From e4c6d4ae557a5de3a4b9a7e789df0e8f1d140557 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Tom=C3=A1=C5=A1=20Golembiovsk=C3=BD?= <tgolembi@redhat.com>
Date: Mon, 13 Feb 2017 23:53:43 +0100
Subject: [PATCH] util: storage: add JSON backing volume parser 'raw' block
 driver
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The 'raw' block driver in Qemu is not directly interesting from
libvirt's perspective, but it can be layered above some other block
drivers and this may be interesting for the user.

The patch adds support for the 'raw' block driver. The driver is treated
simply as a pass-through and child driver in JSON is queried to get the
necessary information.

Signed-off-by: Tomáš Golembiovský <tgolembi@redhat.com>
---
 src/util/virstoragefile.c | 16 ++++++++++++++++
 tests/virstoragetest.c    |  6 ++++++
 2 files changed, 22 insertions(+)

diff --git a/src/util/virstoragefile.c b/src/util/virstoragefile.c
index 715c0429d7..c9420fdb79 100644
--- a/src/util/virstoragefile.c
+++ b/src/util/virstoragefile.c
@@ -2647,6 +2647,11 @@ virStorageSourceParseBackingColon(virStorageSourcePtr src,
 }
 
 
+static int
+virStorageSourceParseBackingJSONInternal(virStorageSourcePtr src,
+                                         virJSONValuePtr json);
+
+
 static int
 virStorageSourceParseBackingJSONPath(virStorageSourcePtr src,
                                      virJSONValuePtr json,
@@ -2963,6 +2968,16 @@ virStorageSourceParseBackingJSONRBD(virStorageSourcePtr src,
     return -1;
 }
 
+static int
+virStorageSourceParseBackingJSONRaw(virStorageSourcePtr src,
+                                    virJSONValuePtr json,
+                                    int opaque ATTRIBUTE_UNUSED)
+{
+    /* There are no interesting attributes in raw driver.
+     * Treat it as pass-through.
+     */
+    return virStorageSourceParseBackingJSONInternal(src, json);
+}
 
 struct virStorageSourceJSONDriverParser {
     const char *drvname;
@@ -2985,6 +3000,7 @@ static const struct virStorageSourceJSONDriverParser jsonParsers[] = {
     {"sheepdog", virStorageSourceParseBackingJSONSheepdog, 0},
     {"ssh", virStorageSourceParseBackingJSONSSH, 0},
     {"rbd", virStorageSourceParseBackingJSONRBD, 0},
+    {"raw", virStorageSourceParseBackingJSONRaw, 0},
 };
 
 
diff --git a/tests/virstoragetest.c b/tests/virstoragetest.c
index 36567753ba..984994d8e7 100644
--- a/tests/virstoragetest.c
+++ b/tests/virstoragetest.c
@@ -1496,6 +1496,12 @@ mymain(void)
                        "<source protocol='rbd' name='testshare'>\n"
                        "  <host name='example.com'/>\n"
                        "</source>\n");
+    TEST_BACKING_PARSE("json:{ \"file\": { "
+                                "\"driver\": \"raw\","
+                                "\"file\": {"
+                                    "\"driver\": \"file\","
+                                    "\"filename\": \"/path/to/file\" } } }",
+                       "<source file='/path/to/file'/>\n");
 
  cleanup:
     /* Final cleanup */