rom/filesys/fat/fat_fs.h

   1 /*
   2  * fat.handler - FAT12/16/32 filesystem handler
   3  *
   4  * Copyright © 2006 Marek Szyprowski
   5  * Copyright © 2007-2012 The AROS Development Team
   6  *
   7  * This program is free software; you can redistribute it and/or modify it
   8  * under the same terms as AROS itself.
   9  *
  10  * $Id$
  11  */
  12
  13 #ifndef FAT_HANDLER_H
  14 #define FAT_HANDLER_H
  15
  16 #define DEBUG_DIRENTRY      0
  17 #define DEBUG_FILE          0
  18 #define DEBUG_DUMP          0
  19 #define DEBUG_LOCK          0
  20 #define DEBUG_NAMES         0
  21 #define DEBUG_NOTIFY        0
  22 #define DEBUG_OPS           0
  23 #define DEBUG_PACKETS       0
  24 #define DEBUG_CACHESTATS    0
  25 #define DEBUG_MISC          0
  26
  27 #include <aros/libcall.h>
  28 #include <devices/trackdisk.h>
  29
  30 #include "fat_struct.h"
  31
  32 #include "cache.h"
  33
  34 /* filesystem structures */
  35
  36 #define ID_FAT_DISK 0x46415400UL
  37
  38 #define ID_FAT12_DISK 0x46415400UL
  39 #define ID_FAT16_DISK 0x46415401UL
  40 #define ID_FAT32_DISK 0x46415402UL
  41
  42 #define ACTION_VOLUME_ADD 16000
  43 #define ACTION_VOLUME_REMOVE 16001
  44
  45 extern struct Globals *glob;
  46
  47 #define DEF_POOL_SIZE 65536
  48 #define DEF_POOL_THRESHOLD DEF_POOL_SIZE
  49 #define DEF_BUFF_LINES 128
  50 #define DEF_READ_AHEAD 16*1024
  51
  52
  53 /* a handle on something, file or directory */
  54 struct IOHandle {
  55     struct FSSuper      *sb;            /* filesystem data */
  56
  57     ULONG               first_cluster;  /* first cluster of this file */
  58     ULONG               cur_cluster;    /* cluster that the current sector is within */
  59
  60     ULONG               cluster_offset; /* cluster number of this cluster within the current file */
  61
  62     ULONG               first_sector;   /* first sector in the first cluster, for fat12/16 root dir */
  63     ULONG               cur_sector;     /* sector number our block is currently in */
  64
  65     ULONG               sector_offset;  /* current sector as an offset in the current cluster
  66                                            i.e. cur = sector(cur_cluster) + offset */
  67
  68     APTR block;         /* current block from the cache */
  69     UBYTE *data;         /* current data buffer (from cache) */
  70 };
  71
  72 /* a handle on a directory */
  73 struct DirHandle {
  74     struct IOHandle     ioh;
  75
  76     ULONG               cur_index;      /* last entry returned, for GetNextDirEntry */
  77 };
  78
  79 /* single directory entry */
  80 struct DirEntry {
  81     struct FSSuper      *sb;            /* filesystem data */
  82
  83     ULONG               cluster;        /* cluster the containing directory starts at */
  84     ULONG               index;          /* index of this entry */
  85
  86     ULONG               pos;            /* byte offset within directory that the entry came from */
  87
  88     union {
  89         struct FATDirEntry      entry;
  90         struct FATLongDirEntry  long_entry;
  91     } e;
  92 };
  93
  94 #define FAT_ROOTDIR_MARK    0xFFFFFFFFlu
  95
  96 struct GlobalLock;
  97
  98 struct ExtFileLock {
  99     /* struct FileLock */
 100     BPTR                fl_Link;
 101     IPTR                fl_Key;
 102     LONG                fl_Access;
 103     struct MsgPort *    fl_Task;
 104     BPTR                fl_Volume;
 105
 106     ULONG               magic;          /* we set this to ID_FAT_DISK so we can tell
 107                                            our locks from those of other filesystems */
 108
 109     struct MinNode      node;           /* node in the list of locks attached to the global lock */
 110     struct GlobalLock   *gl;            /* pointer to the global lock for this file */
 111
 112     struct IOHandle     ioh;            /* handle for reads and writes */
 113     ULONG               pos;            /* current seek position within the file */
 114
 115     BOOL                do_notify;      /* if set, send notification on file close (ACTION_END) */
 116     struct FSSuper      *sb;            /* pointer to sb, for unlocking when volume is removed */
 117 };
 118
 119 struct GlobalLock {
 120     struct MinNode      node;
 121
 122     ULONG               dir_cluster;    /* first cluster of the directory we're in */
 123     ULONG               dir_entry;      /* this is our dir entry within dir_cluster */
 124
 125     LONG                access;         /* access mode, shared or exclusive */
 126
 127     ULONG               first_cluster;  /* first data cluster */
 128
 129     ULONG               attr;           /* file attributes, from the dir entry */
 130     ULONG               size;           /* file size, from the dir entry */
 131
 132     UBYTE name[FAT_MAX_LONG_FILENAME];  /* copy of the name (bstr) */
 133
 134     struct MinList      locks;          /* list of ExtFileLocks opened on this file */
 135 };
 136
 137 /* a node in the list of notification requests */
 138 struct NotifyNode {
 139     struct MinNode          node;
 140
 141     struct GlobalLock       *gl;        /* pointer to global lock if this file is
 142                                            locked. if it's not, this is NULL */
 143
 144     struct NotifyRequest    *nr;        /* the request that DOS passed us */
 145 };
 146
 147 struct VolumeInfo {
 148     APTR mem_pool;
 149     ULONG id;
 150     struct MinList locks;           /* global locks */
 151     struct GlobalLock root_lock;
 152     struct MinList notifies;
 153 };
 154
 155 struct VolumeIdentity {
 156     UBYTE               name[32];     /* BCPL string */
 157     struct DateStamp    create_time;
 158 };
 159
 160 struct FSSuper {
 161     struct Node node;
 162     struct DosList *doslist;
 163
 164     struct VolumeInfo *info;
 165
 166     struct cache *cache;
 167     ULONG        first_device_sector;
 168
 169     ULONG sectorsize;
 170     ULONG sectorsize_bits;
 171
 172     ULONG cluster_sectors;
 173     ULONG clustersize;
 174     ULONG clustersize_bits;
 175     ULONG cluster_sectors_bits;
 176
 177     ULONG first_fat_sector;
 178     ULONG first_data_sector;
 179     ULONG first_rootdir_sector;
 180
 181     ULONG rootdir_sectors;
 182     ULONG total_sectors;
 183     ULONG data_sectors;
 184     ULONG clusters_count;
 185     ULONG fat_size;
 186     UWORD fat_count;
 187
 188     ULONG free_clusters;
 189     ULONG next_cluster;
 190
 191     ULONG volume_id;
 192     ULONG type;
 193     ULONG eoc_mark;
 194
 195     APTR  *fat_blocks;
 196     UBYTE **fat_buffers;
 197     ULONG fat_blocks_count;
 198
 199     ULONG fat_cachesize;
 200     ULONG fat_cachesize_bits;
 201     ULONG fat_cache_block;
 202     UWORD fat_cache_no;    /* FAT number that cached FAT blocks belong to */
 203
 204     APTR fsinfo_block;
 205     struct FATFSInfo *fsinfo_buffer;
 206
 207     ULONG rootdir_cluster;
 208     ULONG rootdir_sector;
 209
 210     struct VolumeIdentity volume;
 211
 212     /* function table */
 213     ULONG (*func_get_fat_entry)(struct FSSuper *sb, ULONG n);
 214     void  (*func_set_fat_entry)(struct FSSuper *sb, ULONG n, ULONG val);
 215     /* ... */
 216 };
 217
 218 struct Globals {
 219     /* mem/task */
 220     struct Task *ourtask;
 221     struct MsgPort *ourport;
 222     APTR mempool;
 223
 224     struct MsgPort *notifyport;
 225
 226     /* fs */
 227     struct DosList *devnode;
 228     struct FileSysStartupMsg *fssm;
 229     LONG quit;
 230     struct DosPacket *death_packet;
 231     BOOL autodetect;
 232
 233     /* io */
 234     struct IOExtTD *diskioreq;
 235     struct IOExtTD *diskchgreq;
 236     struct MsgPort *diskport;
 237     ULONG diskchgsig_bit;
 238     struct timerequest *timereq;
 239     struct MsgPort *timerport;
 240     ULONG last_num;    /* last block number that was outside boundaries */
 241     UWORD readcmd;
 242     UWORD writecmd;
 243     char timer_active;
 244     char restart_timer;
 245
 246     /* volumes */
 247     struct FSSuper *sb;    /* current sb */
 248     struct MinList sblist;   /* sbs with outstanding locks or notifies */
 249
 250     /* disk status */
 251     LONG disk_inserted;
 252     LONG disk_inhibited;
 253
 254     /* Character sets translation */
 255     UBYTE from_unicode[65536];
 256     UWORD to_unicode[256];
 257 };
 258
 259 #include "support.h"
 260
 261 /* new definitions as we refactor the code */
 262
 263 /* get the first sector of a cluster */
 264 #define SECTOR_FROM_CLUSTER(sb,cl) ((ULONG) (((cl-2) << sb->cluster_sectors_bits) + sb->first_data_sector))
 265
 266 #define FIRST_FILE_CLUSTER(de)                                       \
 267     (AROS_LE2WORD((de)->e.entry.first_cluster_lo) |                  \
 268      (((ULONG) AROS_LE2WORD((de)->e.entry.first_cluster_hi)) << 16))
 269
 270 #define RESET_HANDLE(ioh)                                          \
 271     do {                                                           \
 272         (ioh)->cluster_offset = (ioh)->sector_offset = 0xffffffff; \
 273         if ((ioh)->block != NULL) {                                \
 274             Cache_FreeBlock((ioh)->sb->cache, (ioh)->block);       \
 275             (ioh)->block = NULL;                                   \
 276         }                                                          \
 277     } while (0);
 278
 279 #define RESET_DIRHANDLE(dh)         \
 280     do {                            \
 281         RESET_HANDLE(&((dh)->ioh));   \
 282         (dh)->cur_index = 0xffffffff; \
 283     } while(0);
 284
 285 #define GET_NEXT_CLUSTER(sb,cl)     (sb->func_get_fat_entry(sb,cl))
 286 #define SET_NEXT_CLUSTER(sb,cl,val) (sb->func_set_fat_entry(sb,cl,val))
 287
 288 #define CALC_SHORT_NAME_CHECKSUM(name,checksum)                                 \
 289     do {                                                                        \
 290         ULONG i;                                                                \
 291         checksum = 0;                                                           \
 292         for (i = 0; i < 11; i++)                                                \
 293             checksum = ((checksum & 1) ? 0x80 : 0) + (checksum >> 1) + name[i]; \
 294     } while(0);
 295
 296 #define LOCKFROMNODE(A) \
 297     ((struct ExtFileLock *) \
 298     (((BYTE *)(A)) - (IPTR)&((struct ExtFileLock *)NULL)->node))
 299
 300 #endif