2 * fat-handler - FAT12/16/32 filesystem handler
4 * Copyright © 2006 Marek Szyprowski
5 * Copyright © 2007-2015 The AROS Development Team
7 * This program is free software; you can redistribute it and/or modify it
8 * under the same terms as AROS itself.
13 #include <aros/macros.h>
14 #include <exec/errors.h>
15 #include <exec/types.h>
17 #include <dos/dosextens.h>
18 #include <dos/filehandler.h>
20 #include <proto/exec.h>
21 #include <proto/dos.h>
22 #include <proto/utility.h>
23 #include <proto/timer.h>
24 #include <clib/alib_protos.h>
26 #include <clib/macros.h>
32 #include "fat_protos.h"
34 #define DEBUG DEBUG_MISC
37 static const UBYTE default_oem_name
[] = "MSWIN4.1";
38 static const UBYTE default_filsystype
[] = "FAT16 ";
40 static const ULONG fat16_cluster_thresholds
[] =
50 static const ULONG fat32_cluster_thresholds
[] =
58 /* helper function to get the location of a fat entry for a cluster. it used
59 * to be a define until it got too crazy */
60 static UBYTE
*GetFatEntryPtr(struct FSSuper
*sb
, ULONG offset
, APTR
*rb
,
62 ULONG entry_cache_block
= offset
>> sb
->fat_cachesize_bits
;
63 ULONG entry_cache_offset
= offset
& (sb
->fat_cachesize
- 1);
67 /* if the target cluster is not within the currently loaded chunk of fat,
68 * we need to get the right data in */
69 if (sb
->fat_cache_block
!= entry_cache_block
70 || sb
->fat_cache_no
!= fat_no
) {
71 D(bug("[fat] loading %ld FAT sectors starting at sector %ld\n", sb
->fat_blocks_count
, entry_cache_block
<< (sb
->fat_cachesize_bits
- sb
->sectorsize_bits
)));
72 /* put the old ones back */
73 if (sb
->fat_cache_block
!= 0xffffffff)
74 for (i
= 0; i
< sb
->fat_blocks_count
; i
++)
75 Cache_FreeBlock(sb
->cache
, sb
->fat_blocks
[i
]);
78 num
= sb
->first_device_sector
+ sb
->first_fat_sector
79 + sb
->fat_size
* fat_no
+ (entry_cache_block
80 << (sb
->fat_cachesize_bits
- sb
->sectorsize_bits
));
81 for (i
= 0; i
< sb
->fat_blocks_count
; i
++)
83 Cache_GetBlock(sb
->cache
, num
+ i
, &sb
->fat_buffers
[i
]);
85 /* remember where we are for next time */
86 sb
->fat_cache_block
= entry_cache_block
;
87 sb
->fat_cache_no
= fat_no
;
90 /* give the block back if they asked for it (needed to mark the block
91 * dirty if they're writing) */
93 *rb
= sb
->fat_blocks
[entry_cache_offset
>> sb
->sectorsize_bits
];
95 /* compute the pointer location and return it */
96 return sb
->fat_buffers
[entry_cache_offset
>> sb
->sectorsize_bits
] +
97 (entry_cache_offset
& (sb
->sectorsize
- 1));
100 /* FAT12 has, as the name suggests, 12-bit FAT entries. This means that two
101 * entries are condensed into three bytes, like so:
103 * entry: aaaaaaaa aaaabbbb bbbbbbbb
104 * bytes: xxxxxxxx xxxxxxxx xxxxxxxx
106 * To get at the entry we want, we find and grab the word starting at either
107 * byte 0 or 1 of the three-byte set, then shift up or down as needed. FATdoc
108 * 1.03 p16-17 describes the method
110 * The only tricky bit is if the word falls such that the first byte is the
111 * last byte of the block and the second byte is the first byte of the next
112 * block. Since our block data are stored within cache block structures, a
113 * simple cast won't do (hell, the second block may not even be in memory if
114 * we're at the end of the FAT cache). So we get it a byte at a time, and
115 * build the word ourselves.
117 static ULONG
GetFat12Entry(struct FSSuper
*sb
, ULONG n
) {
118 ULONG offset
= n
+ n
/2;
121 if ((offset
& (sb
->sectorsize
-1)) == sb
->sectorsize
-1) {
122 D(bug("[fat] fat12 cluster pair on block boundary, compensating\n"));
124 val
= *GetFatEntryPtr(sb
, offset
+ 1, NULL
, 0) << 8;
125 val
|= *GetFatEntryPtr(sb
, offset
, NULL
, 0);
128 val
= AROS_LE2WORD(*((UWORD
*) GetFatEntryPtr(sb
, offset
, NULL
, 0)));
139 * FAT16 and FAT32, on the other hand, have nice neat entry widths, so simple
140 * word/long casts are fine. There's also no chance that the entry can be
141 * split across blocks. Why can't everything be this simple?
143 static ULONG
GetFat16Entry(struct FSSuper
*sb
, ULONG n
) {
144 return AROS_LE2WORD(*((UWORD
*) GetFatEntryPtr(sb
, n
<< 1, NULL
, 0)));
147 static ULONG
GetFat32Entry(struct FSSuper
*sb
, ULONG n
) {
148 return AROS_LE2LONG(*((ULONG
*) GetFatEntryPtr(sb
, n
<< 2, NULL
, 0)))
152 static void SetFat12Entry(struct FSSuper
*sb
, ULONG n
, ULONG val
) {
154 ULONG offset
= n
+ n
/2;
155 BOOL boundary
= FALSE
;
156 UWORD
*fat
= NULL
, newval
, i
;
158 for (i
= 0; i
< sb
->fat_count
; i
++)
160 if ((offset
& (sb
->sectorsize
-1)) == sb
->sectorsize
-1) {
163 D(bug("[fat] fat12 cluster pair on block boundary, compensating\n"));
165 newval
= *GetFatEntryPtr(sb
, offset
+ 1, NULL
, i
) << 8;
166 newval
|= *GetFatEntryPtr(sb
, offset
, NULL
, i
);
169 fat
= (UWORD
*) GetFatEntryPtr(sb
, offset
, &b
, i
);
170 newval
= AROS_LE2WORD(*fat
);
175 newval
= (newval
& 0xf) | val
;
178 newval
= (newval
& 0xf000) | val
;
182 /* XXX ideally we'd mark both blocks dirty at the same time or
183 * only do it once if they're the same block. unfortunately any
184 * old value of b is invalid after a call to GetFatEntryPtr, as
185 * it may have swapped the previous cache out. This is probably
187 *GetFatEntryPtr(sb
, offset
+1, &b
, i
) = newval
>> 8;
188 Cache_MarkBlockDirty(sb
->cache
, b
);
189 *GetFatEntryPtr(sb
, offset
, &b
, i
) = newval
& 0xff;
190 Cache_MarkBlockDirty(sb
->cache
, b
);
193 *fat
= AROS_WORD2LE(newval
);
194 Cache_MarkBlockDirty(sb
->cache
, b
);
199 static void SetFat16Entry(struct FSSuper
*sb
, ULONG n
, ULONG val
) {
203 for (i
= 0; i
< sb
->fat_count
; i
++)
205 *((UWORD
*) GetFatEntryPtr(sb
, n
<< 1, &b
, i
)) =
206 AROS_WORD2LE((UWORD
) val
);
207 Cache_MarkBlockDirty(sb
->cache
, b
);
211 static void SetFat32Entry(struct FSSuper
*sb
, ULONG n
, ULONG val
) {
216 for (i
= 0; i
< sb
->fat_count
; i
++)
218 fat
= (ULONG
*) GetFatEntryPtr(sb
, n
<< 2, &b
, i
);
220 *fat
= (*fat
& 0xf0000000) | val
;
222 Cache_MarkBlockDirty(sb
->cache
, b
);
226 LONG
ReadFATSuper(struct FSSuper
*sb
) {
227 struct DosEnvec
*de
= BADDR(glob
->fssm
->fssm_Environ
);
229 ULONG bsize
= de
->de_SizeBlock
* 4, total_sectors
;
230 struct FATBootSector
*boot
;
231 struct FATEBPB
*ebpb
;
232 struct FATFSInfo
*fsinfo
;
233 BOOL invalid
= FALSE
;
237 struct DirEntry dir_entry
;
241 D(bug("[fat] reading boot sector\n"));
243 boot
= AllocMem(bsize
, MEMF_ANY
);
245 return ERROR_NO_FREE_STORE
;
247 sb
->first_device_sector
=
248 de
->de_BlocksPerTrack
* de
->de_Surfaces
* de
->de_LowCyl
;
250 /* Get a preliminary total-sectors value so we don't risk going outside
251 * partition limits */
253 de
->de_BlocksPerTrack
* de
->de_Surfaces
* (de
->de_HighCyl
+ 1)
254 - sb
->first_device_sector
;
256 D(bug("[fat] boot sector at sector %ld\n", sb
->first_device_sector
));
259 * Read the boot sector. We go direct because we don't have a cache yet,
260 * and can't create one until we know the sector size, which is held in
261 * the boot sector. In practice it doesn't matter - we're going to use
262 * this once and once only.
264 if ((err
= AccessDisk(FALSE
, sb
->first_device_sector
, 1, bsize
, (UBYTE
*)boot
)) != 0) {
265 D(bug("[fat] couldn't read boot block (%ld)\n", err
));
266 FreeMem(boot
, bsize
);
270 D(bug("\tBoot sector:\n"));
272 sb
->sectorsize
= AROS_LE2WORD(boot
->bpb_bytes_per_sect
);
273 sb
->sectorsize_bits
= log2(sb
->sectorsize
);
274 D(bug("\tSectorSize = %ld\n", sb
->sectorsize
));
275 D(bug("\tSectorSize Bits = %ld\n", sb
->sectorsize_bits
));
277 sb
->cluster_sectors
= boot
->bpb_sect_per_clust
;
278 sb
->clustersize
= sb
->sectorsize
* boot
->bpb_sect_per_clust
;
279 sb
->clustersize_bits
= log2(sb
->clustersize
);
280 sb
->cluster_sectors_bits
= sb
->clustersize_bits
- sb
->sectorsize_bits
;
282 D(bug("\tSectorsPerCluster = %ld\n", (ULONG
)boot
->bpb_sect_per_clust
));
283 D(bug("\tClusterSize = %ld\n", sb
->clustersize
));
284 D(bug("\tClusterSize Bits = %ld\n", sb
->clustersize_bits
));
285 D(bug("\tCluster Sectors Bits = %ld\n", sb
->cluster_sectors_bits
));
287 sb
->first_fat_sector
= AROS_LE2WORD(boot
->bpb_rsvd_sect_count
);
288 D(bug("\tFirst FAT Sector = %ld\n", sb
->first_fat_sector
));
290 sb
->fat_count
= boot
->bpb_num_fats
;
291 D(bug("\tNumber of FATs = %d\n", sb
->fat_count
));
293 if (boot
->bpb_fat_size_16
!= 0)
294 sb
->fat_size
= AROS_LE2WORD(boot
->bpb_fat_size_16
);
296 sb
->fat_size
= AROS_LE2LONG(boot
->ebpbs
.ebpb32
.bpb_fat_size_32
);
297 D(bug("\tFAT Size = %ld\n", sb
->fat_size
));
299 if (boot
->bpb_total_sectors_16
!= 0)
300 total_sectors
= AROS_LE2WORD(boot
->bpb_total_sectors_16
);
302 total_sectors
= AROS_LE2LONG(boot
->bpb_total_sectors_32
);
303 D(bug("\tTotal Sectors = %ld\n", sb
->total_sectors
));
305 /* Check that the boot block's sector count is the same as the
306 * partition's sector count. This stops a resized partition being
307 * mounted before reformatting */
308 if (total_sectors
!= sb
->total_sectors
)
311 sb
->rootdir_sectors
= ((AROS_LE2WORD(boot
->bpb_root_entries_count
) * sizeof(struct FATDirEntry
)) + (sb
->sectorsize
- 1)) >> sb
->sectorsize_bits
;
312 D(bug("\tRootDir Sectors = %ld\n", sb
->rootdir_sectors
));
314 sb
->data_sectors
= sb
->total_sectors
- (sb
->first_fat_sector
+ (sb
->fat_count
* sb
->fat_size
) + sb
->rootdir_sectors
);
315 D(bug("\tData Sectors = %ld\n", sb
->data_sectors
));
317 sb
->clusters_count
= sb
->data_sectors
>> sb
->cluster_sectors_bits
;
318 D(bug("\tClusters Count = %ld\n", sb
->clusters_count
));
320 sb
->first_rootdir_sector
= sb
->first_fat_sector
+ (sb
->fat_count
* sb
->fat_size
);
321 D(bug("\tFirst RootDir Sector = %ld\n", sb
->first_rootdir_sector
));
323 sb
->first_data_sector
= sb
->first_fat_sector
+ (sb
->fat_count
* sb
->fat_size
) + sb
->rootdir_sectors
;
324 D(bug("\tFirst Data Sector = %ld\n", sb
->first_data_sector
));
326 /* check if disk is in fact a FAT filesystem */
328 /* valid sector size: 512, 1024, 2048, 4096 */
329 if (sb
->sectorsize
!= 512 && sb
->sectorsize
!= 1024 && sb
->sectorsize
!= 2048 && sb
->sectorsize
!= 4096)
332 /* valid bpb_sect_per_clust: 1, 2, 4, 8, 16, 32, 64, 128 */
333 if ((boot
->bpb_sect_per_clust
& (boot
->bpb_sect_per_clust
- 1)) != 0 || boot
->bpb_sect_per_clust
== 0 || boot
->bpb_sect_per_clust
> 128)
336 /* valid cluster size: 512, 1024, 2048, 4096, 8192, 16k, 32k, 64k */
337 if (sb
->clustersize
> 64 * 1024)
340 if (sb
->first_fat_sector
== 0)
343 if (sb
->fat_count
== 0)
346 if (boot
->bpb_media
< 0xF0)
349 /* FAT "signature" */
350 if (boot
->bpb_signature
[0] != 0x55 || boot
->bpb_signature
[1] != 0xaa)
354 D(bug("\tInvalid FAT Boot Sector\n"));
355 FreeMem(boot
, bsize
);
356 return ERROR_NOT_A_DOS_DISK
;
358 end
= 0xFFFFFFFF / sb
->sectorsize
;
359 if ((sb
->first_device_sector
+ sb
->total_sectors
- 1 > end
) && (glob
->readcmd
== CMD_READ
)) {
360 D(bug("\tDevice is too large\n"));
361 FreeMem(boot
, bsize
);
362 return IOERR_BADADDRESS
;
365 sb
->cache
= Cache_CreateCache(64, 64, sb
->sectorsize
);
367 if (sb
->clusters_count
< 4085) {
368 D(bug("\tFAT12 filesystem detected\n"));
370 sb
->eoc_mark
= 0x0FFF;
371 sb
->func_get_fat_entry
= GetFat12Entry
;
372 sb
->func_set_fat_entry
= SetFat12Entry
;
374 else if (sb
->clusters_count
< 65525) {
375 D(bug("\tFAT16 filesystem detected\n"));
377 sb
->eoc_mark
= 0xFFFF;
378 sb
->func_get_fat_entry
= GetFat16Entry
;
379 sb
->func_set_fat_entry
= SetFat16Entry
;
382 D(bug("\tFAT32 filesystem detected\n"));
384 sb
->eoc_mark
= 0x0FFFFFFF;
385 sb
->func_get_fat_entry
= GetFat32Entry
;
386 sb
->func_set_fat_entry
= SetFat32Entry
;
390 /* setup the FAT cache and load the first blocks */
391 sb
->fat_cachesize
= 4096;
392 sb
->fat_cachesize_bits
= log2(sb
->fat_cachesize
);
393 sb
->fat_cache_block
= 0xffffffff;
395 sb
->fat_blocks_count
=
396 MIN(sb
->fat_size
, sb
->fat_cachesize
>> sb
->sectorsize_bits
);
397 sb
->fat_blocks
= AllocVecPooled(glob
->mempool
,
398 sizeof(APTR
) * sb
->fat_blocks_count
);
399 sb
->fat_buffers
= AllocVecPooled(glob
->mempool
,
400 sizeof(APTR
) * sb
->fat_blocks_count
);
402 if (sb
->type
!= 32) { /* FAT 12/16 */
403 /* setup volume id */
404 sb
->volume_id
= AROS_LE2LONG(boot
->ebpbs
.ebpb
.bs_volid
);
406 /* location of root directory */
407 sb
->rootdir_cluster
= 0;
408 sb
->rootdir_sector
= sb
->first_rootdir_sector
;
409 ebpb
= &boot
->ebpbs
.ebpb
;
412 /* setup volume id */
413 sb
->volume_id
= AROS_LE2LONG(boot
->ebpbs
.ebpb32
.ebpb
.bs_volid
);
415 /* location of root directory */
416 sb
->rootdir_cluster
= AROS_LE2LONG(boot
->ebpbs
.ebpb32
.bpb_root_cluster
);
417 sb
->rootdir_sector
= 0;
418 ebpb
= &boot
->ebpbs
.ebpb32
.ebpb
;
421 D(bug("[fat] rootdir at cluster %ld sector %ld\n", sb
->rootdir_cluster
, sb
->rootdir_sector
));
423 /* Initialise the root directory if this is a newly formatted volume */
424 if (glob
->formatting
)
426 /* Clear all FAT sectors */
427 for (i
= 0; i
< sb
->fat_size
* 2; i
++) {
428 block_ref
= Cache_GetBlock(sb
->cache
,
429 sb
->first_device_sector
+ sb
->first_fat_sector
+ i
,
431 memset(fat_block
, 0, bsize
);
433 /* The first two entries are special */
435 *(UQUAD
*)fat_block
= AROS_QUAD2LE(0x0FFFFFFF0FFFFFF8);
436 else if (sb
->type
== 16)
437 *(ULONG
*)fat_block
= AROS_LONG2LE(0xFFFFFFF8);
439 *(ULONG
*)fat_block
= AROS_LONG2LE(0x00FFFFF8);
441 Cache_MarkBlockDirty(sb
->cache
, block_ref
);
442 Cache_FreeBlock(sb
->cache
, block_ref
);
445 /* allocate first cluster of the root directory */
447 AllocCluster(sb
, sb
->rootdir_cluster
);
449 /* get a handle on the root directory */
450 InitDirHandle(sb
, 0, &dh
, FALSE
);
452 /* clear all entries */
453 for (i
= 0; GetDirEntry(&dh
, i
, &dir_entry
) == 0; i
++) {
454 memset(&dir_entry
.e
.entry
, 0, sizeof(struct FATDirEntry
));
455 UpdateDirEntry(&dir_entry
);
458 SetVolumeName(sb
, ebpb
->bs_vollab
, 11);
460 ReleaseDirHandle(&dh
);
461 glob
->formatting
= FALSE
;
462 D(bug("\tRoot dir created.\n"));
465 if (GetVolumeIdentity(sb
, &(sb
->volume
)) != 0) {
467 UBYTE
*uu
= (void *)&sb
->volume_id
;
469 /* No volume name entry, so construct name from serial number */
474 sb
->volume
.name
[i
++]='-';
477 sb
->volume
.name
[i
++] = (d
< 10) ? '0' + d
: 'A' - 10 + d
;
478 d
= ((*uu
) & 0xf0)>>4;
479 sb
->volume
.name
[i
++] = (d
< 10) ? '0' + d
: 'A' - 10 + d
;
484 sb
->volume
.name
[i
] = '\0';
485 sb
->volume
.name
[0] = 9;
488 /* get initial number of free clusters */
489 sb
->free_clusters
= -1;
490 sb
->next_cluster
= -1;
491 if (sb
->type
== 32) {
492 sb
->fsinfo_block
= Cache_GetBlock(sb
->cache
, sb
->first_device_sector
493 + AROS_LE2WORD(boot
->ebpbs
.ebpb32
.bpb_fs_info
), (UBYTE
**)&fsinfo
);
494 if (sb
->fsinfo_block
!= NULL
) {
495 if (fsinfo
->lead_sig
== AROS_LONG2LE(FSI_LEAD_SIG
)
496 && fsinfo
->struct_sig
== AROS_LONG2LE(FSI_STRUCT_SIG
)
497 && fsinfo
->trail_sig
== AROS_LONG2LE(FSI_TRAIL_SIG
)) {
498 sb
->free_clusters
= AROS_LE2LONG(fsinfo
->free_count
);
499 sb
->next_cluster
= AROS_LE2LONG(fsinfo
->next_free
);
500 D(bug("[fat] valid FATFSInfo block found\n"));
501 sb
->fsinfo_buffer
= fsinfo
;
504 Cache_FreeBlock(sb
->cache
, sb
->fsinfo_block
);
507 if (sb
->free_clusters
== -1)
508 CountFreeClusters(sb
);
509 if (sb
->next_cluster
== -1)
510 sb
->next_cluster
= 2;
512 D(bug("\tFAT Filesystem successfully detected.\n"));
513 D(bug("\tFree Clusters = %ld\n", sb
->free_clusters
));
514 D(bug("\tNext Free Cluster = %ld\n", sb
->next_cluster
));
515 FreeMem(boot
, bsize
);
519 LONG
GetVolumeIdentity(struct FSSuper
*sb
, struct VolumeIdentity
*volume
) {
525 D(bug("[fat] searching root directory for volume name\n"));
527 /* search the directory for the volume id entry. it would've been nice to
528 * just use GetNextDirEntry but I didn't want a flag or something to tell
529 * it not to skip the volume name */
530 InitDirHandle(sb
, sb
->rootdir_cluster
, &dh
, FALSE
);
532 while ((err
= GetDirEntry(&dh
, dh
.cur_index
+ 1, &de
)) == 0) {
534 /* match the volume id entry */
535 if ((de
.e
.entry
.attr
& ATTR_VOLUME_ID_MASK
) == ATTR_VOLUME_ID
536 && de
.e
.entry
.name
[0] != 0xe5) {
537 D(bug("[fat] found volume id entry %ld\n", dh
.cur_index
));
539 /* copy the name in. volume->name is a BSTR */
541 volume
->name
[1] = de
.e
.entry
.name
[0];
543 for (i
= 1; i
< 11; i
++) {
544 if (volume
->name
[i
] == ' ')
545 volume
->name
[i
+1] = de
.e
.entry
.name
[i
];
547 volume
->name
[i
+1] = tolower(de
.e
.entry
.name
[i
]);
550 for (i
= 10; volume
->name
[i
+1] == ' '; i
--);
551 volume
->name
[i
+2] = '\0';
552 volume
->name
[0] = strlen(&(volume
->name
[1]));
554 /* get the volume creation date too */
555 ConvertFATDate(de
.e
.entry
.create_date
, de
.e
.entry
.create_time
, &volume
->create_time
);
557 D(bug("[fat] volume name is '%s'\n", &(volume
->name
[1])));
562 /* bail out if we hit the end of the dir */
563 if (de
.e
.entry
.name
[0] == 0x00) {
564 D(bug("[fat] found end-of-directory marker, volume name entry not found\n"));
565 err
= ERROR_OBJECT_NOT_FOUND
;
570 ReleaseDirHandle(&dh
);
574 LONG
FormatFATVolume(const UBYTE
*name
, UWORD len
) {
575 struct DosEnvec
*de
= BADDR(glob
->fssm
->fssm_Environ
);
577 ULONG bsize
= de
->de_SizeBlock
* 4;
578 struct FATBootSector
*boot
;
579 struct FATEBPB
*ebpb
;
580 struct FATFSInfo
*fsinfo
;
581 UWORD type
, i
, root_entries_count
;
582 struct EClockVal eclock
;
583 ULONG sectors_per_cluster
= 0, sector_count
, first_fat_sector
,
584 fat_size
, root_dir_sectors
, first_device_sector
, temp1
, temp2
;
586 /* Decide on FAT type based on number of sectors */
587 sector_count
= (de
->de_HighCyl
- de
->de_LowCyl
+ 1)
588 * de
->de_Surfaces
* de
->de_BlocksPerTrack
;
589 if (sector_count
< 4085)
591 else if (sector_count
< 1024 * 1024)
596 D(bug("[fat] writing boot sector\n"));
598 /* Decide on cluster size and root dir entries */
599 first_fat_sector
= 1;
601 if (sector_count
== 1440) {
602 sectors_per_cluster
= 2;
603 root_entries_count
= 112;
604 } else if (sector_count
== 2880) {
605 sectors_per_cluster
= 1;
606 root_entries_count
= 224;
607 } else if (sector_count
== 5760) {
608 sectors_per_cluster
= 2;
609 root_entries_count
= 240;
611 /* We only support some common 3.5" floppy formats */
612 return ERROR_NOT_IMPLEMENTED
;
614 } else if (type
== 16) {
615 for (i
= 0; fat16_cluster_thresholds
[i
] < sector_count
; i
++);
616 sectors_per_cluster
= 1 << i
;
617 root_entries_count
= 512;
619 for (i
= 0; fat32_cluster_thresholds
[i
] < sector_count
; i
++);
620 sectors_per_cluster
= 8 << i
;
621 root_entries_count
= 0;
622 first_fat_sector
= 32;
625 D(bug("\tFirst FAT Sector = %ld\n", first_fat_sector
));
627 /* Determine FAT size */
628 root_dir_sectors
= (root_entries_count
* 32 + (bsize
- 1)) / bsize
;
629 temp1
= sector_count
- (first_fat_sector
+ root_dir_sectors
);
630 temp2
= 256 * sectors_per_cluster
+ 2;
633 fat_size
= (temp1
+ temp2
- 1) / temp2
;
635 boot
= AllocMem(bsize
, MEMF_CLEAR
);
637 return ERROR_NO_FREE_STORE
;
639 /* Install x86 infinite loop boot code to keep major OSes happy */
640 boot
->bs_jmp_boot
[0] = 0xEB;
641 boot
->bs_jmp_boot
[1] = 0xFE;
642 boot
->bs_jmp_boot
[2] = 0x90;
644 CopyMem(default_oem_name
, boot
->bs_oem_name
, 8);
646 boot
->bpb_bytes_per_sect
= AROS_WORD2LE(bsize
);
647 boot
->bpb_sect_per_clust
= sectors_per_cluster
;
649 boot
->bpb_rsvd_sect_count
= AROS_WORD2LE(first_fat_sector
);
651 boot
->bpb_num_fats
= 2;
653 boot
->bpb_root_entries_count
= AROS_WORD2LE(root_entries_count
);
655 if (sector_count
< 0x10000 && type
!= 32)
656 boot
->bpb_total_sectors_16
= AROS_WORD2LE(sector_count
);
658 boot
->bpb_total_sectors_32
= AROS_LONG2LE(sector_count
);
660 boot
->bpb_media
= 0xF8;
662 boot
->bpb_sect_per_track
= AROS_WORD2LE(de
->de_BlocksPerTrack
);
663 boot
->bpb_num_heads
= AROS_WORD2LE(de
->de_Surfaces
);
664 boot
->bpb_hidden_sect
= AROS_LONG2LE(de
->de_Reserved
);
667 boot
->ebpbs
.ebpb32
.bpb_fat_size_32
= AROS_LONG2LE(fat_size
);
668 boot
->ebpbs
.ebpb32
.bpb_root_cluster
= AROS_LONG2LE(2);
669 boot
->ebpbs
.ebpb32
.bpb_fs_info
= AROS_WORD2LE(1);
670 boot
->ebpbs
.ebpb32
.bpb_back_bootsec
= AROS_WORD2LE(6);
671 ebpb
= &boot
->ebpbs
.ebpb32
.ebpb
;
674 boot
->bpb_fat_size_16
= AROS_WORD2LE(fat_size
);
675 ebpb
= &boot
->ebpbs
.ebpb
;
678 ebpb
->bs_drvnum
= 0x80;
679 ebpb
->bs_bootsig
= 0x29;
681 /* Generate a pseudo-random serial number. Not the original algorithm,
682 * but it shouldn't matter */
684 ebpb
->bs_volid
= FastRand(eclock
.ev_lo
^ eclock
.ev_hi
);
686 /* copy volume name in */
687 for (i
= 0; i
< 11; i
++)
689 ebpb
->bs_vollab
[i
] = toupper(name
[i
]);
691 ebpb
->bs_vollab
[i
] = ' ';
693 CopyMem(default_filsystype
, ebpb
->bs_filsystype
, 8);
696 ebpb
->bs_filsystype
[3] = '3';
697 ebpb
->bs_filsystype
[4] = '2';
700 boot
->bpb_signature
[0] = 0x55;
701 boot
->bpb_signature
[1] = 0xaa;
703 /* Write the boot sector */
704 first_device_sector
=
705 de
->de_BlocksPerTrack
* de
->de_Surfaces
* de
->de_LowCyl
;
707 D(bug("[fat] boot sector at sector %ld\n", first_device_sector
));
709 if ((err
= AccessDisk(TRUE
, first_device_sector
, 1, bsize
, (UBYTE
*)boot
)) != 0) {
710 D(bug("[fat] couldn't write boot block (%ld)\n", err
));
711 FreeMem(boot
, bsize
);
715 /* Write back-up boot sector and FS info sector */
717 if ((err
= AccessDisk(TRUE
, first_device_sector
+ 6, 1, bsize
,
718 (UBYTE
*)boot
)) != 0) {
719 D(bug("[fat] couldn't write back-up boot block (%ld)\n", err
));
720 FreeMem(boot
, bsize
);
725 memset(fsinfo
, 0, bsize
);
727 fsinfo
->lead_sig
= AROS_LONG2LE(FSI_LEAD_SIG
);
728 fsinfo
->struct_sig
= AROS_LONG2LE(FSI_STRUCT_SIG
);
729 fsinfo
->trail_sig
= AROS_LONG2LE(FSI_TRAIL_SIG
);
730 fsinfo
->free_count
= AROS_LONG2LE(0xFFFFFFFF);
731 fsinfo
->next_free
= AROS_LONG2LE(0xFFFFFFFF);
733 if ((err
= AccessDisk(TRUE
, first_device_sector
+ 1, 1, bsize
,
734 (UBYTE
*)fsinfo
)) != 0) {
735 D(bug("[fat] couldn't write back-up boot block (%ld)\n", err
));
736 FreeMem(boot
, bsize
);
741 FreeMem(boot
, bsize
);
743 glob
->formatting
= TRUE
;
748 LONG
SetVolumeName(struct FSSuper
*sb
, UBYTE
*name
, UWORD len
) {
753 struct DosEnvec
*dosenv
= BADDR(glob
->fssm
->fssm_Environ
);
754 ULONG bsize
= dosenv
->de_SizeBlock
* 4;
755 struct FATBootSector
*boot
;
757 /* read boot block */
758 boot
= AllocMem(bsize
, MEMF_ANY
);
760 return ERROR_NO_FREE_STORE
;
762 if ((err
= AccessDisk(FALSE
, sb
->first_device_sector
, 1, bsize
, (UBYTE
*)boot
)) != 0) {
763 D(bug("[fat] couldn't read boot block (%ld)\n", err
));
764 FreeMem(boot
, bsize
);
768 D(bug("[fat] searching root directory for volume name\n"));
770 /* search the directory for the volume id entry. it would've been nice to
771 * just use GetNextDirEntry but I didn't want a flag or something to tell
772 * it not to skip the volume name */
773 InitDirHandle(sb
, 0, &dh
, FALSE
);
775 while ((err
= GetDirEntry(&dh
, dh
.cur_index
+ 1, &de
)) == 0) {
777 /* match the volume id entry */
778 if ((de
.e
.entry
.attr
& ATTR_VOLUME_ID_MASK
) == ATTR_VOLUME_ID
779 && de
.e
.entry
.name
[0] != 0xe5) {
780 D(bug("[fat] found volume id entry %ld\n", dh
.cur_index
));
785 /* bail out if we hit the end of the dir */
786 if (de
.e
.entry
.name
[0] == 0x00) {
787 D(bug("[fat] found end-of-directory marker, volume name entry not found\n"));
788 err
= ERROR_OBJECT_NOT_FOUND
;
793 /* create a new volume id entry if there wasn't one */
795 err
= AllocDirEntry(&dh
, 0, &de
);
797 FillDirEntry(&de
, ATTR_VOLUME_ID
, 0);
800 /* copy the name in */
802 for (i
= 0; i
< 11; i
++)
804 de
.e
.entry
.name
[i
] = toupper(name
[i
]);
806 de
.e
.entry
.name
[i
] = ' ';
808 if ((err
= UpdateDirEntry(&de
)) != 0) {
809 D(bug("[fat] couldn't change volume name\n"));
814 /* copy name to boot block as well, and save */
816 CopyMem(de
.e
.entry
.name
, boot
->ebpbs
.ebpb32
.ebpb
.bs_vollab
, 11);
818 CopyMem(de
.e
.entry
.name
, boot
->ebpbs
.ebpb
.bs_vollab
, 11);
820 if ((err
= AccessDisk(TRUE
, sb
->first_device_sector
, 1, bsize
,
821 (UBYTE
*)boot
)) != 0)
822 D(bug("[fat] couldn't write boot block (%ld)\n", err
));
823 FreeMem(boot
, bsize
);
825 /* update name in sb */
826 sb
->volume
.name
[0] = len
<= 11 ? len
: 11;
827 CopyMem(name
, &(sb
->volume
.name
[1]), sb
->volume
.name
[0]);
828 sb
->volume
.name
[sb
->volume
.name
[0]+1] = '\0';
830 D(bug("[fat] new volume name is '%s'\n", &(sb
->volume
.name
[1])));
832 ReleaseDirHandle(&dh
);
836 LONG
FindFreeCluster(struct FSSuper
*sb
, ULONG
*rcluster
) {
840 for (cluster
= sb
->next_cluster
;
841 cluster
< 2 + sb
->clusters_count
&& !found
;
844 if (GET_NEXT_CLUSTER(sb
, cluster
) == 0)
853 for (cluster
= 2; cluster
< sb
->next_cluster
&& !found
;
856 if (GET_NEXT_CLUSTER(sb
, cluster
) == 0)
865 D(bug("[fat] no more free clusters, we're out of space\n"));
866 return ERROR_DISK_FULL
;
869 sb
->next_cluster
= *rcluster
;
871 D(bug("[fat] found free cluster %ld\n", *rcluster
));
876 void FreeFATSuper(struct FSSuper
*sb
) {
877 D(bug("\tRemoving Super Block from memory\n"));
878 Cache_DestroyCache(sb
->cache
);
879 FreeVecPooled(glob
->mempool
, sb
->fat_buffers
);
880 sb
->fat_buffers
= NULL
;
881 FreeVecPooled(glob
->mempool
, sb
->fat_blocks
);
882 sb
->fat_blocks
= NULL
;
885 /* see how many unused clusters are available */
886 void CountFreeClusters(struct FSSuper
*sb
) {
890 /* loop over all the data clusters */
891 for (cluster
= 2; cluster
< sb
->clusters_count
+ 2; cluster
++)
893 /* record the free ones */
894 if (GET_NEXT_CLUSTER(sb
, cluster
) == 0)
898 /* put the value away for later */
899 sb
->free_clusters
= free
;
901 D(bug("\tfree clusters: %ld\n", free
));
904 void AllocCluster(struct FSSuper
*sb
, ULONG cluster
) {
905 SET_NEXT_CLUSTER(sb
, cluster
, sb
->eoc_mark
);
907 if (sb
->fsinfo_buffer
!= NULL
) {
908 sb
->fsinfo_buffer
->free_count
= AROS_LONG2LE(sb
->free_clusters
);
909 sb
->fsinfo_buffer
->next_free
= AROS_LONG2LE(sb
->next_cluster
);
910 Cache_MarkBlockDirty(sb
->cache
, sb
->fsinfo_block
);
914 void FreeCluster(struct FSSuper
*sb
, ULONG cluster
) {
915 SET_NEXT_CLUSTER(sb
, cluster
, 0);
917 if (sb
->fsinfo_buffer
!= NULL
) {
918 sb
->fsinfo_buffer
->free_count
= AROS_LONG2LE(sb
->free_clusters
);
919 Cache_MarkBlockDirty(sb
->cache
, sb
->fsinfo_block
);
923 void ConvertFATDate(UWORD date
, UWORD time
, struct DateStamp
*ds
) {
924 ULONG year
, month
, day
, hours
, mins
, secs
;
925 struct ClockData clock_data
;
927 /* date bits: yyyy yyym mmmd dddd */
928 year
= (date
& 0xfe00) >> 9; /* bits 15-9 */
929 month
= (date
& 0x01e0) >> 5; /* bits 8-5 */
930 day
= date
& 0x001f; /* bits 4-0 */
932 /* time bits: hhhh hmmm mmms ssss */
933 hours
= (time
& 0xf800) >> 11; /* bits 15-11 */
934 mins
= (time
& 0x07e0) >> 5; /* bits 10-5 */
935 secs
= time
& 0x001f; /* bits 4-0 */
937 D(bug("[fat] converting fat date: year %d month %d day %d hours %d mins %d secs %d\n", year
, month
, day
, hours
, mins
, secs
));
939 clock_data
.year
= 1980 + year
;
940 clock_data
.month
= month
;
941 clock_data
.mday
= day
;
942 clock_data
.hour
= hours
;
943 clock_data
.min
= mins
;
944 clock_data
.sec
= secs
<< 1;
945 secs
= Date2Amiga(&clock_data
);
947 /* calculate days since 1978-01-01 (DOS epoch) */
948 ds
->ds_Days
= secs
/ (60 * 60 * 24);
950 /* minutes since midnight */
951 ds
->ds_Minute
= secs
/ 60 % (24 * 60);
953 /* 1/50 sec ticks since last minute */
954 ds
->ds_Tick
= secs
% 60 * TICKS_PER_SECOND
;
956 D(bug("[fat] converted fat date: days %ld minutes %ld ticks %ld\n", ds
->ds_Days
, ds
->ds_Minute
, ds
->ds_Tick
));
959 void ConvertAROSDate(struct DateStamp
*ds
, UWORD
*date
, UWORD
*time
) {
960 ULONG year
, month
, day
, hours
, mins
, secs
;
961 struct ClockData clock_data
;
963 /* convert datestamp to seconds since 1978 */
964 secs
= ds
->ds_Days
* 60 * 60 * 24 + ds
->ds_Minute
* 60
965 + ds
->ds_Tick
/ TICKS_PER_SECOND
;
967 /* Round up to next even second because of FAT's two-second granularity */
968 secs
= (secs
& ~1) + 2;
970 /* convert seconds since 1978 to calendar/time data */
971 Amiga2Date(secs
, &clock_data
);
973 /* get values used in FAT dates */
974 year
= clock_data
.year
- 1980;
975 month
= clock_data
.month
- 0;
976 day
= clock_data
.mday
;
977 hours
= clock_data
.hour
;
978 mins
= clock_data
.min
;
979 secs
= clock_data
.sec
>> 1;
981 /* all that remains is to bit-encode the whole lot */
983 /* date bits: yyyy yyym mmmd dddd */
984 *date
= (((ULONG
) year
) << 9) | (((ULONG
) month
) << 5) | day
;
986 /* time bits: hhhh hmmm mmms ssss */
987 *time
= (((ULONG
) hours
) << 11) | (((ULONG
) mins
) << 5) | secs
;