LXR linux/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
  16#ifdef CONFIG_BLOCK
  17
  18#define kobj_to_dev(k)          container_of((k), struct device, kobj)
  19#define dev_to_disk(device)     container_of((device), struct gendisk, part0.__dev)
  20#define dev_to_part(device)     container_of((device), struct hd_struct, __dev)
  21#define disk_to_dev(disk)       (&(disk)->part0.__dev)
  22#define part_to_dev(part)       (&((part)->__dev))
  23
  24extern struct device_type part_type;
  25extern struct kobject *block_depr;
  26extern struct class block_class;
  27
  28enum {
  29/* These three have identical behaviour; use the second one if DOS FDISK gets
  30   confused about extended/logical partitions starting past cylinder 1023. */
  31        DOS_EXTENDED_PARTITION = 5,
  32        LINUX_EXTENDED_PARTITION = 0x85,
  33        WIN98_EXTENDED_PARTITION = 0x0f,
  34
  35        SUN_WHOLE_DISK = DOS_EXTENDED_PARTITION,
  36
  37        LINUX_SWAP_PARTITION = 0x82,
  38        LINUX_DATA_PARTITION = 0x83,
  39        LINUX_LVM_PARTITION = 0x8e,
  40        LINUX_RAID_PARTITION = 0xfd,    /* autodetect RAID partition */
  41
  42        SOLARIS_X86_PARTITION = LINUX_SWAP_PARTITION,
  43        NEW_SOLARIS_X86_PARTITION = 0xbf,
  44
  45        DM6_AUX1PARTITION = 0x51,       /* no DDO:  use xlated geom */
  46        DM6_AUX3PARTITION = 0x53,       /* no DDO:  use xlated geom */
  47        DM6_PARTITION = 0x54,           /* has DDO: use xlated geom & offset */
  48        EZD_PARTITION = 0x55,           /* EZ-DRIVE */
  49
  50        FREEBSD_PARTITION = 0xa5,       /* FreeBSD Partition ID */
  51        OPENBSD_PARTITION = 0xa6,       /* OpenBSD Partition ID */
  52        NETBSD_PARTITION = 0xa9,        /* NetBSD Partition ID */
  53        BSDI_PARTITION = 0xb7,          /* BSDI Partition ID */
  54        MINIX_PARTITION = 0x81,         /* Minix Partition ID */
  55        UNIXWARE_PARTITION = 0x63,      /* Same as GNU_HURD and SCO Unix */
  56};
  57
  58#define DISK_MAX_PARTS                  256
  59#define DISK_NAME_LEN                   32
  60
  61#include <linux/major.h>
  62#include <linux/device.h>
  63#include <linux/smp.h>
  64#include <linux/string.h>
  65#include <linux/fs.h>
  66#include <linux/workqueue.h>
  67
  68struct partition {
  69        unsigned char boot_ind;         /* 0x80 - active */
  70        unsigned char head;             /* starting head */
  71        unsigned char sector;           /* starting sector */
  72        unsigned char cyl;              /* starting cylinder */
  73        unsigned char sys_ind;          /* What partition type */
  74        unsigned char end_head;         /* end head */
  75        unsigned char end_sector;       /* end sector */
  76        unsigned char end_cyl;          /* end cylinder */
  77        __le32 start_sect;      /* starting sector counting from 0 */
  78        __le32 nr_sects;                /* nr of sectors in partition */
  79} __attribute__((packed));
  80
  81struct disk_stats {
  82        unsigned long sectors[2];       /* READs and WRITEs */
  83        unsigned long ios[2];
  84        unsigned long merges[2];
  85        unsigned long ticks[2];
  86        unsigned long io_ticks;
  87        unsigned long time_in_queue;
  88};
  89        
  90struct hd_struct {
  91        sector_t start_sect;
  92        sector_t nr_sects;
  93        struct device __dev;
  94        struct kobject *holder_dir;
  95        int policy, partno;
  96#ifdef CONFIG_FAIL_MAKE_REQUEST
  97        int make_it_fail;
  98#endif
  99        unsigned long stamp;
 100        int in_flight;
 101#ifdef  CONFIG_SMP
 102        struct disk_stats *dkstats;
 103#else
 104        struct disk_stats dkstats;
 105#endif
 106        struct rcu_head rcu_head;
 107};
 108
 109#define GENHD_FL_REMOVABLE                      1
 110#define GENHD_FL_DRIVERFS                       2
 111#define GENHD_FL_MEDIA_CHANGE_NOTIFY            4
 112#define GENHD_FL_CD                             8
 113#define GENHD_FL_UP                             16
 114#define GENHD_FL_SUPPRESS_PARTITION_INFO        32
 115#define GENHD_FL_EXT_DEVT                       64 /* allow extended devt */
 116
 117#define BLK_SCSI_MAX_CMDS       (256)
 118#define BLK_SCSI_CMD_PER_LONG   (BLK_SCSI_MAX_CMDS / (sizeof(long) * 8))
 119
 120struct blk_scsi_cmd_filter {
 121        unsigned long read_ok[BLK_SCSI_CMD_PER_LONG];
 122        unsigned long write_ok[BLK_SCSI_CMD_PER_LONG];
 123        struct kobject kobj;
 124};
 125
 126struct disk_part_tbl {
 127        struct rcu_head rcu_head;
 128        int len;
 129        struct hd_struct *last_lookup;
 130        struct hd_struct *part[];
 131};
 132
 133struct gendisk {
 134        /* major, first_minor and minors are input parameters only,
 135         * don't use directly.  Use disk_devt() and disk_max_parts().
 136         */
 137        int major;                      /* major number of driver */
 138        int first_minor;
 139        int minors;                     /* maximum number of minors, =1 for
 140                                         * disks that can't be partitioned. */
 141
 142        char disk_name[DISK_NAME_LEN];  /* name of major driver */
 143
 144        /* Array of pointers to partitions indexed by partno.
 145         * Protected with matching bdev lock but stat and other
 146         * non-critical accesses use RCU.  Always access through
 147         * helpers.
 148         */
 149        struct disk_part_tbl *part_tbl;
 150        struct hd_struct part0;
 151
 152        struct block_device_operations *fops;
 153        struct request_queue *queue;
 154        void *private_data;
 155
 156        int flags;
 157        struct device *driverfs_dev;  // FIXME: remove
 158        struct kobject *slave_dir;
 159
 160        struct timer_rand_state *random;
 161
 162        atomic_t sync_io;               /* RAID */
 163        struct work_struct async_notify;
 164#ifdef  CONFIG_BLK_DEV_INTEGRITY
 165        struct blk_integrity *integrity;
 166#endif
 167        int node_id;
 168};
 169
 170static inline struct gendisk *part_to_disk(struct hd_struct *part)
 171{
 172        if (likely(part)) {
 173                if (part->partno)
 174                        return dev_to_disk(part_to_dev(part)->parent);
 175                else
 176                        return dev_to_disk(part_to_dev(part));
 177        }
 178        return NULL;
 179}
 180
 181static inline int disk_max_parts(struct gendisk *disk)
 182{
 183        if (disk->flags & GENHD_FL_EXT_DEVT)
 184                return DISK_MAX_PARTS;
 185        return disk->minors;
 186}
 187
 188static inline bool disk_partitionable(struct gendisk *disk)
 189{
 190        return disk_max_parts(disk) > 1;
 191}
 192
 193static inline dev_t disk_devt(struct gendisk *disk)
 194{
 195        return disk_to_dev(disk)->devt;
 196}
 197
 198static inline dev_t part_devt(struct hd_struct *part)
 199{
 200        return part_to_dev(part)->devt;
 201}
 202
 203extern struct hd_struct *disk_get_part(struct gendisk *disk, int partno);
 204
 205static inline void disk_put_part(struct hd_struct *part)
 206{
 207        if (likely(part))
 208                put_device(part_to_dev(part));
 209}
 210
 211/*
 212 * Smarter partition iterator without context limits.
 213 */
 214#define DISK_PITER_REVERSE      (1 << 0) /* iterate in the reverse direction */
 215#define DISK_PITER_INCL_EMPTY   (1 << 1) /* include 0-sized parts */
 216#define DISK_PITER_INCL_PART0   (1 << 2) /* include partition 0 */
 217
 218struct disk_part_iter {
 219        struct gendisk          *disk;
 220        struct hd_struct        *part;
 221        int                     idx;
 222        unsigned int            flags;
 223};
 224
 225extern void disk_part_iter_init(struct disk_part_iter *piter,
 226                                 struct gendisk *disk, unsigned int flags);
 227extern struct hd_struct *disk_part_iter_next(struct disk_part_iter *piter);
 228extern void disk_part_iter_exit(struct disk_part_iter *piter);
 229
 230extern struct hd_struct *disk_map_sector_rcu(struct gendisk *disk,
 231                                             sector_t sector);
 232
 233/*
 234 * Macros to operate on percpu disk statistics:
 235 *
 236 * {disk|part|all}_stat_{add|sub|inc|dec}() modify the stat counters
 237 * and should be called between disk_stat_lock() and
 238 * disk_stat_unlock().
 239 *
 240 * part_stat_read() can be called at any time.
 241 *
 242 * part_stat_{add|set_all}() and {init|free}_part_stats are for
 243 * internal use only.
 244 */
 245#ifdef  CONFIG_SMP
 246#define part_stat_lock()        ({ rcu_read_lock(); get_cpu(); })
 247#define part_stat_unlock()      do { put_cpu(); rcu_read_unlock(); } while (0)
 248
 249#define __part_stat_add(cpu, part, field, addnd)                        \
 250        (per_cpu_ptr((part)->dkstats, (cpu))->field += (addnd))
 251
 252#define part_stat_read(part, field)                                     \
 253({                                                                      \
 254        typeof((part)->dkstats->field) res = 0;                         \
 255        int i;                                                          \
 256        for_each_possible_cpu(i)                                        \
 257                res += per_cpu_ptr((part)->dkstats, i)->field;          \
 258        res;                                                            \
 259})
 260
 261static inline void part_stat_set_all(struct hd_struct *part, int value)
 262{
 263        int i;
 264
 265        for_each_possible_cpu(i)
 266                memset(per_cpu_ptr(part->dkstats, i), value,
 267                                sizeof(struct disk_stats));
 268}
 269
 270static inline int init_part_stats(struct hd_struct *part)
 271{
 272        part->dkstats = alloc_percpu(struct disk_stats);
 273        if (!part->dkstats)
 274                return 0;
 275        return 1;
 276}
 277
 278static inline void free_part_stats(struct hd_struct *part)
 279{
 280        free_percpu(part->dkstats);
 281}
 282
 283#else /* !CONFIG_SMP */
 284#define part_stat_lock()        ({ rcu_read_lock(); 0; })
 285#define part_stat_unlock()      rcu_read_unlock()
 286
 287#define __part_stat_add(cpu, part, field, addnd)                                \
 288        ((part)->dkstats.field += addnd)
 289
 290#define part_stat_read(part, field)     ((part)->dkstats.field)
 291
 292static inline void part_stat_set_all(struct hd_struct *part, int value)
 293{
 294        memset(&part->dkstats, value, sizeof(struct disk_stats));
 295}
 296
 297static inline int init_part_stats(struct hd_struct *part)
 298{
 299        return 1;
 300}
 301
 302static inline void free_part_stats(struct hd_struct *part)
 303{
 304}
 305
 306#endif /* CONFIG_SMP */
 307
 308#define part_stat_add(cpu, part, field, addnd)  do {                    \
 309        __part_stat_add((cpu), (part), field, addnd);                   \
 310        if ((part)->partno)                                             \
 311                __part_stat_add((cpu), &part_to_disk((part))->part0,    \
 312                                field, addnd);                          \
 313} while (0)
 314
 315#define part_stat_dec(cpu, gendiskp, field)                             \
 316        part_stat_add(cpu, gendiskp, field, -1)
 317#define part_stat_inc(cpu, gendiskp, field)                             \
 318        part_stat_add(cpu, gendiskp, field, 1)
 319#define part_stat_sub(cpu, gendiskp, field, subnd)                      \
 320        part_stat_add(cpu, gendiskp, field, -subnd)
 321
 322static inline void part_inc_in_flight(struct hd_struct *part)
 323{
 324        part->in_flight++;
 325        if (part->partno)
 326                part_to_disk(part)->part0.in_flight++;
 327}
 328
 329static inline void part_dec_in_flight(struct hd_struct *part)
 330{
 331        part->in_flight--;
 332        if (part->partno)
 333                part_to_disk(part)->part0.in_flight--;
 334}
 335
 336/* drivers/block/ll_rw_blk.c */
 337extern void part_round_stats(int cpu, struct hd_struct *part);
 338
 339/* drivers/block/genhd.c */
 340extern int get_blkdev_list(char *, int);
 341extern void add_disk(struct gendisk *disk);
 342extern void del_gendisk(struct gendisk *gp);
 343extern void unlink_gendisk(struct gendisk *gp);
 344extern struct gendisk *get_gendisk(dev_t dev, int *partno);
 345extern struct block_device *bdget_disk(struct gendisk *disk, int partno);
 346
 347extern void set_device_ro(struct block_device *bdev, int flag);
 348extern void set_disk_ro(struct gendisk *disk, int flag);
 349
 350static inline int get_disk_ro(struct gendisk *disk)
 351{
 352        return disk->part0.policy;
 353}
 354
 355/* drivers/char/random.c */
 356extern void add_disk_randomness(struct gendisk *disk);
 357extern void rand_initialize_disk(struct gendisk *disk);
 358
 359static inline sector_t get_start_sect(struct block_device *bdev)
 360{
 361        return bdev->bd_part->start_sect;
 362}
 363static inline sector_t get_capacity(struct gendisk *disk)
 364{
 365        return disk->part0.nr_sects;
 366}
 367static inline void set_capacity(struct gendisk *disk, sector_t size)
 368{
 369        disk->part0.nr_sects = size;
 370}
 371
 372#ifdef CONFIG_SOLARIS_X86_PARTITION
 373
 374#define SOLARIS_X86_NUMSLICE    16
 375#define SOLARIS_X86_VTOC_SANE   (0x600DDEEEUL)
 376
 377struct solaris_x86_slice {
 378        __le16 s_tag;           /* ID tag of partition */
 379        __le16 s_flag;          /* permission flags */
 380        __le32 s_start;         /* start sector no of partition */
 381        __le32 s_size;          /* # of blocks in partition */
 382};
 383
 384struct solaris_x86_vtoc {
 385        unsigned int v_bootinfo[3];     /* info needed by mboot (unsupported) */
 386        __le32 v_sanity;                /* to verify vtoc sanity */
 387        __le32 v_version;               /* layout version */
 388        char    v_volume[8];            /* volume name */
 389        __le16  v_sectorsz;             /* sector size in bytes */
 390        __le16  v_nparts;               /* number of partitions */
 391        unsigned int v_reserved[10];    /* free space */
 392        struct solaris_x86_slice
 393                v_slice[SOLARIS_X86_NUMSLICE]; /* slice headers */
 394        unsigned int timestamp[SOLARIS_X86_NUMSLICE]; /* timestamp (unsupported) */
 395        char    v_asciilabel[128];      /* for compatibility */
 396};
 397
 398#endif /* CONFIG_SOLARIS_X86_PARTITION */
 399
 400#ifdef CONFIG_BSD_DISKLABEL
 401/*
 402 * BSD disklabel support by Yossi Gottlieb <yogo@math.tau.ac.il>
 403 * updated by Marc Espie <Marc.Espie@openbsd.org>
 404 */
 405
 406/* check against BSD src/sys/sys/disklabel.h for consistency */
 407
 408#define BSD_DISKMAGIC   (0x82564557UL)  /* The disk magic number */
 409#define BSD_MAXPARTITIONS       16
 410#define OPENBSD_MAXPARTITIONS   16
 411#define BSD_FS_UNUSED           0       /* disklabel unused partition entry ID */
 412struct bsd_disklabel {
 413        __le32  d_magic;                /* the magic number */
 414        __s16   d_type;                 /* drive type */
 415        __s16   d_subtype;              /* controller/d_type specific */
 416        char    d_typename[16];         /* type name, e.g. "eagle" */
 417        char    d_packname[16];                 /* pack identifier */ 
 418        __u32   d_secsize;              /* # of bytes per sector */
 419        __u32   d_nsectors;             /* # of data sectors per track */
 420        __u32   d_ntracks;              /* # of tracks per cylinder */
 421        __u32   d_ncylinders;           /* # of data cylinders per unit */
 422        __u32   d_secpercyl;            /* # of data sectors per cylinder */
 423        __u32   d_secperunit;           /* # of data sectors per unit */
 424        __u16   d_sparespertrack;       /* # of spare sectors per track */
 425        __u16   d_sparespercyl;         /* # of spare sectors per cylinder */
 426        __u32   d_acylinders;           /* # of alt. cylinders per unit */
 427        __u16   d_rpm;                  /* rotational speed */
 428        __u16   d_interleave;           /* hardware sector interleave */
 429        __u16   d_trackskew;            /* sector 0 skew, per track */
 430        __u16   d_cylskew;              /* sector 0 skew, per cylinder */
 431        __u32   d_headswitch;           /* head switch time, usec */
 432        __u32   d_trkseek;              /* track-to-track seek, usec */
 433        __u32   d_flags;                /* generic flags */
 434#define NDDATA 5
 435        __u32   d_drivedata[NDDATA];    /* drive-type specific information */
 436#define NSPARE 5
 437        __u32   d_spare[NSPARE];        /* reserved for future use */
 438        __le32  d_magic2;               /* the magic number (again) */
 439        __le16  d_checksum;             /* xor of data incl. partitions */
 440
 441                        /* filesystem and partition information: */
 442        __le16  d_npartitions;          /* number of partitions in following */
 443        __le32  d_bbsize;               /* size of boot area at sn0, bytes */
 444        __le32  d_sbsize;               /* max size of fs superblock, bytes */
 445        struct  bsd_partition {         /* the partition table */
 446                __le32  p_size;         /* number of sectors in partition */
 447                __le32  p_offset;       /* starting sector */
 448                __le32  p_fsize;        /* filesystem basic fragment size */
 449                __u8    p_fstype;       /* filesystem type, see below */
 450                __u8    p_frag;         /* filesystem fragments per block */
 451                __le16  p_cpg;          /* filesystem cylinders per group */
 452        } d_partitions[BSD_MAXPARTITIONS];      /* actually may be more */
 453};
 454
 455#endif  /* CONFIG_BSD_DISKLABEL */
 456
 457#ifdef CONFIG_UNIXWARE_DISKLABEL
 458/*
 459 * Unixware slices support by Andrzej Krzysztofowicz <ankry@mif.pg.gda.pl>
 460 * and Krzysztof G. Baranowski <kgb@knm.org.pl>
 461 */
 462
 463#define UNIXWARE_DISKMAGIC     (0xCA5E600DUL)   /* The disk magic number */
 464#define UNIXWARE_DISKMAGIC2    (0x600DDEEEUL)   /* The slice table magic nr */
 465#define UNIXWARE_NUMSLICE      16
 466#define UNIXWARE_FS_UNUSED     0                /* Unused slice entry ID */
 467
 468struct unixware_slice {
 469        __le16   s_label;       /* label */
 470        __le16   s_flags;       /* permission flags */
 471        __le32   start_sect;    /* starting sector */
 472        __le32   nr_sects;      /* number of sectors in slice */
 473};
 474
 475struct unixware_disklabel {
 476        __le32   d_type;                /* drive type */
 477        __le32   d_magic;                /* the magic number */
 478        __le32   d_version;              /* version number */
 479        char    d_serial[12];           /* serial number of the device */
 480        __le32   d_ncylinders;           /* # of data cylinders per device */
 481        __le32   d_ntracks;              /* # of tracks per cylinder */
 482        __le32   d_nsectors;             /* # of data sectors per track */
 483        __le32   d_secsize;              /* # of bytes per sector */
 484        __le32   d_part_start;           /* # of first sector of this partition */
 485        __le32   d_unknown1[12];         /* ? */
 486        __le32  d_alt_tbl;              /* byte offset of alternate table */
 487        __le32  d_alt_len;              /* byte length of alternate table */
 488        __le32  d_phys_cyl;             /* # of physical cylinders per device */
 489        __le32  d_phys_trk;             /* # of physical tracks per cylinder */
 490        __le32  d_phys_sec;             /* # of physical sectors per track */
 491        __le32  d_phys_bytes;           /* # of physical bytes per sector */
 492        __le32  d_unknown2;             /* ? */
 493        __le32   d_unknown3;             /* ? */
 494        __le32  d_pad[8];               /* pad */
 495
 496        struct unixware_vtoc {
 497                __le32  v_magic;                /* the magic number */
 498                __le32  v_version;              /* version number */
 499                char    v_name[8];              /* volume name */
 500                __le16  v_nslices;              /* # of slices */
 501                __le16  v_unknown1;             /* ? */
 502                __le32  v_reserved[10];         /* reserved */
 503                struct unixware_slice
 504                        v_slice[UNIXWARE_NUMSLICE];     /* slice headers */
 505        } vtoc;
 506
 507};  /* 408 */
 508
 509#endif /* CONFIG_UNIXWARE_DISKLABEL */
 510
 511#ifdef CONFIG_MINIX_SUBPARTITION
 512#   define MINIX_NR_SUBPARTITIONS  4
 513#endif /* CONFIG_MINIX_SUBPARTITION */
 514
 515#define ADDPART_FLAG_NONE       0
 516#define ADDPART_FLAG_RAID       1
 517#define ADDPART_FLAG_WHOLEDISK  2
 518
 519extern int blk_alloc_devt(struct hd_struct *part, dev_t *devt);
 520extern void blk_free_devt(dev_t devt);
 521extern dev_t blk_lookup_devt(const char *name, int partno);
 522extern char *disk_name (struct gendisk *hd, int partno, char *buf);
 523
 524extern int disk_expand_part_tbl(struct gendisk *disk, int target);
 525extern int rescan_partitions(struct gendisk *disk, struct block_device *bdev);
 526extern struct hd_struct * __must_check add_partition(struct gendisk *disk,
 527                                                     int partno, sector_t start,
 528                                                     sector_t len, int flags);
 529extern void delete_partition(struct gendisk *, int);
 530extern void printk_all_partitions(void);
 531
 532extern struct gendisk *alloc_disk_node(int minors, int node_id);
 533extern struct gendisk *alloc_disk(int minors);
 534extern struct kobject *get_disk(struct gendisk *disk);
 535extern void put_disk(struct gendisk *disk);
 536extern void blk_register_region(dev_t devt, unsigned long range,
 537                        struct module *module,
 538                        struct kobject *(*probe)(dev_t, int *, void *),
 539                        int (*lock)(dev_t, void *),
 540                        void *data);
 541extern void blk_unregister_region(dev_t devt, unsigned long range);
 542
 543extern ssize_t part_size_show(struct device *dev,
 544                              struct device_attribute *attr, char *buf);
 545extern ssize_t part_stat_show(struct device *dev,
 546                              struct device_attribute *attr, char *buf);
 547#ifdef CONFIG_FAIL_MAKE_REQUEST
 548extern ssize_t part_fail_show(struct device *dev,
 549                              struct device_attribute *attr, char *buf);
 550extern ssize_t part_fail_store(struct device *dev,
 551                               struct device_attribute *attr,
 552                               const char *buf, size_t count);
 553#endif /* CONFIG_FAIL_MAKE_REQUEST */
 554
 555#else /* CONFIG_BLOCK */
 556
 557static inline void printk_all_partitions(void) { }
 558
 559static inline dev_t blk_lookup_devt(const char *name, int partno)
 560{
 561        dev_t devt = MKDEV(0, 0);
 562        return devt;
 563}
 564
 565#endif /* CONFIG_BLOCK */
 566
 567#endif /* _LINUX_GENHD_H */
 568