Re: hdparm write cache settings

[Mark Lord <mlord@pobox.com>]

Hi,

Sure, I can update hdparm to first attempt HDIO_SET_WCACHE.
If that call is nak'd (usually due to lack of kernel support for it),
then hdparm will use HDIO_DRIVE_CMD as a fallback.

This is a VERY popular setting among end-users of Linux.

Cheers
-- 
Mark Lord
Real-Time Remedies Inc.
mlord@pobox.com

Doug Maxey wrote:
> Mark,
> 
> I have been tweaking the idedisk_setup() and write_cache() to handle
> drives with write cache disabled by default and the barrier settings on
> changes between WC enabled and disabled.
> 
> Bart has pointed out in offline mail, and testing has confirmed, that 
> HDIO_DRIVE_CMD is used, which bypasses the settings parameter lookup 
> in generic_ide_ioctl() of the drive settings enabled in ide_add_settings().  
> 
> Is it reasonable that a change could be made to enable the use of
> HDIO_SET_WCACHE in hdparm?
> 
> Or should I be looking to intercept the call and do The Right Thing
> (TM:) in the ide driver?
> 
> 
> ++doug
> 
> 
> 
> 
>