[PATCH v3 1/5] xfs: use b_maps[] for discontiguous buffers

[Christoph Hellwig]

On Tue, Dec 04, 2012 at 05:18:02PM -0600, Mark Tinguely wrote:
> Commits starting at 77c1a08 introduced a multiple segment support
> to xfs_buf. xfs_trans_buf_item_match() could not find a multi-segment
> buffer in the transaction because it was looking at the single segment
> block number rather than the multi-segment b_maps[0].bm.bn. This
> results on a recursive buffer lock that can never be satisfied.
> 
> This patch:
>  1) Changed the remaining b_map accesses to be b_maps[0] accesses.
>  2) Renames the single segment b_map structure to __b_map to avoid
>     future confusion.
> 
> Signed-off-by: Mark Tinguely <tinguely at sgi.com>
> Reviewed-by: Dave Chinner <dchinner at redhat.com>

Looks good,

Reviewed-by: Christoph Hellwig <hch at lst.de>