[libvirt] [PATCH v2 27/32] Introduce virStorageVol{Download, Upload}Flags

[Michal Privoznik]

These flags to APIs will tell if caller wants to use sparse
stream for storage transfer. At the same time, it's safe to
enable them in storage driver frontend and rely on our backends
checking the flags. This way we can enable specific flags only on
some specific backends, e.g. enable
VIR_STORAGE_VOL_DOWNLOAD_SPARSE_STREAM for filesystem backend but
not iSCSI backend.

Signed-off-by: Michal Privoznik <mprivozn at redhat.com>
---
 include/libvirt/libvirt-storage.h | 9 +++++++++
 src/libvirt-storage.c             | 4 ++--
 src/remote/remote_protocol.x      | 2 ++
 src/storage/storage_driver.c      | 4 ++--
 4 files changed, 15 insertions(+), 4 deletions(-)

diff --git a/include/libvirt/libvirt-storage.h b/include/libvirt/libvirt-storage.h
index db6f2b4..e98e8a5 100644
--- a/include/libvirt/libvirt-storage.h
+++ b/include/libvirt/libvirt-storage.h
@@ -337,11 +337,20 @@ virStorageVolPtr        virStorageVolCreateXMLFrom      (virStoragePoolPtr pool,
                                                          const char *xmldesc,
                                                          virStorageVolPtr clonevol,
                                                          unsigned int flags);
+
+typedef enum {
+    VIR_STORAGE_VOL_DOWNLOAD_SPARSE_STREAM = 1 << 0, /* Use sparse stream */
+} virStorageVolDownloadFlags;
+
 int                     virStorageVolDownload           (virStorageVolPtr vol,
                                                          virStreamPtr stream,
                                                          unsigned long long offset,
                                                          unsigned long long length,
                                                          unsigned int flags);
+typedef enum {
+    VIR_STORAGE_VOL_UPLOAD_SPARSE_STREAM = 1 << 0,  /* Use sparse stream */
+} virStorageVolUploadFlags;
+
 int                     virStorageVolUpload             (virStorageVolPtr vol,
                                                          virStreamPtr stream,
                                                          unsigned long long offset,
diff --git a/src/libvirt-storage.c b/src/libvirt-storage.c
index 1ce6745..cd8ce16 100644
--- a/src/libvirt-storage.c
+++ b/src/libvirt-storage.c
@@ -1549,7 +1549,7 @@ virStorageVolCreateXMLFrom(virStoragePoolPtr pool,
  * @stream: stream to use as output
  * @offset: position in @vol to start reading from
  * @length: limit on amount of data to download
- * @flags: extra flags; not used yet, so callers should always pass 0
+ * @flags: bitwise-OR of virStorageVolDownloadFlags
  *
  * Download the content of the volume as a stream. If @length
  * is zero, then the remaining contents of the volume after
@@ -1613,7 +1613,7 @@ virStorageVolDownload(virStorageVolPtr vol,
  * @stream: stream to use as input
  * @offset: position to start writing to
  * @length: limit on amount of data to upload
- * @flags: extra flags; not used yet, so callers should always pass 0
+ * @flags: bitwise-OR of virStorageVolUploadFlags
  *
  * Upload new content to the volume from a stream. This call
  * will fail if @offset + @length exceeds the size of the
diff --git a/src/remote/remote_protocol.x b/src/remote/remote_protocol.x
index bab8ef2..35f56d4 100644
--- a/src/remote/remote_protocol.x
+++ b/src/remote/remote_protocol.x
@@ -4753,6 +4753,7 @@ enum remote_procedure {
     /**
      * @generate: both
      * @writestream: 1
+     * @sparseflag: VIR_STORAGE_VOL_UPLOAD_SPARSE_STREAM
      * @acl: storage_vol:data_write
      */
     REMOTE_PROC_STORAGE_VOL_UPLOAD = 208,
@@ -4760,6 +4761,7 @@ enum remote_procedure {
     /**
      * @generate: both
      * @readstream: 1
+     * @sparseflag: VIR_STORAGE_VOL_DOWNLOAD_SPARSE_STREAM
      * @acl: storage_vol:data_read
      */
     REMOTE_PROC_STORAGE_VOL_DOWNLOAD = 209,
diff --git a/src/storage/storage_driver.c b/src/storage/storage_driver.c
index eb5f688..a8ce96d 100644
--- a/src/storage/storage_driver.c
+++ b/src/storage/storage_driver.c
@@ -2161,7 +2161,7 @@ storageVolDownload(virStorageVolPtr obj,
     virStorageVolDefPtr vol = NULL;
     int ret = -1;
 
-    virCheckFlags(0, -1);
+    virCheckFlags(VIR_STORAGE_VOL_DOWNLOAD_SPARSE_STREAM, -1);
 
     if (!(vol = virStorageVolDefFromVol(obj, &pool, &backend)))
         return -1;
@@ -2323,7 +2323,7 @@ storageVolUpload(virStorageVolPtr obj,
     virStorageVolStreamInfoPtr cbdata = NULL;
     int ret = -1;
 
-    virCheckFlags(0, -1);
+    virCheckFlags(VIR_STORAGE_VOL_UPLOAD_SPARSE_STREAM, -1);
 
     if (!(vol = virStorageVolDefFromVol(obj, &pool, &backend)))
         return -1;
-- 
2.8.3