rom/filesys/fat/fat_fs.h

   1 /*
   2  * fat-handler - FAT12/16/32 filesystem handler
   3  *
   4  * Copyright © 2006 Marek Szyprowski
   5  * Copyright © 2007-2013 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 #if DEBUG_NAMES
 134     UBYTE shortname[13];                /* copy of the short name (bstr) */
 135 #endif
 136
 137     struct MinList      locks;          /* list of ExtFileLocks opened on this file */
 138 };
 139
 140 /* a node in the list of notification requests */
 141 struct NotifyNode {
 142     struct MinNode          node;
 143
 144     struct GlobalLock       *gl;        /* pointer to global lock if this file is
 145                                            locked. if it's not, this is NULL */
 146
 147     struct NotifyRequest    *nr;        /* the request that DOS passed us */
 148 };
 149
 150 struct VolumeInfo {
 151     APTR mem_pool;
 152     ULONG id;
 153     struct MinList locks;           /* global locks */
 154     struct GlobalLock root_lock;
 155     struct MinList notifies;
 156 };
 157
 158 struct VolumeIdentity {
 159     UBYTE               name[32];     /* BCPL string */
 160     struct DateStamp    create_time;
 161 };
 162
 163 struct FSSuper {
 164     struct Node node;
 165     struct DosList *doslist;
 166
 167     struct VolumeInfo *info;
 168
 169     struct cache *cache;
 170     ULONG        first_device_sector;
 171
 172     ULONG sectorsize;
 173     ULONG sectorsize_bits;
 174
 175     ULONG cluster_sectors;
 176     ULONG clustersize;
 177     ULONG clustersize_bits;
 178     ULONG cluster_sectors_bits;
 179
 180     ULONG first_fat_sector;
 181     ULONG first_data_sector;
 182     ULONG first_rootdir_sector;
 183
 184     ULONG rootdir_sectors;
 185     ULONG total_sectors;
 186     ULONG data_sectors;
 187     ULONG clusters_count;
 188     ULONG fat_size;
 189     UWORD fat_count;
 190
 191     ULONG free_clusters;
 192     ULONG next_cluster;
 193
 194     ULONG volume_id;
 195     ULONG type;
 196     ULONG eoc_mark;
 197
 198     APTR  *fat_blocks;
 199     UBYTE **fat_buffers;
 200     ULONG fat_blocks_count;
 201
 202     ULONG fat_cachesize;
 203     ULONG fat_cachesize_bits;
 204     ULONG fat_cache_block;
 205     UWORD fat_cache_no;    /* FAT number that cached FAT blocks belong to */
 206
 207     APTR fsinfo_block;
 208     struct FATFSInfo *fsinfo_buffer;
 209
 210     ULONG rootdir_cluster;
 211     ULONG rootdir_sector;
 212
 213     struct VolumeIdentity volume;
 214
 215     /* function table */
 216     ULONG (*func_get_fat_entry)(struct FSSuper *sb, ULONG n);
 217     void  (*func_set_fat_entry)(struct FSSuper *sb, ULONG n, ULONG val);
 218     /* ... */
 219 };
 220
 221 struct Globals {
 222     /* mem/task */
 223     struct Task *ourtask;
 224     struct MsgPort *ourport;
 225     APTR mempool;
 226
 227     struct MsgPort *notifyport;
 228
 229     /* fs */
 230     struct DosList *devnode;
 231     struct FileSysStartupMsg *fssm;
 232     LONG quit;
 233     struct DosPacket *death_packet;
 234     BOOL autodetect;
 235
 236     /* io */
 237     struct IOExtTD *diskioreq;
 238     struct IOExtTD *diskchgreq;
 239     struct MsgPort *diskport;
 240     ULONG diskchgsig_bit;
 241     struct timerequest *timereq;
 242     struct MsgPort *timerport;
 243     ULONG last_num;    /* last block number that was outside boundaries */
 244     UWORD readcmd;
 245     UWORD writecmd;
 246     char timer_active;
 247     char restart_timer;
 248
 249     /* volumes */
 250     struct FSSuper *sb;    /* current sb */
 251     struct MinList sblist;   /* sbs with outstanding locks or notifies */
 252
 253     /* disk status */
 254     LONG disk_inserted;
 255     LONG disk_inhibited;
 256
 257     /* Character sets translation */
 258     UBYTE from_unicode[65536];
 259     UWORD to_unicode[256];
 260 };
 261
 262 #include "support.h"
 263
 264 /* new definitions as we refactor the code */
 265
 266 /* get the first sector of a cluster */
 267 #define SECTOR_FROM_CLUSTER(sb,cl) ((ULONG) (((cl-2) << sb->cluster_sectors_bits) + sb->first_data_sector))
 268
 269 #define FIRST_FILE_CLUSTER(de)                                       \
 270     (AROS_LE2WORD((de)->e.entry.first_cluster_lo) |                  \
 271      (((ULONG) AROS_LE2WORD((de)->e.entry.first_cluster_hi)) << 16))
 272
 273 #define RESET_HANDLE(ioh)                                          \
 274     do {                                                           \
 275         (ioh)->cluster_offset = (ioh)->sector_offset = 0xffffffff; \
 276         if ((ioh)->block != NULL) {                                \
 277             Cache_FreeBlock((ioh)->sb->cache, (ioh)->block);       \
 278             (ioh)->block = NULL;                                   \
 279         }                                                          \
 280     } while (0);
 281
 282 #define RESET_DIRHANDLE(dh)         \
 283     do {                            \
 284         RESET_HANDLE(&((dh)->ioh));   \
 285         (dh)->cur_index = 0xffffffff; \
 286     } while(0);
 287
 288 #define GET_NEXT_CLUSTER(sb,cl)     (sb->func_get_fat_entry(sb,cl))
 289 #define SET_NEXT_CLUSTER(sb,cl,val) (sb->func_set_fat_entry(sb,cl,val))
 290
 291 #define CALC_SHORT_NAME_CHECKSUM(name,checksum)                                 \
 292     do {                                                                        \
 293         ULONG i;                                                                \
 294         checksum = 0;                                                           \
 295         for (i = 0; i < 11; i++)                                                \
 296             checksum = ((checksum & 1) ? 0x80 : 0) + (checksum >> 1) + name[i]; \
 297     } while(0);
 298
 299 #define LOCKFROMNODE(A) \
 300     ((struct ExtFileLock *) \
 301     (((BYTE *)(A)) - (IPTR)&((struct ExtFileLock *)NULL)->node))
 302
 303 #endif