From: Marcelo Tosatti <marcelo.tosatti@cyclades.com>
From: Alain Knaff <alain.knaff@lll.lu>
This patch adds support for floppy disks whose sectors are numbered
starting at 0 rather than 1 as usual disks would be. This format is used
for some CP/M disks, and also for certain music samplers (such as Ensoniq
Ensoniq EPS 16plus).
In order to use it, you need an fdutils with the current patch from
http://fdutils.linux.lu as well, and then do setfdrpm /dev/fd0 dd zerobased
sect=10 or setfdprm /dev/fd0 hd zerobased sect.
In addtion, the patch also fixes my email addresses. I no longer use
pobox.com.
---
25-akpm/drivers/block/floppy.c | 19 +++++++++++++++----
25-akpm/include/linux/fd.h | 1 +
2 files changed, 16 insertions(+), 4 deletions(-)
diff -puN drivers/block/floppy.c~support-zerobased-floppies drivers/block/floppy.c
--- 25/drivers/block/floppy.c~support-zerobased-floppies Mon Mar 29 15:53:38 2004
+++ 25-akpm/drivers/block/floppy.c Mon Mar 29 15:53:38 2004
@@ -2258,6 +2258,10 @@ static void setup_format_params(int trac
}
}
}
+ if(_floppy->stretch & FD_ZEROBASED) {
+ for(count = 0; count < F_SECT_PER_TRACK; count++)
+ here[count].sect--;
+ }
}
static void redo_format(void)
@@ -2679,7 +2683,8 @@ static int make_raw_rw_request(void)
}
HEAD = fsector_t / _floppy->sect;
- if (((_floppy->stretch & FD_SWAPSIDES) || TESTF(FD_NEED_TWADDLE)) &&
+ if (((_floppy->stretch & (FD_SWAPSIDES | FD_ZEROBASED)) ||
+ TESTF(FD_NEED_TWADDLE)) &&
fsector_t < _floppy->sect)
max_sector = _floppy->sect;
@@ -2709,7 +2714,8 @@ static int make_raw_rw_request(void)
GAP = _floppy->gap;
CODE2SIZE;
SECT_PER_TRACK = _floppy->sect << 2 >> SIZECODE;
- SECTOR = ((fsector_t % _floppy->sect) << 2 >> SIZECODE) + 1;
+ SECTOR = ((fsector_t % _floppy->sect) << 2 >> SIZECODE) +
+ ((_floppy->stretch & FD_ZEROBASED) ? 0 : 1);
/* tracksize describes the size which can be filled up with sectors
* of size ssize.
@@ -3346,7 +3352,7 @@ static inline int set_geometry(unsigned
g->track <= 0 ||
g->track > UDP->tracks>>STRETCH(g) ||
/* check if reserved bits are set */
- (g->stretch&~(FD_STRETCH|FD_SWAPSIDES)) != 0)
+ (g->stretch&~(FD_STRETCH|FD_SWAPSIDES|FD_ZEROBASED)) != 0)
return -EINVAL;
if (type){
if (!capable(CAP_SYS_ADMIN))
@@ -3367,11 +3373,13 @@ static inline int set_geometry(unsigned
}
up(&open_lock);
} else {
+ int oldStretch;
LOCK_FDC(drive,1);
if (cmd != FDDEFPRM)
/* notice a disk change immediately, else
* we lose our settings immediately*/
CALL(poll_drive(1, FD_RAW_NEED_DISK));
+ oldStretch = g->stretch;
user_params[drive] = *g;
if (buffer_drive == drive)
SUPBOUND(buffer_max, user_params[drive].sect);
@@ -3386,7 +3394,10 @@ static inline int set_geometry(unsigned
* whose number will change. This is useful, because
* mtools often changes the geometry of the disk after
* looking at the boot block */
- if (DRS->maxblock > user_params[drive].sect || DRS->maxtrack)
+ if (DRS->maxblock > user_params[drive].sect ||
+ DRS->maxtrack ||
+ ((user_params[drive].sect ^ oldStretch) &
+ (FD_SWAPSIDES | FD_ZEROBASED)))
invalidate_drive(bdev);
else
process_fd_request();
diff -puN include/linux/fd.h~support-zerobased-floppies include/linux/fd.h
--- 25/include/linux/fd.h~support-zerobased-floppies Mon Mar 29 15:53:38 2004
+++ 25-akpm/include/linux/fd.h Mon Mar 29 15:53:38 2004
@@ -17,6 +17,7 @@ struct floppy_struct {
stretch; /* !=0 means double track steps */
#define FD_STRETCH 1
#define FD_SWAPSIDES 2
+#define FD_ZEROBASED 4
unsigned char gap, /* gap1 size */
_