Geert Uytterhoeven napisał(a):
On Mon, 25 Apr 2005, Stephen R Marenka wrote:On Mon, Apr 25, 2005 at 10:04:32PM +0200, Geert Uytterhoeven wrote:On Mon, 25 Apr 2005, Stephen R Marenka wrote:On Mon, Apr 25, 2005 at 09:54:26PM +0200, Petr Stehlik wrote:Stephen R Marenka p??e v Po 25. 04. 2005 v 14:46 -0500:What filesystem is native to atari? I'll add it for hd-media.msdos, with some very little differences that almost shouldn't matter.Does that mount as fat or vfat under linux?FAT, after applying http://linux-m68k-cvs.ubb.ca/~geert/linux-m68k-2.6.x-merging/POSTPONED/134-atari-fat.diff (which is probably in the Debian kernel anyway)Is something similar required for 2.4 also?While there is a similar patch for 2.4[*], I don't know if it's really required. Perhaps plain FAT works sufficiently well? Can someone of the Atari hackers please enlighten me?
In Atari world, original filesytem is known as TOSfs. TOSfs is similar to FAT, only some not important bits differ, so FAT routines are ok to deal with it.
Supported partition sizes differ, but with last TOS version it is 1GB (some OS functions support up to 2GB, but it is not offial), so 16bit FAT is used always.
On Atari, filesystem types on partition are marked with three ascii characters. Original Atari ones are 'GEM' and 'BGM'. 'GEM' is up to 32MB IIRC, 'BGM' is up to 1GB - so 16bit FAT can be always safely assumed.
Aditional, there are: 'LNX' - ext2 'SWP' - linux swap 'F32' - fat32 'MNX' - minix 'SV4' - Univ System 4 'RAW' - any (for compatibility reasons).There may be some kind of extended partitions, but I'm jey unsure of that (have to check the docs).
All fat partitions may be (but does not have to) vfat partitions.So, basically, all TOSfs ('GEM', 'BGM') can be assumed to be FAT16, optionally with vfat.
The http://linux-m68k-cvs.ubb.ca/~geert/linux-m68k-2.6.x-merging/POSTPONED/134-atari-fat.diff may be not needed (I've been reading Atari 'BGM' partitions on i386 without it), and
+ /* If more clusters than fat entries in 16-bit fat, we assume + * it's a real MSDOS partition with 12-bit fat. + */ + if (sbi->fat_bits != 32 && total_clusters+2 > sbi-> + fat_length*SECTOR_SIZE*8/sbi->fat_bits) + sbi->fat_bits = 12; part scares me ;) -- Semper Fidelis Adam Klobukowski atari@gabo.pl