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         NEW_SOLARIS_X86_PARTITION = 0xbf,
  32
  33         DM6_AUX1PARTITION = 0x51,       /* no DDO:  use xlated geom */
  34         DM6_AUX3PARTITION = 0x53,       /* no DDO:  use xlated geom */
  35         DM6_PARTITION = 0x54,           /* has DDO: use xlated geom & offset */
  36         EZD_PARTITION = 0x55,           /* EZ-DRIVE */
  37
  38         FREEBSD_PARTITION = 0xa5,       /* FreeBSD Partition ID */
  39         OPENBSD_PARTITION = 0xa6,       /* OpenBSD Partition ID */
  40         NETBSD_PARTITION = 0xa9,        /* NetBSD Partition ID */
  41         BSDI_PARTITION = 0xb7,          /* BSDI Partition ID */
  42         MINIX_PARTITION = 0x81,         /* Minix Partition ID */
  43         UNIXWARE_PARTITION = 0x63,      /* Same as GNU_HURD and SCO Unix */
  44 };
  45
  46 #ifndef __KERNEL__
  47
  48 struct partition {
  49         unsigned char boot_ind;         /* 0x80 - active */
  50         unsigned char head;             /* starting head */
  51         unsigned char sector;           /* starting sector */
  52         unsigned char cyl;              /* starting cylinder */
  53         unsigned char sys_ind;          /* What partition type */
  54         unsigned char end_head;         /* end head */
  55         unsigned char end_sector;       /* end sector */
  56         unsigned char end_cyl;          /* end cylinder */
  57         unsigned int start_sect;        /* starting sector counting from 0 */
  58         unsigned int nr_sects;          /* nr of sectors in partition */
  59 } __attribute__((packed));
  60
  61 #endif
  62
  63 #ifdef __KERNEL__
  64 struct partition {
  65         unsigned char boot_ind;         /* 0x80 - active */
  66         unsigned char head;             /* starting head */
  67         unsigned char sector;           /* starting sector */
  68         unsigned char cyl;              /* starting cylinder */
  69         unsigned char sys_ind;          /* What partition type */
  70         unsigned char end_head;         /* end head */
  71         unsigned char end_sector;       /* end sector */
  72         unsigned char end_cyl;          /* end cylinder */
  73         __le32 start_sect;      /* starting sector counting from 0 */
  74         __le32 nr_sects;                /* nr of sectors in partition */
  75 } __attribute__((packed));
  76
  77 struct hd_struct {
  78         sector_t start_sect;
  79         sector_t nr_sects;
  80         struct kobject kobj;
  81         unsigned reads, read_sectors, writes, write_sectors;
  82         int policy, partno;
  83 };
  84
  85 #define GENHD_FL_REMOVABLE                      1
  86 #define GENHD_FL_DRIVERFS                       2
  87 #define GENHD_FL_CD                             8
  88 #define GENHD_FL_UP                             16
  89 #define GENHD_FL_SUPPRESS_PARTITION_INFO        32
  90
  91 struct disk_stats {
  92         unsigned read_sectors, write_sectors;
  93         unsigned reads, writes;
  94         unsigned read_merges, write_merges;
  95         unsigned read_ticks, write_ticks;
  96         unsigned io_ticks;
  97         unsigned time_in_queue;
  98 };
  99
 100 struct gendisk {
 101         int major;                      /* major number of driver */
 102         int first_minor;
 103         int minors;                     /* maximum number of minors, =1 for
 104                                          * disks that can't be partitioned. */
 105         char disk_name[32];             /* name of major driver */
 106         struct hd_struct **part;        /* [indexed by minor] */
 107         struct block_device_operations *fops;
 108         struct request_queue *queue;
 109         void *private_data;
 110         sector_t capacity;
 111
 112         int flags;
 113         char devfs_name[64];            /* devfs crap */
 114         int number;                     /* more of the same */
 115         struct device *driverfs_dev;
 116         struct kobject kobj;
 117
 118         struct timer_rand_state *random;
 119         int policy;
 120
 121         atomic_t sync_io;               /* RAID */
 122         unsigned long stamp, stamp_idle;
 123         int in_flight;
 124 #ifdef  CONFIG_SMP
 125         struct disk_stats *dkstats;
 126 #else
 127         struct disk_stats dkstats;
 128 #endif
 129 };
 130
 131 /* Structure for sysfs attributes on block devices */
 132 struct disk_attribute {
 133         struct attribute attr;
 134         ssize_t (*show)(struct gendisk *, char *);
 135 };
 136
 137 /*
 138  * Macros to operate on percpu disk statistics:
 139  *
 140  * The __ variants should only be called in critical sections. The full
 141  * variants disable/enable preemption.
 142  */
 143 #ifdef  CONFIG_SMP
 144 #define __disk_stat_add(gendiskp, field, addnd)         \
 145         (per_cpu_ptr(gendiskp->dkstats, smp_processor_id())->field += addnd)
 146
 147 #define disk_stat_read(gendiskp, field)                                 \
 148 ({                                                                      \
 149         typeof(gendiskp->dkstats->field) res = 0;                       \
 150         int i;                                                          \
 151         for (i=0; i < NR_CPUS; i++) {                                   \
 152                 if (!cpu_possible(i))                                   \
 153                         continue;                                       \
 154                 res += per_cpu_ptr(gendiskp->dkstats, i)->field;        \
 155         }                                                               \
 156         res;                                                            \
 157 })
 158
 159 static inline void disk_stat_set_all(struct gendisk *gendiskp, int value)       {
 160         int i;
 161         for (i=0; i < NR_CPUS; i++) {
 162                 if (cpu_possible(i)) {
 163                         memset(per_cpu_ptr(gendiskp->dkstats, i), value,
 164                                         sizeof (struct disk_stats));
 165                 }
 166         }
 167 }
 168
 169 #else
 170 #define __disk_stat_add(gendiskp, field, addnd) \
 171                                 (gendiskp->dkstats.field += addnd)
 172 #define disk_stat_read(gendiskp, field) (gendiskp->dkstats.field)
 173
 174 static inline void disk_stat_set_all(struct gendisk *gendiskp, int value)       {
 175         memset(&gendiskp->dkstats, value, sizeof (struct disk_stats));
 176 }
 177 #endif
 178
 179 #define disk_stat_add(gendiskp, field, addnd)                   \
 180         do {                                                    \
 181                 preempt_disable();                              \
 182                 __disk_stat_add(gendiskp, field, addnd);        \
 183                 preempt_enable();                               \
 184         } while (0)
 185
 186 #define __disk_stat_dec(gendiskp, field) __disk_stat_add(gendiskp, field, -1)
 187 #define disk_stat_dec(gendiskp, field) disk_stat_add(gendiskp, field, -1)
 188
 189 #define __disk_stat_inc(gendiskp, field) __disk_stat_add(gendiskp, field, 1)
 190 #define disk_stat_inc(gendiskp, field) disk_stat_add(gendiskp, field, 1)
 191
 192 #define __disk_stat_sub(gendiskp, field, subnd) \
 193                 __disk_stat_add(gendiskp, field, -subnd)
 194 #define disk_stat_sub(gendiskp, field, subnd) \
 195                 disk_stat_add(gendiskp, field, -subnd)
 196
 197
 198 /* Inlines to alloc and free disk stats in struct gendisk */
 199 #ifdef  CONFIG_SMP
 200 static inline int init_disk_stats(struct gendisk *disk)
 201 {
 202         disk->dkstats = alloc_percpu(struct disk_stats);
 203         if (!disk->dkstats)
 204                 return 0;
 205         return 1;
 206 }
 207
 208 static inline void free_disk_stats(struct gendisk *disk)
 209 {
 210         free_percpu(disk->dkstats);
 211 }
 212 #else   /* CONFIG_SMP */
 213 static inline int init_disk_stats(struct gendisk *disk)
 214 {
 215         return 1;
 216 }
 217
 218 static inline void free_disk_stats(struct gendisk *disk)
 219 {
 220 }
 221 #endif  /* CONFIG_SMP */
 222
 223 /* drivers/block/ll_rw_blk.c */
 224 extern void disk_round_stats(struct gendisk *disk);
 225
 226 /* drivers/block/genhd.c */
 227 extern int get_blkdev_list(char *, int);
 228 extern void add_disk(struct gendisk *disk);
 229 extern void del_gendisk(struct gendisk *gp);
 230 extern void unlink_gendisk(struct gendisk *gp);
 231 extern struct gendisk *get_gendisk(dev_t dev, int *part);
 232
 233 extern void set_device_ro(struct block_device *bdev, int flag);
 234 extern void set_disk_ro(struct gendisk *disk, int flag);
 235
 236 /* drivers/char/random.c */
 237 extern void add_disk_randomness(struct gendisk *disk);
 238 extern void rand_initialize_disk(struct gendisk *disk);
 239
 240 static inline sector_t get_start_sect(struct block_device *bdev)
 241 {
 242         return bdev->bd_contains == bdev ? 0 : bdev->bd_part->start_sect;
 243 }
 244 static inline sector_t get_capacity(struct gendisk *disk)
 245 {
 246         return disk->capacity;
 247 }
 248 static inline void set_capacity(struct gendisk *disk, sector_t size)
 249 {
 250         disk->capacity = size;
 251 }
 252
 253 #endif  /*  __KERNEL__  */
 254
 255 #ifdef CONFIG_SOLARIS_X86_PARTITION
 256
 257 #define SOLARIS_X86_NUMSLICE    8
 258 #define SOLARIS_X86_VTOC_SANE   (0x600DDEEEUL)
 259
 260 struct solaris_x86_slice {
 261         __le16 s_tag;           /* ID tag of partition */
 262         __le16 s_flag;          /* permission flags */
 263         __le32 s_start;         /* start sector no of partition */
 264         __le32 s_size;          /* # of blocks in partition */
 265 };
 266
 267 struct solaris_x86_vtoc {
 268         unsigned int v_bootinfo[3];     /* info needed by mboot (unsupported) */
 269         __le32 v_sanity;                /* to verify vtoc sanity */
 270         __le32 v_version;               /* layout version */
 271         char    v_volume[8];            /* volume name */
 272         __le16  v_sectorsz;             /* sector size in bytes */
 273         __le16  v_nparts;               /* number of partitions */
 274         unsigned int v_reserved[10];    /* free space */
 275         struct solaris_x86_slice
 276                 v_slice[SOLARIS_X86_NUMSLICE]; /* slice headers */
 277         unsigned int timestamp[SOLARIS_X86_NUMSLICE]; /* timestamp (unsupported) */
 278         char    v_asciilabel[128];      /* for compatibility */
 279 };
 280
 281 #endif /* CONFIG_SOLARIS_X86_PARTITION */
 282
 283 #ifdef CONFIG_BSD_DISKLABEL
 284 /*
 285  * BSD disklabel support by Yossi Gottlieb <yogo@math.tau.ac.il>
 286  * updated by Marc Espie <Marc.Espie@openbsd.org>
 287  */
 288
 289 /* check against BSD src/sys/sys/disklabel.h for consistency */
 290
 291 #define BSD_DISKMAGIC   (0x82564557UL)  /* The disk magic number */
 292 #define BSD_MAXPARTITIONS       16
 293 #define OPENBSD_MAXPARTITIONS   16
 294 #define BSD_FS_UNUSED           0       /* disklabel unused partition entry ID */
 295 struct bsd_disklabel {
 296         __le32  d_magic;                /* the magic number */
 297         __s16   d_type;                 /* drive type */
 298         __s16   d_subtype;              /* controller/d_type specific */
 299         char    d_typename[16];         /* type name, e.g. "eagle" */
 300         char    d_packname[16];                 /* pack identifier */
 301         __u32   d_secsize;              /* # of bytes per sector */
 302         __u32   d_nsectors;             /* # of data sectors per track */
 303         __u32   d_ntracks;              /* # of tracks per cylinder */
 304         __u32   d_ncylinders;           /* # of data cylinders per unit */
 305         __u32   d_secpercyl;            /* # of data sectors per cylinder */
 306         __u32   d_secperunit;           /* # of data sectors per unit */
 307         __u16   d_sparespertrack;       /* # of spare sectors per track */
 308         __u16   d_sparespercyl;         /* # of spare sectors per cylinder */
 309         __u32   d_acylinders;           /* # of alt. cylinders per unit */
 310         __u16   d_rpm;                  /* rotational speed */
 311         __u16   d_interleave;           /* hardware sector interleave */
 312         __u16   d_trackskew;            /* sector 0 skew, per track */
 313         __u16   d_cylskew;              /* sector 0 skew, per cylinder */
 314         __u32   d_headswitch;           /* head switch time, usec */
 315         __u32   d_trkseek;              /* track-to-track seek, usec */
 316         __u32   d_flags;                /* generic flags */
 317 #define NDDATA 5
 318         __u32   d_drivedata[NDDATA];    /* drive-type specific information */
 319 #define NSPARE 5
 320         __u32   d_spare[NSPARE];        /* reserved for future use */
 321         __le32  d_magic2;               /* the magic number (again) */
 322         __le16  d_checksum;             /* xor of data incl. partitions */
 323
 324                         /* filesystem and partition information: */
 325         __le16  d_npartitions;          /* number of partitions in following */
 326         __le32  d_bbsize;               /* size of boot area at sn0, bytes */
 327         __le32  d_sbsize;               /* max size of fs superblock, bytes */
 328         struct  bsd_partition {         /* the partition table */
 329                 __le32  p_size;         /* number of sectors in partition */
 330                 __le32  p_offset;       /* starting sector */
 331                 __le32  p_fsize;        /* filesystem basic fragment size */
 332                 __u8    p_fstype;       /* filesystem type, see below */
 333                 __u8    p_frag;         /* filesystem fragments per block */
 334                 __le16  p_cpg;          /* filesystem cylinders per group */
 335         } d_partitions[BSD_MAXPARTITIONS];      /* actually may be more */
 336 };
 337
 338 #endif  /* CONFIG_BSD_DISKLABEL */
 339
 340 #ifdef CONFIG_UNIXWARE_DISKLABEL
 341 /*
 342  * Unixware slices support by Andrzej Krzysztofowicz <ankry@mif.pg.gda.pl>
 343  * and Krzysztof G. Baranowski <kgb@knm.org.pl>
 344  */
 345
 346 #define UNIXWARE_DISKMAGIC     (0xCA5E600DUL)   /* The disk magic number */
 347 #define UNIXWARE_DISKMAGIC2    (0x600DDEEEUL)   /* The slice table magic nr */
 348 #define UNIXWARE_NUMSLICE      16
 349 #define UNIXWARE_FS_UNUSED     0                /* Unused slice entry ID */
 350
 351 struct unixware_slice {
 352         __le16   s_label;       /* label */
 353         __le16   s_flags;       /* permission flags */
 354         __le32   start_sect;    /* starting sector */
 355         __le32   nr_sects;      /* number of sectors in slice */
 356 };
 357
 358 struct unixware_disklabel {
 359         __le32   d_type;                /* drive type */
 360         __le32   d_magic;                /* the magic number */
 361         __le32   d_version;              /* version number */
 362         char    d_serial[12];           /* serial number of the device */
 363         __le32   d_ncylinders;           /* # of data cylinders per device */
 364         __le32   d_ntracks;              /* # of tracks per cylinder */
 365         __le32   d_nsectors;             /* # of data sectors per track */
 366         __le32   d_secsize;              /* # of bytes per sector */
 367         __le32   d_part_start;           /* # of first sector of this partition */
 368         __le32   d_unknown1[12];         /* ? */
 369         __le32  d_alt_tbl;              /* byte offset of alternate table */
 370         __le32  d_alt_len;              /* byte length of alternate table */
 371         __le32  d_phys_cyl;             /* # of physical cylinders per device */
 372         __le32  d_phys_trk;             /* # of physical tracks per cylinder */
 373         __le32  d_phys_sec;             /* # of physical sectors per track */
 374         __le32  d_phys_bytes;           /* # of physical bytes per sector */
 375         __le32  d_unknown2;             /* ? */
 376         __le32   d_unknown3;             /* ? */
 377         __le32  d_pad[8];               /* pad */
 378
 379         struct unixware_vtoc {
 380                 __le32  v_magic;                /* the magic number */
 381                 __le32  v_version;              /* version number */
 382                 char    v_name[8];              /* volume name */
 383                 __le16  v_nslices;              /* # of slices */
 384                 __le16  v_unknown1;             /* ? */
 385                 __le32  v_reserved[10];         /* reserved */
 386                 struct unixware_slice
 387                         v_slice[UNIXWARE_NUMSLICE];     /* slice headers */
 388         } vtoc;
 389
 390 };  /* 408 */
 391
 392 #endif /* CONFIG_UNIXWARE_DISKLABEL */
 393
 394 #ifdef CONFIG_MINIX_SUBPARTITION
 395 #   define MINIX_NR_SUBPARTITIONS  4
 396 #endif /* CONFIG_MINIX_SUBPARTITION */
 397
 398 #ifdef __KERNEL__
 399
 400 char *disk_name (struct gendisk *hd, int part, char *buf);
 401
 402 extern int rescan_partitions(struct gendisk *disk, struct block_device *bdev);
 403 extern void add_partition(struct gendisk *, int, sector_t, sector_t);
 404 extern void delete_partition(struct gendisk *, int);
 405
 406 extern struct gendisk *alloc_disk_node(int minors, int node_id);
 407 extern struct gendisk *alloc_disk(int minors);
 408 extern struct kobject *get_disk(struct gendisk *disk);
 409 extern void put_disk(struct gendisk *disk);
 410
 411 extern void blk_register_region(dev_t dev, unsigned long range,
 412                         struct module *module,
 413                         struct kobject *(*probe)(dev_t, int *, void *),
 414                         int (*lock)(dev_t, void *),
 415                         void *data);
 416 extern void blk_unregister_region(dev_t dev, unsigned long range);
 417
 418 static inline struct block_device *bdget_disk(struct gendisk *disk, int index)
 419 {
 420         return bdget(MKDEV(disk->major, disk->first_minor) + index);
 421 }
 422
 423 #endif
 424
 425 #endif