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 #include <asm/local.h>
  21
  22 #ifdef CONFIG_BLOCK
  23
  24 #define dev_to_disk(device)     container_of((device), struct gendisk, part0.__dev)
  25 #define dev_to_part(device)     container_of((device), struct hd_struct, __dev)
  26 #define disk_to_dev(disk)       (&(disk)->part0.__dev)
  27 #define part_to_dev(part)       (&((part)->__dev))
  28
  29 extern struct device_type part_type;
  30 extern struct kobject *block_depr;
  31 extern struct class block_class;
  32
  33 enum {
  34 /* These three have identical behaviour; use the second one if DOS FDISK gets
  35    confused about extended/logical partitions starting past cylinder 1023. */
  36         DOS_EXTENDED_PARTITION = 5,
  37         LINUX_EXTENDED_PARTITION = 0x85,
  38         WIN98_EXTENDED_PARTITION = 0x0f,
  39
  40         SUN_WHOLE_DISK = DOS_EXTENDED_PARTITION,
  41
  42         LINUX_SWAP_PARTITION = 0x82,
  43         LINUX_DATA_PARTITION = 0x83,
  44         LINUX_LVM_PARTITION = 0x8e,
  45         LINUX_RAID_PARTITION = 0xfd,    /* autodetect RAID partition */
  46
  47         SOLARIS_X86_PARTITION = LINUX_SWAP_PARTITION,
  48         NEW_SOLARIS_X86_PARTITION = 0xbf,
  49
  50         DM6_AUX1PARTITION = 0x51,       /* no DDO:  use xlated geom */
  51         DM6_AUX3PARTITION = 0x53,       /* no DDO:  use xlated geom */
  52         DM6_PARTITION = 0x54,           /* has DDO: use xlated geom & offset */
  53         EZD_PARTITION = 0x55,           /* EZ-DRIVE */
  54
  55         FREEBSD_PARTITION = 0xa5,       /* FreeBSD Partition ID */
  56         OPENBSD_PARTITION = 0xa6,       /* OpenBSD Partition ID */
  57         NETBSD_PARTITION = 0xa9,        /* NetBSD Partition ID */
  58         BSDI_PARTITION = 0xb7,          /* BSDI Partition ID */
  59         MINIX_PARTITION = 0x81,         /* Minix Partition ID */
  60         UNIXWARE_PARTITION = 0x63,      /* Same as GNU_HURD and SCO Unix */
  61 };
  62
  63 #define DISK_MAX_PARTS                  256
  64 #define DISK_NAME_LEN                   32
  65
  66 #include <linux/major.h>
  67 #include <linux/device.h>
  68 #include <linux/smp.h>
  69 #include <linux/string.h>
  70 #include <linux/fs.h>
  71 #include <linux/workqueue.h>
  72
  73 struct partition {
  74         unsigned char boot_ind;         /* 0x80 - active */
  75         unsigned char head;             /* starting head */
  76         unsigned char sector;           /* starting sector */
  77         unsigned char cyl;              /* starting cylinder */
  78         unsigned char sys_ind;          /* What partition type */
  79         unsigned char end_head;         /* end head */
  80         unsigned char end_sector;       /* end sector */
  81         unsigned char end_cyl;          /* end cylinder */
  82         __le32 start_sect;      /* starting sector counting from 0 */
  83         __le32 nr_sects;                /* nr of sectors in partition */
  84 } __attribute__((packed));
  85
  86 struct disk_stats {
  87         u64 nsecs[NR_STAT_GROUPS];
  88         unsigned long sectors[NR_STAT_GROUPS];
  89         unsigned long ios[NR_STAT_GROUPS];
  90         unsigned long merges[NR_STAT_GROUPS];
  91         unsigned long io_ticks;
  92         unsigned long time_in_queue;
  93         local_t in_flight[2];
  94 };
  95
  96 #define PARTITION_META_INFO_VOLNAMELTH  64
  97 /*
  98  * Enough for the string representation of any kind of UUID plus NULL.
  99  * EFI UUID is 36 characters. MSDOS UUID is 11 characters.
 100  */
 101 #define PARTITION_META_INFO_UUIDLTH     (UUID_STRING_LEN + 1)
 102
 103 struct partition_meta_info {
 104         char uuid[PARTITION_META_INFO_UUIDLTH];
 105         u8 volname[PARTITION_META_INFO_VOLNAMELTH];
 106 };
 107
 108 struct hd_struct {
 109         sector_t start_sect;
 110         /*
 111          * nr_sects is protected by sequence counter. One might extend a
 112          * partition while IO is happening to it and update of nr_sects
 113          * can be non-atomic on 32bit machines with 64bit sector_t.
 114          */
 115         sector_t nr_sects;
 116         seqcount_t nr_sects_seq;
 117         sector_t alignment_offset;
 118         unsigned int discard_alignment;
 119         struct device __dev;
 120         struct kobject *holder_dir;
 121         int policy, partno;
 122         struct partition_meta_info *info;
 123 #ifdef CONFIG_FAIL_MAKE_REQUEST
 124         int make_it_fail;
 125 #endif
 126         unsigned long stamp;
 127 #ifdef  CONFIG_SMP
 128         struct disk_stats __percpu *dkstats;
 129 #else
 130         struct disk_stats dkstats;
 131 #endif
 132         struct percpu_ref ref;
 133         struct rcu_work rcu_work;
 134 };
 135
 136 #define GENHD_FL_REMOVABLE                      1
 137 /* 2 is unused */
 138 #define GENHD_FL_MEDIA_CHANGE_NOTIFY            4
 139 #define GENHD_FL_CD                             8
 140 #define GENHD_FL_UP                             16
 141 #define GENHD_FL_SUPPRESS_PARTITION_INFO        32
 142 #define GENHD_FL_EXT_DEVT                       64 /* allow extended devt */
 143 #define GENHD_FL_NATIVE_CAPACITY                128
 144 #define GENHD_FL_BLOCK_EVENTS_ON_EXCL_WRITE     256
 145 #define GENHD_FL_NO_PART_SCAN                   512
 146 #define GENHD_FL_HIDDEN                         1024
 147
 148 enum {
 149         DISK_EVENT_MEDIA_CHANGE                 = 1 << 0, /* media changed */
 150         DISK_EVENT_EJECT_REQUEST                = 1 << 1, /* eject requested */
 151 };
 152
 153 struct disk_part_tbl {
 154         struct rcu_head rcu_head;
 155         int len;
 156         struct hd_struct __rcu *last_lookup;
 157         struct hd_struct __rcu *part[];
 158 };
 159
 160 struct disk_events;
 161 struct badblocks;
 162
 163 #if defined(CONFIG_BLK_DEV_INTEGRITY)
 164
 165 struct blk_integrity {
 166         const struct blk_integrity_profile      *profile;
 167         unsigned char                           flags;
 168         unsigned char                           tuple_size;
 169         unsigned char                           interval_exp;
 170         unsigned char                           tag_size;
 171 };
 172
 173 #endif  /* CONFIG_BLK_DEV_INTEGRITY */
 174
 175 struct gendisk {
 176         /* major, first_minor and minors are input parameters only,
 177          * don't use directly.  Use disk_devt() and disk_max_parts().
 178          */
 179         int major;                      /* major number of driver */
 180         int first_minor;
 181         int minors;                     /* maximum number of minors, =1 for
 182                                          * disks that can't be partitioned. */
 183
 184         char disk_name[DISK_NAME_LEN];  /* name of major driver */
 185         char *(*devnode)(struct gendisk *gd, umode_t *mode);
 186
 187         unsigned int events;            /* supported events */
 188         unsigned int async_events;      /* async events, subset of all */
 189
 190         /* Array of pointers to partitions indexed by partno.
 191          * Protected with matching bdev lock but stat and other
 192          * non-critical accesses use RCU.  Always access through
 193          * helpers.
 194          */
 195         struct disk_part_tbl __rcu *part_tbl;
 196         struct hd_struct part0;
 197
 198         const struct block_device_operations *fops;
 199         struct request_queue *queue;
 200         void *private_data;
 201
 202         int flags;
 203         struct rw_semaphore lookup_sem;
 204         struct kobject *slave_dir;
 205
 206         struct timer_rand_state *random;
 207         atomic_t sync_io;               /* RAID */
 208         struct disk_events *ev;
 209 #ifdef  CONFIG_BLK_DEV_INTEGRITY
 210         struct kobject integrity_kobj;
 211 #endif  /* CONFIG_BLK_DEV_INTEGRITY */
 212         int node_id;
 213         struct badblocks *bb;
 214         struct lockdep_map lockdep_map;
 215 };
 216
 217 static inline struct gendisk *part_to_disk(struct hd_struct *part)
 218 {
 219         if (likely(part)) {
 220                 if (part->partno)
 221                         return dev_to_disk(part_to_dev(part)->parent);
 222                 else
 223                         return dev_to_disk(part_to_dev(part));
 224         }
 225         return NULL;
 226 }
 227
 228 static inline int disk_max_parts(struct gendisk *disk)
 229 {
 230         if (disk->flags & GENHD_FL_EXT_DEVT)
 231                 return DISK_MAX_PARTS;
 232         return disk->minors;
 233 }
 234
 235 static inline bool disk_part_scan_enabled(struct gendisk *disk)
 236 {
 237         return disk_max_parts(disk) > 1 &&
 238                 !(disk->flags & GENHD_FL_NO_PART_SCAN);
 239 }
 240
 241 static inline dev_t disk_devt(struct gendisk *disk)
 242 {
 243         return MKDEV(disk->major, disk->first_minor);
 244 }
 245
 246 static inline dev_t part_devt(struct hd_struct *part)
 247 {
 248         return part_to_dev(part)->devt;
 249 }
 250
 251 extern struct hd_struct *__disk_get_part(struct gendisk *disk, int partno);
 252 extern struct hd_struct *disk_get_part(struct gendisk *disk, int partno);
 253
 254 static inline void disk_put_part(struct hd_struct *part)
 255 {
 256         if (likely(part))
 257                 put_device(part_to_dev(part));
 258 }
 259
 260 /*
 261  * Smarter partition iterator without context limits.
 262  */
 263 #define DISK_PITER_REVERSE      (1 << 0) /* iterate in the reverse direction */
 264 #define DISK_PITER_INCL_EMPTY   (1 << 1) /* include 0-sized parts */
 265 #define DISK_PITER_INCL_PART0   (1 << 2) /* include partition 0 */
 266 #define DISK_PITER_INCL_EMPTY_PART0 (1 << 3) /* include empty partition 0 */
 267
 268 struct disk_part_iter {
 269         struct gendisk          *disk;
 270         struct hd_struct        *part;
 271         int                     idx;
 272         unsigned int            flags;
 273 };
 274
 275 extern void disk_part_iter_init(struct disk_part_iter *piter,
 276                                  struct gendisk *disk, unsigned int flags);
 277 extern struct hd_struct *disk_part_iter_next(struct disk_part_iter *piter);
 278 extern void disk_part_iter_exit(struct disk_part_iter *piter);
 279
 280 extern struct hd_struct *disk_map_sector_rcu(struct gendisk *disk,
 281                                              sector_t sector);
 282
 283 /*
 284  * Macros to operate on percpu disk statistics:
 285  *
 286  * {disk|part|all}_stat_{add|sub|inc|dec}() modify the stat counters
 287  * and should be called between disk_stat_lock() and
 288  * disk_stat_unlock().
 289  *
 290  * part_stat_read() can be called at any time.
 291  *
 292  * part_stat_{add|set_all}() and {init|free}_part_stats are for
 293  * internal use only.
 294  */
 295 #ifdef  CONFIG_SMP
 296 #define part_stat_lock()        ({ rcu_read_lock(); get_cpu(); })
 297 #define part_stat_unlock()      do { put_cpu(); rcu_read_unlock(); } while (0)
 298
 299 #define part_stat_get_cpu(part, field, cpu)                                     \
 300         (per_cpu_ptr((part)->dkstats, (cpu))->field)
 301
 302 #define part_stat_get(part, field)                                      \
 303         part_stat_get_cpu(part, field, smp_processor_id())
 304
 305 #define part_stat_read(part, field)                                     \
 306 ({                                                                      \
 307         typeof((part)->dkstats->field) res = 0;                         \
 308         unsigned int _cpu;                                              \
 309         for_each_possible_cpu(_cpu)                                     \
 310                 res += per_cpu_ptr((part)->dkstats, _cpu)->field;       \
 311         res;                                                            \
 312 })
 313
 314 static inline void part_stat_set_all(struct hd_struct *part, int value)
 315 {
 316         int i;
 317
 318         for_each_possible_cpu(i)
 319                 memset(per_cpu_ptr(part->dkstats, i), value,
 320                                 sizeof(struct disk_stats));
 321 }
 322
 323 static inline int init_part_stats(struct hd_struct *part)
 324 {
 325         part->dkstats = alloc_percpu(struct disk_stats);
 326         if (!part->dkstats)
 327                 return 0;
 328         return 1;
 329 }
 330
 331 static inline void free_part_stats(struct hd_struct *part)
 332 {
 333         free_percpu(part->dkstats);
 334 }
 335
 336 #else /* !CONFIG_SMP */
 337 #define part_stat_lock()        ({ rcu_read_lock(); 0; })
 338 #define part_stat_unlock()      rcu_read_unlock()
 339
 340 #define part_stat_get(part, field)              ((part)->dkstats.field)
 341 #define part_stat_get_cpu(part, field, cpu)     part_stat_get(part, field)
 342 #define part_stat_read(part, field)             part_stat_get(part, field)
 343
 344 static inline void part_stat_set_all(struct hd_struct *part, int value)
 345 {
 346         memset(&part->dkstats, value, sizeof(struct disk_stats));
 347 }
 348
 349 static inline int init_part_stats(struct hd_struct *part)
 350 {
 351         return 1;
 352 }
 353
 354 static inline void free_part_stats(struct hd_struct *part)
 355 {
 356 }
 357
 358 #endif /* CONFIG_SMP */
 359
 360 #define part_stat_read_msecs(part, which)                               \
 361         div_u64(part_stat_read(part, nsecs[which]), NSEC_PER_MSEC)
 362
 363 #define part_stat_read_accum(part, field)                               \
 364         (part_stat_read(part, field[STAT_READ]) +                       \
 365          part_stat_read(part, field[STAT_WRITE]) +                      \
 366          part_stat_read(part, field[STAT_DISCARD]))
 367
 368 #define __part_stat_add(part, field, addnd)                             \
 369         (part_stat_get(part, field) += (addnd))
 370
 371 #define part_stat_add(part, field, addnd)       do {                    \
 372         __part_stat_add((part), field, addnd);                          \
 373         if ((part)->partno)                                             \
 374                 __part_stat_add(&part_to_disk((part))->part0,           \
 375                                 field, addnd);                          \
 376 } while (0)
 377
 378 #define part_stat_dec(gendiskp, field)                                  \
 379         part_stat_add(gendiskp, field, -1)
 380 #define part_stat_inc(gendiskp, field)                                  \
 381         part_stat_add(gendiskp, field, 1)
 382 #define part_stat_sub(gendiskp, field, subnd)                           \
 383         part_stat_add(gendiskp, field, -subnd)
 384
 385 #define part_stat_local_dec(gendiskp, field)                            \
 386         local_dec(&(part_stat_get(gendiskp, field)))
 387 #define part_stat_local_inc(gendiskp, field)                            \
 388         local_inc(&(part_stat_get(gendiskp, field)))
 389 #define part_stat_local_read(gendiskp, field)                           \
 390         local_read(&(part_stat_get(gendiskp, field)))
 391 #define part_stat_local_read_cpu(gendiskp, field, cpu)                  \
 392         local_read(&(part_stat_get_cpu(gendiskp, field, cpu)))
 393
 394 unsigned int part_in_flight(struct request_queue *q, struct hd_struct *part);
 395 void part_in_flight_rw(struct request_queue *q, struct hd_struct *part,
 396                        unsigned int inflight[2]);
 397 void part_dec_in_flight(struct request_queue *q, struct hd_struct *part,
 398                         int rw);
 399 void part_inc_in_flight(struct request_queue *q, struct hd_struct *part,
 400                         int rw);
 401
 402 static inline struct partition_meta_info *alloc_part_info(struct gendisk *disk)
 403 {
 404         if (disk)
 405                 return kzalloc_node(sizeof(struct partition_meta_info),
 406                                     GFP_KERNEL, disk->node_id);
 407         return kzalloc(sizeof(struct partition_meta_info), GFP_KERNEL);
 408 }
 409
 410 static inline void free_part_info(struct hd_struct *part)
 411 {
 412         kfree(part->info);
 413 }
 414
 415 void update_io_ticks(struct hd_struct *part, unsigned long now);
 416
 417 /* block/genhd.c */
 418 extern void device_add_disk(struct device *parent, struct gendisk *disk,
 419                             const struct attribute_group **groups);
 420 static inline void add_disk(struct gendisk *disk)
 421 {
 422         device_add_disk(NULL, disk, NULL);
 423 }
 424 extern void device_add_disk_no_queue_reg(struct device *parent, struct gendisk *disk);
 425 static inline void add_disk_no_queue_reg(struct gendisk *disk)
 426 {
 427         device_add_disk_no_queue_reg(NULL, disk);
 428 }
 429
 430 extern void del_gendisk(struct gendisk *gp);
 431 extern struct gendisk *get_gendisk(dev_t dev, int *partno);
 432 extern struct block_device *bdget_disk(struct gendisk *disk, int partno);
 433
 434 extern void set_device_ro(struct block_device *bdev, int flag);
 435 extern void set_disk_ro(struct gendisk *disk, int flag);
 436
 437 static inline int get_disk_ro(struct gendisk *disk)
 438 {
 439         return disk->part0.policy;
 440 }
 441
 442 extern void disk_block_events(struct gendisk *disk);
 443 extern void disk_unblock_events(struct gendisk *disk);
 444 extern void disk_flush_events(struct gendisk *disk, unsigned int mask);
 445 extern unsigned int disk_clear_events(struct gendisk *disk, unsigned int mask);
 446
 447 /* drivers/char/random.c */
 448 extern void add_disk_randomness(struct gendisk *disk) __latent_entropy;
 449 extern void rand_initialize_disk(struct gendisk *disk);
 450
 451 static inline sector_t get_start_sect(struct block_device *bdev)
 452 {
 453         return bdev->bd_part->start_sect;
 454 }
 455 static inline sector_t get_capacity(struct gendisk *disk)
 456 {
 457         return disk->part0.nr_sects;
 458 }
 459 static inline void set_capacity(struct gendisk *disk, sector_t size)
 460 {
 461         disk->part0.nr_sects = size;
 462 }
 463
 464 #ifdef CONFIG_SOLARIS_X86_PARTITION
 465
 466 #define SOLARIS_X86_NUMSLICE    16
 467 #define SOLARIS_X86_VTOC_SANE   (0x600DDEEEUL)
 468
 469 struct solaris_x86_slice {
 470         __le16 s_tag;           /* ID tag of partition */
 471         __le16 s_flag;          /* permission flags */
 472         __le32 s_start;         /* start sector no of partition */
 473         __le32 s_size;          /* # of blocks in partition */
 474 };
 475
 476 struct solaris_x86_vtoc {
 477         unsigned int v_bootinfo[3];     /* info needed by mboot (unsupported) */
 478         __le32 v_sanity;                /* to verify vtoc sanity */
 479         __le32 v_version;               /* layout version */
 480         char    v_volume[8];            /* volume name */
 481         __le16  v_sectorsz;             /* sector size in bytes */
 482         __le16  v_nparts;               /* number of partitions */
 483         unsigned int v_reserved[10];    /* free space */
 484         struct solaris_x86_slice
 485                 v_slice[SOLARIS_X86_NUMSLICE]; /* slice headers */
 486         unsigned int timestamp[SOLARIS_X86_NUMSLICE]; /* timestamp (unsupported) */
 487         char    v_asciilabel[128];      /* for compatibility */
 488 };
 489
 490 #endif /* CONFIG_SOLARIS_X86_PARTITION */
 491
 492 #ifdef CONFIG_BSD_DISKLABEL
 493 /*
 494  * BSD disklabel support by Yossi Gottlieb <yogo@math.tau.ac.il>
 495  * updated by Marc Espie <Marc.Espie@openbsd.org>
 496  */
 497
 498 /* check against BSD src/sys/sys/disklabel.h for consistency */
 499
 500 #define BSD_DISKMAGIC   (0x82564557UL)  /* The disk magic number */
 501 #define BSD_MAXPARTITIONS       16
 502 #define OPENBSD_MAXPARTITIONS   16
 503 #define BSD_FS_UNUSED           0       /* disklabel unused partition entry ID */
 504 struct bsd_disklabel {
 505         __le32  d_magic;                /* the magic number */
 506         __s16   d_type;                 /* drive type */
 507         __s16   d_subtype;              /* controller/d_type specific */
 508         char    d_typename[16];         /* type name, e.g. "eagle" */
 509         char    d_packname[16];                 /* pack identifier */
 510         __u32   d_secsize;              /* # of bytes per sector */
 511         __u32   d_nsectors;             /* # of data sectors per track */
 512         __u32   d_ntracks;              /* # of tracks per cylinder */
 513         __u32   d_ncylinders;           /* # of data cylinders per unit */
 514         __u32   d_secpercyl;            /* # of data sectors per cylinder */
 515         __u32   d_secperunit;           /* # of data sectors per unit */
 516         __u16   d_sparespertrack;       /* # of spare sectors per track */
 517         __u16   d_sparespercyl;         /* # of spare sectors per cylinder */
 518         __u32   d_acylinders;           /* # of alt. cylinders per unit */
 519         __u16   d_rpm;                  /* rotational speed */
 520         __u16   d_interleave;           /* hardware sector interleave */
 521         __u16   d_trackskew;            /* sector 0 skew, per track */
 522         __u16   d_cylskew;              /* sector 0 skew, per cylinder */
 523         __u32   d_headswitch;           /* head switch time, usec */
 524         __u32   d_trkseek;              /* track-to-track seek, usec */
 525         __u32   d_flags;                /* generic flags */
 526 #define NDDATA 5
 527         __u32   d_drivedata[NDDATA];    /* drive-type specific information */
 528 #define NSPARE 5
 529         __u32   d_spare[NSPARE];        /* reserved for future use */
 530         __le32  d_magic2;               /* the magic number (again) */
 531         __le16  d_checksum;             /* xor of data incl. partitions */
 532
 533                         /* filesystem and partition information: */
 534         __le16  d_npartitions;          /* number of partitions in following */
 535         __le32  d_bbsize;               /* size of boot area at sn0, bytes */
 536         __le32  d_sbsize;               /* max size of fs superblock, bytes */
 537         struct  bsd_partition {         /* the partition table */
 538                 __le32  p_size;         /* number of sectors in partition */
 539                 __le32  p_offset;       /* starting sector */
 540                 __le32  p_fsize;        /* filesystem basic fragment size */
 541                 __u8    p_fstype;       /* filesystem type, see below */
 542                 __u8    p_frag;         /* filesystem fragments per block */
 543                 __le16  p_cpg;          /* filesystem cylinders per group */
 544         } d_partitions[BSD_MAXPARTITIONS];      /* actually may be more */
 545 };
 546
 547 #endif  /* CONFIG_BSD_DISKLABEL */
 548
 549 #ifdef CONFIG_UNIXWARE_DISKLABEL
 550 /*
 551  * Unixware slices support by Andrzej Krzysztofowicz <ankry@mif.pg.gda.pl>
 552  * and Krzysztof G. Baranowski <kgb@knm.org.pl>
 553  */
 554
 555 #define UNIXWARE_DISKMAGIC     (0xCA5E600DUL)   /* The disk magic number */
 556 #define UNIXWARE_DISKMAGIC2    (0x600DDEEEUL)   /* The slice table magic nr */
 557 #define UNIXWARE_NUMSLICE      16
 558 #define UNIXWARE_FS_UNUSED     0                /* Unused slice entry ID */
 559
 560 struct unixware_slice {
 561         __le16   s_label;       /* label */
 562         __le16   s_flags;       /* permission flags */
 563         __le32   start_sect;    /* starting sector */
 564         __le32   nr_sects;      /* number of sectors in slice */
 565 };
 566
 567 struct unixware_disklabel {
 568         __le32   d_type;                /* drive type */
 569         __le32   d_magic;                /* the magic number */
 570         __le32   d_version;              /* version number */
 571         char    d_serial[12];           /* serial number of the device */
 572         __le32   d_ncylinders;           /* # of data cylinders per device */
 573         __le32   d_ntracks;              /* # of tracks per cylinder */
 574         __le32   d_nsectors;             /* # of data sectors per track */
 575         __le32   d_secsize;              /* # of bytes per sector */
 576         __le32   d_part_start;           /* # of first sector of this partition */
 577         __le32   d_unknown1[12];         /* ? */
 578         __le32  d_alt_tbl;              /* byte offset of alternate table */
 579         __le32  d_alt_len;              /* byte length of alternate table */
 580         __le32  d_phys_cyl;             /* # of physical cylinders per device */
 581         __le32  d_phys_trk;             /* # of physical tracks per cylinder */
 582         __le32  d_phys_sec;             /* # of physical sectors per track */
 583         __le32  d_phys_bytes;           /* # of physical bytes per sector */
 584         __le32  d_unknown2;             /* ? */
 585         __le32   d_unknown3;             /* ? */
 586         __le32  d_pad[8];               /* pad */
 587
 588         struct unixware_vtoc {
 589                 __le32  v_magic;                /* the magic number */
 590                 __le32  v_version;              /* version number */
 591                 char    v_name[8];              /* volume name */
 592                 __le16  v_nslices;              /* # of slices */
 593                 __le16  v_unknown1;             /* ? */
 594                 __le32  v_reserved[10];         /* reserved */
 595                 struct unixware_slice
 596                         v_slice[UNIXWARE_NUMSLICE];     /* slice headers */
 597         } vtoc;
 598
 599 };  /* 408 */
 600
 601 #endif /* CONFIG_UNIXWARE_DISKLABEL */
 602
 603 #ifdef CONFIG_MINIX_SUBPARTITION
 604 #   define MINIX_NR_SUBPARTITIONS  4
 605 #endif /* CONFIG_MINIX_SUBPARTITION */
 606
 607 #define ADDPART_FLAG_NONE       0
 608 #define ADDPART_FLAG_RAID       1
 609 #define ADDPART_FLAG_WHOLEDISK  2
 610
 611 extern int blk_alloc_devt(struct hd_struct *part, dev_t *devt);
 612 extern void blk_free_devt(dev_t devt);
 613 extern dev_t blk_lookup_devt(const char *name, int partno);
 614 extern char *disk_name (struct gendisk *hd, int partno, char *buf);
 615
 616 extern int disk_expand_part_tbl(struct gendisk *disk, int target);
 617 extern int rescan_partitions(struct gendisk *disk, struct block_device *bdev);
 618 extern int invalidate_partitions(struct gendisk *disk, struct block_device *bdev);
 619 extern struct hd_struct * __must_check add_partition(struct gendisk *disk,
 620                                                      int partno, sector_t start,
 621                                                      sector_t len, int flags,
 622                                                      struct partition_meta_info
 623                                                        *info);
 624 extern void __delete_partition(struct percpu_ref *);
 625 extern void delete_partition(struct gendisk *, int);
 626 extern void printk_all_partitions(void);
 627
 628 extern struct gendisk *__alloc_disk_node(int minors, int node_id);
 629 extern struct kobject *get_disk_and_module(struct gendisk *disk);
 630 extern void put_disk(struct gendisk *disk);
 631 extern void put_disk_and_module(struct gendisk *disk);
 632 extern void blk_register_region(dev_t devt, unsigned long range,
 633                         struct module *module,
 634                         struct kobject *(*probe)(dev_t, int *, void *),
 635                         int (*lock)(dev_t, void *),
 636                         void *data);
 637 extern void blk_unregister_region(dev_t devt, unsigned long range);
 638
 639 extern ssize_t part_size_show(struct device *dev,
 640                               struct device_attribute *attr, char *buf);
 641 extern ssize_t part_stat_show(struct device *dev,
 642                               struct device_attribute *attr, char *buf);
 643 extern ssize_t part_inflight_show(struct device *dev,
 644                               struct device_attribute *attr, char *buf);
 645 #ifdef CONFIG_FAIL_MAKE_REQUEST
 646 extern ssize_t part_fail_show(struct device *dev,
 647                               struct device_attribute *attr, char *buf);
 648 extern ssize_t part_fail_store(struct device *dev,
 649                                struct device_attribute *attr,
 650                                const char *buf, size_t count);
 651 #endif /* CONFIG_FAIL_MAKE_REQUEST */
 652
 653 #define alloc_disk_node(minors, node_id)                                \
 654 ({                                                                      \
 655         static struct lock_class_key __key;                             \
 656         const char *__name;                                             \
 657         struct gendisk *__disk;                                         \
 658                                                                         \
 659         __name = "(gendisk_completion)"#minors"("#node_id")";           \
 660                                                                         \
 661         __disk = __alloc_disk_node(minors, node_id);                    \
 662                                                                         \
 663         if (__disk)                                                     \
 664                 lockdep_init_map(&__disk->lockdep_map, __name, &__key, 0); \
 665                                                                         \
 666         __disk;                                                         \
 667 })
 668
 669 #define alloc_disk(minors) alloc_disk_node(minors, NUMA_NO_NODE)
 670
 671 static inline int hd_ref_init(struct hd_struct *part)
 672 {
 673         if (percpu_ref_init(&part->ref, __delete_partition, 0,
 674                                 GFP_KERNEL))
 675                 return -ENOMEM;
 676         return 0;
 677 }
 678
 679 static inline void hd_struct_get(struct hd_struct *part)
 680 {
 681         percpu_ref_get(&part->ref);
 682 }
 683
 684 static inline int hd_struct_try_get(struct hd_struct *part)
 685 {
 686         return percpu_ref_tryget_live(&part->ref);
 687 }
 688
 689 static inline void hd_struct_put(struct hd_struct *part)
 690 {
 691         percpu_ref_put(&part->ref);
 692 }
 693
 694 static inline void hd_struct_kill(struct hd_struct *part)
 695 {
 696         percpu_ref_kill(&part->ref);
 697 }
 698
 699 static inline void hd_free_part(struct hd_struct *part)
 700 {
 701         free_part_stats(part);
 702         free_part_info(part);
 703         percpu_ref_exit(&part->ref);
 704 }
 705
 706 /*
 707  * Any access of part->nr_sects which is not protected by partition
 708  * bd_mutex or gendisk bdev bd_mutex, should be done using this
 709  * accessor function.
 710  *
 711  * Code written along the lines of i_size_read() and i_size_write().
 712  * CONFIG_PREEMPT case optimizes the case of UP kernel with preemption
 713  * on.
 714  */
 715 static inline sector_t part_nr_sects_read(struct hd_struct *part)
 716 {
 717 #if BITS_PER_LONG==32 && defined(CONFIG_SMP)
 718         sector_t nr_sects;
 719         unsigned seq;
 720         do {
 721                 seq = read_seqcount_begin(&part->nr_sects_seq);
 722                 nr_sects = part->nr_sects;
 723         } while (read_seqcount_retry(&part->nr_sects_seq, seq));
 724         return nr_sects;
 725 #elif BITS_PER_LONG==32 && defined(CONFIG_PREEMPT)
 726         sector_t nr_sects;
 727
 728         preempt_disable();
 729         nr_sects = part->nr_sects;
 730         preempt_enable();
 731         return nr_sects;
 732 #else
 733         return part->nr_sects;
 734 #endif
 735 }
 736
 737 /*
 738  * Should be called with mutex lock held (typically bd_mutex) of partition
 739  * to provide mutual exlusion among writers otherwise seqcount might be
 740  * left in wrong state leaving the readers spinning infinitely.
 741  */
 742 static inline void part_nr_sects_write(struct hd_struct *part, sector_t size)
 743 {
 744 #if BITS_PER_LONG==32 && defined(CONFIG_SMP)
 745         write_seqcount_begin(&part->nr_sects_seq);
 746         part->nr_sects = size;
 747         write_seqcount_end(&part->nr_sects_seq);
 748 #elif BITS_PER_LONG==32 && defined(CONFIG_PREEMPT)
 749         preempt_disable();
 750         part->nr_sects = size;
 751         preempt_enable();
 752 #else
 753         part->nr_sects = size;
 754 #endif
 755 }
 756
 757 #if defined(CONFIG_BLK_DEV_INTEGRITY)
 758 extern void blk_integrity_add(struct gendisk *);
 759 extern void blk_integrity_del(struct gendisk *);
 760 #else   /* CONFIG_BLK_DEV_INTEGRITY */
 761 static inline void blk_integrity_add(struct gendisk *disk) { }
 762 static inline void blk_integrity_del(struct gendisk *disk) { }
 763 #endif  /* CONFIG_BLK_DEV_INTEGRITY */
 764
 765 #else /* CONFIG_BLOCK */
 766
 767 static inline void printk_all_partitions(void) { }
 768
 769 static inline dev_t blk_lookup_devt(const char *name, int partno)
 770 {
 771         dev_t devt = MKDEV(0, 0);
 772         return devt;
 773 }
 774 #endif /* CONFIG_BLOCK */
 775
 776 #endif /* _LINUX_GENHD_H */