From: Mikulas Patocka Date: Thu, 10 Dec 2009 23:52:31 +0000 (+0000) Subject: dm snapshot: avoid allocating exceptions in merge X-Git-Tag: v2.6.33-rc1~75^2~9 X-Git-Url: http://git.openpandora.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=3452c2a1eb5b93c1b9fb0d22bd5b07c0cee4dc29;p=pandora-kernel.git dm snapshot: avoid allocating exceptions in merge The snapshot-merge target should not allocate new exceptions because the intent is to merge all of its exceptions as quickly and safely as possible. This patch introduces the snapshot-merge mapping function and updates __origin_write() so that it doesn't allocate exceptions on any snapshots that are being merged. If a write request to a merging snapshot device is to be dispatched directly to the origin (because the chunk is not remapped or was already merged), snapshot_merge_map() must make exceptions in other snapshots so calls do_origin(). Signed-off-by: Mikulas Patocka Signed-off-by: Mike Snitzer Signed-off-by: Alasdair G Kergon --- Reading git-diff-tree failed