diff options
| -rw-r--r-- | drivers/block/floppy.c | 23 | ||||
| -rw-r--r-- | include/linux/fd.h | 8 |
2 files changed, 22 insertions, 9 deletions
diff --git a/drivers/block/floppy.c b/drivers/block/floppy.c index 9c0b494f5e8..cf64ddf5d83 100644 --- a/drivers/block/floppy.c +++ b/drivers/block/floppy.c @@ -423,8 +423,15 @@ static struct floppy_raw_cmd *raw_cmd, default_raw_cmd; * 1581's logical side 0 is on physical side 1, whereas the Sharp's logical * side 0 is on physical side 0 (but with the misnamed sector IDs). * 'stretch' should probably be renamed to something more general, like - * 'options'. Other parameters should be self-explanatory (see also - * setfdprm(8)). + * 'options'. + * + * Bits 2 through 9 of 'stretch' tell the number of the first sector. + * The LSB (bit 2) is flipped. For most disks, the first sector + * is 1 (represented by 0x00<<2). For some CP/M and music sampler + * disks (such as Ensoniq EPS 16plus) it is 0 (represented as 0x01<<2). + * For Amstrad CPC disks it is 0xC1 (represented as 0xC0<<2). + * + * Other parameters should be self-explanatory (see also setfdprm(8)). */ /* Size @@ -2236,9 +2243,9 @@ static void setup_format_params(int track) } } } - if (_floppy->stretch & FD_ZEROBASED) { + if (_floppy->stretch & FD_SECTBASEMASK) { for (count = 0; count < F_SECT_PER_TRACK; count++) - here[count].sect--; + here[count].sect += FD_SECTBASE(_floppy) - 1; } } @@ -2649,7 +2656,7 @@ static int make_raw_rw_request(void) } HEAD = fsector_t / _floppy->sect; - if (((_floppy->stretch & (FD_SWAPSIDES | FD_ZEROBASED)) || + if (((_floppy->stretch & (FD_SWAPSIDES | FD_SECTBASEMASK)) || TESTF(FD_NEED_TWADDLE)) && fsector_t < _floppy->sect) max_sector = _floppy->sect; @@ -2679,7 +2686,7 @@ static int make_raw_rw_request(void) CODE2SIZE; SECT_PER_TRACK = _floppy->sect << 2 >> SIZECODE; SECTOR = ((fsector_t % _floppy->sect) << 2 >> SIZECODE) + - ((_floppy->stretch & FD_ZEROBASED) ? 0 : 1); + FD_SECTBASE(_floppy); /* tracksize describes the size which can be filled up with sectors * of size ssize. @@ -3311,7 +3318,7 @@ static inline int set_geometry(unsigned int cmd, struct floppy_struct *g, g->head <= 0 || g->track <= 0 || g->track > UDP->tracks >> STRETCH(g) || /* check if reserved bits are set */ - (g->stretch & ~(FD_STRETCH | FD_SWAPSIDES | FD_ZEROBASED)) != 0) + (g->stretch & ~(FD_STRETCH | FD_SWAPSIDES | FD_SECTBASEMASK)) != 0) return -EINVAL; if (type) { if (!capable(CAP_SYS_ADMIN)) @@ -3356,7 +3363,7 @@ static inline int set_geometry(unsigned int cmd, struct floppy_struct *g, if (DRS->maxblock > user_params[drive].sect || DRS->maxtrack || ((user_params[drive].sect ^ oldStretch) & - (FD_SWAPSIDES | FD_ZEROBASED))) + (FD_SWAPSIDES | FD_SECTBASEMASK))) invalidate_drive(bdev); else process_fd_request(); diff --git a/include/linux/fd.h b/include/linux/fd.h index b6bd41d2b46..f5d194af07a 100644 --- a/include/linux/fd.h +++ b/include/linux/fd.h @@ -15,10 +15,16 @@ struct floppy_struct { sect, /* sectors per track */ head, /* nr of heads */ track, /* nr of tracks */ - stretch; /* !=0 means double track steps */ + stretch; /* bit 0 !=0 means double track steps */ + /* bit 1 != 0 means swap sides */ + /* bits 2..9 give the first sector */ + /* number (the LSB is flipped) */ #define FD_STRETCH 1 #define FD_SWAPSIDES 2 #define FD_ZEROBASED 4 +#define FD_SECTBASEMASK 0x3FC +#define FD_MKSECTBASE(s) (((s) ^ 1) << 2) +#define FD_SECTBASE(floppy) ((((floppy)->stretch & FD_SECTBASEMASK) >> 2) ^ 1) unsigned char gap, /* gap1 size */ |