include/linux/genhd.h

   1 #ifndef _LINUX_GENHD_H
   2 #define _LINUX_GENHD_H
   3
   4 /*
   5  *      genhd.h Copyright (C) 1992 Drew Eckhardt
   6  *      Generic hard disk header file by
   7  *              Drew Eckhardt
   8  *
   9  *              <drew@colorado.edu>
  10  */
  11
  12 #include <linux/types.h>
  13 #include <linux/kdev_t.h>
  14 #include <linux/rcupdate.h>
  15 #include <linux/slab.h>
  16 #include <linux/percpu-refcount.h>
  17
  18 #ifdef CONFIG_BLOCK
  19
  20 #define dev_to_disk(device)     container_of((device), struct gendisk, part0.__dev)
  21 #define dev_to_part(device)     container_of((device), struct hd_struct, __dev)
  22 #define disk_to_dev(disk)       (&(disk)->part0.__dev)
  23 #define part_to_dev(part)       (&((part)->__dev))
  24
  25 extern struct device_type part_type;
  26 extern struct kobject *block_depr;
  27 extern struct class block_class;
  28
  29 enum {
  30 /* These three have identical behaviour; use the second one if DOS FDISK gets
  31    confused about extended/logical partitions starting past cylinder 1023. */
  32         DOS_EXTENDED_PARTITION = 5,
  33         LINUX_EXTENDED_PARTITION = 0x85,
  34         WIN98_EXTENDED_PARTITION = 0x0f,
  35
  36         SUN_WHOLE_DISK = DOS_EXTENDED_PARTITION,
  37
  38         LINUX_SWAP_PARTITION = 0x82,
  39         LINUX_DATA_PARTITION = 0x83,
  40         LINUX_LVM_PARTITION = 0x8e,
  41         LINUX_RAID_PARTITION = 0xfd,    /* autodetect RAID partition */
  42
  43         SOLARIS_X86_PARTITION = LINUX_SWAP_PARTITION,
  44         NEW_SOLARIS_X86_PARTITION = 0xbf,
  45
  46         DM6_AUX1PARTITION = 0x51,       /* no DDO:  use xlated geom */
  47         DM6_AUX3PARTITION = 0x53,       /* no DDO:  use xlated geom */
  48         DM6_PARTITION = 0x54,           /* has DDO: use xlated geom & offset */
  49         EZD_PARTITION = 0x55,           /* EZ-DRIVE */
  50
  51         FREEBSD_PARTITION = 0xa5,       /* FreeBSD Partition ID */
  52         OPENBSD_PARTITION = 0xa6,       /* OpenBSD Partition ID */
  53         NETBSD_PARTITION = 0xa9,        /* NetBSD Partition ID */
  54         BSDI_PARTITION = 0xb7,          /* BSDI Partition ID */
  55         MINIX_PARTITION = 0x81,         /* Minix Partition ID */
  56         UNIXWARE_PARTITION = 0x63,      /* Same as GNU_HURD and SCO Unix */
  57 };
  58
  59 #define DISK_MAX_PARTS                  256
  60 #define DISK_NAME_LEN                   32
  61
  62 #include <linux/major.h>
  63 #include <linux/device.h>
  64 #include <linux/smp.h>
  65 #include <linux/string.h>
  66 #include <linux/fs.h>
  67 #include <linux/workqueue.h>
  68
  69 struct partition {
  70         unsigned char boot_ind;         /* 0x80 - active */
  71         unsigned char head;             /* starting head */
  72         unsigned char sector;           /* starting sector */
  73         unsigned char cyl;              /* starting cylinder */
  74         unsigned char sys_ind;          /* What partition type */
  75         unsigned char end_head;         /* end head */
  76         unsigned char end_sector;       /* end sector */
  77         unsigned char end_cyl;          /* end cylinder */
  78         __le32 start_sect;      /* starting sector counting from 0 */
  79         __le32 nr_sects;                /* nr of sectors in partition */
  80 } __attribute__((packed));
  81
  82 struct disk_stats {
  83         unsigned long sectors[2];       /* READs and WRITEs */
  84         unsigned long ios[2];
  85         unsigned long merges[2];
  86         unsigned long ticks[2];
  87         unsigned long io_ticks;
  88         unsigned long time_in_queue;
  89 };
  90
  91 #define PARTITION_META_INFO_VOLNAMELTH  64
  92 /*
  93  * Enough for the string representation of any kind of UUID plus NULL.
  94  * EFI UUID is 36 characters. MSDOS UUID is 11 characters.
  95  */
  96 #define PARTITION_META_INFO_UUIDLTH     37
  97
  98 struct partition_meta_info {
  99         char uuid[PARTITION_META_INFO_UUIDLTH];
 100         u8 volname[PARTITION_META_INFO_VOLNAMELTH];
 101 };
 102
 103 struct hd_struct {
 104         sector_t start_sect;
 105         /*
 106          * nr_sects is protected by sequence counter. One might extend a
 107          * partition while IO is happening to it and update of nr_sects
 108          * can be non-atomic on 32bit machines with 64bit sector_t.
 109          */
 110         sector_t nr_sects;
 111         seqcount_t nr_sects_seq;
 112         sector_t alignment_offset;
 113         unsigned int discard_alignment;
 114         struct device __dev;
 115         struct kobject *holder_dir;
 116         int policy, partno;
 117         struct partition_meta_info *info;
 118 #ifdef CONFIG_FAIL_MAKE_REQUEST
 119         int make_it_fail;
 120 #endif
 121         unsigned long stamp;
 122         atomic_t in_flight[2];
 123 #ifdef  CONFIG_SMP
 124         struct disk_stats __percpu *dkstats;
 125 #else
 126         struct disk_stats dkstats;
 127 #endif
 128         struct percpu_ref ref;
 129         struct rcu_head rcu_head;
 130 };
 131
 132 #define GENHD_FL_REMOVABLE                      1
 133 /* 2 is unused */
 134 #define GENHD_FL_MEDIA_CHANGE_NOTIFY            4
 135 #define GENHD_FL_CD                             8
 136 #define GENHD_FL_UP                             16
 137 #define GENHD_FL_SUPPRESS_PARTITION_INFO        32
 138 #define GENHD_FL_EXT_DEVT                       64 /* allow extended devt */
 139 #define GENHD_FL_NATIVE_CAPACITY                128
 140 #define GENHD_FL_BLOCK_EVENTS_ON_EXCL_WRITE     256
 141 #define GENHD_FL_NO_PART_SCAN                   512
 142
 143 enum {
 144         DISK_EVENT_MEDIA_CHANGE                 = 1 << 0, /* media changed */
 145         DISK_EVENT_EJECT_REQUEST                = 1 << 1, /* eject requested */
 146 };
 147
 148 #define BLK_SCSI_MAX_CMDS       (256)
 149 #define BLK_SCSI_CMD_PER_LONG   (BLK_SCSI_MAX_CMDS / (sizeof(long) * 8))
 150
 151 struct blk_scsi_cmd_filter {
 152         unsigned long read_ok[BLK_SCSI_CMD_PER_LONG];
 153         unsigned long write_ok[BLK_SCSI_CMD_PER_LONG];
 154         struct kobject kobj;
 155 };
 156
 157 struct disk_part_tbl {
 158         struct rcu_head rcu_head;
 159         int len;
 160         struct hd_struct __rcu *last_lookup;
 161         struct hd_struct __rcu *part[];
 162 };
 163
 164 struct disk_events;
 165 struct badblocks;
 166
 167 #if defined(CONFIG_BLK_DEV_INTEGRITY)
 168
 169 struct blk_integrity {
 170         struct blk_integrity_profile    *profile;
 171         unsigned char                   flags;
 172         unsigned char                   tuple_size;
 173         unsigned char                   interval_exp;
 174         unsigned char                   tag_size;
 175 };
 176
 177 #endif  /* CONFIG_BLK_DEV_INTEGRITY */
 178
 179 struct gendisk {
 180         /* major, first_minor and minors are input parameters only,
 181          * don't use directly.  Use disk_devt() and disk_max_parts().
 182          */
 183         int major;                      /* major number of driver */
 184         int first_minor;
 185         int minors;                     /* maximum number of minors, =1 for
 186                                          * disks that can't be partitioned. */
 187
 188         char disk_name[DISK_NAME_LEN];  /* name of major driver */
 189         char *(*devnode)(struct gendisk *gd, umode_t *mode);
 190
 191         unsigned int events;            /* supported events */
 192         unsigned int async_events;      /* async events, subset of all */
 193
 194         /* Array of pointers to partitions indexed by partno.
 195          * Protected with matching bdev lock but stat and other
 196          * non-critical accesses use RCU.  Always access through
 197          * helpers.
 198          */
 199         struct disk_part_tbl __rcu *part_tbl;
 200         struct hd_struct part0;
 201
 202         const struct block_device_operations *fops;
 203         struct request_queue *queue;
 204         void *private_data;
 205
 206         int flags;
 207         struct device *driverfs_dev;  // FIXME: remove
 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
 220 static 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
 231 static inline void part_pack_uuid(const u8 *uuid_str, u8 *to)
 232 {
 233         int i;
 234         for (i = 0; i < 16; ++i) {
 235                 *to++ = (hex_to_bin(*uuid_str) << 4) |
 236                         (hex_to_bin(*(uuid_str + 1)));
 237                 uuid_str += 2;
 238                 switch (i) {
 239                 case 3:
 240                 case 5:
 241                 case 7:
 242                 case 9:
 243                         uuid_str++;
 244                         continue;
 245                 }
 246         }
 247 }
 248
 249 static inline int blk_part_pack_uuid(const u8 *uuid_str, u8 *to)
 250 {
 251         part_pack_uuid(uuid_str, to);
 252         return 0;
 253 }
 254
 255 static inline int disk_max_parts(struct gendisk *disk)
 256 {
 257         if (disk->flags & GENHD_FL_EXT_DEVT)
 258                 return DISK_MAX_PARTS;
 259         return disk->minors;
 260 }
 261
 262 static inline bool disk_part_scan_enabled(struct gendisk *disk)
 263 {
 264         return disk_max_parts(disk) > 1 &&
 265                 !(disk->flags & GENHD_FL_NO_PART_SCAN);
 266 }
 267
 268 static inline dev_t disk_devt(struct gendisk *disk)
 269 {
 270         return disk_to_dev(disk)->devt;
 271 }
 272
 273 static inline dev_t part_devt(struct hd_struct *part)
 274 {
 275         return part_to_dev(part)->devt;
 276 }
 277
 278 extern struct hd_struct *disk_get_part(struct gendisk *disk, int partno);
 279
 280 static inline void disk_put_part(struct hd_struct *part)
 281 {
 282         if (likely(part))
 283                 put_device(part_to_dev(part));
 284 }
 285
 286 /*
 287  * Smarter partition iterator without context limits.
 288  */
 289 #define DISK_PITER_REVERSE      (1 << 0) /* iterate in the reverse direction */
 290 #define DISK_PITER_INCL_EMPTY   (1 << 1) /* include 0-sized parts */
 291 #define DISK_PITER_INCL_PART0   (1 << 2) /* include partition 0 */
 292 #define DISK_PITER_INCL_EMPTY_PART0 (1 << 3) /* include empty partition 0 */
 293
 294 struct disk_part_iter {
 295         struct gendisk          *disk;
 296         struct hd_struct        *part;
 297         int                     idx;
 298         unsigned int            flags;
 299 };
 300
 301 extern void disk_part_iter_init(struct disk_part_iter *piter,
 302                                  struct gendisk *disk, unsigned int flags);
 303 extern struct hd_struct *disk_part_iter_next(struct disk_part_iter *piter);
 304 extern void disk_part_iter_exit(struct disk_part_iter *piter);
 305
 306 extern struct hd_struct *disk_map_sector_rcu(struct gendisk *disk,
 307                                              sector_t sector);
 308
 309 /*
 310  * Macros to operate on percpu disk statistics:
 311  *
 312  * {disk|part|all}_stat_{add|sub|inc|dec}() modify the stat counters
 313  * and should be called between disk_stat_lock() and
 314  * disk_stat_unlock().
 315  *
 316  * part_stat_read() can be called at any time.
 317  *
 318  * part_stat_{add|set_all}() and {init|free}_part_stats are for
 319  * internal use only.
 320  */
 321 #ifdef  CONFIG_SMP
 322 #define part_stat_lock()        ({ rcu_read_lock(); get_cpu(); })
 323 #define part_stat_unlock()      do { put_cpu(); rcu_read_unlock(); } while (0)
 324
 325 #define __part_stat_add(cpu, part, field, addnd)                        \
 326         (per_cpu_ptr((part)->dkstats, (cpu))->field += (addnd))
 327
 328 #define part_stat_read(part, field)                                     \
 329 ({                                                                      \
 330         typeof((part)->dkstats->field) res = 0;                         \
 331         unsigned int _cpu;                                              \
 332         for_each_possible_cpu(_cpu)                                     \
 333                 res += per_cpu_ptr((part)->dkstats, _cpu)->field;       \
 334         res;                                                            \
 335 })
 336
 337 static inline void part_stat_set_all(struct hd_struct *part, int value)
 338 {
 339         int i;
 340
 341         for_each_possible_cpu(i)
 342                 memset(per_cpu_ptr(part->dkstats, i), value,
 343                                 sizeof(struct disk_stats));
 344 }
 345
 346 static inline int init_part_stats(struct hd_struct *part)
 347 {
 348         part->dkstats = alloc_percpu(struct disk_stats);
 349         if (!part->dkstats)
 350                 return 0;
 351         return 1;
 352 }
 353
 354 static inline void free_part_stats(struct hd_struct *part)
 355 {
 356         free_percpu(part->dkstats);
 357 }
 358
 359 #else /* !CONFIG_SMP */
 360 #define part_stat_lock()        ({ rcu_read_lock(); 0; })
 361 #define part_stat_unlock()      rcu_read_unlock()
 362
 363 #define __part_stat_add(cpu, part, field, addnd)                                \
 364         ((part)->dkstats.field += addnd)
 365
 366 #define part_stat_read(part, field)     ((part)->dkstats.field)
 367
 368 static inline void part_stat_set_all(struct hd_struct *part, int value)
 369 {
 370         memset(&part->dkstats, value, sizeof(struct disk_stats));
 371 }
 372
 373 static inline int init_part_stats(struct hd_struct *part)
 374 {
 375         return 1;
 376 }
 377
 378 static inline void free_part_stats(struct hd_struct *part)
 379 {
 380 }
 381
 382 #endif /* CONFIG_SMP */
 383
 384 #define part_stat_add(cpu, part, field, addnd)  do {                    \
 385         __part_stat_add((cpu), (part), field, addnd);                   \
 386         if ((part)->partno)                                             \
 387                 __part_stat_add((cpu), &part_to_disk((part))->part0,    \
 388                                 field, addnd);                          \
 389 } while (0)
 390
 391 #define part_stat_dec(cpu, gendiskp, field)                             \
 392         part_stat_add(cpu, gendiskp, field, -1)
 393 #define part_stat_inc(cpu, gendiskp, field)                             \
 394         part_stat_add(cpu, gendiskp, field, 1)
 395 #define part_stat_sub(cpu, gendiskp, field, subnd)                      \
 396         part_stat_add(cpu, gendiskp, field, -subnd)
 397
 398 static inline void part_inc_in_flight(struct hd_struct *part, int rw)
 399 {
 400         atomic_inc(&part->in_flight[rw]);
 401         if (part->partno)
 402                 atomic_inc(&part_to_disk(part)->part0.in_flight[rw]);
 403 }
 404
 405 static inline void part_dec_in_flight(struct hd_struct *part, int rw)
 406 {
 407         atomic_dec(&part->in_flight[rw]);
 408         if (part->partno)
 409                 atomic_dec(&part_to_disk(part)->part0.in_flight[rw]);
 410 }
 411
 412 static inline int part_in_flight(struct hd_struct *part)
 413 {
 414         return atomic_read(&part->in_flight[0]) + atomic_read(&part->in_flight[1]);
 415 }
 416
 417 static inline struct partition_meta_info *alloc_part_info(struct gendisk *disk)
 418 {
 419         if (disk)
 420                 return kzalloc_node(sizeof(struct partition_meta_info),
 421                                     GFP_KERNEL, disk->node_id);
 422         return kzalloc(sizeof(struct partition_meta_info), GFP_KERNEL);
 423 }
 424
 425 static inline void free_part_info(struct hd_struct *part)
 426 {
 427         kfree(part->info);
 428 }
 429
 430 /* block/blk-core.c */
 431 extern void part_round_stats(int cpu, struct hd_struct *part);
 432
 433 /* block/genhd.c */
 434 extern void add_disk(struct gendisk *disk);
 435 extern void del_gendisk(struct gendisk *gp);
 436 extern struct gendisk *get_gendisk(dev_t dev, int *partno);
 437 extern struct block_device *bdget_disk(struct gendisk *disk, int partno);
 438
 439 extern void set_device_ro(struct block_device *bdev, int flag);
 440 extern void set_disk_ro(struct gendisk *disk, int flag);
 441
 442 static inline int get_disk_ro(struct gendisk *disk)
 443 {
 444         return disk->part0.policy;
 445 }
 446
 447 extern void disk_block_events(struct gendisk *disk);
 448 extern void disk_unblock_events(struct gendisk *disk);
 449 extern void disk_flush_events(struct gendisk *disk, unsigned int mask);
 450 extern unsigned int disk_clear_events(struct gendisk *disk, unsigned int mask);
 451
 452 /* drivers/char/random.c */
 453 extern void add_disk_randomness(struct gendisk *disk);
 454 extern void rand_initialize_disk(struct gendisk *disk);
 455
 456 static inline sector_t get_start_sect(struct block_device *bdev)
 457 {
 458         return bdev->bd_part->start_sect;
 459 }
 460 static inline sector_t get_capacity(struct gendisk *disk)
 461 {
 462         return disk->part0.nr_sects;
 463 }
 464 static inline void set_capacity(struct gendisk *disk, sector_t size)
 465 {
 466         disk->part0.nr_sects = size;
 467 }
 468
 469 #ifdef CONFIG_SOLARIS_X86_PARTITION
 470
 471 #define SOLARIS_X86_NUMSLICE    16
 472 #define SOLARIS_X86_VTOC_SANE   (0x600DDEEEUL)
 473
 474 struct solaris_x86_slice {
 475         __le16 s_tag;           /* ID tag of partition */
 476         __le16 s_flag;          /* permission flags */
 477         __le32 s_start;         /* start sector no of partition */
 478         __le32 s_size;          /* # of blocks in partition */
 479 };
 480
 481 struct solaris_x86_vtoc {
 482         unsigned int v_bootinfo[3];     /* info needed by mboot (unsupported) */
 483         __le32 v_sanity;                /* to verify vtoc sanity */
 484         __le32 v_version;               /* layout version */
 485         char    v_volume[8];            /* volume name */
 486         __le16  v_sectorsz;             /* sector size in bytes */
 487         __le16  v_nparts;               /* number of partitions */
 488         unsigned int v_reserved[10];    /* free space */
 489         struct solaris_x86_slice
 490                 v_slice[SOLARIS_X86_NUMSLICE]; /* slice headers */
 491         unsigned int timestamp[SOLARIS_X86_NUMSLICE]; /* timestamp (unsupported) */
 492         char    v_asciilabel[128];      /* for compatibility */
 493 };
 494
 495 #endif /* CONFIG_SOLARIS_X86_PARTITION */
 496
 497 #ifdef CONFIG_BSD_DISKLABEL
 498 /*
 499  * BSD disklabel support by Yossi Gottlieb <yogo@math.tau.ac.il>
 500  * updated by Marc Espie <Marc.Espie@openbsd.org>
 501  */
 502
 503 /* check against BSD src/sys/sys/disklabel.h for consistency */
 504
 505 #define BSD_DISKMAGIC   (0x82564557UL)  /* The disk magic number */
 506 #define BSD_MAXPARTITIONS       16
 507 #define OPENBSD_MAXPARTITIONS   16
 508 #define BSD_FS_UNUSED           0       /* disklabel unused partition entry ID */
 509 struct bsd_disklabel {
 510         __le32  d_magic;                /* the magic number */
 511         __s16   d_type;                 /* drive type */
 512         __s16   d_subtype;              /* controller/d_type specific */
 513         char    d_typename[16];         /* type name, e.g. "eagle" */
 514         char    d_packname[16];                 /* pack identifier */
 515         __u32   d_secsize;              /* # of bytes per sector */
 516         __u32   d_nsectors;             /* # of data sectors per track */
 517         __u32   d_ntracks;              /* # of tracks per cylinder */
 518         __u32   d_ncylinders;           /* # of data cylinders per unit */
 519         __u32   d_secpercyl;            /* # of data sectors per cylinder */
 520         __u32   d_secperunit;           /* # of data sectors per unit */
 521         __u16   d_sparespertrack;       /* # of spare sectors per track */
 522         __u16   d_sparespercyl;         /* # of spare sectors per cylinder */
 523         __u32   d_acylinders;           /* # of alt. cylinders per unit */
 524         __u16   d_rpm;                  /* rotational speed */
 525         __u16   d_interleave;           /* hardware sector interleave */
 526         __u16   d_trackskew;            /* sector 0 skew, per track */
 527         __u16   d_cylskew;              /* sector 0 skew, per cylinder */
 528         __u32   d_headswitch;           /* head switch time, usec */
 529         __u32   d_trkseek;              /* track-to-track seek, usec */
 530         __u32   d_flags;                /* generic flags */
 531 #define NDDATA 5
 532         __u32   d_drivedata[NDDATA];    /* drive-type specific information */
 533 #define NSPARE 5
 534         __u32   d_spare[NSPARE];        /* reserved for future use */
 535         __le32  d_magic2;               /* the magic number (again) */
 536         __le16  d_checksum;             /* xor of data incl. partitions */
 537
 538                         /* filesystem and partition information: */
 539         __le16  d_npartitions;          /* number of partitions in following */
 540         __le32  d_bbsize;               /* size of boot area at sn0, bytes */
 541         __le32  d_sbsize;               /* max size of fs superblock, bytes */
 542         struct  bsd_partition {         /* the partition table */
 543                 __le32  p_size;         /* number of sectors in partition */
 544                 __le32  p_offset;       /* starting sector */
 545                 __le32  p_fsize;        /* filesystem basic fragment size */
 546                 __u8    p_fstype;       /* filesystem type, see below */
 547                 __u8    p_frag;         /* filesystem fragments per block */
 548                 __le16  p_cpg;          /* filesystem cylinders per group */
 549         } d_partitions[BSD_MAXPARTITIONS];      /* actually may be more */
 550 };
 551
 552 #endif  /* CONFIG_BSD_DISKLABEL */
 553
 554 #ifdef CONFIG_UNIXWARE_DISKLABEL
 555 /*
 556  * Unixware slices support by Andrzej Krzysztofowicz <ankry@mif.pg.gda.pl>
 557  * and Krzysztof G. Baranowski <kgb@knm.org.pl>
 558  */
 559
 560 #define UNIXWARE_DISKMAGIC     (0xCA5E600DUL)   /* The disk magic number */
 561 #define UNIXWARE_DISKMAGIC2    (0x600DDEEEUL)   /* The slice table magic nr */
 562 #define UNIXWARE_NUMSLICE      16
 563 #define UNIXWARE_FS_UNUSED     0                /* Unused slice entry ID */
 564
 565 struct unixware_slice {
 566         __le16   s_label;       /* label */
 567         __le16   s_flags;       /* permission flags */
 568         __le32   start_sect;    /* starting sector */
 569         __le32   nr_sects;      /* number of sectors in slice */
 570 };
 571
 572 struct unixware_disklabel {
 573         __le32   d_type;                /* drive type */
 574         __le32   d_magic;                /* the magic number */
 575         __le32   d_version;              /* version number */
 576         char    d_serial[12];           /* serial number of the device */
 577         __le32   d_ncylinders;           /* # of data cylinders per device */
 578         __le32   d_ntracks;              /* # of tracks per cylinder */
 579         __le32   d_nsectors;             /* # of data sectors per track */
 580         __le32   d_secsize;              /* # of bytes per sector */
 581         __le32   d_part_start;           /* # of first sector of this partition */
 582         __le32   d_unknown1[12];         /* ? */
 583         __le32  d_alt_tbl;              /* byte offset of alternate table */
 584         __le32  d_alt_len;              /* byte length of alternate table */
 585         __le32  d_phys_cyl;             /* # of physical cylinders per device */
 586         __le32  d_phys_trk;             /* # of physical tracks per cylinder */
 587         __le32  d_phys_sec;             /* # of physical sectors per track */
 588         __le32  d_phys_bytes;           /* # of physical bytes per sector */
 589         __le32  d_unknown2;             /* ? */
 590         __le32   d_unknown3;             /* ? */
 591         __le32  d_pad[8];               /* pad */
 592
 593         struct unixware_vtoc {
 594                 __le32  v_magic;                /* the magic number */
 595                 __le32  v_version;              /* version number */
 596                 char    v_name[8];              /* volume name */
 597                 __le16  v_nslices;              /* # of slices */
 598                 __le16  v_unknown1;             /* ? */
 599                 __le32  v_reserved[10];         /* reserved */
 600                 struct unixware_slice
 601                         v_slice[UNIXWARE_NUMSLICE];     /* slice headers */
 602         } vtoc;
 603
 604 };  /* 408 */
 605
 606 #endif /* CONFIG_UNIXWARE_DISKLABEL */
 607
 608 #ifdef CONFIG_MINIX_SUBPARTITION
 609 #   define MINIX_NR_SUBPARTITIONS  4
 610 #endif /* CONFIG_MINIX_SUBPARTITION */
 611
 612 #define ADDPART_FLAG_NONE       0
 613 #define ADDPART_FLAG_RAID       1
 614 #define ADDPART_FLAG_WHOLEDISK  2
 615
 616 extern int blk_alloc_devt(struct hd_struct *part, dev_t *devt);
 617 extern void blk_free_devt(dev_t devt);
 618 extern dev_t blk_lookup_devt(const char *name, int partno);
 619 extern char *disk_name (struct gendisk *hd, int partno, char *buf);
 620
 621 extern int disk_expand_part_tbl(struct gendisk *disk, int target);
 622 extern int rescan_partitions(struct gendisk *disk, struct block_device *bdev);
 623 extern int invalidate_partitions(struct gendisk *disk, struct block_device *bdev);
 624 extern struct hd_struct * __must_check add_partition(struct gendisk *disk,
 625                                                      int partno, sector_t start,
 626                                                      sector_t len, int flags,
 627                                                      struct partition_meta_info
 628                                                        *info);
 629 extern void __delete_partition(struct percpu_ref *);
 630 extern void delete_partition(struct gendisk *, int);
 631 extern void printk_all_partitions(void);
 632
 633 extern struct gendisk *alloc_disk_node(int minors, int node_id);
 634 extern struct gendisk *alloc_disk(int minors);
 635 extern struct kobject *get_disk(struct gendisk *disk);
 636 extern void put_disk(struct gendisk *disk);
 637 extern void blk_register_region(dev_t devt, unsigned long range,
 638                         struct module *module,
 639                         struct kobject *(*probe)(dev_t, int *, void *),
 640                         int (*lock)(dev_t, void *),
 641                         void *data);
 642 extern void blk_unregister_region(dev_t devt, unsigned long range);
 643
 644 extern ssize_t part_size_show(struct device *dev,
 645                               struct device_attribute *attr, char *buf);
 646 extern ssize_t part_stat_show(struct device *dev,
 647                               struct device_attribute *attr, char *buf);
 648 extern ssize_t part_inflight_show(struct device *dev,
 649                               struct device_attribute *attr, char *buf);
 650 #ifdef CONFIG_FAIL_MAKE_REQUEST
 651 extern ssize_t part_fail_show(struct device *dev,
 652                               struct device_attribute *attr, char *buf);
 653 extern ssize_t part_fail_store(struct device *dev,
 654                                struct device_attribute *attr,
 655                                const char *buf, size_t count);
 656 #endif /* CONFIG_FAIL_MAKE_REQUEST */
 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 extern void blk_integrity_revalidate(struct gendisk *);
 748 #else   /* CONFIG_BLK_DEV_INTEGRITY */
 749 static inline void blk_integrity_add(struct gendisk *disk) { }
 750 static inline void blk_integrity_del(struct gendisk *disk) { }
 751 static inline void blk_integrity_revalidate(struct gendisk *disk) { }
 752 #endif  /* CONFIG_BLK_DEV_INTEGRITY */
 753
 754 #else /* CONFIG_BLOCK */
 755
 756 static inline void printk_all_partitions(void) { }
 757
 758 static inline dev_t blk_lookup_devt(const char *name, int partno)
 759 {
 760         dev_t devt = MKDEV(0, 0);
 761         return devt;
 762 }
 763
 764 static inline int blk_part_pack_uuid(const u8 *uuid_str, u8 *to)
 765 {
 766         return -EINVAL;
 767 }
 768 #endif /* CONFIG_BLOCK */
 769
 770 #endif /* _LINUX_GENHD_H */