From: Zheng Liu Date: Mon, 18 Feb 2013 05:29:59 +0000 (-0500) Subject: ext4: lookup block mapping in extent status tree X-Git-Tag: v3.9-rc1~64^2~6 X-Git-Url: http://git.openpandora.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=d100eef2440fea13e4f09e88b1c8bcbca64beb9f;p=pandora-kernel.git ext4: lookup block mapping in extent status tree After tracking all extent status, we already have a extent cache in memory. Every time we want to lookup a block mapping, we can first try to lookup it in extent status tree to avoid a potential disk I/O. A new function called ext4_es_lookup_extent is defined to finish this work. When we try to lookup a block mapping, we always call ext4_map_blocks and/or ext4_da_map_blocks. So in these functions we first try to lookup a block mapping in extent status tree. A new flag EXT4_GET_BLOCKS_NO_PUT_HOLE is used in ext4_da_map_blocks in order not to put a hole into extent status tree because this hole will be converted to delayed extent in the tree immediately. Signed-off-by: Zheng Liu Signed-off-by: "Theodore Ts'o" Cc: Jan kara --- Reading git-diff-tree failed