[dm-devel] scsi: unify the error handling of the prep functions

[Mike Snitzer]

On Mon, Jul 05 2010 at 12:00am -0400,
FUJITA Tomonori <fujita.tomonori at lab.ntt.co.jp> wrote:

> This can be applied to the block's for-2.6.36.
> 
> =
> From: FUJITA Tomonori <fujita.tomonori at lab.ntt.co.jp>
> Subject: [PATCH] scsi: unify the error handling of the prep functions
> 
> This unifies the error handling of the prep functions (and fix the
> leak of a page allocated for discard in the case of BLKPREP_KILL or
> BLK_PREP_DEFER).
> 
> The error handling of the prep path is very messy. Some errors are
> handled in the prep functions while some are in scsi_prep_return().
> 
> Let's handle all the errors in scsi_prep_return().
> 
> Signed-off-by: FUJITA Tomonori <fujita.tomonori at lab.ntt.co.jp>

This patch addresses the discard page leak too (scsi_prep_error calls
scsi_unprep_request which calls blk_unprep_request).

Acked-by: Mike Snitzer <snitzer at redhat.com>