Some applications need to be able to query a guest's disk info,
even for paths not managed by the storage pool APIs. This adds
a very simple API to get this information, modelled on the
virStorageVolGetInfo API, but with an extra field 'physical'.
Normally 'physical' and 'allocation' will be identical, but
in the case of a qcow2-like file stored inside a block device
'physical' will give the block device size, while 'allocation'
will give the qcow2 image size
* include/libvirt/libvirt.h.in: Define virDomainGetBlockInfo
---
include/libvirt/libvirt.h.in | 36 ++++++++++++++++++++++++++++++++++++
1 files changed, 36 insertions(+), 0 deletions(-)
diff --git a/include/libvirt/libvirt.h.in b/include/libvirt/libvirt.h.in
index 4addc62..3ce59cf 100644
--- a/include/libvirt/libvirt.h.in
+++ b/include/libvirt/libvirt.h.in
@@ -733,6 +733,42 @@ int virDomainBlockPeek (virDomainPtr dom,
void *buffer,
unsigned int flags);
+
+/** virDomainBlockInfo:
+ *
+ * This struct provides information about the size of a block device backing store
+ *
+ * Examples:
+ *
+ * - Fully allocated raw file in filesystem:
+ * * capacity, allocation, physical: All the same
+ *
+ * - Sparse raw file in filesystem:
+ * * capacity: logical size of the file
+ * * allocation, physical: number of blocks allocated to file
+ *
+ * - qcow2 file in filesystem
+ * * capacity: logical size from qcow2 header
+ * * allocation, physical: logical size of the file / highest qcow extent (identical)
+ *
+ * - qcow2 file in a block device
+ * * capacity: logical size from qcow2 header
+ * * allocation: highest qcow extent written
+ * * physical: size of the block device container
+ */
+typedef struct _virDomainBlockInfo virDomainBlockInfo;
+typedef virDomainBlockInfo *virDomainBlockInfoPtr;
+struct _virDomainBlockInfo {
+ unsigned long long capacity; /* logical size of the block device backing image */
+ unsigned long long allocation; /* allocated extent of the block device backing image */
+ unsigned long long physical; /* physical size of the container of the backing image */
+};
+
+int virDomainGetBlockInfo(virDomainPtr dom,
+ const char *path,
+ virDomainBlockInfoPtr info,
+ unsigned int flags);
+
/* Memory peeking flags. */
typedef enum {
VIR_MEMORY_VIRTUAL = 1, /* addresses are virtual addresses */
--
1.6.6.1
--
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