linux/include/linux/genhd.h
<<
>>
Prefs
   1/* SPDX-License-Identifier: GPL-2.0 */
   2#ifndef _LINUX_GENHD_H
   3#define _LINUX_GENHD_H
   4
   5/*
   6 *      genhd.h Copyright (C) 1992 Drew Eckhardt
   7 *      Generic hard disk header file by  
   8 *              Drew Eckhardt
   9 *
  10 *              <drew@colorado.edu>
  11 */
  12
  13#include <linux/types.h>
  14#include <linux/kdev_t.h>
  15#include <linux/rcupdate.h>
  16#include <linux/slab.h>
  17#include <linux/percpu-refcount.h>
  18#include <linux/uuid.h>
  19#include <linux/blk_types.h>
  20
  21#ifdef CONFIG_BLOCK
  22
  23#define dev_to_disk(device)     container_of((device), struct gendisk, part0.__dev)
  24#define dev_to_part(device)     container_of((device), struct hd_struct, __dev)
  25#define disk_to_dev(disk)       (&(disk)->part0.__dev)
  26#define part_to_dev(part)       (&((part)->__dev))
  27
  28extern struct device_type part_type;
  29extern struct kobject *block_depr;
  30extern struct class block_class;
  31
  32enum {
  33/* These three have identical behaviour; use the second one if DOS FDISK gets
  34   confused about extended/logical partitions starting past cylinder 1023. */
  35        DOS_EXTENDED_PARTITION = 5,
  36        LINUX_EXTENDED_PARTITION = 0x85,
  37        WIN98_EXTENDED_PARTITION = 0x0f,
  38
  39        SUN_WHOLE_DISK = DOS_EXTENDED_PARTITION,
  40
  41        LINUX_SWAP_PARTITION = 0x82,
  42        LINUX_DATA_PARTITION = 0x83,
  43        LINUX_LVM_PARTITION = 0x8e,
  44        LINUX_RAID_PARTITION = 0xfd,    /* autodetect RAID partition */
  45
  46        SOLARIS_X86_PARTITION = LINUX_SWAP_PARTITION,
  47        NEW_SOLARIS_X86_PARTITION = 0xbf,
  48
  49        DM6_AUX1PARTITION = 0x51,       /* no DDO:  use xlated geom */
  50        DM6_AUX3PARTITION = 0x53,       /* no DDO:  use xlated geom */
  51        DM6_PARTITION = 0x54,           /* has DDO: use xlated geom & offset */
  52        EZD_PARTITION = 0x55,           /* EZ-DRIVE */
  53
  54        FREEBSD_PARTITION = 0xa5,       /* FreeBSD Partition ID */
  55        OPENBSD_PARTITION = 0xa6,       /* OpenBSD Partition ID */
  56        NETBSD_PARTITION = 0xa9,        /* NetBSD Partition ID */
  57        BSDI_PARTITION = 0xb7,          /* BSDI Partition ID */
  58        MINIX_PARTITION = 0x81,         /* Minix Partition ID */
  59        UNIXWARE_PARTITION = 0x63,      /* Same as GNU_HURD and SCO Unix */
  60};
  61
  62#define DISK_MAX_PARTS                  256
  63#define DISK_NAME_LEN                   32
  64
  65#include <linux/major.h>
  66#include <linux/device.h>
  67#include <linux/smp.h>
  68#include <linux/string.h>
  69#include <linux/fs.h>
  70#include <linux/workqueue.h>
  71
  72struct partition {
  73        unsigned char boot_ind;         /* 0x80 - active */
  74        unsigned char head;             /* starting head */
  75        unsigned char sector;           /* starting sector */
  76        unsigned char cyl;              /* starting cylinder */
  77        unsigned char sys_ind;          /* What partition type */
  78        unsigned char end_head;         /* end head */
  79        unsigned char end_sector;       /* end sector */
  80        unsigned char end_cyl;          /* end cylinder */
  81        __le32 start_sect;      /* starting sector counting from 0 */
  82        __le32 nr_sects;                /* nr of sectors in partition */
  83} __attribute__((packed));
  84
  85struct disk_stats {
  86        u64 nsecs[NR_STAT_GROUPS];
  87        unsigned long sectors[NR_STAT_GROUPS];
  88        unsigned long ios[NR_STAT_GROUPS];
  89        unsigned long merges[NR_STAT_GROUPS];
  90        unsigned long io_ticks;
  91        unsigned long time_in_queue;
  92};
  93
  94#define PARTITION_META_INFO_VOLNAMELTH  64
  95/*
  96 * Enough for the string representation of any kind of UUID plus NULL.
  97 * EFI UUID is 36 characters. MSDOS UUID is 11 characters.
  98 */
  99#define PARTITION_META_INFO_UUIDLTH     (UUID_STRING_LEN + 1)
 100
 101struct partition_meta_info {
 102        char uuid[PARTITION_META_INFO_UUIDLTH];
 103        u8 volname[PARTITION_META_INFO_VOLNAMELTH];
 104};
 105
 106struct hd_struct {
 107        sector_t start_sect;
 108        /*
 109         * nr_sects is protected by sequence counter. One might extend a
 110         * partition while IO is happening to it and update of nr_sects
 111         * can be non-atomic on 32bit machines with 64bit sector_t.
 112         */
 113        sector_t nr_sects;
 114        seqcount_t nr_sects_seq;
 115        sector_t alignment_offset;
 116        unsigned int discard_alignment;
 117        struct device __dev;
 118        struct kobject *holder_dir;
 119        int policy, partno;
 120        struct partition_meta_info *info;
 121#ifdef CONFIG_FAIL_MAKE_REQUEST
 122        int make_it_fail;
 123#endif
 124        unsigned long stamp;
 125        atomic_t in_flight[2];
 126#ifdef  CONFIG_SMP
 127        struct disk_stats __percpu *dkstats;
 128#else
 129        struct disk_stats dkstats;
 130#endif
 131        struct percpu_ref ref;
 132        struct rcu_head rcu_head;
 133};
 134
 135#define GENHD_FL_REMOVABLE                      1
 136/* 2 is unused */
 137#define GENHD_FL_MEDIA_CHANGE_NOTIFY            4
 138#define GENHD_FL_CD                             8
 139#define GENHD_FL_UP                             16
 140#define GENHD_FL_SUPPRESS_PARTITION_INFO        32
 141#define GENHD_FL_EXT_DEVT                       64 /* allow extended devt */
 142#define GENHD_FL_NATIVE_CAPACITY                128
 143#define GENHD_FL_BLOCK_EVENTS_ON_EXCL_WRITE     256
 144#define GENHD_FL_NO_PART_SCAN                   512
 145#define GENHD_FL_HIDDEN                         1024
 146
 147enum {
 148        DISK_EVENT_MEDIA_CHANGE                 = 1 << 0, /* media changed */
 149        DISK_EVENT_EJECT_REQUEST                = 1 << 1, /* eject requested */
 150};
 151
 152struct disk_part_tbl {
 153        struct rcu_head rcu_head;
 154        int len;
 155        struct hd_struct __rcu *last_lookup;
 156        struct hd_struct __rcu *part[];
 157};
 158
 159struct disk_events;
 160struct badblocks;
 161
 162#if defined(CONFIG_BLK_DEV_INTEGRITY)
 163
 164struct blk_integrity {
 165        const struct blk_integrity_profile      *profile;
 166        unsigned char                           flags;
 167        unsigned char                           tuple_size;
 168        unsigned char                           interval_exp;
 169        unsigned char                           tag_size;
 170};
 171
 172#endif  /* CONFIG_BLK_DEV_INTEGRITY */
 173
 174struct gendisk {
 175        /* major, first_minor and minors are input parameters only,
 176         * don't use directly.  Use disk_devt() and disk_max_parts().
 177         */
 178        int major;                      /* major number of driver */
 179        int first_minor;
 180        int minors;                     /* maximum number of minors, =1 for
 181                                         * disks that can't be partitioned. */
 182
 183        char disk_name[DISK_NAME_LEN];  /* name of major driver */
 184        char *(*devnode)(struct gendisk *gd, umode_t *mode);
 185
 186        unsigned int events;            /* supported events */
 187        unsigned int async_events;      /* async events, subset of all */
 188
 189        /* Array of pointers to partitions indexed by partno.
 190         * Protected with matching bdev lock but stat and other
 191         * non-critical accesses use RCU.  Always access through
 192         * helpers.
 193         */
 194        struct disk_part_tbl __rcu *part_tbl;
 195        struct hd_struct part0;
 196
 197        const struct block_device_operations *fops;
 198        struct request_queue *queue;
 199        void *private_data;
 200
 201        int flags;
 202        struct rw_semaphore lookup_sem;
 203        struct kobject *slave_dir;
 204
 205        struct timer_rand_state *random;
 206        atomic_t sync_io;               /* RAID */
 207        struct disk_events *ev;
 208#ifdef  CONFIG_BLK_DEV_INTEGRITY
 209        struct kobject integrity_kobj;
 210#endif  /* CONFIG_BLK_DEV_INTEGRITY */
 211        int node_id;
 212        struct badblocks *bb;
 213        struct lockdep_map lockdep_map;
 214};
 215
 216static inline struct gendisk *part_to_disk(struct hd_struct *part)
 217{
 218        if (likely(part)) {
 219                if (part->partno)
 220                        return dev_to_disk(part_to_dev(part)->parent);
 221                else
 222                        return dev_to_disk(part_to_dev(part));
 223        }
 224        return NULL;
 225}
 226
 227static inline int disk_max_parts(struct gendisk *disk)
 228{
 229        if (disk->flags & GENHD_FL_EXT_DEVT)
 230                return DISK_MAX_PARTS;
 231        return disk->minors;
 232}
 233
 234static inline bool disk_part_scan_enabled(struct gendisk *disk)
 235{
 236        return disk_max_parts(disk) > 1 &&
 237                !(disk->flags & GENHD_FL_NO_PART_SCAN);
 238}
 239
 240static inline dev_t disk_devt(struct gendisk *disk)
 241{
 242        return MKDEV(disk->major, disk->first_minor);
 243}
 244
 245static inline dev_t part_devt(struct hd_struct *part)
 246{
 247        return part_to_dev(part)->devt;
 248}
 249
 250extern struct hd_struct *__disk_get_part(struct gendisk *disk, int partno);
 251extern struct hd_struct *disk_get_part(struct gendisk *disk, int partno);
 252
 253static inline void disk_put_part(struct hd_struct *part)
 254{
 255        if (likely(part))
 256                put_device(part_to_dev(part));
 257}
 258
 259/*
 260 * Smarter partition iterator without context limits.
 261 */
 262#define DISK_PITER_REVERSE      (1 << 0) /* iterate in the reverse direction */
 263#define DISK_PITER_INCL_EMPTY   (1 << 1) /* include 0-sized parts */
 264#define DISK_PITER_INCL_PART0   (1 << 2) /* include partition 0 */
 265#define DISK_PITER_INCL_EMPTY_PART0 (1 << 3) /* include empty partition 0 */
 266
 267struct disk_part_iter {
 268        struct gendisk          *disk;
 269        struct hd_struct        *part;
 270        int                     idx;
 271        unsigned int            flags;
 272};
 273
 274extern void disk_part_iter_init(struct disk_part_iter *piter,
 275                                 struct gendisk *disk, unsigned int flags);
 276extern struct hd_struct *disk_part_iter_next(struct disk_part_iter *piter);
 277extern void disk_part_iter_exit(struct disk_part_iter *piter);
 278
 279extern struct hd_struct *disk_map_sector_rcu(struct gendisk *disk,
 280                                             sector_t sector);
 281
 282/*
 283 * Macros to operate on percpu disk statistics:
 284 *
 285 * {disk|part|all}_stat_{add|sub|inc|dec}() modify the stat counters
 286 * and should be called between disk_stat_lock() and
 287 * disk_stat_unlock().
 288 *
 289 * part_stat_read() can be called at any time.
 290 *
 291 * part_stat_{add|set_all}() and {init|free}_part_stats are for
 292 * internal use only.
 293 */
 294#ifdef  CONFIG_SMP
 295#define part_stat_lock()        ({ rcu_read_lock(); get_cpu(); })
 296#define part_stat_unlock()      do { put_cpu(); rcu_read_unlock(); } while (0)
 297
 298#define __part_stat_add(cpu, part, field, addnd)                        \
 299        (per_cpu_ptr((part)->dkstats, (cpu))->field += (addnd))
 300
 301#define part_stat_read(part, field)                                     \
 302({                                                                      \
 303        typeof((part)->dkstats->field) res = 0;                         \
 304        unsigned int _cpu;                                              \
 305        for_each_possible_cpu(_cpu)                                     \
 306                res += per_cpu_ptr((part)->dkstats, _cpu)->field;       \
 307        res;                                                            \
 308})
 309
 310static inline void part_stat_set_all(struct hd_struct *part, int value)
 311{
 312        int i;
 313
 314        for_each_possible_cpu(i)
 315                memset(per_cpu_ptr(part->dkstats, i), value,
 316                                sizeof(struct disk_stats));
 317}
 318
 319static inline int init_part_stats(struct hd_struct *part)
 320{
 321        part->dkstats = alloc_percpu(struct disk_stats);
 322        if (!part->dkstats)
 323                return 0;
 324        return 1;
 325}
 326
 327static inline void free_part_stats(struct hd_struct *part)
 328{
 329        free_percpu(part->dkstats);
 330}
 331
 332#else /* !CONFIG_SMP */
 333#define part_stat_lock()        ({ rcu_read_lock(); 0; })
 334#define part_stat_unlock()      rcu_read_unlock()
 335
 336#define __part_stat_add(cpu, part, field, addnd)                                \
 337        ((part)->dkstats.field += addnd)
 338
 339#define part_stat_read(part, field)     ((part)->dkstats.field)
 340
 341static inline void part_stat_set_all(struct hd_struct *part, int value)
 342{
 343        memset(&part->dkstats, value, sizeof(struct disk_stats));
 344}
 345
 346static inline int init_part_stats(struct hd_struct *part)
 347{
 348        return 1;
 349}
 350
 351static inline void free_part_stats(struct hd_struct *part)
 352{
 353}
 354
 355#endif /* CONFIG_SMP */
 356
 357#define part_stat_read_msecs(part, which)                               \
 358        div_u64(part_stat_read(part, nsecs[which]), NSEC_PER_MSEC)
 359
 360#define part_stat_read_accum(part, field)                               \
 361        (part_stat_read(part, field[STAT_READ]) +                       \
 362         part_stat_read(part, field[STAT_WRITE]) +                      \
 363         part_stat_read(part, field[STAT_DISCARD]))
 364
 365#define part_stat_add(cpu, part, field, addnd)  do {                    \
 366        __part_stat_add((cpu), (part), field, addnd);                   \
 367        if ((part)->partno)                                             \
 368                __part_stat_add((cpu), &part_to_disk((part))->part0,    \
 369                                field, addnd);                          \
 370} while (0)
 371
 372#define part_stat_dec(cpu, gendiskp, field)                             \
 373        part_stat_add(cpu, gendiskp, field, -1)
 374#define part_stat_inc(cpu, gendiskp, field)                             \
 375        part_stat_add(cpu, gendiskp, field, 1)
 376#define part_stat_sub(cpu, gendiskp, field, subnd)                      \
 377        part_stat_add(cpu, gendiskp, field, -subnd)
 378
 379void part_in_flight(struct request_queue *q, struct hd_struct *part,
 380                    unsigned int inflight[2]);
 381void part_in_flight_rw(struct request_queue *q, struct hd_struct *part,
 382                       unsigned int inflight[2]);
 383void part_dec_in_flight(struct request_queue *q, struct hd_struct *part,
 384                        int rw);
 385void part_inc_in_flight(struct request_queue *q, struct hd_struct *part,
 386                        int rw);
 387
 388static inline struct partition_meta_info *alloc_part_info(struct gendisk *disk)
 389{
 390        if (disk)
 391                return kzalloc_node(sizeof(struct partition_meta_info),
 392                                    GFP_KERNEL, disk->node_id);
 393        return kzalloc(sizeof(struct partition_meta_info), GFP_KERNEL);
 394}
 395
 396static inline void free_part_info(struct hd_struct *part)
 397{
 398        kfree(part->info);
 399}
 400
 401/* block/blk-core.c */
 402extern void part_round_stats(struct request_queue *q, int cpu, struct hd_struct *part);
 403
 404/* block/genhd.c */
 405extern void device_add_disk(struct device *parent, struct gendisk *disk);
 406static inline void add_disk(struct gendisk *disk)
 407{
 408        device_add_disk(NULL, disk);
 409}
 410extern void device_add_disk_no_queue_reg(struct device *parent, struct gendisk *disk);
 411static inline void add_disk_no_queue_reg(struct gendisk *disk)
 412{
 413        device_add_disk_no_queue_reg(NULL, disk);
 414}
 415
 416extern void del_gendisk(struct gendisk *gp);
 417extern struct gendisk *get_gendisk(dev_t dev, int *partno);
 418extern struct block_device *bdget_disk(struct gendisk *disk, int partno);
 419
 420extern void set_device_ro(struct block_device *bdev, int flag);
 421extern void set_disk_ro(struct gendisk *disk, int flag);
 422
 423static inline int get_disk_ro(struct gendisk *disk)
 424{
 425        return disk->part0.policy;
 426}
 427
 428extern void disk_block_events(struct gendisk *disk);
 429extern void disk_unblock_events(struct gendisk *disk);
 430extern void disk_flush_events(struct gendisk *disk, unsigned int mask);
 431extern unsigned int disk_clear_events(struct gendisk *disk, unsigned int mask);
 432
 433/* drivers/char/random.c */
 434extern void add_disk_randomness(struct gendisk *disk) __latent_entropy;
 435extern void rand_initialize_disk(struct gendisk *disk);
 436
 437static inline sector_t get_start_sect(struct block_device *bdev)
 438{
 439        return bdev->bd_part->start_sect;
 440}
 441static inline sector_t get_capacity(struct gendisk *disk)
 442{
 443        return disk->part0.nr_sects;
 444}
 445static inline void set_capacity(struct gendisk *disk, sector_t size)
 446{
 447        disk->part0.nr_sects = size;
 448}
 449
 450#ifdef CONFIG_SOLARIS_X86_PARTITION
 451
 452#define SOLARIS_X86_NUMSLICE    16
 453#define SOLARIS_X86_VTOC_SANE   (0x600DDEEEUL)
 454
 455struct solaris_x86_slice {
 456        __le16 s_tag;           /* ID tag of partition */
 457        __le16 s_flag;          /* permission flags */
 458        __le32 s_start;         /* start sector no of partition */
 459        __le32 s_size;          /* # of blocks in partition */
 460};
 461
 462struct solaris_x86_vtoc {
 463        unsigned int v_bootinfo[3];     /* info needed by mboot (unsupported) */
 464        __le32 v_sanity;                /* to verify vtoc sanity */
 465        __le32 v_version;               /* layout version */
 466        char    v_volume[8];            /* volume name */
 467        __le16  v_sectorsz;             /* sector size in bytes */
 468        __le16  v_nparts;               /* number of partitions */
 469        unsigned int v_reserved[10];    /* free space */
 470        struct solaris_x86_slice
 471                v_slice[SOLARIS_X86_NUMSLICE]; /* slice headers */
 472        unsigned int timestamp[SOLARIS_X86_NUMSLICE]; /* timestamp (unsupported) */
 473        char    v_asciilabel[128];      /* for compatibility */
 474};
 475
 476#endif /* CONFIG_SOLARIS_X86_PARTITION */
 477
 478#ifdef CONFIG_BSD_DISKLABEL
 479/*
 480 * BSD disklabel support by Yossi Gottlieb <yogo@math.tau.ac.il>
 481 * updated by Marc Espie <Marc.Espie@openbsd.org>
 482 */
 483
 484/* check against BSD src/sys/sys/disklabel.h for consistency */
 485
 486#define BSD_DISKMAGIC   (0x82564557UL)  /* The disk magic number */
 487#define BSD_MAXPARTITIONS       16
 488#define OPENBSD_MAXPARTITIONS   16
 489#define BSD_FS_UNUSED           0       /* disklabel unused partition entry ID */
 490struct bsd_disklabel {
 491        __le32  d_magic;                /* the magic number */
 492        __s16   d_type;                 /* drive type */
 493        __s16   d_subtype;              /* controller/d_type specific */
 494        char    d_typename[16];         /* type name, e.g. "eagle" */
 495        char    d_packname[16];                 /* pack identifier */ 
 496        __u32   d_secsize;              /* # of bytes per sector */
 497        __u32   d_nsectors;             /* # of data sectors per track */
 498        __u32   d_ntracks;              /* # of tracks per cylinder */
 499        __u32   d_ncylinders;           /* # of data cylinders per unit */
 500        __u32   d_secpercyl;            /* # of data sectors per cylinder */
 501        __u32   d_secperunit;           /* # of data sectors per unit */
 502        __u16   d_sparespertrack;       /* # of spare sectors per track */
 503        __u16   d_sparespercyl;         /* # of spare sectors per cylinder */
 504        __u32   d_acylinders;           /* # of alt. cylinders per unit */
 505        __u16   d_rpm;                  /* rotational speed */
 506        __u16   d_interleave;           /* hardware sector interleave */
 507        __u16   d_trackskew;            /* sector 0 skew, per track */
 508        __u16   d_cylskew;              /* sector 0 skew, per cylinder */
 509        __u32   d_headswitch;           /* head switch time, usec */
 510        __u32   d_trkseek;              /* track-to-track seek, usec */
 511        __u32   d_flags;                /* generic flags */
 512#define NDDATA 5
 513        __u32   d_drivedata[NDDATA];    /* drive-type specific information */
 514#define NSPARE 5
 515        __u32   d_spare[NSPARE];        /* reserved for future use */
 516        __le32  d_magic2;               /* the magic number (again) */
 517        __le16  d_checksum;             /* xor of data incl. partitions */
 518
 519                        /* filesystem and partition information: */
 520        __le16  d_npartitions;          /* number of partitions in following */
 521        __le32  d_bbsize;               /* size of boot area at sn0, bytes */
 522        __le32  d_sbsize;               /* max size of fs superblock, bytes */
 523        struct  bsd_partition {         /* the partition table */
 524                __le32  p_size;         /* number of sectors in partition */
 525                __le32  p_offset;       /* starting sector */
 526                __le32  p_fsize;        /* filesystem basic fragment size */
 527                __u8    p_fstype;       /* filesystem type, see below */
 528                __u8    p_frag;         /* filesystem fragments per block */
 529                __le16  p_cpg;          /* filesystem cylinders per group */
 530        } d_partitions[BSD_MAXPARTITIONS];      /* actually may be more */
 531};
 532
 533#endif  /* CONFIG_BSD_DISKLABEL */
 534
 535#ifdef CONFIG_UNIXWARE_DISKLABEL
 536/*
 537 * Unixware slices support by Andrzej Krzysztofowicz <ankry@mif.pg.gda.pl>
 538 * and Krzysztof G. Baranowski <kgb@knm.org.pl>
 539 */
 540
 541#define UNIXWARE_DISKMAGIC     (0xCA5E600DUL)   /* The disk magic number */
 542#define UNIXWARE_DISKMAGIC2    (0x600DDEEEUL)   /* The slice table magic nr */
 543#define UNIXWARE_NUMSLICE      16
 544#define UNIXWARE_FS_UNUSED     0                /* Unused slice entry ID */
 545
 546struct unixware_slice {
 547        __le16   s_label;       /* label */
 548        __le16   s_flags;       /* permission flags */
 549        __le32   start_sect;    /* starting sector */
 550        __le32   nr_sects;      /* number of sectors in slice */
 551};
 552
 553struct unixware_disklabel {
 554        __le32   d_type;                /* drive type */
 555        __le32   d_magic;                /* the magic number */
 556        __le32   d_version;              /* version number */
 557        char    d_serial[12];           /* serial number of the device */
 558        __le32   d_ncylinders;           /* # of data cylinders per device */
 559        __le32   d_ntracks;              /* # of tracks per cylinder */
 560        __le32   d_nsectors;             /* # of data sectors per track */
 561        __le32   d_secsize;              /* # of bytes per sector */
 562        __le32   d_part_start;           /* # of first sector of this partition */
 563        __le32   d_unknown1[12];         /* ? */
 564        __le32  d_alt_tbl;              /* byte offset of alternate table */
 565        __le32  d_alt_len;              /* byte length of alternate table */
 566        __le32  d_phys_cyl;             /* # of physical cylinders per device */
 567        __le32  d_phys_trk;             /* # of physical tracks per cylinder */
 568        __le32  d_phys_sec;             /* # of physical sectors per track */
 569        __le32  d_phys_bytes;           /* # of physical bytes per sector */
 570        __le32  d_unknown2;             /* ? */
 571        __le32   d_unknown3;             /* ? */
 572        __le32  d_pad[8];               /* pad */
 573
 574        struct unixware_vtoc {
 575                __le32  v_magic;                /* the magic number */
 576                __le32  v_version;              /* version number */
 577                char    v_name[8];              /* volume name */
 578                __le16  v_nslices;              /* # of slices */
 579                __le16  v_unknown1;             /* ? */
 580                __le32  v_reserved[10];         /* reserved */
 581                struct unixware_slice
 582                        v_slice[UNIXWARE_NUMSLICE];     /* slice headers */
 583        } vtoc;
 584
 585};  /* 408 */
 586
 587#endif /* CONFIG_UNIXWARE_DISKLABEL */
 588
 589#ifdef CONFIG_MINIX_SUBPARTITION
 590#   define MINIX_NR_SUBPARTITIONS  4
 591#endif /* CONFIG_MINIX_SUBPARTITION */
 592
 593#define ADDPART_FLAG_NONE       0
 594#define ADDPART_FLAG_RAID       1
 595#define ADDPART_FLAG_WHOLEDISK  2
 596
 597extern int blk_alloc_devt(struct hd_struct *part, dev_t *devt);
 598extern void blk_free_devt(dev_t devt);
 599extern dev_t blk_lookup_devt(const char *name, int partno);
 600extern char *disk_name (struct gendisk *hd, int partno, char *buf);
 601
 602extern int disk_expand_part_tbl(struct gendisk *disk, int target);
 603extern int rescan_partitions(struct gendisk *disk, struct block_device *bdev);
 604extern int invalidate_partitions(struct gendisk *disk, struct block_device *bdev);
 605extern struct hd_struct * __must_check add_partition(struct gendisk *disk,
 606                                                     int partno, sector_t start,
 607                                                     sector_t len, int flags,
 608                                                     struct partition_meta_info
 609                                                       *info);
 610extern void __delete_partition(struct percpu_ref *);
 611extern void delete_partition(struct gendisk *, int);
 612extern void printk_all_partitions(void);
 613
 614extern struct gendisk *__alloc_disk_node(int minors, int node_id);
 615extern struct kobject *get_disk_and_module(struct gendisk *disk);
 616extern void put_disk(struct gendisk *disk);
 617extern void put_disk_and_module(struct gendisk *disk);
 618extern void blk_register_region(dev_t devt, unsigned long range,
 619                        struct module *module,
 620                        struct kobject *(*probe)(dev_t, int *, void *),
 621                        int (*lock)(dev_t, void *),
 622                        void *data);
 623extern void blk_unregister_region(dev_t devt, unsigned long range);
 624
 625extern ssize_t part_size_show(struct device *dev,
 626                              struct device_attribute *attr, char *buf);
 627extern ssize_t part_stat_show(struct device *dev,
 628                              struct device_attribute *attr, char *buf);
 629extern ssize_t part_inflight_show(struct device *dev,
 630                              struct device_attribute *attr, char *buf);
 631#ifdef CONFIG_FAIL_MAKE_REQUEST
 632extern ssize_t part_fail_show(struct device *dev,
 633                              struct device_attribute *attr, char *buf);
 634extern ssize_t part_fail_store(struct device *dev,
 635                               struct device_attribute *attr,
 636                               const char *buf, size_t count);
 637#endif /* CONFIG_FAIL_MAKE_REQUEST */
 638
 639#define alloc_disk_node(minors, node_id)                                \
 640({                                                                      \
 641        static struct lock_class_key __key;                             \
 642        const char *__name;                                             \
 643        struct gendisk *__disk;                                         \
 644                                                                        \
 645        __name = "(gendisk_completion)"#minors"("#node_id")";           \
 646                                                                        \
 647        __disk = __alloc_disk_node(minors, node_id);                    \
 648                                                                        \
 649        if (__disk)                                                     \
 650                lockdep_init_map(&__disk->lockdep_map, __name, &__key, 0); \
 651                                                                        \
 652        __disk;                                                         \
 653})
 654
 655#define alloc_disk(minors) alloc_disk_node(minors, NUMA_NO_NODE)
 656
 657static inline int hd_ref_init(struct hd_struct *part)
 658{
 659        if (percpu_ref_init(&part->ref, __delete_partition, 0,
 660                                GFP_KERNEL))
 661                return -ENOMEM;
 662        return 0;
 663}
 664
 665static inline void hd_struct_get(struct hd_struct *part)
 666{
 667        percpu_ref_get(&part->ref);
 668}
 669
 670static inline int hd_struct_try_get(struct hd_struct *part)
 671{
 672        return percpu_ref_tryget_live(&part->ref);
 673}
 674
 675static inline void hd_struct_put(struct hd_struct *part)
 676{
 677        percpu_ref_put(&part->ref);
 678}
 679
 680static inline void hd_struct_kill(struct hd_struct *part)
 681{
 682        percpu_ref_kill(&part->ref);
 683}
 684
 685static inline void hd_free_part(struct hd_struct *part)
 686{
 687        free_part_stats(part);
 688        free_part_info(part);
 689        percpu_ref_exit(&part->ref);
 690}
 691
 692/*
 693 * Any access of part->nr_sects which is not protected by partition
 694 * bd_mutex or gendisk bdev bd_mutex, should be done using this
 695 * accessor function.
 696 *
 697 * Code written along the lines of i_size_read() and i_size_write().
 698 * CONFIG_PREEMPT case optimizes the case of UP kernel with preemption
 699 * on.
 700 */
 701static inline sector_t part_nr_sects_read(struct hd_struct *part)
 702{
 703#if BITS_PER_LONG==32 && defined(CONFIG_LBDAF) && defined(CONFIG_SMP)
 704        sector_t nr_sects;
 705        unsigned seq;
 706        do {
 707                seq = read_seqcount_begin(&part->nr_sects_seq);
 708                nr_sects = part->nr_sects;
 709        } while (read_seqcount_retry(&part->nr_sects_seq, seq));
 710        return nr_sects;
 711#elif BITS_PER_LONG==32 && defined(CONFIG_LBDAF) && defined(CONFIG_PREEMPT)
 712        sector_t nr_sects;
 713
 714        preempt_disable();
 715        nr_sects = part->nr_sects;
 716        preempt_enable();
 717        return nr_sects;
 718#else
 719        return part->nr_sects;
 720#endif
 721}
 722
 723/*
 724 * Should be called with mutex lock held (typically bd_mutex) of partition
 725 * to provide mutual exlusion among writers otherwise seqcount might be
 726 * left in wrong state leaving the readers spinning infinitely.
 727 */
 728static inline void part_nr_sects_write(struct hd_struct *part, sector_t size)
 729{
 730#if BITS_PER_LONG==32 && defined(CONFIG_LBDAF) && defined(CONFIG_SMP)
 731        write_seqcount_begin(&part->nr_sects_seq);
 732        part->nr_sects = size;
 733        write_seqcount_end(&part->nr_sects_seq);
 734#elif BITS_PER_LONG==32 && defined(CONFIG_LBDAF) && defined(CONFIG_PREEMPT)
 735        preempt_disable();
 736        part->nr_sects = size;
 737        preempt_enable();
 738#else
 739        part->nr_sects = size;
 740#endif
 741}
 742
 743#if defined(CONFIG_BLK_DEV_INTEGRITY)
 744extern void blk_integrity_add(struct gendisk *);
 745extern void blk_integrity_del(struct gendisk *);
 746#else   /* CONFIG_BLK_DEV_INTEGRITY */
 747static inline void blk_integrity_add(struct gendisk *disk) { }
 748static inline void blk_integrity_del(struct gendisk *disk) { }
 749#endif  /* CONFIG_BLK_DEV_INTEGRITY */
 750
 751#else /* CONFIG_BLOCK */
 752
 753static inline void printk_all_partitions(void) { }
 754
 755static inline dev_t blk_lookup_devt(const char *name, int partno)
 756{
 757        dev_t devt = MKDEV(0, 0);
 758        return devt;
 759}
 760#endif /* CONFIG_BLOCK */
 761
 762#endif /* _LINUX_GENHD_H */
 763