iokit/IOKit/storage/IONeXTPartitionScheme.h

   1 /*
   2  * Copyright (c) 1998-2000 Apple Computer, Inc. All rights reserved.
   3  *
   4  * @APPLE_LICENSE_HEADER_START@
   5  *
   6  * The contents of this file constitute Original Code as defined in and
   7  * are subject to the Apple Public Source License Version 1.1 (the
   8  * "License").  You may not use this file except in compliance with the
   9  * License.  Please obtain a copy of the License at
  10  * http://www.apple.com/publicsource and read it before using this file.
  11  *
  12  * This Original Code and all software distributed under the License are
  13  * distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY KIND, EITHER
  14  * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
  15  * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
  16  * FITNESS FOR A PARTICULAR PURPOSE OR NON-INFRINGEMENT.  Please see the
  17  * License for the specific language governing rights and limitations
  18  * under the License.
  19  *
  20  * @APPLE_LICENSE_HEADER_END@
  21  */
  22
  23 #ifndef _IONEXTPARTITIONSCHEME_H
  24 #define _IONEXTPARTITIONSCHEME_H
  25
  26 #include <IOKit/IOTypes.h>
  27
  28 /*
  29  * NeXT Partition Map Definitions
  30  */
  31
  32 #pragma pack(2) /* (enable 16-bit struct packing for dl_un, disk[tab,_label]) */
  33
  34 #include <sys/disktab.h>
  35
  36 /* Structure constants. */
  37
  38 #define MAXLBLLEN 24                    /* (length of disk name)              */
  39 #define NBAD      1670                  /* (size of bad sector table in map)  */
  40 #define NLABELS   4                     /* (number of partition maps on disk) */
  41
  42 /* Structure aliases, for disktab and dl_un fields. */
  43
  44 #define dl_name          dl_dt.d_name
  45 #define dl_type          dl_dt.d_type
  46 #define dl_part          dl_dt.d_partitions
  47 #define dl_front         dl_dt.d_front
  48 #define dl_back          dl_dt.d_back
  49 #define dl_ngroups       dl_dt.d_ngroups
  50 #define dl_ag_size       dl_dt.d_ag_size
  51 #define dl_ag_alts       dl_dt.d_ag_alts
  52 #define dl_ag_off        dl_dt.d_ag_off
  53 #define dl_secsize       dl_dt.d_secsize
  54 #define dl_ncyl          dl_dt.d_ncylinders
  55 #define dl_nsect         dl_dt.d_nsectors
  56 #define dl_ntrack        dl_dt.d_ntracks
  57 #define dl_rpm           dl_dt.d_rpm
  58 #define dl_bootfile      dl_dt.d_bootfile
  59 #define dl_boot0_blkno   dl_dt.d_boot0_blkno
  60 #define dl_hostname      dl_dt.d_hostname
  61 #define dl_rootpartition dl_dt.d_rootpartition
  62 #define dl_rwpartition   dl_dt.d_rwpartition
  63 #define dl_v3_checksum   dl_un.DL_v3_checksum
  64 #define dl_bad           dl_un.DL_bad
  65
  66 /* Partition map, as found in block zero (or a redundant block) of the disk. */
  67
  68 typedef union
  69 {
  70     UInt16         DL_v3_checksum;       /* (V3: ones complement checksum)    */
  71     SInt32         DL_bad[NBAD];         /* (V1-V2: bad sector table)         */
  72 } dl_un_t;
  73
  74 typedef struct disk_label
  75 {
  76     SInt32         dl_version;           /* (unique signature for map)        */
  77     SInt32         dl_label_blkno;       /* (block on which this map resides) */
  78     SInt32         dl_size;              /* (device block count)              */
  79     char           dl_label[MAXLBLLEN];  /* (device name)                     */
  80     UInt32         dl_flags;             /* (device flags)                    */
  81     UInt32         dl_tag;               /* (device tag)                      */
  82     struct disktab dl_dt;                /* (device info, partition entries)  */
  83     dl_un_t        dl_un;
  84     UInt16         dl_checksum;          /* (V1-V2: ones complement checksum) */
  85
  86                    /* (add things here so dl_checksum stays in a fixed place) */
  87 } disk_label_t;
  88
  89 /* Partition map signature (dl_version). */
  90
  91 #define DL_V1           0x4e655854                     /* (version 1: "NeXT") */
  92 #define DL_V2           0x646c5632                     /* (version 2: "dlV2") */
  93 #define DL_V3           0x646c5633                     /* (version 3: "dlV3") */
  94 #define DL_VERSION      DL_V3                          /* (default version)   */
  95
  96 /* Partition map flags (dl_flags). */
  97
  98 #define DL_UNINIT       0x80000000                     /* (is uninitialized?) */
  99
 100 #pragma options align=reset              /* (reset to default struct packing) */
 101
 102 /*
 103  * Kernel
 104  */
 105
 106 #if defined(KERNEL) && defined(__cplusplus)
 107
 108 #include <IOKit/storage/IOPartitionScheme.h>
 109
 110 /*
 111  * Class
 112  */
 113
 114 class IONeXTPartitionScheme : public IOPartitionScheme
 115 {
 116     OSDeclareDefaultStructors(IONeXTPartitionScheme);
 117
 118 private:
 119
 120     /*
 121      * Compute a 16-bit (big-endian) checksum over the specified data range.
 122      */
 123
 124     UInt16 checksum16(void * data, UInt32 bytes) const;
 125
 126 protected:
 127
 128     struct ExpansionData { /* */ };
 129     ExpansionData * _expansionData;
 130
 131     OSSet * _partitions;    /* (set of media objects representing partitions) */
 132
 133     /*
 134      * Free all of this object's outstanding resources.
 135      */
 136
 137     virtual void free(void);
 138
 139     /*
 140      * Scan the provider media for a NeXT partition map.    Returns the set
 141      * of media objects representing each of the partitions (the retain for
 142      * the set is passed to the caller), or null should no partition map be
 143      * found.  The default probe score can be adjusted up or down, based on
 144      * the confidence of the scan.
 145      */
 146
 147     virtual OSSet * scan(SInt32 * score);
 148
 149     /*
 150      * Ask whether the given partition is used.
 151      */
 152
 153     virtual bool isPartitionUsed(partition_t * partition);
 154
 155     /*
 156      * Ask whether the given partition appears to be corrupt. A partition that
 157      * is corrupt will cause the failure of the NeXT partition map recognition
 158      * altogether.
 159      */
 160
 161     virtual bool isPartitionCorrupt( partition_t *  partition,
 162                                      UInt32         partitionID,
 163                                      UInt64         nextBase,
 164                                      disk_label_t * nextMap );
 165
 166     /*
 167      * Ask whether the given partition appears to be invalid.  A partition that
 168      * is invalid will cause it to be skipped in the scan, but will not cause a
 169      * failure of the NeXT partition map recognition.
 170      */
 171
 172     virtual bool isPartitionInvalid( partition_t *  partition,
 173                                      UInt32         partitionID,
 174                                      UInt64         nextBase,
 175                                      disk_label_t * nextMap );
 176
 177     /*
 178      * Instantiate a new media object to represent the given partition.
 179      */
 180
 181     virtual IOMedia * instantiateMediaObject( partition_t *  partition,
 182                                               UInt32         partitionID,
 183                                               UInt64         nextBase,
 184                                               disk_label_t * nextMap );
 185
 186     /*
 187      * Allocate a new media object (called from instantiateMediaObject).
 188      */
 189
 190     virtual IOMedia * instantiateDesiredMediaObject( partition_t *  partition,
 191                                                      UInt32         partitionID,
 192                                                      UInt64         nextBase,
 193                                                      disk_label_t * nextMap );
 194
 195 public:
 196
 197     /*
 198      * Initialize this object's minimal state.
 199      */
 200
 201     virtual bool init(OSDictionary * properties = 0);
 202
 203     /*
 204      * Determine whether the provider media contains a NeXT partition map.
 205      */
 206
 207     virtual IOService * probe(IOService * provider, SInt32 * score);
 208
 209     /*
 210      * Publish the new media objects which represent our partitions.
 211      */
 212
 213     virtual bool start(IOService * provider);
 214
 215     OSMetaClassDeclareReservedUnused(IONeXTPartitionScheme,  0);
 216     OSMetaClassDeclareReservedUnused(IONeXTPartitionScheme,  1);
 217     OSMetaClassDeclareReservedUnused(IONeXTPartitionScheme,  2);
 218     OSMetaClassDeclareReservedUnused(IONeXTPartitionScheme,  3);
 219     OSMetaClassDeclareReservedUnused(IONeXTPartitionScheme,  4);
 220     OSMetaClassDeclareReservedUnused(IONeXTPartitionScheme,  5);
 221     OSMetaClassDeclareReservedUnused(IONeXTPartitionScheme,  6);
 222     OSMetaClassDeclareReservedUnused(IONeXTPartitionScheme,  7);
 223     OSMetaClassDeclareReservedUnused(IONeXTPartitionScheme,  8);
 224     OSMetaClassDeclareReservedUnused(IONeXTPartitionScheme,  9);
 225     OSMetaClassDeclareReservedUnused(IONeXTPartitionScheme, 10);
 226     OSMetaClassDeclareReservedUnused(IONeXTPartitionScheme, 11);
 227     OSMetaClassDeclareReservedUnused(IONeXTPartitionScheme, 12);
 228     OSMetaClassDeclareReservedUnused(IONeXTPartitionScheme, 13);
 229     OSMetaClassDeclareReservedUnused(IONeXTPartitionScheme, 14);
 230     OSMetaClassDeclareReservedUnused(IONeXTPartitionScheme, 15);
 231 };
 232
 233 #endif /* defined(KERNEL) && defined(__cplusplus) */
 234
 235 #endif /* !_IONEXTPARTITIONSCHEME_H */