizeof(struct partition_meta_info),
 403                                    GFP_KERNEL, disk->node_id);
 404        return kzalloc(sizeof(struct partition_meta_info), GFP_KERNEL);
 405}
 406
 407static inline void free_part_info(struct hd_struct *part)
 408{
 409        kfree(part->info);
 410}
 411
 412/* block/blk-core.c */
 413extern void part_round_stats(int cpu, struct hd_struct *part);
 414
 415/* block/genhd.c */
 416extern void device_add_disk(struct device *parent, struct gendisk *disk);
 417static inline void add_disk(struct gendisk *disk)
 418{
 419        device_add_disk(NULL, disk);
 420}
 421
 422extern void del_gendisk(struct gendisk *gp);
 423extern struct gendisk *get_gendisk(dev_t dev, int *partno);
 424extern struct block_device *bdget_disk(struct gendisk *disk, int partno);
 425
 426extern void set_device_ro(struct block_device *bdev, int flag);
 427extern void set_disk_ro(struct gendisk *disk, int flag);
 428
 429static inline int get_disk_ro(struct gendisk *disk)
 430{
 431        return disk->part0.policy;
 432}
 433
 434extern void disk_block_events(struct gendisk *disk);
 435extern void disk_unblock_events(struct gendisk *disk);
 436extern void disk_flush_events(struct gendisk *disk, unsigned int mask);
 437extern unsigned int disk_clear_events(struct gendisk *disk, unsigned int mask);
 438
 439/* drivers/char/random.c */
 440extern void add_disk_randomness(struct gendisk *disk) __latent_entropy;
 441extern void rand_initialize_disk(struct gendisk *disk);
 442
 443static inline sector_t get_start_sect(struct block_device *bdev)
 444{
 445        return bdev->bd_part->start_sect;
 446}
 447static inline sector_t get_capacity(struct gendisk *disk)
 448{
 449        return disk->part0.nr_sects;
 450}
 451static inline void set_capacity(struct gendisk *disk, sector_t size)
 452{
 453        disk->part0.nr_sects = size;
 454}
 455
 456#ifdef CONFIG_SOLARIS_X86_PARTITION
 457
 458#define SOLARIS_X86_NUMSLICE    16
 459#define SOLARIS_X86_VTOC_SANE   (0x600DDEEEUL)
 460
 461struct solaris_x86_slice {
 462        __le16 s_tag;           /* ID tag of partition */
 463        __le16 s_flag;          /* permission flags */
 464        __le32 s_start;         /* start sector no of partition */
 465        __le32 s_size;          /* # of blocks in partition */
 466};
 467
 468struct solaris_x86_vtoc {
 469        unsigned int v_bootinfo[3];     /* info needed by mboot (unsupported) */
 470        __le32 v_sanity;                /* to verify vtoc sanity */
 471        __le32 v_version;               /* layout version */
 472        char    v_volume[8];            /* volume name */
 473        __le16  v_sectorsz;             /* sector size in bytes */
 474        __le16  v_nparts;               /* number of partitions */
 475        unsigned int v_reserved[10];    /* free space */
 476        struct solaris_x86_slice
 477                v_slice[SOLARIS_X86_NUMSLICE]; /* slice headers */
 478        unsigned int timestamp[SOLARIS_X86_NUMSLICE]; /* timestamp (unsupported) */
 479        char    v_asciilabel[128];      /* for compatibility */
 480};
 481
 482#endif /* CONFIG_SOLARIS_X86_PARTITION */
 483
 484#ifdef CONFIG_BSD_DISKLABEL
 485/*
 486 * BSD disklabel support by Yossi Gottlieb <yogo@math.tau.ac.il>
 487 * updated by Marc Espie <Marc.Espie@openbsd.org>
 488 */
 489
 490/* check against BSD src/sys/sys/disklabel.h for consistency */
 491
 492#define BSD_DISKMAGIC   (0x82564557UL)  /* The disk magic number */
 493#define BSD_MAXPARTITIONS       16
 494#define OPENBSD_MAXPARTITIONS   16
 495#define BSD_FS_UNUSED           0       /* disklabel unused partition entry ID */
 496struct bsd_disklabel {
 497        __le32  d_magic;                /* the magic number */
 498        __s16   d_type;                 /* drive type */
 499        __s16   d_subtype;              /* controller/d_type specific */
 500        char    d_typename[16];         /* type name, e.g. "eagle" */
 501        char    d_packname[16];                 /* pack identifier */ 
 502        __u32   d_secsize;              /* # of bytes per sector */
 503        __u32   d_nsectors;             /* # of data sectors per track */
 504        __u32   d_ntracks;              /* # of tracks per cylinder */
 505        __u32   d_ncylinders;           /* # of data cylinders per unit */
 506        __u32   d_secpercyl;            /* # of data sectors per cylinder */
 507        __u32   d_secperunit;           /* # of data sectors per unit */
 508        __u16   d_sparespertrack;       /* # of spare sectors per track */
 509        __u16   d_sparespercyl;         /* # of spare sectors per cylinder */
 510        __u32   d_acylinders;           /* # of alt. cylinders per unit */
 511        __u16   d_rpm;                  /* rotational speed */
 512        __u16   d_interleave;           /* hardware sector interleave */
 513        __u16   d_trackskew;            /* sector 0 skew, per track */
 514        __u16   d_cylskew;              /* sector 0 skew, per cylinder */
 515        __u32   d_headswitch;           /* head switch time, usec */
 516        __u32   d_trkseek;              /* track-to-track seek, usec */
 517        __u32   d_flags;                /* generic flags */
 518#define NDDATA 5
 519        __u32   d_drivedata[NDDATA];    /* drive-type specific information */
 520#define NSPARE 5
 521        __u32   d_spare[NSPARE];        /* reserved for future use */
 522        __le32  d_magic2;               /* the magic number (again) */
 523        __le16  d_checksum;             /* xor of data incl. partitions */
 524
 525                        /* filesystem and partition information: */
 526        __le16  d_npartitions;          /* number of partitions in following */
 527        __le32  d_bbsize;               /* size of boot area at sn0, bytes */
 528        __le32  d_sbsize;               /* max size of fs superblock, bytes */
 529        struct  bsd_partition {         /* the partition table */
 530                __le32  p_size;         /* number of sectors in partition */
 531                __le32  p_offset;       /* starting sector */
 532                __le32  p_fsize;        /* filesystem basic fragment size */
 533                __u8    p_fstype;       /* filesystem type, see below */
 534                __u8    p_frag;         /* filesystem fragments per block */
 535                __le16  p_cpg;          /* filesystem cylinders per group */
 536        } d_partitions[BSD_MAXPARTITIONS];      /* actually may be more */
 537};
 538
 539#endif  /* CONFIG_BSD_DISKLABEL */
 540
 541#ifdef CONFIG_UNIXWARE_DISKLABEL
 542/*
 543 * Unixware slices support by Andrzej Krzysztofowicz <ankry@mif.pg.gda.pl>
 544 * and Krzysztof G. Baranowski <kgb@knm.org.pl>
 545 */
 546
 547#define UNIXWARE_DISKMAGIC     (0xCA5E600DUL)   /* The disk magic number */
 548#define UNIXWARE_DISKMAGIC2    (0x600DDEEEUL)   /* The slice table magic nr */
 549#define UNIXWARE_NUMSLICE      16
 550#define UNIXWARE_FS_UNUSED     0                /* Unused slice entry ID */
 551
 552struct unixware_slice {
 553        __le16   s_label;       /* label */
 554        __le16   s_flags;       /* permission flags */
 555        __le32   start_sect;    /* starting sector */
 556        __le32   nr_sects;      /* number of sectors in slice */
 557};
 558
 559struct unixware_disklabel {
 560        __le32   d_type;                /* drive type */
 561        __le32   d_magic;                /* the magic number */
 562        __le32   d_version;              /* version number */
 563        char    d_serial[12];           /* serial number of the device */
 564        __le32   d_ncylinders;           /* # of data cylinders per device */
 565        __le32   d_ntracks;              /* # of tracks per cylinder */
 566        __le32   d_nsectors;             /* # of data sectors per track */
 567        __le32   d_secsize;              /* # of bytes per sector */
 568        __le32   d_part_start;           /* # of first sector of this partition */
 569        __le32   d_unknown1[12];         /* ? */
 570        __le32  d_alt_tbl;              /* byte offset of alternate table */
 571        __le32  d_alt_len;              /* byte length of alternate table */
 572        __le32  d_phys_cyl;             /* # of physical cylinders per device */
 573        __le32  d_phys_trk;             /* # of physical tracks per cylinder */
 574        __le32  d_phys_sec;             /* # of physical sectors per track */
 575        __le32  d_phys_bytes;           /* # of physical bytes per sector */
 576        __le32  d_unknown2;             /* ? */
 577        __le32   d_unknown3;             /* ? */
 578        __le32  d_pad[8];               /* pad */
 579
 580        struct unixware_vtoc {
 581                __le32  v_magic;                /* the magic number */
 582                __le32  v_version;              /* version number */
 583                char    v_name[8];              /* volume name */
 584                __le16  v_nslices;              /* # of slices */
 585                __le16  v_unknown1;             /* ? */
 586                __le32  v_reserved[10];         /* reserved */
 587                struct unixware_slice
 588                        v_slice[UNIXWARE_NUMSLICE];     /* slice headers */
 589        } vtoc;
 590
 591};  /* 408 */
 592
 593#endif /* CONFIG_UNIXWARE_DISKLABEL */
 594
 595#ifdef CONFIG_MINIX_SUBPARTITION
 596#   define MINIX_NR_SUBPARTITIONS  4
 597#endif /* CONFIG_MINIX_SUBPARTITION */
 598
 599#define ADDPART_FLAG_NONE       0
 600#define ADDPART_FLAG_RAID       1
 601#define ADDPART_FLAG_WHOLEDISK  2
 602
 603extern int blk_alloc_devt(struct hd_struct *part, dev_t *devt);
 604extern void blk_free_devt(dev_t devt);
 605extern dev_t blk_lookup_devt(const char *name, int partno);
 606extern char *disk_name (struct gendisk *hd, int partno, char *buf);
 607
 608extern int disk_expand_part_tbl(struct gendisk *disk, int target);
 609extern int rescan_partitions(struct gendisk *disk, struct block_device *bdev);
 610extern int invalidate_partitions(struct gendisk *disk, struct block_device *bdev);
 611extern struct hd_struct * __must_check add_partition(struct gendisk *disk,
 612                                                     int partno, sector_t start,
 613                                                     sector_t len, int flags,
 614                                                     struct partition_meta_info
 615                                                       *info);
 616extern void __delete_partition(struct percpu_ref *);
 617extern void delete_partition(struct gendisk *, int);
 618extern void printk_all_partitions(void);
 619
 620extern struct gendisk *alloc_disk_node(int minors, int node_id);
 621extern struct gendisk *alloc_disk(int minors);
 622extern struct kobject *get_disk(struct gendisk *disk);
 623extern void put_disk(struct gendisk *disk);
 624extern void blk_register_region(dev_t devt, unsigned long range,
 625                        struct module *module,
 626                        struct kobject *(*probe)(dev_t, int *, void *),
 627                        int (*lock)(dev_t, void *),
 628                        void *data);
 629extern void blk_unregister_region(dev_t devt, unsigned long range);
 630
 631extern ssize_t part_size_show(struct device *dev,
 632                              struct device_attribute *attr, char *buf);
 633extern ssize_t part_stat_show(struct device *dev,
 634                              struct device_attribute *attr, char *buf);
 635extern ssize_t part_inflight_show(struct device *dev,
 636                              struct device_attribute *attr, char *buf);
 637#ifdef CONFIG_FAIL_MAKE_REQUEST
 638extern ssize_t part_fail_show(struct device *dev,
 639                              struct device_attribute *attr, char *buf);
 640extern ssize_t part_fail_store(struct device *dev,
 641                               struct device_attribute *attr,
 642                               const char *buf, size_t count);
 643#endif /* CONFIG_FAIL_MAKE_REQUEST */
 644
 645static inline int hd_ref_init(struct hd_struct *part)
 646{
 647        if (percpu_ref_init(&part->ref, __delete_partition, 0,
 648                                GFP_KERNEL))
 649                return -ENOMEM;
 650        return 0;
 651}
 652
 653static inline void hd_struct_get(struct hd_struct *part)
 654{
 655        percpu_ref_get(&part->ref);
 656}
 657
 658static inline int hd_struct_try_get(struct hd_struct *part)
 659{
 660        return percpu_ref_tryget_live(&part->ref);
 661}
 662
 663static inline void hd_struct_put(struct hd_struct *part)
 664{
 665        percpu_ref_put(&part->ref);
 666}
 667
 668static inline void hd_struct_kill(struct hd_struct *part)
 669{
 670        percpu_ref_kill(&part->ref);
 671}
 672
 673static inline void hd_free_part(struct hd_struct *part)
 674{
 675        free_part_stats(part);
 676        free_part_info(part);
 677        percpu_ref_exit(&part->ref);
 678}
 679
 680/*
 681 * Any access of part->nr_sects which is not protected by partition
 682 * bd_mutex or gendisk bdev bd_mutex, should be done using this
 683 * accessor function.
 684 *
 685 * Code written along the lines of i_size_read() and i_size_write().
 686 * CONFIG_PREEMPT case optimizes the case of UP kernel with preemption
 687 * on.
 688 */
 689static inline sector_t part_nr_sects_read(struct hd_struct *part)
 690{
 691#if BITS_PER_LONG==32 && defined(CONFIG_LBDAF) && defined(CONFIG_SMP)
 692        sector_t nr_sects;
 693        unsigned seq;
 694        do {
 695                seq = read_seqcount_begin(&part->nr_sects_seq);
 696                nr_sects = part->nr_sects;
 697        } while (read_seqcount_retry(&part->nr_sects_seq, seq));
 698        return nr_sects;
 699#elif BITS_PER_LONG==32 && defined(CONFIG_LBDAF) && defined(CONFIG_PREEMPT)
 700        sector_t nr_sects;
 701
 702        preempt_disable();
 703        nr_sects = part->nr_sects;
 704        preempt_enable();
 705        return nr_sects;
 706#else
 707        return part->nr_sects;
 708#endif
 709}
 710
 711/*
 712 * Should be called with mutex lock held (typically bd_mutex) of partition
 713 * to provide mutual exlusion among writers otherwise seqcount might be
 714 * left in wrong state leaving the readers spinning infinitely.
 715 */
 716static inline void part_nr_sects_write(struct hd_struct *part, sector_t size)
 717{
 718#if BITS_PER_LONG==32 && defined(CONFIG_LBDAF) && defined(CONFIG_SMP)
 719        write_seqcount_begin(&part->nr_sects_seq);
 720        part->nr_sects = size;
 721        write_seqcount_end(&part->nr_sects_seq);
 722#elif BITS_PER_LONG==32 && defined(CONFIG_LBDAF) && defined(CONFIG_PREEMPT)
 723        preempt_disable();
 724        part->nr_sects = size;
 725        preempt_enable();
 726#else
 727        part->nr_sects = size;
 728#endif
 729}
 730
 731#if defined(CONFIG_BLK_DEV_INTEGRITY)
 732extern void blk_integrity_add(struct gendisk *);
 733extern void blk_integrity_del(struct gendisk *);
 734extern void blk_integrity_revalidate(struct gendisk *);
 735#else   /* CONFIG_BLK_DEV_INTEGRITY */
 736static inline void blk_integrity_add(struct gendisk *disk) { }
 737static inline void blk_integrity_del(struct gendisk *disk) { }
 738static inline void blk_integrity_revalidate(struct gendisk *disk) { }
 739#endif  /* CONFIG_BLK_DEV_INTEGRITY */
 740
 741#else /* CONFIG_BLOCK */
 742
 743static inline void printk_all_partitions(void) { }
 744
 745static inline dev_t blk_lookup_devt(const char *name, int partno)
 746{
 747        dev_t devt = MKDEV(0, 0);
 748        return devt;
 749}
 750
 751static inline int blk_part_pack_uuid(const u8 *uuid_str, u8 *to)
 752{
 753        return -EINVAL;
 754}
 755#endif /* CONFIG_BLOCK */
 756
 757#endif /* _LINUX_GENHD_H */
 758