include/linux/genhd.h

   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
  28 extern struct device_type part_type;
  29 extern struct kobject *block_depr;
  30 extern struct class block_class;
  31
  32 enum {
  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
  72 struct 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
  85 struct 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
 101 struct partition_meta_info {
 102         char uuid[PARTITION_META_INFO_UUIDLTH];
 103         u8 volname[PARTITION_META_INFO_VOLNAMELTH];
 104 };
 105
 106 struct 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
 147 enum {
 148         DISK_EVENT_MEDIA_CHANGE                 = 1 << 0, /* media changed */
 149         DISK_EVENT_EJECT_REQUEST                = 1 << 1, /* eject requested */
 150 };
 151
 152 struct 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
 159 struct disk_events;
 160 struct badblocks;
 161
 162 #if defined(CONFIG_BLK_DEV_INTEGRITY)
 163
 164 struct 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
 174 struct 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
 216 static 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
 227 static 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
 234 static 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
 240 static inline dev_t disk_devt(struct gendisk *disk)
 241 {
 242         return MKDEV(disk->major, disk->first_minor);
 243 }
 244
 245 static inline dev_t part_devt(struct hd_struct *part)
 246 {
 247         return part_to_dev(part)->devt;
 248 }
 249
 250 extern struct hd_struct *__disk_get_part(struct gendisk *disk, int partno);
 251 extern struct hd_struct *disk_get_part(struct gendisk *disk, int partno);
 252
 253 static 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
 267 struct disk_part_iter {
 268         struct gendisk          *disk;
 269         struct hd_struct        *part;
 270         int                     idx;
 271         unsigned int            flags;
 272 };
 273
 274 extern void disk_part_iter_init(struct disk_part_iter *piter,
 275                                  struct gendisk *disk, unsigned int flags);
 276 extern struct hd_struct *disk_part_iter_next(struct disk_part_iter *piter);
 277 extern void disk_part_iter_exit(struct disk_part_iter *piter);
 278
 279 extern 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
 310 static 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
 319 static 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
 327 static 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
 341 static inline void part_stat_set_all(struct hd_struct *part, int value)
 342 {
 343         memset(&part->dkstats, value, sizeof(struct disk_stats));
 344 }
 345
 346 static inline int init_part_stats(struct hd_struct *part)
 347 {
 348         return 1;
 349 }
 350
 351 static 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
 379 void part_in_flight(struct request_queue *q, struct hd_struct *part,
 380                     unsigned int inflight[2]);
 381 void part_in_flight_rw(struct request_queue *q, struct hd_struct *part,
 382                        unsigned int inflight[2]);
 383 void part_dec_in_flight(struct request_queue *q, struct hd_struct *part,
 384                         int rw);
 385 void part_inc_in_flight(struct request_queue *q, struct hd_struct *part,
 386                         int rw);
 387
 388 static 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
 396 static inline void free_part_info(struct hd_struct *part)
 397 {
 398         kfree(part->info);
 399 }
 400
 401 /* block/blk-core.c */
 402 extern void part_round_stats(struct request_queue *q, int cpu, struct hd_struct *part);
 403
 404 /* block/genhd.c */
 405 extern void device_add_disk(struct device *parent, struct gendisk *disk,
 406                             const struct attribute_group **groups);
 407 static inline void add_disk(struct gendisk *disk)
 408 {
 409         device_add_disk(NULL, disk, NULL);
 410 }
 411 extern void device_add_disk_no_queue_reg(struct device *parent, struct gendisk *disk);
 412 static inline void add_disk_no_queue_reg(struct gendisk *disk)
 413 {
 414         device_add_disk_no_queue_reg(NULL, disk);
 415 }
 416
 417 extern void del_gendisk(struct gendisk *gp);
 418 extern struct gendisk *get_gendisk(dev_t dev, int *partno);
 419 extern struct block_device *bdget_disk(struct gendisk *disk, int partno);
 420
 421 extern void set_device_ro(struct block_device *bdev, int flag);
 422 extern void set_disk_ro(struct gendisk *disk, int flag);
 423
 424 static inline int get_disk_ro(struct gendisk *disk)
 425 {
 426         return disk->part0.policy;
 427 }
 428
 429 extern void disk_block_events(struct gendisk *disk);
 430 extern void disk_unblock_events(struct gendisk *disk);
 431 extern void disk_flush_events(struct gendisk *disk, unsigned int mask);
 432 extern unsigned int disk_clear_events(struct gendisk *disk, unsigned int mask);
 433
 434 /* drivers/char/random.c */
 435 extern void add_disk_randomness(struct gendisk *disk) __latent_entropy;
 436 extern void rand_initialize_disk(struct gendisk *disk);
 437
 438 static inline sector_t get_start_sect(struct block_device *bdev)
 439 {
 440         return bdev->bd_part->start_sect;
 441 }
 442 static inline sector_t get_capacity(struct gendisk *disk)
 443 {
 444         return disk->part0.nr_sects;
 445 }
 446 static inline void set_capacity(struct gendisk *disk, sector_t size)
 447 {
 448         disk->part0.nr_sects = size;
 449 }
 450
 451 #ifdef CONFIG_SOLARIS_X86_PARTITION
 452
 453 #define SOLARIS_X86_NUMSLICE    16
 454 #define SOLARIS_X86_VTOC_SANE   (0x600DDEEEUL)
 455
 456 struct solaris_x86_slice {
 457         __le16 s_tag;           /* ID tag of partition */
 458         __le16 s_flag;          /* permission flags */
 459         __le32 s_start;         /* start sector no of partition */
 460         __le32 s_size;          /* # of blocks in partition */
 461 };
 462
 463 struct solaris_x86_vtoc {
 464         unsigned int v_bootinfo[3];     /* info needed by mboot (unsupported) */
 465         __le32 v_sanity;                /* to verify vtoc sanity */
 466         __le32 v_version;               /* layout version */
 467         char    v_volume[8];            /* volume name */
 468         __le16  v_sectorsz;             /* sector size in bytes */
 469         __le16  v_nparts;               /* number of partitions */
 470         unsigned int v_reserved[10];    /* free space */
 471         struct solaris_x86_slice
 472                 v_slice[SOLARIS_X86_NUMSLICE]; /* slice headers */
 473         unsigned int timestamp[SOLARIS_X86_NUMSLICE]; /* timestamp (unsupported) */
 474         char    v_asciilabel[128];      /* for compatibility */
 475 };
 476
 477 #endif /* CONFIG_SOLARIS_X86_PARTITION */
 478
 479 #ifdef CONFIG_BSD_DISKLABEL
 480 /*
 481  * BSD disklabel support by Yossi Gottlieb <yogo@math.tau.ac.il>
 482  * updated by Marc Espie <Marc.Espie@openbsd.org>
 483  */
 484
 485 /* check against BSD src/sys/sys/disklabel.h for consistency */
 486
 487 #define BSD_DISKMAGIC   (0x82564557UL)  /* The disk magic number */
 488 #define BSD_MAXPARTITIONS       16
 489 #define OPENBSD_MAXPARTITIONS   16
 490 #define BSD_FS_UNUSED           0       /* disklabel unused partition entry ID */
 491 struct bsd_disklabel {
 492         __le32  d_magic;                /* the magic number */
 493         __s16   d_type;                 /* drive type */
 494         __s16   d_subtype;              /* controller/d_type specific */
 495         char    d_typename[16];         /* type name, e.g. "eagle" */
 496         char    d_packname[16];                 /* pack identifier */
 497         __u32   d_secsize;              /* # of bytes per sector */
 498         __u32   d_nsectors;             /* # of data sectors per track */
 499         __u32   d_ntracks;              /* # of tracks per cylinder */
 500         __u32   d_ncylinders;           /* # of data cylinders per unit */
 501         __u32   d_secpercyl;            /* # of data sectors per cylinder */
 502         __u32   d_secperunit;           /* # of data sectors per unit */
 503         __u16   d_sparespertrack;       /* # of spare sectors per track */
 504         __u16   d_sparespercyl;         /* # of spare sectors per cylinder */
 505         __u32   d_acylinders;           /* # of alt. cylinders per unit */
 506         __u16   d_rpm;                  /* rotational speed */
 507         __u16   d_interleave;           /* hardware sector interleave */
 508         __u16   d_trackskew;            /* sector 0 skew, per track */
 509         __u16   d_cylskew;              /* sector 0 skew, per cylinder */
 510         __u32   d_headswitch;           /* head switch time, usec */
 511         __u32   d_trkseek;              /* track-to-track seek, usec */
 512         __u32   d_flags;                /* generic flags */
 513 #define NDDATA 5
 514         __u32   d_drivedata[NDDATA];    /* drive-type specific information */
 515 #define NSPARE 5
 516         __u32   d_spare[NSPARE];        /* reserved for future use */
 517         __le32  d_magic2;               /* the magic number (again) */
 518         __le16  d_checksum;             /* xor of data incl. partitions */
 519
 520                         /* filesystem and partition information: */
 521         __le16  d_npartitions;          /* number of partitions in following */
 522         __le32  d_bbsize;               /* size of boot area at sn0, bytes */
 523         __le32  d_sbsize;               /* max size of fs superblock, bytes */
 524         struct  bsd_partition {         /* the partition table */
 525                 __le32  p_size;         /* number of sectors in partition */
 526                 __le32  p_offset;       /* starting sector */
 527                 __le32  p_fsize;        /* filesystem basic fragment size */
 528                 __u8    p_fstype;       /* filesystem type, see below */
 529                 __u8    p_frag;         /* filesystem fragments per block */
 530                 __le16  p_cpg;          /* filesystem cylinders per group */
 531         } d_partitions[BSD_MAXPARTITIONS];      /* actually may be more */
 532 };
 533
 534 #endif  /* CONFIG_BSD_DISKLABEL */
 535
 536 #ifdef CONFIG_UNIXWARE_DISKLABEL
 537 /*
 538  * Unixware slices support by Andrzej Krzysztofowicz <ankry@mif.pg.gda.pl>
 539  * and Krzysztof G. Baranowski <kgb@knm.org.pl>
 540  */
 541
 542 #define UNIXWARE_DISKMAGIC     (0xCA5E600DUL)   /* The disk magic number */
 543 #define UNIXWARE_DISKMAGIC2    (0x600DDEEEUL)   /* The slice table magic nr */
 544 #define UNIXWARE_NUMSLICE      16
 545 #define UNIXWARE_FS_UNUSED     0                /* Unused slice entry ID */
 546
 547 struct unixware_slice {
 548         __le16   s_label;       /* label */
 549         __le16   s_flags;       /* permission flags */
 550         __le32   start_sect;    /* starting sector */
 551         __le32   nr_sects;      /* number of sectors in slice */
 552 };
 553
 554 struct unixware_disklabel {
 555         __le32   d_type;                /* drive type */
 556         __le32   d_magic;                /* the magic number */
 557         __le32   d_version;              /* version number */
 558         char    d_serial[12];           /* serial number of the device */
 559         __le32   d_ncylinders;           /* # of data cylinders per device */
 560         __le32   d_ntracks;              /* # of tracks per cylinder */
 561         __le32   d_nsectors;             /* # of data sectors per track */
 562         __le32   d_secsize;              /* # of bytes per sector */
 563         __le32   d_part_start;           /* # of first sector of this partition */
 564         __le32   d_unknown1[12];         /* ? */
 565         __le32  d_alt_tbl;              /* byte offset of alternate table */
 566         __le32  d_alt_len;              /* byte length of alternate table */
 567         __le32  d_phys_cyl;             /* # of physical cylinders per device */
 568         __le32  d_phys_trk;             /* # of physical tracks per cylinder */
 569         __le32  d_phys_sec;             /* # of physical sectors per track */
 570         __le32  d_phys_bytes;           /* # of physical bytes per sector */
 571         __le32  d_unknown2;             /* ? */
 572         __le32   d_unknown3;             /* ? */
 573         __le32  d_pad[8];               /* pad */
 574
 575         struct unixware_vtoc {
 576                 __le32  v_magic;                /* the magic number */
 577                 __le32  v_version;              /* version number */
 578                 char    v_name[8];              /* volume name */
 579                 __le16  v_nslices;              /* # of slices */
 580                 __le16  v_unknown1;             /* ? */
 581                 __le32  v_reserved[10];         /* reserved */
 582                 struct unixware_slice
 583                         v_slice[UNIXWARE_NUMSLICE];     /* slice headers */
 584         } vtoc;
 585
 586 };  /* 408 */
 587
 588 #endif /* CONFIG_UNIXWARE_DISKLABEL */
 589
 590 #ifdef CONFIG_MINIX_SUBPARTITION
 591 #   define MINIX_NR_SUBPARTITIONS  4
 592 #endif /* CONFIG_MINIX_SUBPARTITION */
 593
 594 #define ADDPART_FLAG_NONE       0
 595 #define ADDPART_FLAG_RAID       1
 596 #define ADDPART_FLAG_WHOLEDISK  2
 597
 598 extern int blk_alloc_devt(struct hd_struct *part, dev_t *devt);
 599 extern void blk_free_devt(dev_t devt);
 600 extern dev_t blk_lookup_devt(const char *name, int partno);
 601 extern char *disk_name (struct gendisk *hd, int partno, char *buf);
 602
 603 extern int disk_expand_part_tbl(struct gendisk *disk, int target);
 604 extern int rescan_partitions(struct gendisk *disk, struct block_device *bdev);
 605 extern int invalidate_partitions(struct gendisk *disk, struct block_device *bdev);
 606 extern struct hd_struct * __must_check add_partition(struct gendisk *disk,
 607                                                      int partno, sector_t start,
 608                                                      sector_t len, int flags,
 609                                                      struct partition_meta_info
 610                                                        *info);
 611 extern void __delete_partition(struct percpu_ref *);
 612 extern void delete_partition(struct gendisk *, int);
 613 extern void printk_all_partitions(void);
 614
 615 extern struct gendisk *__alloc_disk_node(int minors, int node_id);
 616 extern struct kobject *get_disk_and_module(struct gendisk *disk);
 617 extern void put_disk(struct gendisk *disk);
 618 extern void put_disk_and_module(struct gendisk *disk);
 619 extern void blk_register_region(dev_t devt, unsigned long range,
 620                         struct module *module,
 621                         struct kobject *(*probe)(dev_t, int *, void *),
 622                         int (*lock)(dev_t, void *),
 623                         void *data);
 624 extern void blk_unregister_region(dev_t devt, unsigned long range);
 625
 626 extern ssize_t part_size_show(struct device *dev,
 627                               struct device_attribute *attr, char *buf);
 628 extern ssize_t part_stat_show(struct device *dev,
 629                               struct device_attribute *attr, char *buf);
 630 extern ssize_t part_inflight_show(struct device *dev,
 631                               struct device_attribute *attr, char *buf);
 632 #ifdef CONFIG_FAIL_MAKE_REQUEST
 633 extern ssize_t part_fail_show(struct device *dev,
 634                               struct device_attribute *attr, char *buf);
 635 extern ssize_t part_fail_store(struct device *dev,
 636                                struct device_attribute *attr,
 637                                const char *buf, size_t count);
 638 #endif /* CONFIG_FAIL_MAKE_REQUEST */
 639
 640 #define alloc_disk_node(minors, node_id)                                \
 641 ({                                                                      \
 642         static struct lock_class_key __key;                             \
 643         const char *__name;                                             \
 644         struct gendisk *__disk;                                         \
 645                                                                         \
 646         __name = "(gendisk_completion)"#minors"("#node_id")";           \
 647                                                                         \
 648         __disk = __alloc_disk_node(minors, node_id);                    \
 649                                                                         \
 650         if (__disk)                                                     \
 651                 lockdep_init_map(&__disk->lockdep_map, __name, &__key, 0); \
 652                                                                         \
 653         __disk;                                                         \
 654 })
 655
 656 #define alloc_disk(minors) alloc_disk_node(minors, NUMA_NO_NODE)
 657
 658 static inline int hd_ref_init(struct hd_struct *part)
 659 {
 660         if (percpu_ref_init(&part->ref, __delete_partition, 0,
 661                                 GFP_KERNEL))
 662                 return -ENOMEM;
 663         return 0;
 664 }
 665
 666 static inline void hd_struct_get(struct hd_struct *part)
 667 {
 668         percpu_ref_get(&part->ref);
 669 }
 670
 671 static inline int hd_struct_try_get(struct hd_struct *part)
 672 {
 673         return percpu_ref_tryget_live(&part->ref);
 674 }
 675
 676 static inline void hd_struct_put(struct hd_struct *part)
 677 {
 678         percpu_ref_put(&part->ref);
 679 }
 680
 681 static inline void hd_struct_kill(struct hd_struct *part)
 682 {
 683         percpu_ref_kill(&part->ref);
 684 }
 685
 686 static inline void hd_free_part(struct hd_struct *part)
 687 {
 688         free_part_stats(part);
 689         free_part_info(part);
 690         percpu_ref_exit(&part->ref);
 691 }
 692
 693 /*
 694  * Any access of part->nr_sects which is not protected by partition
 695  * bd_mutex or gendisk bdev bd_mutex, should be done using this
 696  * accessor function.
 697  *
 698  * Code written along the lines of i_size_read() and i_size_write().
 699  * CONFIG_PREEMPT case optimizes the case of UP kernel with preemption
 700  * on.
 701  */
 702 static inline sector_t part_nr_sects_read(struct hd_struct *part)
 703 {
 704 #if BITS_PER_LONG==32 && defined(CONFIG_LBDAF) && defined(CONFIG_SMP)
 705         sector_t nr_sects;
 706         unsigned seq;
 707         do {
 708                 seq = read_seqcount_begin(&part->nr_sects_seq);
 709                 nr_sects = part->nr_sects;
 710         } while (read_seqcount_retry(&part->nr_sects_seq, seq));
 711         return nr_sects;
 712 #elif BITS_PER_LONG==32 && defined(CONFIG_LBDAF) && defined(CONFIG_PREEMPT)
 713         sector_t nr_sects;
 714
 715         preempt_disable();
 716         nr_sects = part->nr_sects;
 717         preempt_enable();
 718         return nr_sects;
 719 #else
 720         return part->nr_sects;
 721 #endif
 722 }
 723
 724 /*
 725  * Should be called with mutex lock held (typically bd_mutex) of partition
 726  * to provide mutual exlusion among writers otherwise seqcount might be
 727  * left in wrong state leaving the readers spinning infinitely.
 728  */
 729 static inline void part_nr_sects_write(struct hd_struct *part, sector_t size)
 730 {
 731 #if BITS_PER_LONG==32 && defined(CONFIG_LBDAF) && defined(CONFIG_SMP)
 732         write_seqcount_begin(&part->nr_sects_seq);
 733         part->nr_sects = size;
 734         write_seqcount_end(&part->nr_sects_seq);
 735 #elif BITS_PER_LONG==32 && defined(CONFIG_LBDAF) && defined(CONFIG_PREEMPT)
 736         preempt_disable();
 737         part->nr_sects = size;
 738         preempt_enable();
 739 #else
 740         part->nr_sects = size;
 741 #endif
 742 }
 743
 744 #if defined(CONFIG_BLK_DEV_INTEGRITY)
 745 extern void blk_integrity_add(struct gendisk *);
 746 extern void blk_integrity_del(struct gendisk *);
 747 #else   /* CONFIG_BLK_DEV_INTEGRITY */
 748 static inline void blk_integrity_add(struct gendisk *disk) { }
 749 static inline void blk_integrity_del(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 #endif /* CONFIG_BLOCK */
 762
 763 #endif /* _LINUX_GENHD_H */