diff options
| -rw-r--r-- | hw/block/fdc.c | 72 |
1 files changed, 52 insertions, 20 deletions
diff --git a/hw/block/fdc.c b/hw/block/fdc.c index e51154b5b7..6e0c5fca55 100644 --- a/hw/block/fdc.c +++ b/hw/block/fdc.c @@ -125,7 +125,6 @@ static const FDFormat fd_formats[] = { { FLOPPY_DRIVE_TYPE_NONE, -1, -1, 0, 0, }, }; -__attribute__((__unused__)) static FDriveSize drive_size(FloppyDriveType drive) { switch (drive) { @@ -284,45 +283,78 @@ static int pick_geometry(FDrive *drv) BlockBackend *blk = drv->blk; const FDFormat *parse; uint64_t nb_sectors, size; - int i, first_match, match; + int i; + int match, size_match, type_match; + bool magic = drv->drive == FLOPPY_DRIVE_TYPE_AUTO; /* We can only pick a geometry if we have a diskette. */ if (!drv->media_inserted || drv->drive == FLOPPY_DRIVE_TYPE_NONE) { return -1; } + /* We need to determine the likely geometry of the inserted medium. + * In order of preference, we look for: + * (1) The same drive type and number of sectors, + * (2) The same diskette size and number of sectors, + * (3) The same drive type. + * + * In all cases, matches that occur higher in the drive table will take + * precedence over matches that occur later in the table. + */ blk_get_geometry(blk, &nb_sectors); - match = -1; - first_match = -1; + match = size_match = type_match = -1; for (i = 0; ; i++) { parse = &fd_formats[i]; if (parse->drive == FLOPPY_DRIVE_TYPE_NONE) { break; } - if (drv->drive == parse->drive || - drv->drive == FLOPPY_DRIVE_TYPE_AUTO) { - size = (parse->max_head + 1) * parse->max_track * - parse->last_sect; - if (nb_sectors == size) { - match = i; - break; + size = (parse->max_head + 1) * parse->max_track * parse->last_sect; + if (nb_sectors == size) { + if (magic || parse->drive == drv->drive) { + /* (1) perfect match -- nb_sectors and drive type */ + goto out; + } else if (drive_size(parse->drive) == drive_size(drv->drive)) { + /* (2) size match -- nb_sectors and physical medium size */ + match = (match == -1) ? i : match; + } else { + /* This is suspicious -- Did the user misconfigure? */ + size_match = (size_match == -1) ? i : size_match; } - if (first_match == -1) { - first_match = i; + } else if (type_match == -1) { + if ((parse->drive == drv->drive) || + (magic && (parse->drive == get_fallback_drive_type(drv)))) { + /* (3) type match -- nb_sectors mismatch, but matches the type + * specified explicitly by the user, or matches the fallback + * default type when using the drive autodetect mechanism */ + type_match = i; } } } + + /* No exact match found */ if (match == -1) { - if (first_match == -1) { - error_setg(&error_abort, "No candidate geometries present in table " - " for floppy drive type '%s'", - FloppyDriveType_lookup[drv->drive]); - } else { - match = first_match; + if (size_match != -1) { + parse = &fd_formats[size_match]; + FLOPPY_DPRINTF("User requested floppy drive type '%s', " + "but inserted medium appears to be a " + "%d sector '%s' type\n", + FloppyDriveType_lookup[drv->drive], + nb_sectors, + FloppyDriveType_lookup[parse->drive]); } - parse = &fd_formats[match]; + match = type_match; } + /* No match of any kind found -- fd_format is misconfigured, abort. */ + if (match == -1) { + error_setg(&error_abort, "No candidate geometries present in table " + " for floppy drive type '%s'", + FloppyDriveType_lookup[drv->drive]); + } + + parse = &(fd_formats[match]); + + out: if (parse->max_head == 0) { drv->flags &= ~FDISK_DBL_SIDES; } else { |