Btrfs: map the node block when looking for readahead targets
authorJosef Bacik <josef@redhat.com>
Wed, 11 May 2011 16:17:34 +0000 (12:17 -0400)
committerJosef Bacik <josef@redhat.com>
Mon, 23 May 2011 17:03:10 +0000 (13:03 -0400)
commitcb25c2ea6a79702ab7895b873c6c43e0d3bc3c72
tree08d112b38a1e017b563035b78861288dbf0d2fd6
parentaf60bed24eb0e3b6d93eaa6bb395a5721e6c09a8
Btrfs: map the node block when looking for readahead targets

If we have particularly full nodes, we could call btrfs_node_blockptr up to 32
times, which is 32 pairs of kmap/kunmap, which _sucks_.  So go ahead and map the
extent buffer while we look for readahead targets.  Thanks,

Signed-off-by: Josef Bacik <josef@redhat.com>
fs/btrfs/ctree.c