[libvirt] [PATCH v2 9/9] virstoragefile: Add node-name

[Matthias Gatto]

Add nodename inside virstoragefile
During xml backingStore parsing, look for a nodename attribute in the disk
declaration if this one is a quorum, if a nodename is found, add it to
the virStorageSource otherwise create a new one with a random name.
Take inspiration from this patch to create the nodename:
http://lists.gnu.org/archive/html/qemu-devel/2014-05/msg03209.html

Durring xml backingStore formating, look for a nodename attribute inside the
virStorageSource struct, and add it to the disk element.

Use the nodename to create the quorum in qemuBuildQuorumStr.

Signed-off-by: Matthias Gatto <matthias.gatto at outscale.com>
---
 docs/formatdomain.html.in |  7 +++++++
 src/conf/domain_conf.c    | 25 +++++++++++++++++++++++++
 src/qemu/qemu_command.c   |  3 +++
 src/util/virstoragefile.c |  4 ++++
 src/util/virstoragefile.h |  1 +
 5 files changed, 40 insertions(+)

diff --git a/docs/formatdomain.html.in b/docs/formatdomain.html.in
index 7ab8cbb..1e1baf8 100644
--- a/docs/formatdomain.html.in
+++ b/docs/formatdomain.html.in
@@ -2135,6 +2135,13 @@
             <code>vda[2]</code> refers to the backing store with
             <code>index='2'</code> of the disk with <code>vda</code> target.
           </dd>
+          <dt><code>nodename</code> attribute
+          <span class="since">since 1.2.13</span></dt>
+          <dd>
+            When the backing store is a quorum child, we can use this attribute
+            to define the node-name of a child. If this atribute is undefine,
+            a random nodename is generate.
+          </dd>
           <dt><code>format</code> sub-element</dt>
           <dd>
             The <code>format</code> element contains <code>type</code>
diff --git a/src/conf/domain_conf.c b/src/conf/domain_conf.c
index 64fe06b..e674960 100644
--- a/src/conf/domain_conf.c
+++ b/src/conf/domain_conf.c
@@ -56,6 +56,7 @@
 #include "network_conf.h"
 #include "virtpm.h"
 #include "virstring.h"
+#include "virrandom.h"
 
 #define VIR_FROM_THIS VIR_FROM_DOMAIN
 
@@ -5631,6 +5632,8 @@ virDomainDiskThresholdParse(virStorageSourcePtr src,
 }
 
 
+#define GEN_NODE_NAME_PREFIX    "libvirt"
+#define GEN_NODE_NAME_MAX_LEN   (sizeof(GEN_NODE_NAME_PREFIX) + 8 + 8)
 static int
 virDomainDiskBackingStoreParse(xmlXPathContextPtr ctxt,
                                virStorageSourcePtr src,
@@ -5642,6 +5645,7 @@ virDomainDiskBackingStoreParse(xmlXPathContextPtr ctxt,
     xmlNodePtr source = NULL;
     xmlNodePtr cur = NULL;
     char *type = NULL;
+    char *nodeName = NULL;
     char *format = NULL;
     int ret = -1;
     size_t i = 0;
@@ -5675,6 +5679,23 @@ virDomainDiskBackingStoreParse(xmlXPathContextPtr ctxt,
         goto cleanup;
     }
 
+    if (src->type == VIR_STORAGE_TYPE_QUORUM) {
+        if ((nodeName = virXMLPropString(ctxt->node, "nodename"))) {
+            backingStore->nodeName = nodeName;
+        } else {
+            int len;
+            if (VIR_ALLOC_N(nodeName, GEN_NODE_NAME_MAX_LEN) < 0)
+                goto cleanup;
+            snprintf(nodeName, GEN_NODE_NAME_MAX_LEN,
+                     "%s%08x", GEN_NODE_NAME_PREFIX, (int)pos);
+            len = strlen(nodeName);
+            while (len < GEN_NODE_NAME_MAX_LEN - 1)
+                nodeName[len++] = virRandomInt('Z' - 'A') + 'A';
+            nodeName[GEN_NODE_NAME_MAX_LEN - 1] = '\0';
+            backingStore->nodeName = nodeName;
+        }
+    }
+
     if (!(format = virXPathString("string(./format/@type)", ctxt))) {
         virReportError(VIR_ERR_XML_ERROR, "%s",
                        _("missing disk backing store format"));
@@ -5726,6 +5747,8 @@ virDomainDiskBackingStoreParse(xmlXPathContextPtr ctxt,
     ctxt->node = save_ctxt;
     return ret;
 }
+#undef GEN_NODE_NAME_PREFIX
+#undef GEN_NODE_NAME_MAX_LEN
 
 #define VENDOR_LEN  8
 #define PRODUCT_LEN 16
@@ -16770,6 +16793,8 @@ virDomainDiskBackingStoreFormat(virBufferPtr buf,
                           type, idx);
         if (backingStore->threshold)
             virBufferAsprintf(buf, " threshold='%lu'", backingStore->threshold);
+        if (backingStore->nodeName)
+            virBufferAsprintf(buf, " nodename='%s'", backingStore->nodeName);
         virBufferAddLit(buf, ">\n");
         virBufferAdjustIndent(buf, 2);
 
diff --git a/src/qemu/qemu_command.c b/src/qemu/qemu_command.c
index be7f66c..5a5e9cd 100644
--- a/src/qemu/qemu_command.c
+++ b/src/qemu/qemu_command.c
@@ -3273,6 +3273,9 @@ qemuBuildQuorumStr(virConnectPtr conn,
                           toAppend, i,
                           virStorageFileFormatTypeToString(backingStore->format));
 
+        virBufferAsprintf(opt, ",%schildren.%lu.node-name=%s",
+                          toAppend, i, backingStore->nodeName);
+
         if (qemuBuildQuorumFileSourceStr(conn, backingStore, opt, tmp) == false)
             goto error;
 
diff --git a/src/util/virstoragefile.c b/src/util/virstoragefile.c
index d0aa404..1623618 100644
--- a/src/util/virstoragefile.c
+++ b/src/util/virstoragefile.c
@@ -1961,6 +1961,9 @@ virStorageSourceCopy(const virStorageSource *src,
         !(ret->auth = virStorageAuthDefCopy(src->auth)))
         goto error;
 
+    if (src->nodeName && VIR_STRDUP(ret->nodeName, src->nodeName) < 0)
+        goto error;
+
     for (i = 0; i < src->nBackingStores; ++i) {
         if (backingChain && virStorageSourceGetBackingStore(src, i)) {
             if (!virStorageSourceSetBackingStore(ret,
@@ -2106,6 +2109,7 @@ virStorageSourceBackingStoreClear(virStorageSourcePtr def)
 
     VIR_FREE(def->relPath);
     VIR_FREE(def->backingStoreRaw);
+    VIR_FREE(def->nodeName);
 
     /* recursively free backing chain */
     for (i = 0; i < def->nBackingStores; ++i)
diff --git a/src/util/virstoragefile.h b/src/util/virstoragefile.h
index 3b43a6d..1c8c8cb 100644
--- a/src/util/virstoragefile.h
+++ b/src/util/virstoragefile.h
@@ -275,6 +275,7 @@ struct _virStorageSource {
     virStorageSourcePtr backingStore;
     size_t      nBackingStores;
     size_t      threshold;
+    char        *nodeName;
 
     /* metadata for storage driver access to remote and local volumes */
     virStorageDriverDataPtr drv;
-- 
1.8.3.1