ide-cd: document capacity hack

Just copy the comment from drivers/scsi/sr.c::sr_done()
(from which the capacity hack has been originated).

Cc: Borislav Petkov <petkovbb@gmail.com>
Acked-by: Sergei Shtylyov <sshtylyov@ru.mvista.com>
Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>
This commit is contained in:
Bartlomiej Zolnierkiewicz 2009-02-25 20:28:23 +01:00
parent f38344b0a0
commit d3dd7107f4

View file

@ -194,6 +194,14 @@ static void cdrom_analyze_sense_data(ide_drive_t *drive,
bio_sectors = max(bio_sectors(failed_command->bio), 4U);
sector &= ~(bio_sectors - 1);
/*
* The SCSI specification allows for the value
* returned by READ CAPACITY to be up to 75 2K
* sectors past the last readable block.
* Therefore, if we hit a medium error within the
* last 75 2K sectors, we decrease the saved size
* value.
*/
if (sector < get_capacity(info->disk) &&
drive->probed_capacity - sector < 4 * 75)
set_capacity(info->disk, sector);