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 
  14 #define CONFIG_MSDOS_PARTITION 1
  15 
  16 #ifdef __alpha__
  17 #define CONFIG_OSF_PARTITION 1
  18 #endif
  19 
  20 #if defined(__sparc__) || defined(CONFIG_SMD_DISKLABEL)
  21 #define CONFIG_SUN_PARTITION 1
  22 #endif
  23 
  24 /* These two have identical behaviour; use the second one if DOS fdisk gets
  25    confused about extended/logical partitions starting past cylinder 1023. */
  26 #define DOS_EXTENDED_PARTITION 5
  27 #define LINUX_EXTENDED_PARTITION 0x85
  28 
  29 #define DM6_PARTITION           0x54    /* has DDO: use xlated geom & offset */
  30 #define EZD_PARTITION           0x55    /* EZ-DRIVE:  same as DM6 (we think) */
  31 #define DM6_AUX1PARTITION       0x51    /* no DDO:  use xlated geom */
  32 #define DM6_AUX3PARTITION       0x53    /* no DDO:  use xlated geom */
  33         
  34 struct partition {
  35         unsigned char boot_ind;         /* 0x80 - active */
  36         unsigned char head;             /* starting head */
  37         unsigned char sector;           /* starting sector */
  38         unsigned char cyl;              /* starting cylinder */
  39         unsigned char sys_ind;          /* What partition type */
  40         unsigned char end_head;         /* end head */
  41         unsigned char end_sector;       /* end sector */
  42         unsigned char end_cyl;          /* end cylinder */
  43         unsigned int start_sect;        /* starting sector counting from 0 */
  44         unsigned int nr_sects;          /* nr of sectors in partition */
  45 };
  46 
  47 struct hd_struct {
  48         long start_sect;
  49         long nr_sects;
  50 };
  51 
  52 struct gendisk {
  53         int major;                      /* major number of driver */
  54         const char *major_name;         /* name of major driver */
  55         int minor_shift;                /* number of times minor is shifted to
  56                                            get real minor */
  57         int max_p;                      /* maximum partitions per device */
  58         int max_nr;                     /* maximum number of real devices */
  59 
  60         void (*init)(struct gendisk *); /* Initialization called before we do our thing */
  61         struct hd_struct *part;         /* partition table */
  62         int *sizes;                     /* device size in blocks, copied to blk_size[] */
  63         int nr_real;                    /* number of real devices */
  64 
  65         void *real_devices;             /* internal use */
  66         struct gendisk *next;
  67 };
  68 
  69 #ifdef CONFIG_BSD_DISKLABEL
  70 /*
  71  * BSD disklabel support by Yossi Gottlieb <yogo@math.tau.ac.il>
  72  */
  73 
  74 #define BSD_PARTITION           0xa5    /* Partition ID */
  75 
  76 #define BSD_DISKMAGIC   (0x82564557UL)  /* The disk magic number */
  77 #define BSD_MAXPARTITIONS       8
  78 #define BSD_FS_UNUSED           0       /* disklabel unused partition entry ID */
  79 struct bsd_disklabel {
  80         __u32   d_magic;                /* the magic number */
  81         __s16   d_type;                 /* drive type */
  82         __s16   d_subtype;              /* controller/d_type specific */
  83         char    d_typename[16];         /* type name, e.g. "eagle" */
  84         char    d_packname[16];                 /* pack identifier */ 
  85         __u32   d_secsize;              /* # of bytes per sector */
  86         __u32   d_nsectors;             /* # of data sectors per track */
  87         __u32   d_ntracks;              /* # of tracks per cylinder */
  88         __u32   d_ncylinders;           /* # of data cylinders per unit */
  89         __u32   d_secpercyl;            /* # of data sectors per cylinder */
  90         __u32   d_secperunit;           /* # of data sectors per unit */
  91         __u16   d_sparespertrack;       /* # of spare sectors per track */
  92         __u16   d_sparespercyl;         /* # of spare sectors per cylinder */
  93         __u32   d_acylinders;           /* # of alt. cylinders per unit */
  94         __u16   d_rpm;                  /* rotational speed */
  95         __u16   d_interleave;           /* hardware sector interleave */
  96         __u16   d_trackskew;            /* sector 0 skew, per track */
  97         __u16   d_cylskew;              /* sector 0 skew, per cylinder */
  98         __u32   d_headswitch;           /* head switch time, usec */
  99         __u32   d_trkseek;              /* track-to-track seek, usec */
 100         __u32   d_flags;                /* generic flags */
 101 #define NDDATA 5
 102         __u32   d_drivedata[NDDATA];    /* drive-type specific information */
 103 #define NSPARE 5
 104         __u32   d_spare[NSPARE];        /* reserved for future use */
 105         __u32   d_magic2;               /* the magic number (again) */
 106         __u16   d_checksum;             /* xor of data incl. partitions */
 107 
 108                         /* filesystem and partition information: */
 109         __u16   d_npartitions;          /* number of partitions in following */
 110         __u32   d_bbsize;               /* size of boot area at sn0, bytes */
 111         __u32   d_sbsize;               /* max size of fs superblock, bytes */
 112         struct  bsd_partition {         /* the partition table */
 113                 __u32   p_size;         /* number of sectors in partition */
 114                 __u32   p_offset;       /* starting sector */
 115                 __u32   p_fsize;        /* filesystem basic fragment size */
 116                 __u8    p_fstype;       /* filesystem type, see below */
 117                 __u8    p_frag;         /* filesystem fragments per block */
 118                 __u16   p_cpg;          /* filesystem cylinders per group */
 119         } d_partitions[BSD_MAXPARTITIONS];      /* actually may be more */
 120 };
 121 
 122 #endif  /* CONFIG_BSD_DISKLABEL */
 123 
 124 extern struct gendisk *gendisk_head;    /* linked list of disks */
 125 
 126 /*
 127  * disk_name() is used by genhd.c and md.c.
 128  * It formats the devicename of the indicated disk
 129  * into the supplied buffer, and returns a pointer
 130  * to that same buffer (for convenience).
 131  */
 132 char *disk_name (struct gendisk *hd, int minor, char *buf);
 133 
 134 #endif
/* */
root/include/linux/genhd.h

INCLUDED FROM
