From 037689d8969c493d39153fd920ad81e161b0d55c Mon Sep 17 00:00:00 2001 From: Kevin Wolf Date: Tue, 26 Mar 2013 17:49:59 +0100 Subject: [PATCH] qcow2: Decouple cluster allocation from cluster reuse code This moves some code that prepares the allocation of new clusters to where the actual allocation happens. This is the minimum required to be able to move it to a separate function in the next patch. Signed-off-by: Kevin Wolf Signed-off-by: Stefan Hajnoczi --- block/qcow2-cluster.c | 35 ++++++++++++++++++++--------------- 1 file changed, 20 insertions(+), 15 deletions(-) diff --git a/block/qcow2-cluster.c b/block/qcow2-cluster.c index 202adb480..9550927c4 100644 --- a/block/qcow2-cluster.c +++ b/block/qcow2-cluster.c @@ -946,10 +946,7 @@ again: cluster_offset = be64_to_cpu(l2_table[l2_index]); - /* - * Check how many clusters are already allocated and don't need COW, and how - * many need a new allocation. - */ + /* Check how many clusters are already allocated and don't need COW */ if (qcow2_get_cluster_type(cluster_offset) == QCOW2_CLUSTER_NORMAL && (cluster_offset & QCOW_OFLAG_COPIED)) { @@ -965,17 +962,6 @@ again: cluster_offset = 0; } - if (nb_clusters > 0) { - /* For the moment, overwrite compressed clusters one by one */ - uint64_t entry = be64_to_cpu(l2_table[l2_index + keep_clusters]); - if (entry & QCOW_OFLAG_COMPRESSED) { - nb_clusters = 1; - } else { - nb_clusters = count_cow_clusters(s, nb_clusters, l2_table, - l2_index + keep_clusters); - } - } - cluster_offset &= L2E_OFFSET_MASK; /* @@ -996,6 +982,25 @@ again: uint64_t alloc_cluster_offset; uint64_t keep_bytes = keep_clusters * s->cluster_size; + ret = get_cluster_table(bs, offset, &l2_table, &l2_index); + if (ret < 0) { + return ret; + } + + /* For the moment, overwrite compressed clusters one by one */ + uint64_t entry = be64_to_cpu(l2_table[l2_index + keep_clusters]); + if (entry & QCOW_OFLAG_COMPRESSED) { + nb_clusters = 1; + } else { + nb_clusters = count_cow_clusters(s, nb_clusters, l2_table, + l2_index + keep_clusters); + } + + ret = qcow2_cache_put(bs, s->l2_table_cache, (void**) &l2_table); + if (ret < 0) { + return ret; + } + /* Calculate start and size of allocation */ alloc_offset = offset + keep_bytes; -- 2.39.2