[libvirt] [PATCH] Fix raw storage volume creation for allocation < capacity.

[Cole Robinson <crobinso redhat com>]

CreateXMLFrom changes accidentally caused all raw volume creation to be
fully allocated (as though allocation == capacity). Fix this.

Also force CreateXMLFrom to maintain the previous behavior: sparseness
should still be maintained since we search for holes when copying, and the
clone behavior hasn't been tested with anything but the broken behavior.

Signed-off-by: Cole Robinson <crobinso redhat com>
---
 src/storage_backend_fs.c |    2 +-
 src/storage_driver.c     |    5 +++++
 2 files changed, 6 insertions(+), 1 deletions(-)

diff --git a/src/storage_backend_fs.c b/src/storage_backend_fs.c
index 0e93e54..c3d66b5 100644
--- a/src/storage_backend_fs.c
+++ b/src/storage_backend_fs.c
@@ -1047,7 +1047,7 @@ static int createRaw(virConnectPtr conn,
         goto cleanup;
     }
 
-    remain = vol->capacity;
+    remain = vol->allocation;
 
     if (inputfd != -1) {
         int amtread = -1;
diff --git a/src/storage_driver.c b/src/storage_driver.c
index 71e64a4..57a93c1 100644
--- a/src/storage_driver.c
+++ b/src/storage_driver.c
@@ -1377,6 +1377,11 @@ storageVolumeCreateXMLFrom(virStoragePoolPtr obj,
     if (newvol->capacity < origvol->capacity)
         newvol->capacity = origvol->capacity;
 
+    /* Make sure allocation is at least as large as the destination cap,
+     * to make absolutely sure we copy all possible contents */
+    if (newvol->allocation < origvol->capacity;
+        newvol->allocation = origvol->capacity;
+
     if (!backend->buildVolFrom) {
         virStorageReportError(obj->conn, VIR_ERR_NO_SUPPORT,
                               "%s", _("storage pool does not support volume creation from an existing volume"));
-- 
1.6.0.6