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 enum {
 154         /* Poll even if events_poll_msecs is unset */
 155         DISK_EVENT_FLAG_POLL                    = 1 << 0,
 156         /* Forward events to udev */
 157         DISK_EVENT_FLAG_UEVENT                  = 1 << 1,
 158 };
 159
 160 struct disk_part_tbl {
 161         struct rcu_head rcu_head;
 162         int len;
 163         struct hd_struct __rcu *last_lookup;
 164         struct hd_struct __rcu *part[];
 165 };
 166
 167 struct disk_events;
 168 struct badblocks;
 169
 170 #if defined(CONFIG_BLK_DEV_INTEGRITY)
 171
 172 struct blk_integrity {
 173         const struct blk_integrity_profile      *profile;
 174         unsigned char                           flags;
 175         unsigned char                           tuple_size;
 176         unsigned char                           interval_exp;
 177         unsigned char                           tag_size;
 178 };
 179
 180 #endif  /* CONFIG_BLK_DEV_INTEGRITY */
 181
 182 struct gendisk {
 183         /* major, first_minor and minors are input parameters only,
 184          * don't use directly.  Use disk_devt() and disk_max_parts().
 185          */
 186         int major;                      /* major number of driver */
 187         int first_minor;
 188         int minors;                     /* maximum number of minors, =1 for
 189                                          * disks that can't be partitioned. */
 190
 191         char disk_name[DISK_NAME_LEN];  /* name of major driver */
 192         char *(*devnode)(struct gendisk *gd, umode_t *mode);
 193
 194         unsigned short events;          /* supported events */
 195         unsigned short event_flags;     /* flags related to event processing */
 196
 197         /* Array of pointers to partitions indexed by partno.
 198          * Protected with matching bdev lock but stat and other
 199          * non-critical accesses use RCU.  Always access through
 200          * helpers.
 201          */
 202         struct disk_part_tbl __rcu *part_tbl;
 203         struct hd_struct part0;
 204
 205         const struct block_device_operations *fops;
 206         struct request_queue *queue;
 207         void *private_data;
 208
 209         int flags;
 210         struct rw_semaphore lookup_sem;
 211         struct kobject *slave_dir;
 212
 213         struct timer_rand_state *random;
 214         atomic_t sync_io;               /* RAID */
 215         struct disk_events *ev;
 216 #ifdef  CONFIG_BLK_DEV_INTEGRITY
 217         struct kobject integrity_kobj;
 218 #endif  /* CONFIG_BLK_DEV_INTEGRITY */
 219         int node_id;
 220         struct badblocks *bb;
 221         struct lockdep_map lockdep_map;
 222 };
 223
 224 static inline struct gendisk *part_to_disk(struct hd_struct *part)
 225 {
 226         if (likely(part)) {
 227                 if (part->partno)
 228                         return dev_to_disk(part_to_dev(part)->parent);
 229                 else
 230                         return dev_to_disk(part_to_dev(part));
 231         }
 232         return NULL;
 233 }
 234
 235 static inline int disk_max_parts(struct gendisk *disk)
 236 {
 237         if (disk->flags & GENHD_FL_EXT_DEVT)
 238                 return DISK_MAX_PARTS;
 239         return disk->minors;
 240 }
 241
 242 static inline bool disk_part_scan_enabled(struct gendisk *disk)
 243 {
 244         return disk_max_parts(disk) > 1 &&
 245                 !(disk->flags & GENHD_FL_NO_PART_SCAN);
 246 }
 247
 248 static inline bool disk_has_partitions(struct gendisk *disk)
 249 {
 250         bool ret = false;
 251
 252         rcu_read_lock();
 253         if (rcu_dereference(disk->part_tbl)->len > 1)
 254                 ret = true;
 255         rcu_read_unlock();
 256
 257         return ret;
 258 }
 259
 260 static inline dev_t disk_devt(struct gendisk *disk)
 261 {
 262         return MKDEV(disk->major, disk->first_minor);
 263 }
 264
 265 static inline dev_t part_devt(struct hd_struct *part)
 266 {
 267         return part_to_dev(part)->devt;
 268 }
 269
 270 extern struct hd_struct *__disk_get_part(struct gendisk *disk, int partno);
 271 extern struct hd_struct *disk_get_part(struct gendisk *disk, int partno);
 272
 273 static inline void disk_put_part(struct hd_struct *part)
 274 {
 275         if (likely(part))
 276                 put_device(part_to_dev(part));
 277 }
 278
 279 /*
 280  * Smarter partition iterator without context limits.
 281  */
 282 #define DISK_PITER_REVERSE      (1 << 0) /* iterate in the reverse direction */
 283 #define DISK_PITER_INCL_EMPTY   (1 << 1) /* include 0-sized parts */
 284 #define DISK_PITER_INCL_PART0   (1 << 2) /* include partition 0 */
 285 #define DISK_PITER_INCL_EMPTY_PART0 (1 << 3) /* include empty partition 0 */
 286
 287 struct disk_part_iter {
 288         struct gendisk          *disk;
 289         struct hd_struct        *part;
 290         int                     idx;
 291         unsigned int            flags;
 292 };
 293
 294 extern void disk_part_iter_init(struct disk_part_iter *piter,
 295                                  struct gendisk *disk, unsigned int flags);
 296 extern struct hd_struct *disk_part_iter_next(struct disk_part_iter *piter);
 297 extern void disk_part_iter_exit(struct disk_part_iter *piter);
 298
 299 extern struct hd_struct *disk_map_sector_rcu(struct gendisk *disk,
 300                                              sector_t sector);
 301
 302 /*
 303  * Macros to operate on percpu disk statistics:
 304  *
 305  * {disk|part|all}_stat_{add|sub|inc|dec}() modify the stat counters
 306  * and should be called between disk_stat_lock() and
 307  * disk_stat_unlock().
 308  *
 309  * part_stat_read() can be called at any time.
 310  *
 311  * part_stat_{add|set_all}() and {init|free}_part_stats are for
 312  * internal use only.
 313  */
 314 #ifdef  CONFIG_SMP
 315 #define part_stat_lock()        ({ rcu_read_lock(); get_cpu(); })
 316 #define part_stat_unlock()      do { put_cpu(); rcu_read_unlock(); } while (0)
 317
 318 #define part_stat_get_cpu(part, field, cpu)                                     \
 319         (per_cpu_ptr((part)->dkstats, (cpu))->field)
 320
 321 #define part_stat_get(part, field)                                      \
 322         part_stat_get_cpu(part, field, smp_processor_id())
 323
 324 #define part_stat_read(part, field)                                     \
 325 ({                                                                      \
 326         typeof((part)->dkstats->field) res = 0;                         \
 327         unsigned int _cpu;                                              \
 328         for_each_possible_cpu(_cpu)                                     \
 329                 res += per_cpu_ptr((part)->dkstats, _cpu)->field;       \
 330         res;                                                            \
 331 })
 332
 333 static inline void part_stat_set_all(struct hd_struct *part, int value)
 334 {
 335         int i;
 336
 337         for_each_possible_cpu(i)
 338                 memset(per_cpu_ptr(part->dkstats, i), value,
 339                                 sizeof(struct disk_stats));
 340 }
 341
 342 static inline int init_part_stats(struct hd_struct *part)
 343 {
 344         part->dkstats = alloc_percpu(struct disk_stats);
 345         if (!part->dkstats)
 346                 return 0;
 347         return 1;
 348 }
 349
 350 static inline void free_part_stats(struct hd_struct *part)
 351 {
 352         free_percpu(part->dkstats);
 353 }
 354
 355 #else /* !CONFIG_SMP */
 356 #define part_stat_lock()        ({ rcu_read_lock(); 0; })
 357 #define part_stat_unlock()      rcu_read_unlock()
 358
 359 #define part_stat_get(part, field)              ((part)->dkstats.field)
 360 #define part_stat_get_cpu(part, field, cpu)     part_stat_get(part, field)
 361 #define part_stat_read(part, field)             part_stat_get(part, field)
 362
 363 static inline void part_stat_set_all(struct hd_struct *part, int value)
 364 {
 365         memset(&part->dkstats, value, sizeof(struct disk_stats));
 366 }
 367
 368 static inline int init_part_stats(struct hd_struct *part)
 369 {
 370         return 1;
 371 }
 372
 373 static inline void free_part_stats(struct hd_struct *part)
 374 {
 375 }
 376
 377 #endif /* CONFIG_SMP */
 378
 379 #define part_stat_read_msecs(part, which)                               \
 380         div_u64(part_stat_read(part, nsecs[which]), NSEC_PER_MSEC)
 381
 382 #define part_stat_read_accum(part, field)                               \
 383         (part_stat_read(part, field[STAT_READ]) +                       \
 384          part_stat_read(part, field[STAT_WRITE]) +                      \
 385          part_stat_read(part, field[STAT_DISCARD]))
 386
 387 #define __part_stat_add(part, field, addnd)                             \
 388         (part_stat_get(part, field) += (addnd))
 389
 390 #define part_stat_add(part, field, addnd)       do {                    \
 391         __part_stat_add((part), field, addnd);                          \
 392         if ((part)->partno)                                             \
 393                 __part_stat_add(&part_to_disk((part))->part0,           \
 394                                 field, addnd);                          \
 395 } while (0)
 396
 397 #define part_stat_dec(gendiskp, field)                                  \
 398         part_stat_add(gendiskp, field, -1)
 399 #define part_stat_inc(gendiskp, field)                                  \
 400         part_stat_add(gendiskp, field, 1)
 401 #define part_stat_sub(gendiskp, field, subnd)                           \
 402         part_stat_add(gendiskp, field, -subnd)
 403
 404 #define part_stat_local_dec(gendiskp, field)                            \
 405         local_dec(&(part_stat_get(gendiskp, field)))
 406 #define part_stat_local_inc(gendiskp, field)                            \
 407         local_inc(&(part_stat_get(gendiskp, field)))
 408 #define part_stat_local_read(gendiskp, field)                           \
 409         local_read(&(part_stat_get(gendiskp, field)))
 410 #define part_stat_local_read_cpu(gendiskp, field, cpu)                  \
 411         local_read(&(part_stat_get_cpu(gendiskp, field, cpu)))
 412
 413 unsigned int part_in_flight(struct request_queue *q, struct hd_struct *part);
 414 void part_in_flight_rw(struct request_queue *q, struct hd_struct *part,
 415                        unsigned int inflight[2]);
 416 void part_dec_in_flight(struct request_queue *q, struct hd_struct *part,
 417                         int rw);
 418 void part_inc_in_flight(struct request_queue *q, struct hd_struct *part,
 419                         int rw);
 420
 421 static inline struct partition_meta_info *alloc_part_info(struct gendisk *disk)
 422 {
 423         if (disk)
 424                 return kzalloc_node(sizeof(struct partition_meta_info),
 425                                     GFP_KERNEL, disk->node_id);
 426         return kzalloc(sizeof(struct partition_meta_info), GFP_KERNEL);
 427 }
 428
 429 static inline void free_part_info(struct hd_struct *part)
 430 {
 431         kfree(part->info);
 432 }
 433
 434 void update_io_ticks(struct hd_struct *part, unsigned long now);
 435
 436 /* block/genhd.c */
 437 extern void device_add_disk(struct device *parent, struct gendisk *disk,
 438                             const struct attribute_group **groups);
 439 static inline void add_disk(struct gendisk *disk)
 440 {
 441         device_add_disk(NULL, disk, NULL);
 442 }
 443 extern void device_add_disk_no_queue_reg(struct device *parent, struct gendisk *disk);
 444 static inline void add_disk_no_queue_reg(struct gendisk *disk)
 445 {
 446         device_add_disk_no_queue_reg(NULL, disk);
 447 }
 448
 449 extern void del_gendisk(struct gendisk *gp);
 450 extern struct gendisk *get_gendisk(dev_t dev, int *partno);
 451 extern struct block_device *bdget_disk(struct gendisk *disk, int partno);
 452
 453 extern void set_device_ro(struct block_device *bdev, int flag);
 454 extern void set_disk_ro(struct gendisk *disk, int flag);
 455
 456 static inline int get_disk_ro(struct gendisk *disk)
 457 {
 458         return disk->part0.policy;
 459 }
 460
 461 extern void disk_block_events(struct gendisk *disk);
 462 extern void disk_unblock_events(struct gendisk *disk);
 463 extern void disk_flush_events(struct gendisk *disk, unsigned int mask);
 464 extern unsigned int disk_clear_events(struct gendisk *disk, unsigned int mask);
 465
 466 /* drivers/char/random.c */
 467 extern void add_disk_randomness(struct gendisk *disk) __latent_entropy;
 468 extern void rand_initialize_disk(struct gendisk *disk);
 469
 470 static inline sector_t get_start_sect(struct block_device *bdev)
 471 {
 472         return bdev->bd_part->start_sect;
 473 }
 474 static inline sector_t get_capacity(struct gendisk *disk)
 475 {
 476         return disk->part0.nr_sects;
 477 }
 478 static inline void set_capacity(struct gendisk *disk, sector_t size)
 479 {
 480         disk->part0.nr_sects = size;
 481 }
 482
 483 #ifdef CONFIG_SOLARIS_X86_PARTITION
 484
 485 #define SOLARIS_X86_NUMSLICE    16
 486 #define SOLARIS_X86_VTOC_SANE   (0x600DDEEEUL)
 487
 488 struct solaris_x86_slice {
 489         __le16 s_tag;           /* ID tag of partition */
 490         __le16 s_flag;          /* permission flags */
 491         __le32 s_start;         /* start sector no of partition */
 492         __le32 s_size;          /* # of blocks in partition */
 493 };
 494
 495 struct solaris_x86_vtoc {
 496         unsigned int v_bootinfo[3];     /* info needed by mboot (unsupported) */
 497         __le32 v_sanity;                /* to verify vtoc sanity */
 498         __le32 v_version;               /* layout version */
 499         char    v_volume[8];            /* volume name */
 500         __le16  v_sectorsz;             /* sector size in bytes */
 501         __le16  v_nparts;               /* number of partitions */
 502         unsigned int v_reserved[10];    /* free space */
 503         struct solaris_x86_slice
 504                 v_slice[SOLARIS_X86_NUMSLICE]; /* slice headers */
 505         unsigned int timestamp[SOLARIS_X86_NUMSLICE]; /* timestamp (unsupported) */
 506         char    v_asciilabel[128];      /* for compatibility */
 507 };
 508
 509 #endif /* CONFIG_SOLARIS_X86_PARTITION */
 510
 511 #ifdef CONFIG_BSD_DISKLABEL
 512 /*
 513  * BSD disklabel support by Yossi Gottlieb <yogo@math.tau.ac.il>
 514  * updated by Marc Espie <Marc.Espie@openbsd.org>
 515  */
 516
 517 /* check against BSD src/sys/sys/disklabel.h for consistency */
 518
 519 #define BSD_DISKMAGIC   (0x82564557UL)  /* The disk magic number */
 520 #define BSD_MAXPARTITIONS       16
 521 #define OPENBSD_MAXPARTITIONS   16
 522 #define BSD_FS_UNUSED           0       /* disklabel unused partition entry ID */
 523 struct bsd_disklabel {
 524         __le32  d_magic;                /* the magic number */
 525         __s16   d_type;                 /* drive type */
 526         __s16   d_subtype;              /* controller/d_type specific */
 527         char    d_typename[16];         /* type name, e.g. "eagle" */
 528         char    d_packname[16];                 /* pack identifier */
 529         __u32   d_secsize;              /* # of bytes per sector */
 530         __u32   d_nsectors;             /* # of data sectors per track */
 531         __u32   d_ntracks;              /* # of tracks per cylinder */
 532         __u32   d_ncylinders;           /* # of data cylinders per unit */
 533         __u32   d_secpercyl;            /* # of data sectors per cylinder */
 534         __u32   d_secperunit;           /* # of data sectors per unit */
 535         __u16   d_sparespertrack;       /* # of spare sectors per track */
 536         __u16   d_sparespercyl;         /* # of spare sectors per cylinder */
 537         __u32   d_acylinders;           /* # of alt. cylinders per unit */
 538         __u16   d_rpm;                  /* rotational speed */
 539         __u16   d_interleave;           /* hardware sector interleave */
 540         __u16   d_trackskew;            /* sector 0 skew, per track */
 541         __u16   d_cylskew;              /* sector 0 skew, per cylinder */
 542         __u32   d_headswitch;           /* head switch time, usec */
 543         __u32   d_trkseek;              /* track-to-track seek, usec */
 544         __u32   d_flags;                /* generic flags */
 545 #define NDDATA 5
 546         __u32   d_drivedata[NDDATA];    /* drive-type specific information */
 547 #define NSPARE 5
 548         __u32   d_spare[NSPARE];        /* reserved for future use */
 549         __le32  d_magic2;               /* the magic number (again) */
 550         __le16  d_checksum;             /* xor of data incl. partitions */
 551
 552                         /* filesystem and partition information: */
 553         __le16  d_npartitions;          /* number of partitions in following */
 554         __le32  d_bbsize;               /* size of boot area at sn0, bytes */
 555         __le32  d_sbsize;               /* max size of fs superblock, bytes */
 556         struct  bsd_partition {         /* the partition table */
 557                 __le32  p_size;         /* number of sectors in partition */
 558                 __le32  p_offset;       /* starting sector */
 559                 __le32  p_fsize;        /* filesystem basic fragment size */
 560                 __u8    p_fstype;       /* filesystem type, see below */
 561                 __u8    p_frag;         /* filesystem fragments per block */
 562                 __le16  p_cpg;          /* filesystem cylinders per group */
 563         } d_partitions[BSD_MAXPARTITIONS];      /* actually may be more */
 564 };
 565
 566 #endif  /* CONFIG_BSD_DISKLABEL */
 567
 568 #ifdef CONFIG_UNIXWARE_DISKLABEL
 569 /*
 570  * Unixware slices support by Andrzej Krzysztofowicz <ankry@mif.pg.gda.pl>
 571  * and Krzysztof G. Baranowski <kgb@knm.org.pl>
 572  */
 573
 574 #define UNIXWARE_DISKMAGIC     (0xCA5E600DUL)   /* The disk magic number */
 575 #define UNIXWARE_DISKMAGIC2    (0x600DDEEEUL)   /* The slice table magic nr */
 576 #define UNIXWARE_NUMSLICE      16
 577 #define UNIXWARE_FS_UNUSED     0                /* Unused slice entry ID */
 578
 579 struct unixware_slice {
 580         __le16   s_label;       /* label */
 581         __le16   s_flags;       /* permission flags */
 582         __le32   start_sect;    /* starting sector */
 583         __le32   nr_sects;      /* number of sectors in slice */
 584 };
 585
 586 struct unixware_disklabel {
 587         __le32   d_type;                /* drive type */
 588         __le32   d_magic;                /* the magic number */
 589         __le32   d_version;              /* version number */
 590         char    d_serial[12];           /* serial number of the device */
 591         __le32   d_ncylinders;           /* # of data cylinders per device */
 592         __le32   d_ntracks;              /* # of tracks per cylinder */
 593         __le32   d_nsectors;             /* # of data sectors per track */
 594         __le32   d_secsize;              /* # of bytes per sector */
 595         __le32   d_part_start;           /* # of first sector of this partition */
 596         __le32   d_unknown1[12];         /* ? */
 597         __le32  d_alt_tbl;              /* byte offset of alternate table */
 598         __le32  d_alt_len;              /* byte length of alternate table */
 599         __le32  d_phys_cyl;             /* # of physical cylinders per device */
 600         __le32  d_phys_trk;             /* # of physical tracks per cylinder */
 601         __le32  d_phys_sec;             /* # of physical sectors per track */
 602         __le32  d_phys_bytes;           /* # of physical bytes per sector */
 603         __le32  d_unknown2;             /* ? */
 604         __le32   d_unknown3;             /* ? */
 605         __le32  d_pad[8];               /* pad */
 606
 607         struct unixware_vtoc {
 608                 __le32  v_magic;                /* the magic number */
 609                 __le32  v_version;              /* version number */
 610                 char    v_name[8];              /* volume name */
 611                 __le16  v_nslices;              /* # of slices */
 612                 __le16  v_unknown1;             /* ? */
 613                 __le32  v_reserved[10];         /* reserved */
 614                 struct unixware_slice
 615                         v_slice[UNIXWARE_NUMSLICE];     /* slice headers */
 616         } vtoc;
 617
 618 };  /* 408 */
 619
 620 #endif /* CONFIG_UNIXWARE_DISKLABEL */
 621
 622 #ifdef CONFIG_MINIX_SUBPARTITION
 623 #   define MINIX_NR_SUBPARTITIONS  4
 624 #endif /* CONFIG_MINIX_SUBPARTITION */
 625
 626 #define ADDPART_FLAG_NONE       0
 627 #define ADDPART_FLAG_RAID       1
 628 #define ADDPART_FLAG_WHOLEDISK  2
 629
 630 extern int blk_alloc_devt(struct hd_struct *part, dev_t *devt);
 631 extern void blk_free_devt(dev_t devt);
 632 extern void blk_invalidate_devt(dev_t devt);
 633 extern dev_t blk_lookup_devt(const char *name, int partno);
 634 extern char *disk_name (struct gendisk *hd, int partno, char *buf);
 635
 636 int bdev_disk_changed(struct block_device *bdev, bool invalidate);
 637 int blk_add_partitions(struct gendisk *disk, struct block_device *bdev);
 638 int blk_drop_partitions(struct gendisk *disk, struct block_device *bdev);
 639 extern int disk_expand_part_tbl(struct gendisk *disk, int target);
 640 extern struct hd_struct * __must_check add_partition(struct gendisk *disk,
 641                                                      int partno, sector_t start,
 642                                                      sector_t len, int flags,
 643                                                      struct partition_meta_info
 644                                                        *info);
 645 extern void __delete_partition(struct percpu_ref *);
 646 extern void delete_partition(struct gendisk *, int);
 647 extern void printk_all_partitions(void);
 648
 649 extern struct gendisk *__alloc_disk_node(int minors, int node_id);
 650 extern struct kobject *get_disk_and_module(struct gendisk *disk);
 651 extern void put_disk(struct gendisk *disk);
 652 extern void put_disk_and_module(struct gendisk *disk);
 653 extern void blk_register_region(dev_t devt, unsigned long range,
 654                         struct module *module,
 655                         struct kobject *(*probe)(dev_t, int *, void *),
 656                         int (*lock)(dev_t, void *),
 657                         void *data);
 658 extern void blk_unregister_region(dev_t devt, unsigned long range);
 659
 660 extern ssize_t part_size_show(struct device *dev,
 661                               struct device_attribute *attr, char *buf);
 662 extern ssize_t part_stat_show(struct device *dev,
 663                               struct device_attribute *attr, char *buf);
 664 extern ssize_t part_inflight_show(struct device *dev,
 665                               struct device_attribute *attr, char *buf);
 666 #ifdef CONFIG_FAIL_MAKE_REQUEST
 667 extern ssize_t part_fail_show(struct device *dev,
 668                               struct device_attribute *attr, char *buf);
 669 extern ssize_t part_fail_store(struct device *dev,
 670                                struct device_attribute *attr,
 671                                const char *buf, size_t count);
 672 #endif /* CONFIG_FAIL_MAKE_REQUEST */
 673
 674 #define alloc_disk_node(minors, node_id)                                \
 675 ({                                                                      \
 676         static struct lock_class_key __key;                             \
 677         const char *__name;                                             \
 678         struct gendisk *__disk;                                         \
 679                                                                         \
 680         __name = "(gendisk_completion)"#minors"("#node_id")";           \
 681                                                                         \
 682         __disk = __alloc_disk_node(minors, node_id);                    \
 683                                                                         \
 684         if (__disk)                                                     \
 685                 lockdep_init_map(&__disk->lockdep_map, __name, &__key, 0); \
 686                                                                         \
 687         __disk;                                                         \
 688 })
 689
 690 #define alloc_disk(minors) alloc_disk_node(minors, NUMA_NO_NODE)
 691
 692 static inline int hd_ref_init(struct hd_struct *part)
 693 {
 694         if (percpu_ref_init(&part->ref, __delete_partition, 0,
 695                                 GFP_KERNEL))
 696                 return -ENOMEM;
 697         return 0;
 698 }
 699
 700 static inline void hd_struct_get(struct hd_struct *part)
 701 {
 702         percpu_ref_get(&part->ref);
 703 }
 704
 705 static inline int hd_struct_try_get(struct hd_struct *part)
 706 {
 707         return percpu_ref_tryget_live(&part->ref);
 708 }
 709
 710 static inline void hd_struct_put(struct hd_struct *part)
 711 {
 712         percpu_ref_put(&part->ref);
 713 }
 714
 715 static inline void hd_struct_kill(struct hd_struct *part)
 716 {
 717         percpu_ref_kill(&part->ref);
 718 }
 719
 720 static inline void hd_free_part(struct hd_struct *part)
 721 {
 722         free_part_stats(part);
 723         free_part_info(part);
 724         percpu_ref_exit(&part->ref);
 725 }
 726
 727 /*
 728  * Any access of part->nr_sects which is not protected by partition
 729  * bd_mutex or gendisk bdev bd_mutex, should be done using this
 730  * accessor function.
 731  *
 732  * Code written along the lines of i_size_read() and i_size_write().
 733  * CONFIG_PREEMPTION case optimizes the case of UP kernel with preemption
 734  * on.
 735  */
 736 static inline sector_t part_nr_sects_read(struct hd_struct *part)
 737 {
 738 #if BITS_PER_LONG==32 && defined(CONFIG_SMP)
 739         sector_t nr_sects;
 740         unsigned seq;
 741         do {
 742                 seq = read_seqcount_begin(&part->nr_sects_seq);
 743                 nr_sects = part->nr_sects;
 744         } while (read_seqcount_retry(&part->nr_sects_seq, seq));
 745         return nr_sects;
 746 #elif BITS_PER_LONG==32 && defined(CONFIG_PREEMPTION)
 747         sector_t nr_sects;
 748
 749         preempt_disable();
 750         nr_sects = part->nr_sects;
 751         preempt_enable();
 752         return nr_sects;
 753 #else
 754         return part->nr_sects;
 755 #endif
 756 }
 757
 758 /*
 759  * Should be called with mutex lock held (typically bd_mutex) of partition
 760  * to provide mutual exlusion among writers otherwise seqcount might be
 761  * left in wrong state leaving the readers spinning infinitely.
 762  */
 763 static inline void part_nr_sects_write(struct hd_struct *part, sector_t size)
 764 {
 765 #if BITS_PER_LONG==32 && defined(CONFIG_SMP)
 766         write_seqcount_begin(&part->nr_sects_seq);
 767         part->nr_sects = size;
 768         write_seqcount_end(&part->nr_sects_seq);
 769 #elif BITS_PER_LONG==32 && defined(CONFIG_PREEMPTION)
 770         preempt_disable();
 771         part->nr_sects = size;
 772         preempt_enable();
 773 #else
 774         part->nr_sects = size;
 775 #endif
 776 }
 777
 778 #if defined(CONFIG_BLK_DEV_INTEGRITY)
 779 extern void blk_integrity_add(struct gendisk *);
 780 extern void blk_integrity_del(struct gendisk *);
 781 #else   /* CONFIG_BLK_DEV_INTEGRITY */
 782 static inline void blk_integrity_add(struct gendisk *disk) { }
 783 static inline void blk_integrity_del(struct gendisk *disk) { }
 784 #endif  /* CONFIG_BLK_DEV_INTEGRITY */
 785
 786 #else /* CONFIG_BLOCK */
 787
 788 static inline void printk_all_partitions(void) { }
 789
 790 static inline dev_t blk_lookup_devt(const char *name, int partno)
 791 {
 792         dev_t devt = MKDEV(0, 0);
 793         return devt;
 794 }
 795 #endif /* CONFIG_BLOCK */
 796
 797 #endif /* _LINUX_GENHD_H */