On Wed, Feb 13, 2013 at 1:22 PM, Kevin Wolf <kw...@redhat.com> wrote: > Look only for clusters that start at a given physical offset. > > Signed-off-by: Kevin Wolf <kw...@redhat.com> > --- > block/qcow2-cluster.c | 26 ++++++++++++++++++-------- > 1 files changed, 18 insertions(+), 8 deletions(-) > > diff --git a/block/qcow2-cluster.c b/block/qcow2-cluster.c > index 5ce2c88..90fe36c 100644 > --- a/block/qcow2-cluster.c > +++ b/block/qcow2-cluster.c > @@ -827,8 +827,6 @@ 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) > @@ -843,7 +841,6 @@ 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 > @@ -867,6 +864,15 @@ 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 */ > + if (*host_offset != 0 > + && (cluster_offset & L2E_OFFSET_MASK) != *host_offset) > + {
Braces should cuddle with the previous line. > + *bytes = 0; > + ret = 0; > + goto out; > + } > + > /* We keep all QCOW_OFLAG_COPIED clusters */ > keep_clusters = > count_contiguous_clusters(nb_clusters, s->cluster_size, > @@ -880,19 +886,22 @@ 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; > } > > @@ -1162,7 +1171,6 @@ again: > > /* > * 2. Count contiguous COPIED clusters. > - * TODO: Consider cluster_offset if set in step 1c. > */ > ret = handle_copied(bs, offset, &cluster_offset, &cur_bytes, m); > if (ret < 0) { > @@ -1175,6 +1183,8 @@ again: > if (!*host_offset) { > *host_offset = cluster_offset; > } > + } else if (cur_bytes == 0) { > + goto done; > } else { > keep_clusters = 0; > } > -- > 1.7.6.5 > >