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
  15 #ifdef CONFIG_BLOCK
  16
  17 #define kobj_to_dev(k) container_of(k, struct device, kobj)
  18 #define dev_to_disk(device) container_of(device, struct gendisk, dev)
  19 #define dev_to_part(device) container_of(device, struct hd_struct, dev)
  20
  21 extern struct device_type part_type;
  22 extern struct kobject *block_depr;
  23 extern struct class block_class;
  24
  25 extern const struct seq_operations partitions_op;
  26 extern const struct seq_operations diskstats_op;
  27
  28 enum {
  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 #include <linux/major.h>
  59 #include <linux/device.h>
  60 #include <linux/smp.h>
  61 #include <linux/string.h>
  62 #include <linux/fs.h>
  63 #include <linux/workqueue.h>
  64
  65 struct partition {
  66         unsigned char boot_ind;         /* 0x80 - active */
  67         unsigned char head;             /* starting head */
  68         unsigned char sector;           /* starting sector */
  69         unsigned char cyl;              /* starting cylinder */
  70         unsigned char sys_ind;          /* What partition type */
  71         unsigned char end_head;         /* end head */
  72         unsigned char end_sector;       /* end sector */
  73         unsigned char end_cyl;          /* end cylinder */
  74         __le32 start_sect;      /* starting sector counting from 0 */
  75         __le32 nr_sects;                /* nr of sectors in partition */
  76 } __attribute__((packed));
  77
  78 struct disk_stats {
  79         unsigned long sectors[2];       /* READs and WRITEs */
  80         unsigned long ios[2];
  81         unsigned long merges[2];
  82         unsigned long ticks[2];
  83         unsigned long io_ticks;
  84         unsigned long time_in_queue;
  85 };
  86
  87 struct hd_struct {
  88         sector_t start_sect;
  89         sector_t nr_sects;
  90         struct device dev;
  91         struct kobject *holder_dir;
  92         int policy, partno;
  93 #ifdef CONFIG_FAIL_MAKE_REQUEST
  94         int make_it_fail;
  95 #endif
  96         unsigned long stamp;
  97         int in_flight;
  98 #ifdef  CONFIG_SMP
  99         struct disk_stats *dkstats;
 100 #else
 101         struct disk_stats dkstats;
 102 #endif
 103 };
 104
 105 #define GENHD_FL_REMOVABLE                      1
 106 #define GENHD_FL_DRIVERFS                       2
 107 #define GENHD_FL_MEDIA_CHANGE_NOTIFY            4
 108 #define GENHD_FL_CD                             8
 109 #define GENHD_FL_UP                             16
 110 #define GENHD_FL_SUPPRESS_PARTITION_INFO        32
 111 #define GENHD_FL_FAIL                           64
 112
 113
 114 struct gendisk {
 115         int major;                      /* major number of driver */
 116         int first_minor;
 117         int minors;                     /* maximum number of minors, =1 for
 118                                          * disks that can't be partitioned. */
 119         char disk_name[32];             /* name of major driver */
 120         struct hd_struct **part;        /* [indexed by minor] */
 121         struct block_device_operations *fops;
 122         struct request_queue *queue;
 123         void *private_data;
 124         sector_t capacity;
 125
 126         int flags;
 127         struct device *driverfs_dev;  // FIXME: remove
 128         struct device dev;
 129         struct kobject *holder_dir;
 130         struct kobject *slave_dir;
 131
 132         struct timer_rand_state *random;
 133         int policy;
 134
 135         atomic_t sync_io;               /* RAID */
 136         unsigned long stamp;
 137         int in_flight;
 138 #ifdef  CONFIG_SMP
 139         struct disk_stats *dkstats;
 140 #else
 141         struct disk_stats dkstats;
 142 #endif
 143         struct work_struct async_notify;
 144 };
 145
 146 /*
 147  * Macros to operate on percpu disk statistics:
 148  *
 149  * The __ variants should only be called in critical sections. The full
 150  * variants disable/enable preemption.
 151  */
 152 static inline struct hd_struct *get_part(struct gendisk *gendiskp,
 153                                          sector_t sector)
 154 {
 155         struct hd_struct *part;
 156         int i;
 157         for (i = 0; i < gendiskp->minors - 1; i++) {
 158                 part = gendiskp->part[i];
 159                 if (part && part->start_sect <= sector
 160                     && sector < part->start_sect + part->nr_sects)
 161                         return part;
 162         }
 163         return NULL;
 164 }
 165
 166 #ifdef  CONFIG_SMP
 167 #define __disk_stat_add(gendiskp, field, addnd)         \
 168         (per_cpu_ptr(gendiskp->dkstats, smp_processor_id())->field += addnd)
 169
 170 #define disk_stat_read(gendiskp, field)                                 \
 171 ({                                                                      \
 172         typeof(gendiskp->dkstats->field) res = 0;                       \
 173         int i;                                                          \
 174         for_each_possible_cpu(i)                                        \
 175                 res += per_cpu_ptr(gendiskp->dkstats, i)->field;        \
 176         res;                                                            \
 177 })
 178
 179 static inline void disk_stat_set_all(struct gendisk *gendiskp, int value)       {
 180         int i;
 181         for_each_possible_cpu(i)
 182                 memset(per_cpu_ptr(gendiskp->dkstats, i), value,
 183                                 sizeof (struct disk_stats));
 184 }
 185
 186 #define __part_stat_add(part, field, addnd)                             \
 187         (per_cpu_ptr(part->dkstats, smp_processor_id())->field += addnd)
 188
 189 #define __all_stat_add(gendiskp, field, addnd, sector)          \
 190 ({                                                              \
 191         struct hd_struct *part = get_part(gendiskp, sector);    \
 192         if (part)                                               \
 193                 __part_stat_add(part, field, addnd);            \
 194         __disk_stat_add(gendiskp, field, addnd);                \
 195 })
 196
 197 #define part_stat_read(part, field)                                     \
 198 ({                                                                      \
 199         typeof(part->dkstats->field) res = 0;                           \
 200         int i;                                                          \
 201         for_each_possible_cpu(i)                                        \
 202                 res += per_cpu_ptr(part->dkstats, i)->field;            \
 203         res;                                                            \
 204 })
 205
 206 static inline void part_stat_set_all(struct hd_struct *part, int value) {
 207         int i;
 208         for_each_possible_cpu(i)
 209                 memset(per_cpu_ptr(part->dkstats, i), value,
 210                        sizeof(struct disk_stats));
 211 }
 212
 213 #else /* !CONFIG_SMP */
 214 #define __disk_stat_add(gendiskp, field, addnd) \
 215                                 (gendiskp->dkstats.field += addnd)
 216 #define disk_stat_read(gendiskp, field) (gendiskp->dkstats.field)
 217
 218 static inline void disk_stat_set_all(struct gendisk *gendiskp, int value)
 219 {
 220         memset(&gendiskp->dkstats, value, sizeof (struct disk_stats));
 221 }
 222
 223 #define __part_stat_add(part, field, addnd) \
 224         (part->dkstats.field += addnd)
 225
 226 #define __all_stat_add(gendiskp, field, addnd, sector)          \
 227 ({                                                              \
 228         struct hd_struct *part = get_part(gendiskp, sector);    \
 229         if (part)                                               \
 230                 part->dkstats.field += addnd;                   \
 231         __disk_stat_add(gendiskp, field, addnd);                \
 232 })
 233
 234 #define part_stat_read(part, field)     (part->dkstats.field)
 235
 236 static inline void part_stat_set_all(struct hd_struct *part, int value)
 237 {
 238         memset(&part->dkstats, value, sizeof(struct disk_stats));
 239 }
 240
 241 #endif /* CONFIG_SMP */
 242
 243 #define disk_stat_add(gendiskp, field, addnd)                   \
 244         do {                                                    \
 245                 preempt_disable();                              \
 246                 __disk_stat_add(gendiskp, field, addnd);        \
 247                 preempt_enable();                               \
 248         } while (0)
 249
 250 #define __disk_stat_dec(gendiskp, field) __disk_stat_add(gendiskp, field, -1)
 251 #define disk_stat_dec(gendiskp, field) disk_stat_add(gendiskp, field, -1)
 252
 253 #define __disk_stat_inc(gendiskp, field) __disk_stat_add(gendiskp, field, 1)
 254 #define disk_stat_inc(gendiskp, field) disk_stat_add(gendiskp, field, 1)
 255
 256 #define __disk_stat_sub(gendiskp, field, subnd) \
 257                 __disk_stat_add(gendiskp, field, -subnd)
 258 #define disk_stat_sub(gendiskp, field, subnd) \
 259                 disk_stat_add(gendiskp, field, -subnd)
 260
 261 #define part_stat_add(gendiskp, field, addnd)           \
 262         do {                                            \
 263                 preempt_disable();                      \
 264                 __part_stat_add(gendiskp, field, addnd);\
 265                 preempt_enable();                       \
 266         } while (0)
 267
 268 #define __part_stat_dec(gendiskp, field) __part_stat_add(gendiskp, field, -1)
 269 #define part_stat_dec(gendiskp, field) part_stat_add(gendiskp, field, -1)
 270
 271 #define __part_stat_inc(gendiskp, field) __part_stat_add(gendiskp, field, 1)
 272 #define part_stat_inc(gendiskp, field) part_stat_add(gendiskp, field, 1)
 273
 274 #define __part_stat_sub(gendiskp, field, subnd) \
 275                 __part_stat_add(gendiskp, field, -subnd)
 276 #define part_stat_sub(gendiskp, field, subnd) \
 277                 part_stat_add(gendiskp, field, -subnd)
 278
 279 #define all_stat_add(gendiskp, field, addnd, sector)            \
 280         do {                                                    \
 281                 preempt_disable();                              \
 282                 __all_stat_add(gendiskp, field, addnd, sector); \
 283                 preempt_enable();                               \
 284         } while (0)
 285
 286 #define __all_stat_dec(gendiskp, field, sector) \
 287                 __all_stat_add(gendiskp, field, -1, sector)
 288 #define all_stat_dec(gendiskp, field, sector) \
 289                 all_stat_add(gendiskp, field, -1, sector)
 290
 291 #define __all_stat_inc(gendiskp, field, sector) \
 292                 __all_stat_add(gendiskp, field, 1, sector)
 293 #define all_stat_inc(gendiskp, field, sector) \
 294                 all_stat_add(gendiskp, field, 1, sector)
 295
 296 #define __all_stat_sub(gendiskp, field, subnd, sector) \
 297                 __all_stat_add(gendiskp, field, -subnd, sector)
 298 #define all_stat_sub(gendiskp, field, subnd, sector) \
 299                 all_stat_add(gendiskp, field, -subnd, sector)
 300
 301 /* Inlines to alloc and free disk stats in struct gendisk */
 302 #ifdef  CONFIG_SMP
 303 static inline int init_disk_stats(struct gendisk *disk)
 304 {
 305         disk->dkstats = alloc_percpu(struct disk_stats);
 306         if (!disk->dkstats)
 307                 return 0;
 308         return 1;
 309 }
 310
 311 static inline void free_disk_stats(struct gendisk *disk)
 312 {
 313         free_percpu(disk->dkstats);
 314 }
 315
 316 static inline int init_part_stats(struct hd_struct *part)
 317 {
 318         part->dkstats = alloc_percpu(struct disk_stats);
 319         if (!part->dkstats)
 320                 return 0;
 321         return 1;
 322 }
 323
 324 static inline void free_part_stats(struct hd_struct *part)
 325 {
 326         free_percpu(part->dkstats);
 327 }
 328
 329 #else   /* CONFIG_SMP */
 330 static inline int init_disk_stats(struct gendisk *disk)
 331 {
 332         return 1;
 333 }
 334
 335 static inline void free_disk_stats(struct gendisk *disk)
 336 {
 337 }
 338
 339 static inline int init_part_stats(struct hd_struct *part)
 340 {
 341         return 1;
 342 }
 343
 344 static inline void free_part_stats(struct hd_struct *part)
 345 {
 346 }
 347 #endif  /* CONFIG_SMP */
 348
 349 /* drivers/block/ll_rw_blk.c */
 350 extern void disk_round_stats(struct gendisk *disk);
 351 extern void part_round_stats(struct hd_struct *part);
 352
 353 /* drivers/block/genhd.c */
 354 extern int get_blkdev_list(char *, int);
 355 extern void add_disk(struct gendisk *disk);
 356 extern void del_gendisk(struct gendisk *gp);
 357 extern void unlink_gendisk(struct gendisk *gp);
 358 extern struct gendisk *get_gendisk(dev_t dev, int *part);
 359
 360 extern void set_device_ro(struct block_device *bdev, int flag);
 361 extern void set_disk_ro(struct gendisk *disk, int flag);
 362
 363 /* drivers/char/random.c */
 364 extern void add_disk_randomness(struct gendisk *disk);
 365 extern void rand_initialize_disk(struct gendisk *disk);
 366
 367 static inline sector_t get_start_sect(struct block_device *bdev)
 368 {
 369         return bdev->bd_contains == bdev ? 0 : bdev->bd_part->start_sect;
 370 }
 371 static inline sector_t get_capacity(struct gendisk *disk)
 372 {
 373         return disk->capacity;
 374 }
 375 static inline void set_capacity(struct gendisk *disk, sector_t size)
 376 {
 377         disk->capacity = size;
 378 }
 379
 380 #ifdef CONFIG_SOLARIS_X86_PARTITION
 381
 382 #define SOLARIS_X86_NUMSLICE    16
 383 #define SOLARIS_X86_VTOC_SANE   (0x600DDEEEUL)
 384
 385 struct solaris_x86_slice {
 386         __le16 s_tag;           /* ID tag of partition */
 387         __le16 s_flag;          /* permission flags */
 388         __le32 s_start;         /* start sector no of partition */
 389         __le32 s_size;          /* # of blocks in partition */
 390 };
 391
 392 struct solaris_x86_vtoc {
 393         unsigned int v_bootinfo[3];     /* info needed by mboot (unsupported) */
 394         __le32 v_sanity;                /* to verify vtoc sanity */
 395         __le32 v_version;               /* layout version */
 396         char    v_volume[8];            /* volume name */
 397         __le16  v_sectorsz;             /* sector size in bytes */
 398         __le16  v_nparts;               /* number of partitions */
 399         unsigned int v_reserved[10];    /* free space */
 400         struct solaris_x86_slice
 401                 v_slice[SOLARIS_X86_NUMSLICE]; /* slice headers */
 402         unsigned int timestamp[SOLARIS_X86_NUMSLICE]; /* timestamp (unsupported) */
 403         char    v_asciilabel[128];      /* for compatibility */
 404 };
 405
 406 #endif /* CONFIG_SOLARIS_X86_PARTITION */
 407
 408 #ifdef CONFIG_BSD_DISKLABEL
 409 /*
 410  * BSD disklabel support by Yossi Gottlieb <yogo@math.tau.ac.il>
 411  * updated by Marc Espie <Marc.Espie@openbsd.org>
 412  */
 413
 414 /* check against BSD src/sys/sys/disklabel.h for consistency */
 415
 416 #define BSD_DISKMAGIC   (0x82564557UL)  /* The disk magic number */
 417 #define BSD_MAXPARTITIONS       16
 418 #define OPENBSD_MAXPARTITIONS   16
 419 #define BSD_FS_UNUSED           0       /* disklabel unused partition entry ID */
 420 struct bsd_disklabel {
 421         __le32  d_magic;                /* the magic number */
 422         __s16   d_type;                 /* drive type */
 423         __s16   d_subtype;              /* controller/d_type specific */
 424         char    d_typename[16];         /* type name, e.g. "eagle" */
 425         char    d_packname[16];                 /* pack identifier */
 426         __u32   d_secsize;              /* # of bytes per sector */
 427         __u32   d_nsectors;             /* # of data sectors per track */
 428         __u32   d_ntracks;              /* # of tracks per cylinder */
 429         __u32   d_ncylinders;           /* # of data cylinders per unit */
 430         __u32   d_secpercyl;            /* # of data sectors per cylinder */
 431         __u32   d_secperunit;           /* # of data sectors per unit */
 432         __u16   d_sparespertrack;       /* # of spare sectors per track */
 433         __u16   d_sparespercyl;         /* # of spare sectors per cylinder */
 434         __u32   d_acylinders;           /* # of alt. cylinders per unit */
 435         __u16   d_rpm;                  /* rotational speed */
 436         __u16   d_interleave;           /* hardware sector interleave */
 437         __u16   d_trackskew;            /* sector 0 skew, per track */
 438         __u16   d_cylskew;              /* sector 0 skew, per cylinder */
 439         __u32   d_headswitch;           /* head switch time, usec */
 440         __u32   d_trkseek;              /* track-to-track seek, usec */
 441         __u32   d_flags;                /* generic flags */
 442 #define NDDATA 5
 443         __u32   d_drivedata[NDDATA];    /* drive-type specific information */
 444 #define NSPARE 5
 445         __u32   d_spare[NSPARE];        /* reserved for future use */
 446         __le32  d_magic2;               /* the magic number (again) */
 447         __le16  d_checksum;             /* xor of data incl. partitions */
 448
 449                         /* filesystem and partition information: */
 450         __le16  d_npartitions;          /* number of partitions in following */
 451         __le32  d_bbsize;               /* size of boot area at sn0, bytes */
 452         __le32  d_sbsize;               /* max size of fs superblock, bytes */
 453         struct  bsd_partition {         /* the partition table */
 454                 __le32  p_size;         /* number of sectors in partition */
 455                 __le32  p_offset;       /* starting sector */
 456                 __le32  p_fsize;        /* filesystem basic fragment size */
 457                 __u8    p_fstype;       /* filesystem type, see below */
 458                 __u8    p_frag;         /* filesystem fragments per block */
 459                 __le16  p_cpg;          /* filesystem cylinders per group */
 460         } d_partitions[BSD_MAXPARTITIONS];      /* actually may be more */
 461 };
 462
 463 #endif  /* CONFIG_BSD_DISKLABEL */
 464
 465 #ifdef CONFIG_UNIXWARE_DISKLABEL
 466 /*
 467  * Unixware slices support by Andrzej Krzysztofowicz <ankry@mif.pg.gda.pl>
 468  * and Krzysztof G. Baranowski <kgb@knm.org.pl>
 469  */
 470
 471 #define UNIXWARE_DISKMAGIC     (0xCA5E600DUL)   /* The disk magic number */
 472 #define UNIXWARE_DISKMAGIC2    (0x600DDEEEUL)   /* The slice table magic nr */
 473 #define UNIXWARE_NUMSLICE      16
 474 #define UNIXWARE_FS_UNUSED     0                /* Unused slice entry ID */
 475
 476 struct unixware_slice {
 477         __le16   s_label;       /* label */
 478         __le16   s_flags;       /* permission flags */
 479         __le32   start_sect;    /* starting sector */
 480         __le32   nr_sects;      /* number of sectors in slice */
 481 };
 482
 483 struct unixware_disklabel {
 484         __le32   d_type;                /* drive type */
 485         __le32   d_magic;                /* the magic number */
 486         __le32   d_version;              /* version number */
 487         char    d_serial[12];           /* serial number of the device */
 488         __le32   d_ncylinders;           /* # of data cylinders per device */
 489         __le32   d_ntracks;              /* # of tracks per cylinder */
 490         __le32   d_nsectors;             /* # of data sectors per track */
 491         __le32   d_secsize;              /* # of bytes per sector */
 492         __le32   d_part_start;           /* # of first sector of this partition */
 493         __le32   d_unknown1[12];         /* ? */
 494         __le32  d_alt_tbl;              /* byte offset of alternate table */
 495         __le32  d_alt_len;              /* byte length of alternate table */
 496         __le32  d_phys_cyl;             /* # of physical cylinders per device */
 497         __le32  d_phys_trk;             /* # of physical tracks per cylinder */
 498         __le32  d_phys_sec;             /* # of physical sectors per track */
 499         __le32  d_phys_bytes;           /* # of physical bytes per sector */
 500         __le32  d_unknown2;             /* ? */
 501         __le32   d_unknown3;             /* ? */
 502         __le32  d_pad[8];               /* pad */
 503
 504         struct unixware_vtoc {
 505                 __le32  v_magic;                /* the magic number */
 506                 __le32  v_version;              /* version number */
 507                 char    v_name[8];              /* volume name */
 508                 __le16  v_nslices;              /* # of slices */
 509                 __le16  v_unknown1;             /* ? */
 510                 __le32  v_reserved[10];         /* reserved */
 511                 struct unixware_slice
 512                         v_slice[UNIXWARE_NUMSLICE];     /* slice headers */
 513         } vtoc;
 514
 515 };  /* 408 */
 516
 517 #endif /* CONFIG_UNIXWARE_DISKLABEL */
 518
 519 #ifdef CONFIG_MINIX_SUBPARTITION
 520 #   define MINIX_NR_SUBPARTITIONS  4
 521 #endif /* CONFIG_MINIX_SUBPARTITION */
 522
 523 #define ADDPART_FLAG_NONE       0
 524 #define ADDPART_FLAG_RAID       1
 525 #define ADDPART_FLAG_WHOLEDISK  2
 526
 527 extern dev_t blk_lookup_devt(const char *name);
 528 extern char *disk_name (struct gendisk *hd, int part, char *buf);
 529
 530 extern int rescan_partitions(struct gendisk *disk, struct block_device *bdev);
 531 extern void add_partition(struct gendisk *, int, sector_t, sector_t, int);
 532 extern void delete_partition(struct gendisk *, int);
 533 extern void printk_all_partitions(void);
 534
 535 extern struct gendisk *alloc_disk_node(int minors, int node_id);
 536 extern struct gendisk *alloc_disk(int minors);
 537 extern struct kobject *get_disk(struct gendisk *disk);
 538 extern void put_disk(struct gendisk *disk);
 539 extern void blk_register_region(dev_t devt, unsigned long range,
 540                         struct module *module,
 541                         struct kobject *(*probe)(dev_t, int *, void *),
 542                         int (*lock)(dev_t, void *),
 543                         void *data);
 544 extern void blk_unregister_region(dev_t devt, unsigned long range);
 545
 546 static inline struct block_device *bdget_disk(struct gendisk *disk, int index)
 547 {
 548         return bdget(MKDEV(disk->major, disk->first_minor) + index);
 549 }
 550
 551 #else /* CONFIG_BLOCK */
 552
 553 static inline void printk_all_partitions(void) { }
 554
 555 static inline dev_t blk_lookup_devt(const char *name)
 556 {
 557         dev_t devt = MKDEV(0, 0);
 558         return devt;
 559 }
 560
 561 #endif /* CONFIG_BLOCK */
 562
 563 #endif /* _LINUX_GENHD_H */