[libvirt] [PATCH 6/6] storage: Introduce storagePoolUpdateAllState function

[Erik Skultety]

The 'checkPool' callback was originally part of the storageDriverAutostart function,
but the pools need to be checked earlier during initialization phase,
otherwise we can't start a domain which mountsa volume after daemon's
restarted. This is because qemuProcessReconnect is called earlier than
storageDriverAutostart. Therefore the 'checkPool' logic has been moved to
storagePoolUpdateAllState which is called inside storageDriverInitialize.

We also need a valid 'conn' reference to be able to execute 'refreshPool'
during initialization phase. Though it isn't available until storageDriverAutostart
all of our storage backends do ignore 'conn' pointer, except for RBD,
but RBD doesn't support 'checkPool' callback, so it's safe to pass
conn = NULL in this case.

Resolves: https://bugzilla.redhat.com/show_bug.cgi?id=1177733
---
 src/storage/storage_driver.c | 74 ++++++++++++++++++++++++++++++++++++--------
 1 file changed, 61 insertions(+), 13 deletions(-)

diff --git a/src/storage/storage_driver.c b/src/storage/storage_driver.c
index 36c05b3..12e94ad 100644
--- a/src/storage/storage_driver.c
+++ b/src/storage/storage_driver.c
@@ -75,6 +75,64 @@ static void storageDriverUnlock(void)
 }
 
 static void
+storagePoolUpdateAllState(void)
+{
+    size_t i;
+    bool active = false;
+
+    for (i = 0; i < driver->pools.count; i++) {
+        virStoragePoolObjPtr pool = driver->pools.objs[i];
+        virStorageBackendPtr backend;
+
+        virStoragePoolObjLock(pool);
+        if (!virStoragePoolObjIsActive(pool)) {
+            virStoragePoolObjUnlock(pool);
+            continue;
+        }
+
+        if ((backend = virStorageBackendForType(pool->def->type)) == NULL) {
+            VIR_ERROR(_("Missing backend %d"), pool->def->type);
+            virStoragePoolObjUnlock(pool);
+            continue;
+        }
+
+        /* Backends which do not support 'checkPool' are considered
+         * inactive by default.
+         */
+        if (backend->checkPool &&
+            backend->checkPool(pool, &active) < 0) {
+            virErrorPtr err = virGetLastError();
+            VIR_ERROR(_("Failed to initialize storage pool '%s': %s"),
+                      pool->def->name, err ? err->message :
+                      _("no error message found"));
+            virStoragePoolObjUnlock(pool);
+            continue;
+        }
+
+        /* We can pass NULL as connection, most backends do not use
+         * it anyway, but if they do and fail, we want to log error and
+         * continue with other pools.
+         */
+        if (active) {
+            virStoragePoolObjClearVols(pool);
+            if (backend->refreshPool(NULL, pool) < 0) {
+                virErrorPtr err = virGetLastError();
+                if (backend->stopPool)
+                    backend->stopPool(NULL, pool);
+                VIR_ERROR(_("Failed to restart storage pool '%s': %s"),
+                          pool->def->name, err ? err->message :
+                          _("no error message found"));
+                virStoragePoolObjUnlock(pool);
+                continue;
+            }
+        }
+
+        pool->active = active;
+        virStoragePoolObjUnlock(pool);
+    }
+}
+
+static void
 storageDriverAutostart(void)
 {
     size_t i;
@@ -95,23 +153,11 @@ storageDriverAutostart(void)
 
         virStoragePoolObjLock(pool);
         if ((backend = virStorageBackendForType(pool->def->type)) == NULL) {
-            VIR_ERROR(_("Missing backend %d"), pool->def->type);
             virStoragePoolObjUnlock(pool);
             continue;
         }
 
-        if (backend->checkPool &&
-            backend->checkPool(pool, &started) < 0) {
-            virErrorPtr err = virGetLastError();
-            VIR_ERROR(_("Failed to initialize storage pool '%s': %s"),
-                      pool->def->name, err ? err->message :
-                      _("no error message found"));
-            virStoragePoolObjUnlock(pool);
-            continue;
-        }
-
-        if (!started &&
-            pool->autostart &&
+        if (pool->autostart &&
             !virStoragePoolObjIsActive(pool)) {
             if (backend->startPool &&
                 backend->startPool(conn, pool) < 0) {
@@ -215,6 +261,8 @@ storageStateInitialize(bool privileged,
                                      driver->autostartDir) < 0)
         goto error;
 
+    storagePoolUpdateAllState();
+
     storageDriverUnlock();
 
     ret = 0;
-- 
1.9.3