rom/filesys/fat/fat_fs.h

   1 /*
   2  * fat-handler - FAT12/16/32 filesystem handler
   3  *
   4  * Copyright © 2006 Marek Szyprowski
   5  * Copyright © 2007-2018 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 <dos/dos.h>
  28 #include <exec/interrupts.h>
  29
  30 #include "fat_struct.h"
  31
  32 #include "cache.h"
  33
  34 /* Supported Filesystem Ids */
  35 #if !defined(ID_FAT12_DISK)
  36 #define ID_FAT12_DISK   0x46415400UL
  37 #endif
  38 #if !defined(ID_FAT16_DISK)
  39 #define ID_FAT16_DISK   0x46415401UL
  40 #endif
  41 #if !defined(ID_FAT32_DISK)
  42 #define ID_FAT32_DISK   0x46415402UL
  43 #endif
  44 #if !defined(ID_FAT_DISK)
  45 #define ID_FAT_DISK     ID_FAT12_DISK
  46 #endif
  47
  48 /* Filesystem structures */
  49
  50 #define ACTION_VOLUME_ADD 16000
  51 #define ACTION_VOLUME_REMOVE 16001
  52
  53 #define DEF_POOL_SIZE 65536
  54 #define DEF_POOL_THRESHOLD DEF_POOL_SIZE
  55
  56
  57 /* A handle on something, file or directory */
  58 struct IOHandle
  59 {
  60     struct FSSuper      *sb;            /* filesystem data */
  61
  62     ULONG               first_cluster;  /* first cluster of this file */
  63     ULONG               cur_cluster;    /* cluster that the current sector is within */
  64
  65     ULONG               cluster_offset; /* cluster number of this cluster within the current file */
  66
  67     ULONG               first_sector;   /* first sector in the first cluster, for fat12/16 root dir */
  68     ULONG               cur_sector;     /* sector number our block is currently in */
  69
  70     ULONG               sector_offset;  /* current sector as an offset in the current cluster
  71                                            i.e. cur = sector(cur_cluster) + offset */
  72
  73     APTR block;         /* current block from the cache */
  74     UBYTE *data;        /* current data buffer (from cache) */
  75 };
  76
  77 /* A handle on a directory */
  78 struct DirHandle
  79 {
  80     struct IOHandle     ioh;
  81
  82     ULONG               cur_index;      /* last entry returned, for GetNextDirEntry */
  83 };
  84
  85 /* Single directory entry */
  86 struct DirEntry
  87 {
  88     struct FSSuper      *sb;            /* filesystem data */
  89
  90     ULONG               cluster;        /* cluster the containing directory starts at */
  91     ULONG               index;          /* index of this entry */
  92
  93     ULONG               pos;            /* byte offset within directory that the entry came from */
  94
  95     union {
  96         struct FATDirEntry      entry;
  97         struct FATLongDirEntry  long_entry;
  98     } e;
  99 };
 100
 101 #define FAT_ROOTDIR_MARK    0xFFFFFFFFlu
 102
 103 struct GlobalLock;
 104
 105 struct ExtFileLock
 106 {
 107     /* struct FileLock */
 108     BPTR                fl_Link;
 109     IPTR                fl_Key;
 110     LONG                fl_Access;
 111     struct MsgPort *    fl_Task;
 112     BPTR                fl_Volume;
 113
 114     ULONG               magic;          /* we set this to ID_FAT_DISK so we can tell
 115                                            our locks from those of other filesystems */
 116
 117     struct MinNode      node;           /* node in the list of locks attached to the global lock */
 118     struct GlobalLock   *gl;            /* pointer to the global lock for this file */
 119
 120     struct IOHandle     ioh;            /* handle for reads and writes */
 121     ULONG               pos;            /* current seek position within the file */
 122
 123     BOOL                do_notify;      /* if set, send notification on file close (ACTION_END) */
 124     struct FSSuper      *sb;            /* pointer to sb, for unlocking when volume is removed */
 125 };
 126
 127 struct GlobalLock
 128 {
 129     struct MinNode      node;
 130
 131     ULONG               dir_cluster;    /* first cluster of the directory we're in */
 132     ULONG               dir_entry;      /* this is our dir entry within dir_cluster */
 133
 134     LONG                access;         /* access mode, shared or exclusive */
 135
 136     ULONG               first_cluster;  /* first data cluster */
 137
 138     ULONG               attr;           /* file attributes, from the dir entry */
 139     ULONG               size;           /* file size, from the dir entry */
 140
 141     UBYTE name[FAT_MAX_LONG_FILENAME];  /* copy of the name (bstr) */
 142 #if DEBUG_NAMES
 143     UBYTE shortname[FAT_MAX_SHORT_NAME + 2]; /* copy of the short name (bstr) */
 144 #endif
 145
 146     struct MinList      locks;          /* list of ExtFileLocks opened on this file */
 147 };
 148
 149 /* A node in the list of notification requests */
 150 struct NotifyNode
 151 {
 152     struct MinNode          node;
 153
 154     struct GlobalLock       *gl;        /* pointer to global lock if this file is
 155                                            locked. if it's not, this is NULL */
 156
 157     struct NotifyRequest    *nr;        /* the request that DOS passed us */
 158 };
 159
 160 struct VolumeInfo
 161 {
 162     APTR mem_pool;
 163     ULONG id;
 164     struct MinList locks;           /* global locks */
 165     struct GlobalLock root_lock;
 166     struct MinList notifies;
 167 };
 168
 169 struct VolumeIdentity
 170 {
 171     UBYTE               name[FAT_MAX_SHORT_NAME + 2];     /* BCPL string */
 172     struct DateStamp    create_time;
 173 };
 174
 175 struct FSSuper
 176 {
 177     struct Node node;
 178
 179     struct Globals *glob;
 180     struct DosList *doslist;
 181
 182     struct VolumeInfo *info;
 183
 184     struct cache *cache;
 185     ULONG first_device_sector;
 186
 187     ULONG sectorsize;
 188     ULONG sectorsize_bits;
 189
 190     ULONG cluster_sectors;
 191     ULONG clustersize;
 192     ULONG clustersize_bits;
 193     ULONG cluster_sectors_bits;
 194
 195     ULONG first_fat_sector;
 196     ULONG first_data_sector;
 197     ULONG first_rootdir_sector;
 198
 199     ULONG rootdir_sectors;
 200     ULONG total_sectors;
 201     ULONG data_sectors;
 202     ULONG clusters_count;
 203     ULONG fat_size;
 204     UWORD fat_count;
 205
 206     ULONG free_clusters;
 207     ULONG next_cluster;
 208
 209     ULONG volume_id;
 210     ULONG type;
 211     ULONG eoc_mark;
 212
 213     APTR  *fat_blocks;
 214     UBYTE **fat_buffers;
 215     ULONG fat_blocks_count;
 216
 217     ULONG fat_cachesize;
 218     ULONG fat_cachesize_bits;
 219     ULONG fat_cache_block;
 220     UWORD fat_cache_no;    /* FAT number that cached FAT blocks belong to */
 221
 222     APTR fsinfo_block;
 223     struct FATFSInfo *fsinfo_buffer;
 224
 225     ULONG rootdir_cluster;
 226     ULONG rootdir_sector;
 227
 228     struct VolumeIdentity volume;
 229
 230     /* function table */
 231     ULONG (*func_get_fat_entry)(struct FSSuper *sb, ULONG n);
 232     BOOL (*func_set_fat_entry)(struct FSSuper *sb, ULONG n, ULONG val);
 233     /* ... */
 234 };
 235
 236 struct Globals
 237 {
 238     /* Libraries */
 239     struct ExecBase *gl_SysBase;
 240     struct DosLibrary *gl_DOSBase;
 241     struct Library *gl_UtilityBase;
 242     struct Device *gl_TimerBase;
 243
 244     /* mem/task */
 245     struct Task *ourtask;
 246     struct MsgPort *ourport;
 247     APTR mempool;
 248
 249     struct MsgPort *notifyport;
 250
 251     /* fs */
 252     struct DosList *devnode;
 253     struct FileSysStartupMsg *fssm;
 254     BOOL quit;
 255     struct DosPacket *death_packet;
 256     BOOL autodetect;
 257
 258     /* io */
 259     struct IOExtTD *diskioreq;
 260     struct IOExtTD *diskchgreq;
 261     struct MsgPort *diskport;
 262     ULONG diskchgsig_bit;
 263     struct timerequest *timereq;
 264     struct MsgPort *timerport;
 265     ULONG last_num;    /* last block number that was outside boundaries */
 266     UWORD readcmd;
 267     UWORD writecmd;
 268     BOOL timer_active;
 269     BOOL restart_timer;
 270
 271     /* volumes */
 272     struct FSSuper *sb;    /* current sb */
 273     struct MinList sblist;   /* sbs with outstanding locks or notifies */
 274
 275     /* disk status */
 276     LONG disk_inhibited;
 277     BOOL disk_inserted;
 278     BOOL formatting;
 279
 280     /* Character sets translation */
 281     UBYTE from_unicode[65536];
 282     UWORD to_unicode[256];
 283
 284     /* Disk change interrupt */
 285     struct IntData {
 286         struct Interrupt Interrupt;
 287         struct ExecBase *SysBase;
 288         struct Task *task;
 289         ULONG signal;
 290     } DiskChangeIntData;
 291 };
 292
 293 #define DOSBase (glob->gl_DOSBase)
 294 #define SysBase (glob->gl_SysBase)
 295 #define UtilityBase (glob->gl_UtilityBase)
 296 #define TimerBase (glob->gl_TimerBase)
 297
 298 #include "support.h"
 299
 300 /* Get the first sector of a cluster */
 301 #define SECTOR_FROM_CLUSTER(sb,cl) \
 302     ((ULONG) (((cl-2) << sb->cluster_sectors_bits) + sb->first_data_sector))
 303
 304 #define FIRST_FILE_CLUSTER(de) \
 305     (AROS_LE2WORD((de)->e.entry.first_cluster_lo) | \
 306      (((ULONG) AROS_LE2WORD((de)->e.entry.first_cluster_hi)) << 16))
 307
 308 #define RESET_HANDLE(ioh) \
 309     do \
 310     { \
 311         (ioh)->cluster_offset = (ioh)->sector_offset = 0xffffffff; \
 312         if ((ioh)->block != NULL) \
 313         { \
 314             Cache_FreeBlock((ioh)->sb->cache, (ioh)->block); \
 315             (ioh)->block = NULL; \
 316         } \
 317     } \
 318     while (0);
 319
 320 #define RESET_DIRHANDLE(dh) \
 321     do \
 322     { \
 323         RESET_HANDLE(&((dh)->ioh)); \
 324         (dh)->cur_index = 0xffffffff; \
 325     } \
 326     while(0);
 327
 328 #define GET_NEXT_CLUSTER(sb,cl)     (sb->func_get_fat_entry(sb,cl))
 329 #define SET_NEXT_CLUSTER(sb,cl,val) (sb->func_set_fat_entry(sb,cl,val))
 330
 331 #define CALC_SHORT_NAME_CHECKSUM(name,checksum) \
 332     do \
 333     { \
 334         ULONG i; \
 335         checksum = 0; \
 336         for (i = 0; i < FAT_MAX_SHORT_NAME; i++) \
 337             checksum = \
 338                 ((checksum & 1) ? 0x80 : 0) + (checksum >> 1) + name[i]; \
 339     } \
 340     while(0);
 341
 342 #define LOCKFROMNODE(A) \
 343     ((struct ExtFileLock *) \
 344     (((BYTE *)(A)) - (IPTR)&((struct ExtFileLock *)NULL)->node))
 345
 346 #endif