Re: [PATCH 2.6.24-rc1 1/2] sata_promise: ASIC PRD table bug workaround, take 2

[Jeff Garzik <jeff@garzik.org>]

Mikael Pettersson wrote:
> Second-generation Promise SATA controllers have an ASIC bug
> which can trigger if the last PRD entry is larger than 164 bytes,
> resulting in intermittent errors and possible data corruption.
> 
> Work around this by replacing calls to ata_qc_prep() with a
> private version that fills the PRD, checks the size of the
> last entry, and if necessary splits it to avoid the bug.
> Also reduce sg_tablesize by 1 to accommodate the new entry.
> 
> Tested on the second-generation SATA300 TX4 and SATA300 TX2plus,
> and the first-generation PDC20378.
> 
> Thanks to Alexander Sabourenkov for verifying the bug by
> studying the vendor driver, and for writing the initial patch
> upon which this one is based.
> 
> Signed-off-by: Mikael Pettersson <mikpe@it.uu.se>
> --
> Changes since previous version:
> * use new PDC_MAX_PRD constant to initialise sg_tablesize
> 
>  drivers/ata/sata_promise.c |   87 ++++++++++++++++++++++++++++++++++++++++++---
>  1 files changed, 83 insertions(+), 4 deletions(-)

applies 1-2 to #upstream-fixes