locking: Add APIs to lock individual image files

Add helper APIs to manage individual image files rather than disks. To
simplify the addition some parts of the code were refactored in this
patch.

src/libvirt_private.syms

@@ -862,6 +862,8 @@ virRegisterStorageDriver;
 # locking/domain_lock.h
 virDomainLockDiskAttach;
 virDomainLockDiskDetach;
+virDomainLockImageAttach;
+virDomainLockImageDetach;
 virDomainLockLeaseAttach;
 virDomainLockLeaseDetach;
 virDomainLockProcessInquire;

src/locking/domain_lock.c

@@ -68,14 +68,13 @@ static int virDomainLockManagerAddLease(virLockManagerPtr lock,
 }
 
 
-static int virDomainLockManagerAddDisk(virLockManagerPtr lock,
-                                       virDomainDiskDefPtr disk)
+static int virDomainLockManagerAddImage(virLockManagerPtr lock,
+                                        virStorageSourcePtr src)
 {
     unsigned int diskFlags = 0;
-    const char *src = virDomainDiskGetSource(disk);
-    int type = virDomainDiskGetType(disk);
+    int type = virStorageSourceGetActualType(src);
 
-    if (!src)
+    if (!src->path)
         return 0;
 
     if (!(type == VIR_STORAGE_TYPE_BLOCK ||
@@ -83,24 +82,25 @@ static int virDomainLockManagerAddDisk(virLockManagerPtr lock,
           type == VIR_STORAGE_TYPE_DIR))
         return 0;
 
-    if (disk->src->readonly)
+    if (src->readonly)
         diskFlags |= VIR_LOCK_MANAGER_RESOURCE_READONLY;
-    if (disk->src->shared)
+    if (src->shared)
         diskFlags |= VIR_LOCK_MANAGER_RESOURCE_SHARED;
 
-    VIR_DEBUG("Add disk %s", src);
+    VIR_DEBUG("Add disk %s", src->path);
     if (virLockManagerAddResource(lock,
                                   VIR_LOCK_MANAGER_RESOURCE_TYPE_DISK,
-                                  src,
+                                  src->path,
                                   0,
                                   NULL,
                                   diskFlags) < 0) {
-        VIR_DEBUG("Failed add disk %s", src);
+        VIR_DEBUG("Failed add disk %s", src->path);
         return -1;
     }
     return 0;
 }
 
+
 static virLockManagerPtr virDomainLockManagerNew(virLockManagerPluginPtr plugin,
                                                  const char *uri,
                                                  virDomainObjPtr dom,
@@ -148,9 +148,12 @@ static virLockManagerPtr virDomainLockManagerNew(virLockManagerPluginPtr plugin,
                 goto error;
 
         VIR_DEBUG("Adding disks");
-        for (i = 0; i < dom->def->ndisks; i++)
-            if (virDomainLockManagerAddDisk(lock, dom->def->disks[i]) < 0)
+        for (i = 0; i < dom->def->ndisks; i++) {
+            virDomainDiskDefPtr disk = dom->def->disks[i];
+
+            if (virDomainLockManagerAddImage(lock, disk->src) < 0)
                 goto error;
+        }
     }
 
     return lock;
@@ -247,21 +250,20 @@ int virDomainLockProcessInquire(virLockManagerPluginPtr plugin,
 }
 
 
-int virDomainLockDiskAttach(virLockManagerPluginPtr plugin,
-                            const char *uri,
-                            virDomainObjPtr dom,
-                            virDomainDiskDefPtr disk)
+int virDomainLockImageAttach(virLockManagerPluginPtr plugin,
+                             const char *uri,
+                             virDomainObjPtr dom,
+                             virStorageSourcePtr src)
 {
     virLockManagerPtr lock;
     int ret = -1;
 
-    VIR_DEBUG("plugin=%p dom=%p disk=%p",
-              plugin, dom, disk);
+    VIR_DEBUG("plugin=%p dom=%p src=%p", plugin, dom, src);
 
     if (!(lock = virDomainLockManagerNew(plugin, uri, dom, false)))
         return -1;
 
-    if (virDomainLockManagerAddDisk(lock, disk) < 0)
+    if (virDomainLockManagerAddImage(lock, src) < 0)
         goto cleanup;
 
     if (virLockManagerAcquire(lock, NULL, 0,
@@ -276,20 +278,29 @@ int virDomainLockDiskAttach(virLockManagerPluginPtr plugin,
     return ret;
 }
 
-int virDomainLockDiskDetach(virLockManagerPluginPtr plugin,
+
+int virDomainLockDiskAttach(virLockManagerPluginPtr plugin,
+                            const char *uri,
                             virDomainObjPtr dom,
                             virDomainDiskDefPtr disk)
+{
+    return virDomainLockImageAttach(plugin, uri, dom, disk->src);
+}
+
+
+int virDomainLockImageDetach(virLockManagerPluginPtr plugin,
+                             virDomainObjPtr dom,
+                             virStorageSourcePtr src)
 {
     virLockManagerPtr lock;
     int ret = -1;
 
-    VIR_DEBUG("plugin=%p dom=%p disk=%p",
-              plugin, dom, disk);
+    VIR_DEBUG("plugin=%p dom=%p src=%p", plugin, dom, src);
 
     if (!(lock = virDomainLockManagerNew(plugin, NULL, dom, false)))
         return -1;
 
-    if (virDomainLockManagerAddDisk(lock, disk) < 0)
+    if (virDomainLockManagerAddImage(lock, src) < 0)
         goto cleanup;
 
     if (virLockManagerRelease(lock, NULL, 0) < 0)
@@ -304,6 +315,14 @@ int virDomainLockDiskDetach(virLockManagerPluginPtr plugin,
 }
 
 
+int virDomainLockDiskDetach(virLockManagerPluginPtr plugin,
+                            virDomainObjPtr dom,
+                            virDomainDiskDefPtr disk)
+{
+    return virDomainLockImageDetach(plugin, dom, disk->src);
+}
+
+
 int virDomainLockLeaseAttach(virLockManagerPluginPtr plugin,
                              const char *uri,
                              virDomainObjPtr dom,

src/locking/domain_lock.h

@@ -50,6 +50,14 @@ int virDomainLockDiskDetach(virLockManagerPluginPtr plugin,
                             virDomainObjPtr dom,
                             virDomainDiskDefPtr disk);
 
+int virDomainLockImageAttach(virLockManagerPluginPtr plugin,
+                             const char *uri,
+                             virDomainObjPtr dom,
+                             virStorageSourcePtr src);
+int virDomainLockImageDetach(virLockManagerPluginPtr plugin,
+                             virDomainObjPtr dom,
+                             virStorageSourcePtr src);
+
 int virDomainLockLeaseAttach(virLockManagerPluginPtr plugin,
                              const char *uri,
                              virDomainObjPtr dom,