diff options
| -rw-r--r-- | block/qcow2-cluster.c | 28 |
1 files changed, 20 insertions, 8 deletions
diff --git a/block/qcow2-cluster.c b/block/qcow2-cluster.c index 5e5465dcac..239a997027 100644 --- a/block/qcow2-cluster.c +++ b/block/qcow2-cluster.c @@ -830,8 +830,6 @@ static int handle_dependencies(BlockDriverState *bs, uint64_t guest_offset, * the length of the area that can be written to. * * -errno: in error cases - * - * TODO Make non-zero host_offset behave like describe above */ static int handle_copied(BlockDriverState *bs, uint64_t guest_offset, uint64_t *host_offset, uint64_t *bytes, QCowL2Meta **m) @@ -846,7 +844,6 @@ static int handle_copied(BlockDriverState *bs, uint64_t guest_offset, trace_qcow2_handle_copied(qemu_coroutine_self(), guest_offset, *host_offset, *bytes); - assert(*host_offset == 0); /* * Calculate the number of clusters to look for. We stop at L2 table @@ -870,6 +867,16 @@ static int handle_copied(BlockDriverState *bs, uint64_t guest_offset, if (qcow2_get_cluster_type(cluster_offset) == QCOW2_CLUSTER_NORMAL && (cluster_offset & QCOW_OFLAG_COPIED)) { + /* If a specific host_offset is required, check it */ + bool offset_matches = + (cluster_offset & L2E_OFFSET_MASK) == *host_offset; + + if (*host_offset != 0 && !offset_matches) { + *bytes = 0; + ret = 0; + goto out; + } + /* We keep all QCOW_OFLAG_COPIED clusters */ keep_clusters = count_contiguous_clusters(nb_clusters, s->cluster_size, @@ -883,19 +890,22 @@ static int handle_copied(BlockDriverState *bs, uint64_t guest_offset, ret = 1; } else { - cluster_offset = 0; ret = 0; } - cluster_offset &= L2E_OFFSET_MASK; - *host_offset = cluster_offset; - /* Cleanup */ +out: pret = qcow2_cache_put(bs, s->l2_table_cache, (void**) &l2_table); if (pret < 0) { return pret; } + /* Only return a host offset if we actually made progress. Otherwise we + * would make requirements for handle_alloc() that it can't fulfill */ + if (ret) { + *host_offset = cluster_offset & L2E_OFFSET_MASK; + } + return ret; } @@ -1165,7 +1175,6 @@ again: /* * 2. Count contiguous COPIED clusters. - * TODO: Consider cluster_offset if set in step 1c. */ uint64_t tmp_bytes = cur_bytes; ret = handle_copied(bs, offset, &cluster_offset, &tmp_bytes, m); @@ -1179,6 +1188,9 @@ again: if (!*host_offset) { *host_offset = cluster_offset; } + } else if (cur_bytes == 0) { + keep_clusters = 0; + goto done; } else { keep_clusters = 0; } |