dossrv: Implement support for != 512 sector and track sizes

The iotrack buffer layer always assumed 512 byte sector
size and 9 sectors per track.

To support 4K sector size fats, make the iotrack code
deal with it.

Instead of the fixed size Track structure, we just allocate
the pointers and buffers dynamically, and move the sector
size and tack size in the Xfs structure.

Tracks can still be reused between differnet file-systems
after a purgetrack().

The initial fat header has to be read with devread()
instead of getsect() to determine the sector/track size
of the file-system.

1 files changed, 1 insertions, 20 deletions

diff --git a/sys/src/cmd/dossrv/iotrack.h b/sys/src/cmd/dossrv/iotrack.h
index 921a75c3f..098677ab2 100644
--- a/sys/src/cmd/dossrv/iotrack.h
+++ b/sys/src/cmd/dossrv/iotrack.h
@@ -1,7 +1,6 @@
 typedef struct MLock	MLock;
 typedef	struct Iosect	Iosect;
 typedef	struct Iotrack	Iotrack;
-typedef struct Track	Track;
 typedef struct Xfs	Xfs;
 
 struct MLock
@@ -29,41 +28,23 @@ struct Iotrack
 	Iotrack	*hprev;
 	MLock	lock;
 	int	ref;
-	Track	*tp;
-};
-
-enum{
-	Sectorsize = 512,
-	Sect2trk = 9,
-	Trksize = Sectorsize*Sect2trk
-};
-
-struct Track
-{
-	Iosect *p[Sect2trk];
-	uchar	buf[Sect2trk][Sectorsize];
+	Iosect	**tp;
 };
 
 #define	BMOD		(1<<0)
 #define	BIMM		(1<<1)
 #define	BSTALE		(1<<2)
 
-Iosect*	getiosect(Xfs*, vlong, int);
 Iosect*	getosect(Xfs*, vlong);
 Iosect*	getsect(Xfs*, vlong);
-Iosect*	newsect(void);
-Iotrack*	getiotrack(Xfs*, vlong);
 int	canmlock(MLock*);
-int	devcheck(Xfs*);
 int	devread(Xfs*, vlong, void*, long);
 int	devwrite(Xfs*, vlong, void*, long);
 int	tread(Iotrack*);
 int	twrite(Iotrack*);
-void	freesect(Iosect*);
 void	iotrack_init(void);
 void	mlock(MLock*);
 void	purgebuf(Xfs*);
-void	purgetrack(Iotrack*);
 void	putsect(Iosect*);
 void	sync(void);
 void	unmlock(MLock*);