Re: [PATCH] ide-cd: document capacity hack

[Sergei Shtylyov <sshtylyov@ru.mvista.com>]

Hello.

Bartlomiej Zolnierkiewicz wrote:

> 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>
> Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>

Acked-by: Sergei Shtylyov <sshtylyov@ru.mvista.com>

> Index: b/drivers/ide/ide-cd.c
> ===================================================================
> --- a/drivers/ide/ide-cd.c
> +++ b/drivers/ide/ide-cd.c
> @@ -189,6 +189,14 @@ static void cdrom_analyze_sense_data(ide
>  			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.

    Oh horror... :-)

> +			 * 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);

    Would be nice if the CHS capacity workround was finally documented too? ;-)

MBR, Sergei