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/config.h>
  13 #include <linux/types.h>
  14 #include <linux/major.h>
  15 #include <linux/device.h>
  16 #include <linux/smp.h>
  17 #include <linux/string.h>
  18 #include <linux/fs.h>
  19
  20 enum {
  21 /* These three have identical behaviour; use the second one if DOS FDISK gets
  22    confused about extended/logical partitions starting past cylinder 1023. */
  23         DOS_EXTENDED_PARTITION = 5,
  24         LINUX_EXTENDED_PARTITION = 0x85,
  25         WIN98_EXTENDED_PARTITION = 0x0f,
  26
  27         LINUX_SWAP_PARTITION = 0x82,
  28         LINUX_RAID_PARTITION = 0xfd,    /* autodetect RAID partition */
  29
  30         SOLARIS_X86_PARTITION = LINUX_SWAP_PARTITION,
  31
  32         DM6_AUX1PARTITION = 0x51,       /* no DDO:  use xlated geom */
  33         DM6_AUX3PARTITION = 0x53,       /* no DDO:  use xlated geom */
  34         DM6_PARTITION = 0x54,           /* has DDO: use xlated geom & offset */
  35         EZD_PARTITION = 0x55,           /* EZ-DRIVE */
  36
  37         FREEBSD_PARTITION = 0xa5,       /* FreeBSD Partition ID */
  38         OPENBSD_PARTITION = 0xa6,       /* OpenBSD Partition ID */
  39         NETBSD_PARTITION = 0xa9,        /* NetBSD Partition ID */
  40         BSDI_PARTITION = 0xb7,          /* BSDI Partition ID */
  41         MINIX_PARTITION = 0x81,         /* Minix Partition ID */
  42         UNIXWARE_PARTITION = 0x63,      /* Same as GNU_HURD and SCO Unix */
  43 };
  44
  45 #ifndef __KERNEL__
  46
  47 struct partition {
  48         unsigned char boot_ind;         /* 0x80 - active */
  49         unsigned char head;             /* starting head */
  50         unsigned char sector;           /* starting sector */
  51         unsigned char cyl;              /* starting cylinder */
  52         unsigned char sys_ind;          /* What partition type */
  53         unsigned char end_head;         /* end head */
  54         unsigned char end_sector;       /* end sector */
  55         unsigned char end_cyl;          /* end cylinder */
  56         unsigned int start_sect;        /* starting sector counting from 0 */
  57         unsigned int nr_sects;          /* nr of sectors in partition */
  58 } __attribute__((packed));
  59
  60 #endif
  61
  62 #ifdef __KERNEL__
  63 struct partition {
  64         unsigned char boot_ind;         /* 0x80 - active */
  65         unsigned char head;             /* starting head */
  66         unsigned char sector;           /* starting sector */
  67         unsigned char cyl;              /* starting cylinder */
  68         unsigned char sys_ind;          /* What partition type */
  69         unsigned char end_head;         /* end head */
  70         unsigned char end_sector;       /* end sector */
  71         unsigned char end_cyl;          /* end cylinder */
  72         __le32 start_sect;      /* starting sector counting from 0 */
  73         __le32 nr_sects;                /* nr of sectors in partition */
  74 } __attribute__((packed));
  75
  76 struct hd_struct {
  77         sector_t start_sect;
  78         sector_t nr_sects;
  79         struct kobject kobj;
  80         unsigned reads, read_sectors, writes, write_sectors;
  81         int policy, partno;
  82 };
  83
  84 #define GENHD_FL_REMOVABLE                      1
  85 #define GENHD_FL_DRIVERFS                       2
  86 #define GENHD_FL_CD                             8
  87 #define GENHD_FL_UP                             16
  88 #define GENHD_FL_SUPPRESS_PARTITION_INFO        32
  89
  90 struct disk_stats {
  91         unsigned read_sectors, write_sectors;
  92         unsigned reads, writes;
  93         unsigned read_merges, write_merges;
  94         unsigned read_ticks, write_ticks;
  95         unsigned io_ticks;
  96         unsigned time_in_queue;
  97 };
  98
  99 struct gendisk {
 100         int major;                      /* major number of driver */
 101         int first_minor;
 102         int minors;                     /* maximum number of minors, =1 for
 103                                          * disks that can't be partitioned. */
 104         char disk_name[32];             /* name of major driver */
 105         struct hd_struct **part;        /* [indexed by minor] */
 106         struct block_device_operations *fops;
 107         struct request_queue *queue;
 108         void *private_data;
 109         sector_t capacity;
 110
 111         int flags;
 112         char devfs_name[64];            /* devfs crap */
 113         int number;                     /* more of the same */
 114         struct device *driverfs_dev;
 115         struct kobject kobj;
 116
 117         struct timer_rand_state *random;
 118         int policy;
 119
 120         atomic_t sync_io;               /* RAID */
 121         unsigned long stamp, stamp_idle;
 122         int in_flight;
 123 #ifdef  CONFIG_SMP
 124         struct disk_stats *dkstats;
 125 #else
 126         struct disk_stats dkstats;
 127 #endif
 128 };
 129
 130 /*
 131  * Macros to operate on percpu disk statistics:
 132  * Since writes to disk_stats are serialised through the queue_lock,
 133  * smp_processor_id() should be enough to get to the per_cpu versions
 134  * of statistics counters
 135  */
 136 #ifdef  CONFIG_SMP
 137 #define disk_stat_add(gendiskp, field, addnd)   \
 138         (per_cpu_ptr(gendiskp->dkstats, smp_processor_id())->field += addnd)
 139 #define disk_stat_read(gendiskp, field)                                 \
 140 ({                                                                      \
 141         typeof(gendiskp->dkstats->field) res = 0;                       \
 142         int i;                                                          \
 143         for (i=0; i < NR_CPUS; i++) {                                   \
 144                 if (!cpu_possible(i))                                   \
 145                         continue;                                       \
 146                 res += per_cpu_ptr(gendiskp->dkstats, i)->field;        \
 147         }                                                               \
 148         res;                                                            \
 149 })
 150
 151 static inline void disk_stat_set_all(struct gendisk *gendiskp, int value)       {
 152         int i;
 153         for (i=0; i < NR_CPUS; i++) {
 154                 if (cpu_possible(i)) {
 155                         memset(per_cpu_ptr(gendiskp->dkstats, i), value,
 156                                         sizeof (struct disk_stats));
 157                 }
 158         }
 159 }
 160
 161 #else
 162 #define disk_stat_add(gendiskp, field, addnd) (gendiskp->dkstats.field += addnd)
 163 #define disk_stat_read(gendiskp, field) (gendiskp->dkstats.field)
 164
 165 static inline void disk_stat_set_all(struct gendisk *gendiskp, int value)       {
 166         memset(&gendiskp->dkstats, value, sizeof (struct disk_stats));
 167 }
 168 #endif
 169
 170 #define disk_stat_inc(gendiskp, field) disk_stat_add(gendiskp, field, 1)
 171 #define disk_stat_dec(gendiskp, field) disk_stat_add(gendiskp, field, -1)
 172 #define disk_stat_sub(gendiskp, field, subnd) \
 173                 disk_stat_add(gendiskp, field, -subnd)
 174
 175
 176 /* Inlines to alloc and free disk stats in struct gendisk */
 177 #ifdef  CONFIG_SMP
 178 static inline int init_disk_stats(struct gendisk *disk)
 179 {
 180         disk->dkstats = alloc_percpu(struct disk_stats);
 181         if (!disk->dkstats)
 182                 return 0;
 183         return 1;
 184 }
 185
 186 static inline void free_disk_stats(struct gendisk *disk)
 187 {
 188         free_percpu(disk->dkstats);
 189 }
 190 #else   /* CONFIG_SMP */
 191 static inline int init_disk_stats(struct gendisk *disk)
 192 {
 193         return 1;
 194 }
 195
 196 static inline void free_disk_stats(struct gendisk *disk)
 197 {
 198 }
 199 #endif  /* CONFIG_SMP */
 200
 201 /* drivers/block/ll_rw_blk.c */
 202 extern void disk_round_stats(struct gendisk *disk);
 203
 204 /* drivers/block/genhd.c */
 205 extern void add_disk(struct gendisk *disk);
 206 extern void del_gendisk(struct gendisk *gp);
 207 extern void unlink_gendisk(struct gendisk *gp);
 208 extern struct gendisk *get_gendisk(dev_t dev, int *part);
 209
 210 extern void set_device_ro(struct block_device *bdev, int flag);
 211 extern void set_disk_ro(struct gendisk *disk, int flag);
 212
 213 /* drivers/char/random.c */
 214 extern void add_disk_randomness(struct gendisk *disk);
 215 extern void rand_initialize_disk(struct gendisk *disk);
 216
 217 static inline sector_t get_start_sect(struct block_device *bdev)
 218 {
 219         return bdev->bd_contains == bdev ? 0 : bdev->bd_part->start_sect;
 220 }
 221 static inline sector_t get_capacity(struct gendisk *disk)
 222 {
 223         return disk->capacity;
 224 }
 225 static inline void set_capacity(struct gendisk *disk, sector_t size)
 226 {
 227         disk->capacity = size;
 228 }
 229
 230 #endif  /*  __KERNEL__  */
 231
 232 #ifdef CONFIG_SOLARIS_X86_PARTITION
 233
 234 #define SOLARIS_X86_NUMSLICE    8
 235 #define SOLARIS_X86_VTOC_SANE   (0x600DDEEEUL)
 236
 237 struct solaris_x86_slice {
 238         __le16 s_tag;           /* ID tag of partition */
 239         __le16 s_flag;          /* permission flags */
 240         __le32 s_start;         /* start sector no of partition */
 241         __le32 s_size;          /* # of blocks in partition */
 242 };
 243
 244 struct solaris_x86_vtoc {
 245         unsigned int v_bootinfo[3];     /* info needed by mboot (unsupported) */
 246         __le32 v_sanity;                /* to verify vtoc sanity */
 247         __le32 v_version;               /* layout version */
 248         char    v_volume[8];            /* volume name */
 249         __le16  v_sectorsz;             /* sector size in bytes */
 250         __le16  v_nparts;               /* number of partitions */
 251         unsigned int v_reserved[10];    /* free space */
 252         struct solaris_x86_slice
 253                 v_slice[SOLARIS_X86_NUMSLICE]; /* slice headers */
 254         unsigned int timestamp[SOLARIS_X86_NUMSLICE]; /* timestamp (unsupported) */
 255         char    v_asciilabel[128];      /* for compatibility */
 256 };
 257
 258 #endif /* CONFIG_SOLARIS_X86_PARTITION */
 259
 260 #ifdef CONFIG_BSD_DISKLABEL
 261 /*
 262  * BSD disklabel support by Yossi Gottlieb <yogo@math.tau.ac.il>
 263  * updated by Marc Espie <Marc.Espie@openbsd.org>
 264  */
 265
 266 /* check against BSD src/sys/sys/disklabel.h for consistency */
 267
 268 #define BSD_DISKMAGIC   (0x82564557UL)  /* The disk magic number */
 269 #define BSD_MAXPARTITIONS       16
 270 #define OPENBSD_MAXPARTITIONS   16
 271 #define BSD_FS_UNUSED           0       /* disklabel unused partition entry ID */
 272 struct bsd_disklabel {
 273         __le32  d_magic;                /* the magic number */
 274         __s16   d_type;                 /* drive type */
 275         __s16   d_subtype;              /* controller/d_type specific */
 276         char    d_typename[16];         /* type name, e.g. "eagle" */
 277         char    d_packname[16];                 /* pack identifier */
 278         __u32   d_secsize;              /* # of bytes per sector */
 279         __u32   d_nsectors;             /* # of data sectors per track */
 280         __u32   d_ntracks;              /* # of tracks per cylinder */
 281         __u32   d_ncylinders;           /* # of data cylinders per unit */
 282         __u32   d_secpercyl;            /* # of data sectors per cylinder */
 283         __u32   d_secperunit;           /* # of data sectors per unit */
 284         __u16   d_sparespertrack;       /* # of spare sectors per track */
 285         __u16   d_sparespercyl;         /* # of spare sectors per cylinder */
 286         __u32   d_acylinders;           /* # of alt. cylinders per unit */
 287         __u16   d_rpm;                  /* rotational speed */
 288         __u16   d_interleave;           /* hardware sector interleave */
 289         __u16   d_trackskew;            /* sector 0 skew, per track */
 290         __u16   d_cylskew;              /* sector 0 skew, per cylinder */
 291         __u32   d_headswitch;           /* head switch time, usec */
 292         __u32   d_trkseek;              /* track-to-track seek, usec */
 293         __u32   d_flags;                /* generic flags */
 294 #define NDDATA 5
 295         __u32   d_drivedata[NDDATA];    /* drive-type specific information */
 296 #define NSPARE 5
 297         __u32   d_spare[NSPARE];        /* reserved for future use */
 298         __le32  d_magic2;               /* the magic number (again) */
 299         __le16  d_checksum;             /* xor of data incl. partitions */
 300
 301                         /* filesystem and partition information: */
 302         __le16  d_npartitions;          /* number of partitions in following */
 303         __le32  d_bbsize;               /* size of boot area at sn0, bytes */
 304         __le32  d_sbsize;               /* max size of fs superblock, bytes */
 305         struct  bsd_partition {         /* the partition table */
 306                 __le32  p_size;         /* number of sectors in partition */
 307                 __le32  p_offset;       /* starting sector */
 308                 __le32  p_fsize;        /* filesystem basic fragment size */
 309                 __u8    p_fstype;       /* filesystem type, see below */
 310                 __u8    p_frag;         /* filesystem fragments per block */
 311                 __le16  p_cpg;          /* filesystem cylinders per group */
 312         } d_partitions[BSD_MAXPARTITIONS];      /* actually may be more */
 313 };
 314
 315 #endif  /* CONFIG_BSD_DISKLABEL */
 316
 317 #ifdef CONFIG_UNIXWARE_DISKLABEL
 318 /*
 319  * Unixware slices support by Andrzej Krzysztofowicz <ankry@mif.pg.gda.pl>
 320  * and Krzysztof G. Baranowski <kgb@knm.org.pl>
 321  */
 322
 323 #define UNIXWARE_DISKMAGIC     (0xCA5E600DUL)   /* The disk magic number */
 324 #define UNIXWARE_DISKMAGIC2    (0x600DDEEEUL)   /* The slice table magic nr */
 325 #define UNIXWARE_NUMSLICE      16
 326 #define UNIXWARE_FS_UNUSED     0                /* Unused slice entry ID */
 327
 328 struct unixware_slice {
 329         __le16   s_label;       /* label */
 330         __le16   s_flags;       /* permission flags */
 331         __le32   start_sect;    /* starting sector */
 332         __le32   nr_sects;      /* number of sectors in slice */
 333 };
 334
 335 struct unixware_disklabel {
 336         __le32   d_type;                /* drive type */
 337         __le32   d_magic;                /* the magic number */
 338         __le32   d_version;              /* version number */
 339         char    d_serial[12];           /* serial number of the device */
 340         __le32   d_ncylinders;           /* # of data cylinders per device */
 341         __le32   d_ntracks;              /* # of tracks per cylinder */
 342         __le32   d_nsectors;             /* # of data sectors per track */
 343         __le32   d_secsize;              /* # of bytes per sector */
 344         __le32   d_part_start;           /* # of first sector of this partition */
 345         __le32   d_unknown1[12];         /* ? */
 346         __le32  d_alt_tbl;              /* byte offset of alternate table */
 347         __le32  d_alt_len;              /* byte length of alternate table */
 348         __le32  d_phys_cyl;             /* # of physical cylinders per device */
 349         __le32  d_phys_trk;             /* # of physical tracks per cylinder */
 350         __le32  d_phys_sec;             /* # of physical sectors per track */
 351         __le32  d_phys_bytes;           /* # of physical bytes per sector */
 352         __le32  d_unknown2;             /* ? */
 353         __le32   d_unknown3;             /* ? */
 354         __le32  d_pad[8];               /* pad */
 355
 356         struct unixware_vtoc {
 357                 __le32  v_magic;                /* the magic number */
 358                 __le32  v_version;              /* version number */
 359                 char    v_name[8];              /* volume name */
 360                 __le16  v_nslices;              /* # of slices */
 361                 __le16  v_unknown1;             /* ? */
 362                 __le32  v_reserved[10];         /* reserved */
 363                 struct unixware_slice
 364                         v_slice[UNIXWARE_NUMSLICE];     /* slice headers */
 365         } vtoc;
 366
 367 };  /* 408 */
 368
 369 #endif /* CONFIG_UNIXWARE_DISKLABEL */
 370
 371 #ifdef CONFIG_MINIX_SUBPARTITION
 372 #   define MINIX_NR_SUBPARTITIONS  4
 373 #endif /* CONFIG_MINIX_SUBPARTITION */
 374
 375 #ifdef __KERNEL__
 376
 377 char *disk_name (struct gendisk *hd, int part, char *buf);
 378
 379 extern int rescan_partitions(struct gendisk *disk, struct block_device *bdev);
 380 extern void add_partition(struct gendisk *, int, sector_t, sector_t);
 381 extern void delete_partition(struct gendisk *, int);
 382
 383 extern struct gendisk *alloc_disk(int minors);
 384 extern struct kobject *get_disk(struct gendisk *disk);
 385 extern void put_disk(struct gendisk *disk);
 386
 387 extern void blk_register_region(dev_t dev, unsigned long range,
 388                         struct module *module,
 389                         struct kobject *(*probe)(dev_t, int *, void *),
 390                         int (*lock)(dev_t, void *),
 391                         void *data);
 392 extern void blk_unregister_region(dev_t dev, unsigned long range);
 393
 394 static inline struct block_device *bdget_disk(struct gendisk *disk, int index)
 395 {
 396         return bdget(MKDEV(disk->major, disk->first_minor) + index);
 397 }
 398
 399 #endif
 400
 401 #endif