Restore skipping of setting capacity

Commit id 'ac9a0963' refactored out the 'withCapacity' for the
virStorageBackendUpdateVolInfo() API.  See:

http://www.redhat.com/archives/libvir-list/2014-April/msg00043.html

This resulted in a difference in how 'virsh vol-info --pool <poolName>
<volume>' or 'virsh vol-list vol-list --pool <poolName> --details' outputs
the capacity information for a directory pool with a qcow2 sparse file.

For example, using the following XML

mkdir /home/TestPool
cat testpool.xml
<pool type='dir'>
  <name>TestPool</name>
  <uuid>6bf80895-10b6-75a6-6059-89fdea2aefb7</uuid>
  <source>
  </source>
  <target>
    <path>/home/TestPool</path>
    <permissions>
      <mode>0755</mode>
      <owner>0</owner>
      <group>0</group>
    </permissions>
  </target>
</pool>

virsh pool-create testpool.xml
virsh vol-create-as --pool TestPool temp_vol_1 \
      --capacity 1048576 --allocation 1048576 --format qcow2
virsh vol-info --pool TestPool temp_vol_1

Results in listing a Capacity value.  Prior to the commit, the value would
be '1.0 MiB' (1048576 bytes). However, after the commit the output would be
(for example) '192.50 KiB', which for my system was the size of the volume
in my file system (eg 'ls -l TestPool/temp_vol_1' results in '197120' bytes
or 192.50 KiB). While perhaps technically correct, it's not necessarily
what the user expected (certainly virt-test didn't expect it).

This patch restores the code to not update the target capacity for this path

src/storage/storage_backend.c

@@ -1403,6 +1403,7 @@ virStorageBackendVolOpen(const char *path, struct stat *sb,
 
 int
 virStorageBackendUpdateVolTargetInfo(virStorageSourcePtr target,
+                                     bool updateCapacity,
                                      bool withBlockVolFormat,
                                      unsigned int openflags)
 {
@@ -1413,7 +1414,8 @@ virStorageBackendUpdateVolTargetInfo(virStorageSourcePtr target,
         goto cleanup;
     fd = ret;
 
-    if ((ret = virStorageBackendUpdateVolTargetInfoFD(target, fd, &sb)) < 0)
+    if ((ret = virStorageBackendUpdateVolTargetInfoFD(target, fd, &sb,
+                                                      updateCapacity)) < 0)
         goto cleanup;
 
     if (withBlockVolFormat) {
@@ -1429,18 +1431,21 @@ virStorageBackendUpdateVolTargetInfo(virStorageSourcePtr target,
 
 int
 virStorageBackendUpdateVolInfo(virStorageVolDefPtr vol,
+                               bool updateCapacity,
                                bool withBlockVolFormat,
                                unsigned int openflags)
 {
     int ret;
 
     if ((ret = virStorageBackendUpdateVolTargetInfo(&vol->target,
+                                    updateCapacity,
                                     withBlockVolFormat,
                                     openflags)) < 0)
         return ret;
 
     if (vol->backingStore.path &&
         (ret = virStorageBackendUpdateVolTargetInfo(&vol->backingStore,
+                                            updateCapacity,
                                             withBlockVolFormat,
                                             VIR_STORAGE_VOL_OPEN_DEFAULT)) < 0)
         return ret;
@@ -1453,15 +1458,15 @@ virStorageBackendUpdateVolInfo(virStorageVolDefPtr vol,
  * @target: target definition ptr of volume to update
  * @fd: fd of storage volume to update, via virStorageBackendOpenVol*, or -1
  * @sb: details about file (must match @fd, if that is provided)
- * @allocation: If not NULL, updated allocation information will be stored
- * @capacity: If not NULL, updated capacity info will be stored
+ * @updateCapacity: If true, updated capacity info will be stored
  *
  * Returns 0 for success, -1 on a legitimate error condition.
  */
 int
 virStorageBackendUpdateVolTargetInfoFD(virStorageSourcePtr target,
                                        int fd,
-                                       struct stat *sb)
+                                       struct stat *sb,
+                                       bool updateCapacity)
 {
 #if WITH_SELINUX
     security_context_t filecon = NULL;
@@ -1477,10 +1482,12 @@ virStorageBackendUpdateVolTargetInfoFD(virStorageSourcePtr target,
         /* Regular files may be sparse, so logical size (capacity) is not same
          * as actual allocation above
          */
-        target->capacity = sb->st_size;
+        if (updateCapacity)
+            target->capacity = sb->st_size;
     } else if (S_ISDIR(sb->st_mode)) {
         target->allocation = 0;
-        target->capacity = 0;
+        if (updateCapacity)
+            target->capacity = 0;
     } else if (fd >= 0) {
         off_t end;
         /* XXX this is POSIX compliant, but doesn't work for CHAR files,
@@ -1496,7 +1503,8 @@ virStorageBackendUpdateVolTargetInfoFD(virStorageSourcePtr target,
             return -1;
         }
         target->allocation = end;
-        target->capacity = end;
+        if (updateCapacity)
+            target->capacity = end;
     }
 
     if (!target->perms && VIR_ALLOC(target->perms) < 0)

src/storage/storage_backend.h

@@ -137,14 +137,17 @@ int virStorageBackendVolOpen(const char *path, struct stat *sb,
     ATTRIBUTE_NONNULL(1) ATTRIBUTE_NONNULL(2);
 
 int virStorageBackendUpdateVolInfo(virStorageVolDefPtr vol,
+                                   bool updateCapacity,
                                    bool withBlockVolFormat,
                                    unsigned int openflags);
 int virStorageBackendUpdateVolTargetInfo(virStorageSourcePtr target,
+                                         bool updateCapacity,
                                          bool withBlockVolFormat,
                                          unsigned int openflags);
 int virStorageBackendUpdateVolTargetInfoFD(virStorageSourcePtr target,
                                            int fd,
-                                           struct stat *sb);
+                                           struct stat *sb,
+                                           bool updateCapacity);
 
 char *virStorageBackendStablePath(virStoragePoolObjPtr pool,
                                   const char *devpath,

src/storage/storage_backend_disk.c

@@ -111,7 +111,7 @@ virStorageBackendDiskMakeDataVol(virStoragePoolObjPtr pool,
     }
 
     /* Refresh allocation/capacity/perms */
-    if (virStorageBackendUpdateVolInfo(vol, false,
+    if (virStorageBackendUpdateVolInfo(vol, true, false,
                                        VIR_STORAGE_VOL_OPEN_DEFAULT) < 0)
         return -1;
 

src/storage/storage_backend_fs.c

@@ -84,7 +84,8 @@ virStorageBackendProbeTarget(virStorageSourcePtr target,
         goto error; /* Take care to propagate ret, it is not always -1 */
     fd = ret;
 
-    if ((ret = virStorageBackendUpdateVolTargetInfoFD(target, fd, &sb)) < 0) {
+    if ((ret = virStorageBackendUpdateVolTargetInfoFD(target, fd,
+                                                      &sb, true)) < 0) {
         goto error;
     }
 
@@ -914,7 +915,7 @@ virStorageBackendFileSystemRefresh(virConnectPtr conn ATTRIBUTE_UNUSED,
             vol->backingStore.format = backingStoreFormat;
 
             ignore_value(virStorageBackendUpdateVolTargetInfo(
-                                               &vol->backingStore, false,
+                                               &vol->backingStore, true, false,
                                                VIR_STORAGE_VOL_OPEN_DEFAULT));
             /* If this failed, the backing file is currently unavailable,
              * the capacity, allocation, owner, group and mode are unknown.
@@ -1192,8 +1193,10 @@ virStorageBackendFileSystemVolRefresh(virConnectPtr conn,
 {
     int ret;
 
-    /* Refresh allocation / permissions info in case its changed */
-    ret = virStorageBackendUpdateVolInfo(vol, false,
+    /* Refresh allocation / permissions info in case its changed
+     * don't update the capacity value for this pass
+     */
+    ret = virStorageBackendUpdateVolInfo(vol, false, false,
                                          VIR_STORAGE_VOL_FS_OPEN_FLAGS);
     if (ret < 0)
         return ret;

src/storage/storage_backend_gluster.c

@@ -267,7 +267,7 @@ virStorageBackendGlusterRefreshVol(virStorageBackendGlusterStatePtr state,
     if (VIR_ALLOC(vol) < 0)
         goto cleanup;
 
-    if (virStorageBackendUpdateVolTargetInfoFD(&vol->target, -1, st) < 0)
+    if (virStorageBackendUpdateVolTargetInfoFD(&vol->target, -1, st, true) < 0)
         goto cleanup;
 
     if (virStorageBackendGlusterSetMetadata(state, vol, name) < 0)

src/storage/storage_backend_logical.c

@@ -149,7 +149,7 @@ virStorageBackendLogicalMakeVol(char **const groups,
     if (!vol->key && VIR_STRDUP(vol->key, groups[2]) < 0)
         goto cleanup;
 
-    if (virStorageBackendUpdateVolInfo(vol, false,
+    if (virStorageBackendUpdateVolInfo(vol, true, false,
                                        VIR_STORAGE_VOL_OPEN_DEFAULT) < 0)
         goto cleanup;
 

src/storage/storage_backend_mpath.c

@@ -60,7 +60,7 @@ virStorageBackendMpathNewVol(virStoragePoolObjPtr pool,
     if (virAsprintf(&vol->target.path, "/dev/%s", dev) < 0)
         goto cleanup;
 
-    if (virStorageBackendUpdateVolInfo(vol, true,
+    if (virStorageBackendUpdateVolInfo(vol, true, true,
                                        VIR_STORAGE_VOL_OPEN_DEFAULT) < 0) {
         goto cleanup;
     }

src/storage/storage_backend_scsi.c

@@ -199,7 +199,7 @@ virStorageBackendSCSINewLun(virStoragePoolObjPtr pool,
         goto free_vol;
     }
 
-    if (virStorageBackendUpdateVolInfo(vol, true,
+    if (virStorageBackendUpdateVolInfo(vol, true, true,
                                        VIR_STORAGE_VOL_OPEN_DEFAULT) < 0) {
         retval = -1;
         goto free_vol;